HAITIANS EATING MUD

[spectre]

http://en.wikipedia.org/wiki/Pica_(disorder)
http://en.wikipedia.org/wiki/Clay_eating

"Geophagy is the practice of eating earthy or soil-like substances
such as clay, and chalk, in order to obtain essential nutrients such
as sulfur and phosphorus from the soil. It is closely related to pica,
a classified eating disorder in the DSM-IV characterized by abnormal
cravings for nonfood items.

The many possible health benefits of geophagy remain under study and
are much debated. Many scientists believe that it is only harmful,
while others argue that there may be adaptive benefits to the
practice, since humans and animals alike have engaged in it for
thousands of years."

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BUTTER-FLAVORED
'In Haiti, where three-quarters of the population earns less than $2 a
day and one in five children is chronically malnourished, the one
business booming amid all the gloom is the selling of patties made of
mud, oil and sugar, typically consumed only by the most destitute.

“It’s salty and it has butter and you don’t know you’re eating dirt,”
said Olwich Louis Jeune, 24, who has taken to eating them more often
in recent months. “It makes your stomach quiet down.”'

http://video.on.nytimes.com/?fr_story=b7ed2a4ccb7fdae5294a5dbad78a45306d828d99
http://www.nytimes.com/2008/04/18/world/americas/18food.html
Across Globe, Empty Bellies Bring Rising Anger
BY Marc Lacey / April 18, 2008

PORT-AU-PRINCE, Haiti — Hunger bashed in the front gate of Haiti’s
presidential palace. Hunger poured onto the streets, burning tires and
taking on soldiers and the police. Hunger sent the country’s prime
minister packing. Haiti’s hunger, that burn in the belly that so many
here feel, has become fiercer than ever in recent days as global food
prices spiral out of reach, spiking as much as 45 percent since the
end of 2006 and turning Haitian staples like beans, corn and rice into
closely guarded treasures.

Saint Louis Meriska’s children ate two spoonfuls of rice apiece as
their only meal recently and then went without any food the following
day. His eyes downcast, his own stomach empty, the unemployed father
said forlornly, “They look at me and say, ‘Papa, I’m hungry,’ and I
have to look away. It’s humiliating and it makes you angry.”

That anger is palpable across the globe. The food crisis is not only
being felt among the poor but is also eroding the gains of the working
and middle classes, sowing volatile levels of discontent and putting
new pressures on fragile governments.

In Cairo, the military is being put to work baking bread as rising
food prices threaten to become the spark that ignites wider anger at a
repressive government. In Burkina Faso and other parts of sub-Saharan
Africa, food riots are breaking out as never before. In reasonably
prosperous Malaysia, the ruling coalition was nearly ousted by voters
who cited food and fuel price increases as their main concerns.

“It’s the worst crisis of its kind in more than 30 years,” said
Jeffrey D. Sachs, the economist and special adviser to the United
Nations secretary general, Ban Ki-moon. “It’s a big deal and it’s
obviously threatening a lot of governments. There are a number of
governments on the ropes, and I think there’s more political fallout
to come.”

Indeed, as it roils developing nations, the spike in commodity prices
— the biggest since the Nixon administration — has pitted the globe’s
poorer south against the relatively wealthy north, adding to demands
for reform of rich nations’ farm and environmental policies. But
experts say there are few quick fixes to a crisis tied to so many
factors, from strong demand for food from emerging economies like
China’s to rising oil prices to the diversion of food resources to
make biofuels.

There are no scripts on how to handle the crisis, either. In Asia,
governments are putting in place measures to limit hoarding of rice
after some shoppers panicked at price increases and bought up
everything they could. Even in Thailand, which produces 10 million
more tons of rice than it consumes and is the world’s largest rice
exporter, supermarkets have placed signs limiting the amount of rice
shoppers are allowed to purchase. But there is also plenty of
nervousness and confusion about how best to proceed and just how bad
the impact may ultimately be, particularly as already strapped
governments struggle to keep up their food subsidies.

‘Scandalous Storm’

“This is a perfect storm,” President Elías Antonio Saca of El Salvador
said Wednesday at the World Economic Forum on Latin America in Cancún,
Mexico. “How long can we withstand the situation? We have to feed our
people, and commodities are becoming scarce. This scandalous storm
might become a hurricane that could upset not only our economies but
also the stability of our countries.”

In Asia, if Prime Minister Abdullah Ahmad Badawi of Malaysia steps
down, which is looking increasingly likely amid postelection turmoil
within his party, he may be that region’s first high- profile
political casualty of fuel and food price inflation. In Indonesia,
fearing protests, the government recently revised its 2008 budget,
increasing the amount it will spend on food subsidies by about $280
million. “The biggest concern is food riots,” said H.S. Dillon, a
former adviser to Indonesia’s Ministry of Agriculture. Referring to
small but widespread protests touched off by a rise in soybean prices
in January, he said, “It has happened in the past and can happen
again.”

Last month in Senegal, one of Africa’s oldest and most stable
democracies, police in riot gear beat and used tear gas against people
protesting high food prices and later raided a television station that
broadcast images of the event. Many Senegalese have expressed anger at
President Abdoulaye Wade for spending lavishly on roads and five-star
hotels for an Islamic summit meeting last month while many people are
unable to afford rice or fish. “Why are these riots happening?” asked
Arif Husain, senior food security analyst at the World Food Program,
which has issued urgent appeals for donations. “The human instinct is
to survive, and people are going to do no matter what to survive. And
if you’re hungry you get angry quicker.”

Leaders who ignore the rage do so at their own risk. President René
Préval of Haiti appeared to taunt the populace as the chorus of
complaints about la vie chère — the expensive life — grew. He said if
Haitians could afford cellphones, which many do carry, they should be
able to feed their families. “If there is a protest against the rising
prices,” he said, “come get me at the palace and I will demonstrate
with you.”

When they came, filled with rage and by the thousands, he huddled
inside and his presidential guards, with United Nations peacekeeping
troops, rebuffed them. Within days, opposition lawmakers had voted out
Mr. Préval’s prime minister, Jacques-Édouard Alexis, forcing him to
reconstitute his government. Fragile in even the best of times,
Haiti’s population and politics are now both simmering.

“Why were we surprised?” asked Patrick Élie, a Haitian political
activist who followed the food riots in Africa earlier in the year and
feared they might come to Haiti. “When something is coming your way
all the way from Burkina Faso you should see it coming. What we had
was like a can of gasoline that the government left for someone to
light a match to it.”

Dwindling Menus

The rising prices are altering menus, and not for the better. In
India, people are scrimping on milk for their children. Daily bowls of
dal are getting thinner, as a bag of lentils is stretched across a few
more meals. Maninder Chand, an auto-rickshaw driver in New Delhi, said
his family had given up eating meat altogether for the last several
weeks. Another rickshaw driver, Ravinder Kumar Gupta, said his wife
had stopped seasoning their daily lentils, their chief source of
protein, with the usual onion and spices because the price of cooking
oil was now out of reach. These days, they eat bowls of watery,
tasteless dal, seasoned only with salt.

Down Cairo’s Hafziyah Street, peddlers selling food from behind wood
carts bark out their prices. But few customers can afford their fish
or chicken, which bake in the hot sun. Food prices have doubled in two
months. Ahmed Abul Gheit, 25, sat on a cheap, stained wooden chair by
his own pile of rotting tomatoes. “We can’t even find food,” he said,
looking over at his friend Sobhy Abdullah, 50. Then raising his hands
toward the sky, as if in prayer, he said, “May God take the guy I have
in mind.” Mr. Abdullah nodded, knowing full well that the “guy” was
President Hosni Mubarak.

The government’s ability to address the crisis is limited, however. It
already spends more on subsidies, including gasoline and bread, than
on education and health combined. “If all the people rise, then the
government will resolve this,” said Raisa Fikry, 50, whose husband
receives a pension equal to about $83 a month, as she shopped for
vegetables. “But everyone has to rise together. People get scared. But
we will all have to rise together.” It is the kind of talk that has
prompted the government to treat its economic woes as a security
threat, dispatching riot forces with a strict warning that anyone who
takes to the streets will be dealt with harshly.

Niger does not need to be reminded that hungry citizens overthrow
governments. The country’s first postcolonial president, Hamani Diori,
was toppled amid allegations of rampant corruption in 1974 as millions
starved during a drought. More recently, in 2005, it was mass protests
in Niamey, the Nigerien capital, that made the government sit up and
take notice of that year’s food crisis, which was caused by a complex
mix of poor rains, locust infestation and market manipulation by
traders. “As a result of that experience the government created a
cabinet-level ministry to deal with the high cost of living,” said
Moustapha Kadi, an activist who helped organize marches in 2005. “So
when prices went up this year the government acted quickly to remove
tariffs on rice, which everyone eats. That quick action has kept
people from taking to the streets.”

The Poor Eat Mud

In Haiti, where three-quarters of the population earns less than $2 a
day and one in five children is chronically malnourished, the one
business booming amid all the gloom is the selling of patties made of
mud, oil and sugar, typically consumed only by the most destitute.
“It’s salty and it has butter and you don’t know you’re eating dirt,”
said Olwich Louis Jeune, 24, who has taken to eating them more often
in recent months. “It makes your stomach quiet down.”

But the grumbling in Haiti these days is no longer confined to the
stomach. It is now spray-painted on walls of the capital and shouted
by demonstrators. In recent days, Mr. Préval has patched together a
response, using international aid money and price reductions by
importers to cut the price of a sack of rice by about 15 percent. He
has also trimmed the salaries of some top officials. But those are
considered temporary measures. Real solutions will take years. Haiti,
its agriculture industry in shambles, needs to better feed itself.
Outside investment is the key, although that requires stability, not
the sort of widespread looting and violence that the Haitian food
riots have fostered.

Meanwhile, most of the poorest of the poor suffer silently, too weak
for activism or too busy raising the next generation of hungry. In the
sprawling slum of Haiti’s Cité Soleil, Placide Simone, 29, offered one
of her five offspring to a stranger. “Take one,” she said, cradling a
listless baby and motioning toward four rail-thin toddlers, none of
whom had eaten that day. “You pick. Just feed them.”


-Reporting was contributed by Lydia Polgreen from Niamey, Niger,
Michael Slackman from Cairo, Somini Sengupta from New Delhi, Thomas
Fuller from Bangkok and Peter Gelling from Jakarta, Indonesia.

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COMMENT
http://www.boingboing.net/2008/04/18/starving-people-in-h.html
posted by DloPwop , April 18, 2008

"I live in Haiti, and when I find news about Haiti it's often some
variation on the story "people in Haiti are so poor they eat dirt". I
think it may be more complex than that. I live in an area that is
poor, but not especially poor by Haiti standards. The vendors selling
candy on the side of the road will often have a stack of mud cakes
next to the candy, and I have seen children choosing to buy them
instead of candy - very odd. Apparently, only a particular kind of
fine-grained clay is used, and it is mixed with butter and salt and
flavored. Pregnant women especially seem to crave the mud cakes. I
theorize that there are minerals in the mud that Haitians aren't
getting from the standard rice and beans diet. I'm not saying that the
statement "Haitians are so poor, they have to eat dirt" is 100% false,
but I don't think poverty is the only reason for this. No, I haven't
tried eating one yet."

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MEANWHILE

PAYING FARMERS NOT TO
http://www.npr.org/templates/story/story.php?storyId=4736044
http://news.bbc.co.uk/1/hi/programmes/newsnight/7347123.stm

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GEOPHAGY
http://www.uic.edu/classes/osci/osci590/8_2DirtasFood.htm

8.2 Dirt As Food / Pica / Geophagy
I. ANIMALS THAT EAT DIRT

Known variously as pica or geophagy, eating soil is widespread among
many animals on every continent. It is also frequently observed among
people, especially traditional societies. In wild animals, eating dirt
seems to be a weapon inthe ancient competition between plants and
animals. Geophagy is an animal weapon in the struggle between plant
reproduction strategy and the animal desire for food.

A way of understanding geophagy is to consider the strategies
involved. Many plants use animal mobility to spread seeds by enticing
animals with tasty fruit. The animal digests the pulp, but spits out
the seed or passes it unharmed through its digestive system to be
defecated--freshly potted and fertilized. Plants fend off the animals
by discouraging consumption until the seeds are ready to sprout by
making the pulp bad tasting or even poisonous. Plants manipulate us by
making us wait until the pulp of fruit is suitable to eat--and the
seeds are ready for dispersal.

Seeds possess a concentrated supply of carbohydrates, proteins, and
fats to help them germinate and grow. Bad tastes or poisons are added
to the seeds--or unripe fruit--to fend off animals. How to overcome
them? Parrots will eat soils containing minerals that bind plant
toxins effectively. In fact, they are quite selective in choosing the
most effective soils for their purpose. (My comment: parrots are very
intelligent creatures. Some have learned to speak and understand over
a hundred English words. Trial and error seems to be part of their
behavioral repertoire in nature.)

Are you acquainted with the place name 'lick' such as French Lick in
southern Indiana? It is a place where animals gather to eat soil.
North American wild hoofed animals visit licks, as do bears and many
small mammals. Feeding selected soils to cows, sheep, goats and pigs
results in enhanced growth--by 20% or more.

Antler-growing deer eat soil rich in calcium and magnesium. Some
animals seek out sodium. So, with animals (and humans), in some cases
a particular element is sought. The most compelling need, however,
seems to be the need to detoxify plant products in the diet.

.....

II. HUMAN GEOPHAGY

People seem to use geophagy to protect themselves against plant
toxins. We are accustomed to eating domesticated potatoes. In South
America, however, some Indians regularly eat bitter, toxic wild
potatoes capable of producing stomach pains and vomiting. They have
learned to make the potatoes safe and palatable by eating them with an
alkaloid-binding clay. (My comment: we have not met plant alkaloids
yet; we will see their plant kingdom distribution and medical
significance when we get to rainforest pharmacology.)

California Native American Indians harvested acorns as a major staple
in their diet. Before contact, they routinely burned the forest
undergrowth to encourage growth of the some twenty species that they
exploited in their environment. To make the acorns edible, the
naturally occurring tannic acid had to be removed. This was done by
soaking the whole acorns in a running stream or percolating water
through ground acorn flour. Another technique was to mix the acorn
flour with a clay that reduced the tannic acid content by up to 77
percent. They achieved this know-how by trial and error. We can verify
its efficacy today with chemistry.

Geophagy is especially popular with pregnant and nursing mothers, who
have an increased need for minerals (and mineral supplements). In
Zambia and Zimbabwe the main sources of soil, which 90% of rural women
consume while pregnant are giant termite mounds that also attract cows
and giraffes. When asked why, they might answer "I feel good when I
eat it" or "I like the taste." This doesn't answer the question for us
with a physiological perspective, but craving for trace elements may
be the reason for eating--dirt!

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NUTRIENTS
http://geography.about.com/cs/culturalgeography/a/geophagy.htm
Geophagy - Eating Dirt / A Traditional Practice Which Provides
Nutrients to the Body
BY Matt Rosenberg / filed in: Cultural Geography

People around the world eat clay, dirt or other pieces of the
lithosphere for a variety of reasons. Commonly, it is a traditional
cultural activity which takes place during pregnancy, religious
ceremonies, or as a remedy for disease. Most people who eat dirt live
in Central Africa and the Southern United States. While it is a
cultural practice, it also fills a physiological need for nutrients.

In Africa, pregnant and lactating women are able to satisfy the very
different nutritional needs of their bodies by eating clay. Often, the
clay comes from favored clay pits and it is sold at market in a
variety of sizes and with differing content of minerals. After
purchase, the clays are stored in a belt-like cloth around the waist
and eaten as desired and often without water. The "cravings" in
pregnancy for a varied nutritional intake (during pregnancy, the body
requires 20% more nutrients and 50% more during lactation) are solved
by geophagy.

The clay commonly ingested in Africa contains important nutrients such
as: phosphorus, potassium, magnesium, copper, zinc, manganese, and
iron. The tradition of geophagy spread from Africa to the United
States with slavery. A 1942 survey in Mississippi showed that...

at least 25 percent of the schoolchildren habitually ate earth.
Adults, although not systematically surveyed, also consumed earth. A
number of reasons were given: earth is good for you; it helps pregnant
women; it tastes good; it is sour like a lemon; it tastes better if
smoked in the chimney; and so on.*

Unfortunately, many African-Americans who practice geophagy (or quasi-
geophagy) are eating unhealthy material such as laundry starch, ashes,
chalk and lead-paint chips because of psychological need. These
materials have no nutritional benefits and can lead to intestinal
problems and disease. The eating of inappropriate objects and material
is known as "pica."

There are good sites for nutritional clay in the Southern United
States and sometimes family and friends will send "care packages" of
good earth to expectant mothers in the North. Other Americans, such as
the indigenous Pomo of Northern California used dirt in their diet -
they mixed it with ground acorn; this neutralized the acid.

* Hunter, John M. "Geophagy in Africa and in the United States: A
Culture-Nutrition Hypothesis." Geographical Review April 1973:
170-195. (Page 192)

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DIRTY EATING FOR HEALTHY LIVING
http://cogweb.ucla.edu/Abstracts/Diamond_99.html
BY Jared M. Diamond / Nature 400, 120 - 121 (1999)

As babies, we are warned by our mothers not to eat dirt, but as adults
some of us do it anyway and dignify it with the name of geophagy. The
regular and intentional consumption of soil, by itself or mixed with
food, has been recorded from traditional human societies on all
continents, especially among pregnant women1-4. Geophagy has also been
documented in many species of mammals, birds, reptiles, butterflies
and isopods, especially among herbivores5-9. Why do they and we do it?
Proposed biological functions of geophagy have now been tested by
James Gilardi and co-workers10, who uncover a fascinating evolutionary
arms race between plants and their would-be animal consumers.

The dirt-eaters studied were Peruvian Amazon rainforest parrots, of
which a thousand or more individuals of 21 species gather early each
morning at certain sites with exposed bare soil on river banks or
cliff faces. Because these sites are ideal for viewing and
photography, they attract 4,000 bird-watching tourists each year,
support 500 jobs in the local ecotourism industry, and earn Peru about
US$1,000 per year per individual wild macaw. The birds' taste in dirt
is highly specific: for instance, they congregate not just at one
particular bend of the Manu River but at one soil band running
hundreds of metres horizontally along that bend, spurning the dirt in
bands one metre above or below the preferred band. Gilardi et al.
tested possible functions of geophagy by comparing the physical and
chemical properties of soil samples from the preferred and rejected
bands.

The commonest explanation for geophagy in birds is to provide grit8.
Because birds lack teeth, many ingest pebbles or coarse soil with
which to grind food in their gizzards. Preferred particle sizes of
grit increase with bird size, from 0.5 mm for sparrows to 2.5 cm for
ostriches. However, Gilardi et al. found that the soil preferred by
Peruvian parrots is very fine: only 5% of it by volume is coarse sand
exceeding even 0.05 mm in particle diameter. Most of it is clay less
than 0.2 m in particle diameter, and preferred soils contain only a
quarter as much coarse sand and nearly twice as much fine clay as
rejected soils. So parrots are not eating soil to get grit. On
reflection, this is not surprising: parrots have no need for grit
because their strong, sharp bills can shred the hardest nuts.

A second function of geophagy, suggested for livestock, wild
ungulates, rabbits, butterflies and pregnant women, is to provide
essential minerals6,7. Soils sold in Ghanaian markets to pregnant
African women are richer in iron and copper than the dietary
supplement pills made by pharmaceutical companies specifically for
prenatal use. But Gilardi et al.10 found that soils preferred by
parrots contain lower available quantities of most biologically
significant minerals than non-preferred soils, and much lower
quantities than the parrots' preferred plant foods. Hence, unless the
parrots are making a big mistake in their taste preferences, they are
not selecting soils for mineral content.

A third function of geophagy, proposed for ungulate livestock, is to
buffer the rumen contents6. Because parrots lack a rumen, it will come
as no surprise that their preferred soils have no more buffering
capacity than distilled water.

What, then, do the parrots actually gain from ingested soil? It turns
out that they regularly eat seeds and unripe fruits whose content of
alkaloids and other toxins renders them bitter and even lethal to
humans and other animals. Because many of these chemicals are
positively charged in the acidic conditions found in the stomach, they
bind to clay minerals bearing negatively charged cation-exchange
sites2,3,5,9. That's why experienced tourists visiting destinations
with poor sanitation carry medicines such as kaopectate (high in clay
minerals) to adsorb the toxins. That's also why peasant farmers and
hunter-gatherers throughout the world often mix bitter but otherwise
nutritious plant foods (like acorns and wild potatoes) with selected
soils before consumption1-3.

Peruvian parrots behave like sophisticated human tourists and hunter-
gatherers. Their preferred soils were found to have a much higher
cation-exchange capacity than adjacent bands of rejected soils --
because they are rich in the minerals smectite, kaolin and mica. In
their capacity to bind quinine and tannic acid, the preferred soils
surpass the pure mineral kaolinate and surpass or approach pure
bentonite. Clearly, parrots would be well qualified for jobs as mining
prospectors.

Gilardi et al. confirmed this hypothesis with two sets of bioassays.
First, they exposed brine shrimp (the toxicologist's test animal of
choice) to extracts of seeds routinely consumed by macaws. Many of the
brine shrimp died, confirming the toxicity of the parrots' diet. But
mixing the solutions or extracts with soil preferred by parrots
reduced the effective toxin loads by 60-70% and improved shrimp
survival. Second, Amazon parrots were given an oral dose of the
alkaloid quinidine with or without preferred soil, and quinidine
levels were measured in the parrots' blood for three hours as
absorption took place from the gut. Providing soil along with the
quinidine reduced absorbed quinidine blood levels by 60%.

What is the evolutionary significance of plant toxins and animal anti-
toxin behaviour? From a plant's evolutionary perspective, a seed
should be high in nutrients to support germination and seedling
growth; the ripe fruit around the seed should also be nutrient-rich
and attractive to animals, encouraging them to pluck and eat the fruit
and disperse the seed. On the other hand, the seed itself should be
repulsive to animal consumers, inducing them to regurgitate or
defaecate it, and the unripe fruit should be repulsive, lest animals
harvest it before the seed is viable. From an animal's evolutionary
perspective, an ability to defeat the plant's toxin defences would
enable it to obtain the nutrients in the seed as well as those in the
ripe fruit, and to outcompete other animal consumers by harvesting the
fruit while it is unripe and still unpalatable to them.

Any textbook of animal biology describes the resulting evolutionary
arms race, in which plants evolve increasingly potent toxins (such as
strychnine and quinine), and animals evolve increasingly potent means
of detoxification. While enzymatic detoxification has previously
received the most attention, the work of Gilardi et al.10 and the wide
distribution of geophagy among animal herbivores suggest an additional
important means of detoxification by adsorption on ingested soil
minerals.

A host of interesting questions now comes into focus. How do parrots
discover the best soils -- can they discriminate among soils
immediately by texture and taste, or must they experiment with various
soils mixed with toxic food and discover which soil assuages their
upset stomach? Might the availability of suitable geophagy sites limit
herbivore distributions and merit concern from conservation
biologists? Only certain species of local herbivores are reported as
visiting geophagy sites: why? To return to our youthful dirty habits,
do curious dirt-licking babies deserve our encouragement for their
experiments with self-medication?

CONTACT
Jared M. Diamond
http://www.geog.ucla.edu/people/faculty.php?lid=3078&display_one=1&modify=1
email : jdia...@geog.ucla.edu

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FIRST WORLD DIRT
http://www.newscientist.com/channel/health/dn13587-soil-ultrabugs-thrive-on-a-diet-of-antibiotics.html
Soil 'ultra-bugs' thrive on a diet of antibiotics
BY Ewen Callaway / 03 April 2008

Call them the "ultra-bugs" – bacteria that are not merely resistant to
antibiotics, but feed on them. They lurk in dirt from parks, farms and
gardens. While the ultra-bugs don't normally cause disease,
researchers are concerned the bacteria might pass drug resistance onto
their deadly kin. Unlike antibiotic-resistant bacteria, such as MRSA
and XDR tuberculosis, which grow on other food in the presence of the
drugs, the soil bacteria can subsist on a diet of antibiotics alone.
The ability is akin to a person thriving on a diet of snake venom.

While hunting for soil bacteria that can turn plant waste to biofuels,
a team of microbiologists led by George Church of Harvard University,
Boston, Massachusetts, decided to grow soil samples in pure
antibiotics as a control. "We expected not to find a lot of bacteria
that could eat antibiotics for breakfast," says Church. "We were kind
of surprised."

Multiple resistance

To make sure the discovery was not a fluke, his team collected more
dirt from farms, forests and parks around the northeast United States
and Minnesota. All the soil samples contained bacteria that can
survive on antibiotics, and many subsisted on multiple drugs, he says.
Not only could the soil bacteria live on older antibiotics that many
bacteria have developed resistance to, such as penicillin, but they
could digest modern-day silver bullets as well, including
ciprofloxacin.

Many of the bacteria were found to be impervious to the bulk of
antibiotics, although they often could not grow without alternative
food sources. "They are resistant to virtually all antibiotics," says
microbiologist Morten Sommer, also at Harvard. Among 75 strains the
team tested, half were resistant to clinical doses of 17 of 18
antibiotics. That trait is particularly worrisome, says Sommer. Though
none of the bacteria normally cause human disease, many are close
relatives of pathogenic strains.

Spreading genes

For instance, Church's team found numerous species of Pseudomonas
bacteria, relatives of a microbe that infects people with cystic
fibrosis and burns. And two-fifths of the bugs isolated were related
to Burkholderia, a pathogen considered a potential bioterror weapon.
The soil bacteria could pass the genes for antibiotic resistance and
metabolism onto pathogens, says Church. In unpublished experiments, he
found that the bugs can spread drug resistance to harmless lab strains
of E. coli. "If the genes are out there to metabolise these wonder
drugs, I think that's something we should be aware of and be cautious
of," says Gerry Wright, a microbiologist at McMaster University in
Hamilton, Ontario, Canada. He suspects that much of the antibiotic
resistance seen in hospitals originates in soil.

But the finding also offers reason for optimism, says Stuart Levy, a
microbiologist at Tufts University in Boston. Soil bacteria have been
locked in a bioweapons arms race for billions of years, and have
developed the ability to feed on each others naturally occurring
antibiotics. If you take these bacteria into the lab and stop them
from eating each other's weapons, says Levy, levels of these novel
antibiotics should build up, and we may be able to extract them for
clinical use.

Journal reference: Science (DOI: 10.1126/science.1155157)

RESEARCHERS
http://arep.med.harvard.edu/gmc/
http://www.science.mcmaster.ca/biochem/faculty/wright/
http://www.tufts.edu/med/microbiology/faculty/levy/

BACTERIA
http://en.wikipedia.org/wiki/Burkholderia
http://www.newscientist.com/channel/opinion/mg19225725.000-biodefence-special-fortress-america-.html

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EATING DIRT AND ITS REASONS
http://www.cdc.gov/ncidod/eid/vol9no8/03-0033.htm
BY Gerald N. Callahan / 2003 Aug

Please
This earth is blessed
Do not play in it

- Sign on the wall of El Santuario de Chimayo, New Mexico

This place feels old beyond human recollection. The carvings and
paintings were surely done by human hands, but no one remembers whose
hands those were. The work is striking, especially in the apse behind
the altar. There, the colors of surrounding hills have been
transferred onto nearly luminous wooden reredos full of Catholic
symbolism. Above the altar hangs a most intricate ancient Christ
crucified on a green cross. Overhead, the roof is held in place by
massive carved wooden beams, big around as human bodies and blackened
by nearly two centuries of incense and candle smoke. The air is rich
with the memory of thousands of benedictions and baptisms. Threadbare
trousers have polished the pews to a high varnish that this afternoon
ripples with a low orange glow from dozens of votive candles burning
purposefully in back of the church.

This is El Santuario de Chimayo, an old adobe-brick and stucco
structure in the hills of northern New Mexico. This chapel was built
in 1816, but a sanctuary has been at this site for much longer. The
locals offer many legends about its origins, fanciful tales of
miraculous crucifixes and Santo Niños. But the truth is buried beneath
the murk of time. One thing is clear though, as beautiful as the
sanctuary is and as striking as the crucifix (El Sefior de Esquipalas)
above the altar is, nearly none of those in the pews today have come
to see the sanctuary or the crucifix. Instead, they have come from all
over the world to this place in New Mexico to eat the dirt that lies
beneath the adobe floor.

According to legend, that dirt is sacred, consecrated by Christ
himself. Crutches cast off by the newly healed fill the anteroom, and
on some days, the line of pilgrims stretches for blocks. Some call
this place the Lourdes of America, but in Chimayo the miracle can be
seen each day by anyone who peers into a low-ceilinged room off the
main entrance. There, a hole (the posito), half a meter across,
pierces the floor. Beside it, someone has left a plastic spoon to aid
the faithful. Beyond the spoon, beneath the opening, lies only dirt,
only the deep-red dirt of Chimayo.

Most of the faithful here today have come to eat that dirt. This
religious tradition is practiced, as far as I know, only at one other
place—a Catholic shrine in Esquipalas, Guatemala. But pilgrims to
these shrines are not the only humans who eat dirt. Nor are religious
reasons the only reasons to imagine that dirt may have special powers.

Geophagy (Eating Dirt) and Its Reasons

Other than water, what little stuff we humans have inside us is
largely dirt. Admittedly, this dirt is sometimes highly processed
before we receive it, but most solids that make up humans and other
creatures either are now or recently were dirt (the simple stuff that
stripes the outer surface of our world, the thin paste that raises us
above rocks) transformed by sunlight into plants or animals. Most of
us prefer the dirt we eat in the form of cows and sheep and carrots
and squash and bison and sorghum. Other dirt we’d just as soon scrape
from our feet and leave at the door.

But not everyone wishes to be so far removed from the stuff of mud
pies and mucilage. On every continent (except, possibly, Antarctica),
some of us intentionally eat dirt, and we are joined in this practice
by a myriad of rats, mice, mule deer, birds, elephants, African
buffalo, cattle, tapirs, pacas, and several species of primates (1).
Most scientists consider animal geophagy “normal,” probably because
most soil consumption by animals has no obvious adverse effects and is
sometimes beneficial (2); however, some of these same scientists
consider most (or all) human geophagy “abnormal.”

Abnormal Behavior

In the United States, many of us believe that humans should only eat
food. We consider the consumption of nonfood items pathological, even
though we know that what people define as “food” varies dramatically
by region and ethnicity. We call the pathological act of eating
nonfood items pica. Pica is a disease, but a disease different from
polio or smallpox. No infectious agent is obviously associated with
pica. Pica is a disease only because we believe normal “undiseased”
persons would not eat anything but traditional human foods; some of
those who do, some of the time, are at considerable risk because of
their unusual appetites.

Pathological consumption of soil, “soil pica,” is associated with
several psychological abnormalities. But all ingestion of soil is not
soil pica. How much soil a person has to eat to be considered ill is
not known. One report described soil pica in a developmentally
disabled person who regularly consumed more than 50 g of soil per day
(3). Most of us would consider that level of geophagy at least
potentially pathological, although I am not sure why.

In June 2000, the U.S. Agency for Toxic Substances and Disease
Registry appointed a committee to review soil pica. The committee
settled on pathological levels as consumption of more than 500 mg of
soil per day but conceded that the amount selected was arbitrary (3).
Soil consumption is defined as pathological according to the amount
eaten (no normal person could possibly eat that much dirt) and the
severity of health consequences (lead poisoning, parasites). Because
underlying psychological or biologic abnormalities are not easy to
establish, I explore only what appears to be nonpathological dirt
eating in pregnant women (especially in sub-Saharan Africa), migrants
from sub-Saharan cultures to other parts of the world (notably the
United States), and children worldwide.

Inadvertent Exposure

Why is it, that in spite of all the times we’ve been told not to, we
still eat dirt? This is a very complex question with many possible
answers. And while each proposed answer has its advocates, no single
answer seems satisfactory to all—except one. Almost everyone agrees on
one cause of geophagy, inadvertent consumption of air-, water-, and
foodborne dirt. Contaminated food, soiled hands, and inhaled dust add
soil to our diets. Children ingest considerable amounts of soil in
these ways. My children did. Of course, my children also ate dirt on
purpose. But child or adult, each of us inadvertently eats a little
dirt every day. This dirt can pose a health threat, especially near
sites of industrial contamination, but dirt we eat intentionally poses
a greater challenge. Intention may indicate something biologic that
drives some of us (sometimes regularly, sometimes religiously,
sometimes ritually) to eat dirt.

Tradition and Culture

For centuries, indigenous peoples have routinely used clays
(decomposed rock, silica and aluminum or magnesium salts, absorbed
organic materials) in food preparation. The clays were used to remove
toxins (e.g., in aboriginal acorn breads); as condiments or spices (in
the Philippines, New Guinea, Costa Rica, Guatemala, the Amazon and
Orinoco basins of South America); and as food during famine (4). Clays
were also often used in medications (e.g., kaolin clay in Kaopectate).
But the most common occasion for eating dirt in many societies (the
only occasion in some societies) is pregnancy. When sperm and egg
collide, the world changes. That is obvious. But why pregnant women
eat dirt is not.

Wiley and Katz (5) have proposed that eating clay serves different
purposes during different periods of pregnancy, soothing stomach upset
during morning sickness in the first trimester and supplementing
nutrients (especially calcium) during the second and third trimesters,
when the fetal skeleton is forming. This type of geophagy occurs most
commonly in cultures of sub-Saharan Africa and their descendants (5).
The timing of dirt ingestion and amounts consumed vary with tribes and
individual persons, but soil comes consistently from certain sites. In
some cultures, well-established trade routes and clay traders make
rural clays available for geophagy even in urban settings. Clays from
termite mounds are especially popular among traded clays, perhaps
because they are rich in calcium (5). Whatever the underlying reason,
geophagy in Africa does not appear to be a recent cultural
development; it may predate Homo sapiens.

Women eat dirt during the first, second, or third trimester or
throughout pregnancy (5), often throughout the day, as a supplement
rather than a meal. Most commonly consumed are subsurface clays,
especially kaolin and montmorillonite (5), 30 g to 50 g a day
(sometimes much more) (3). However, eating dirt is not always confined
to pregnant women, even among the cultures of sub-Saharan Africa (4),
nor is it limited to tribes with little or no access to dairy-derived
calcium (5), so these hypotheses do not adequately explain local
tastes for dirt.

Soil, including kaolinitic and montmorillonitic clays, contains
considerable amounts of organic material, including many live
microorganisms. The human gut is the largest area of direct contact
between a person and the world. Gut-associated lymphoid tissue (GALT)
is a major site of T-cell differentiation and selection in adults and
of intense immunologic activity (including T lymphopoiesis) in
children and adults (6–9). And while it is not entirely clear why some
gut-introduced antigens promote tolerance of microorganisms and others
immunize against them (10), it is clear that immunization via the gut
is a major source of immunoglobulin (Ig) A, both locally and
systemically (6–10).

Regular consumption of soil might boost the mother’s secretory immune
system. Monkeys that regularly eat dirt have lower parasite loads (1).
In some cultures, clays are baked before they are eaten, which could
boost immunity from previous exposures. For decades we have used
aluminum salts, like those found in clays, as adjuvants in human and
animal vaccines. Adjuvants are compounds that nonspecifically amplify
immune response, probably because of their effects on innate defenses
such as macrophages, dendritic cells, and the inflammatory response.
Aluminum compounds make effective adjuvants because they are
relatively nontoxic, the charged surfaces of aluminum salts absorb
large numbers of organic molecules, and macrophages and dendritic
cells readily phagocytose the particulates produced by the combination
of the adjuvants and the organic compounds (11). The clays that
pregnant women and others consume, which are rich in aluminum
compounds, likely make at least passable immunologic adjuvants. For
all these reasons, clays might act as vaccines. And the IgA antibodies
produced against the associated organic antigens may appear in breast
milk and have a major role in mucosal protection of newborns.

In pregnant women, this type of gut immunization might produce high
levels of IgA against endemic pathogens and other antigens. All this
IgA would appear shortly before birth in the breast milk and would
provide protection for infants against precisely the pathogens
encountered immediately after birth. Furthermore, IgA antibodies
prevent attachment of bacteria and some viruses at mucosal surfaces
(12), the major contact between the infant and the infectious world.
In humans, mucosal surfaces offer the only routes of natural
immunization short of wounding, and dirt would seem to offer a potent
vaccine containing many endemic pathogens—no needles, no sugar-cube,
no gene gun.

Eating dirt, then, rather than being abnormal, may be an evolutionary
adaptation acquired over millennia of productive and not-so-productive
interactions with bacteria—an adaptation that enhances fetal immunity
and increases calcium, eliminates gastric upset, detoxifies some plant
and animal toxins, and perhaps boosts mothers’ immunity at times when
the hormones of pregnancy (13), factors produced by the fetus (14),
changes in the complement system, replacement of MHC class I antigens
in the trophoblast (15), and who knows what else suppress the mother’s
natural immunologic desire to destroy her fetus—a miracle, nearly.

Innate Tendency

My children ate dirt with surprising gusto, garden soil, road soil,
leaf-mush soil, sod soil, bug-body soil—even gutter soil. As usual
with my children, before I could talk them out of this behavior, they
gave it up on their own—their behavior depending more on personal
likes and dislikes than on my paternal concerns. I was pleased when
they quit. Later I was reassured to discover from other parents that
their children were just as taken with dirt as mine, some even more
so. I felt less like the parent of a couple of dirt-eating, psychosis-
ridden, nutritionally deprived children, even if my children were
never quite “normal.”

Eating dirt appears nearly universal among children under 2 years of
age. When I asked my 2-year-old daughter why she ate dirt, she just
stared at me, her eyes wide open, a thick moustache of loam limning
her lips. She must have decided that either what I had asked was
unfathomably abstract or her answer would be far beyond my
comprehension.

Soil pica has been defined as eating 500 mg to >50 g of soil per day
(3). But the general applicability of these numbers is widely disputed
(pregnant women in Africa eat far more soil than this). By inference,
however, normal soil consumption must fall into the range of 0 mg to
500 mg per day per small mouth. Soils consumed by children may differ
from those consumed by adults. Generally, children consume topsoils
and not the deep (60 cm- to 90-cm deep) clays adults regularly consume
(5). And children are considerably less selective in the sites they
choose for dirt to eat. But why children eat dirt remains largely
obscure to all but children.

Children may eat soil for the same reasons pregnant women and some
animals do (2,4,16–18). Because of their rapid growth, they have
special nutritional needs and surface soils may serve as supplemental
nutrients; detoxification of plant or animal toxins might be
accelerated by geophagy— particularly in some parts of the world; or
soil components, especially clays, may relieve gastric distress. But
topsoils are probably not as effective as deep clays at gastric
soothing.

Among children, too, it seems eating dirt might have immunologic
consequences. Maternal immunoglobulins are secreted in breast milk
shortly before birth and for 1 year or more afterwards. Children often
begin eating dirt a year or two after birth. As maternal immunity
wanes, eating dirt might “vaccinate” children who are losing their
maternal IgA, which could stimulate production of nascent
immunoglobulins, especially IgA. Eating dirt might also help populate
intestinal flora.

But all of this remains speculative. No clear evidence supports a
biologic benefit to geophagy among children. Its frequency and
distribution, though, suggest a greater biologic involvement than the
simple oral obsessions of children.

Risks of Eating Dirt

How dangerous is eating dirt? My mother was pretty certain about this—
damn dangerous. Soils contaminated by industrial or human pollutants
pose considerable threat to anyone who eats them. Reports abound of
lead poisoning and other toxicities in children eating contaminated
soils. Similarly, we do not have to look farther than the last refugee
camp or the slums of Calcutta or Tijuana or Basra to find the dangers
of soils contaminated with untreated human waste. But the inherent
biologic danger of soil is difficult to assess. Soil unaffected by the
pressures of overpopulation, industry, and agriculture may be vastly
different from the soil most of us encounter routinely.

Using DNA-hybridization analyses, Torsvik et al. (19,20) found an
estimated 4,600 species of prokaryotic microorganisms per gram of
natural soil. Subsequent investigations, using more sophisticated
techniques, found even more species (20), 700–7,000 g of biomass per
cubic meter of soil. Soil is a considerable biologic sink, and
certainly some organisms found in it are pathogenic in humans. Yet
evidence of soil as a major cause of disease in humans and other
animals is limited. And many reported diseases are the result of an
abnormal situation, e.g., industrial pollution or untreated sewage.

Most infectious diseases acquired through eating dirt are associated
with childhood geophagy, which routinely involves topsoils rather than
deep clays. One recent report describes infection of two children at
separate sites with raccoon roundworm (Baylisascaris procyonis ) (21).
The infection resulted in severe neurologic damage to both children,
and one died. The roundworm was ingested along with soil in both
cases. Eating dirt can have dire consequences.

In the United States, the most common parasitic infection associated
with geophagy is toxocariasis, most often caused by the worm Toxocara
canis. Seroprevalence is 4% to 8% depending on the region, but
incidence of antibodies to T. canis is as high as 16%–30% among blacks
and Hispanics. The most common route of infection is ingestion of soil
contaminated with dog or cat feces (22). Even though, humans are only
paratenic hosts of T. canis, under some circumstances (though severe
cases are rare), the worm can cause considerable damage (visceral
larva migrans, ocular larva migrans, urticaria, pulmonary nodules,
hepatic and lymphatic visceral larva migrans, arthralgias) (22–24).
Toxocara eggs persist in soil for years. As with soils contaminated by
human wastes, soil consumption itself does not cause toxocariasis. And
studies of seroprevalence do not distinguish between infection and
immunization.

Among children in Nigeria, the most common parasitic infection
associated with eating dirt is ascariasis (25). Ascarid worms infect
as many as 25% of the world’s population (more than 1.25 billion). A
scaris lumbricoides is the most common worm. Asymptomatic in many
adults, infection is much more serious in children; intestinal
obstruction is the most common symptom. Because the worms do not
replicate in humans, reexposure is required to maintain infection
beyond 2 years. The correlation between geophagy and helminth
infection varies with different helminthes. Geissler et al. reported
correlation between geophagy and ascariasis (especially caused by A.
lumbricoides) and possibly trichuriasis but none between geophagy and
reinfection with Schistosoma mansoni, Trichuris trichiura, or hookworm
(26). All parasites that infest soil do not uniformly infect people
who consume dirt. Nor do all who eat dirt routinely contract disease.

Immunologic Development and Infectious Disease

Many nonhuman animals regularly eat dirt, generally without ill
effects and in many cases with some benefits. Even in humans, there
are few reports of infections routinely associated with geophagy by
pregnant women in sub-Saharan Africa, probably because women take
clays from 60 cm to 90 cm below the soil surface and, at least some of
the time, they bake the clays. But these factors seem inadequate to
fully account for the frequent absence of overt ill effects.

Helminth infections associated with geophagy appear to affect the
frequency of inflammatory bowel diseases, which occur most often in
industrialized nations. The underlying cause of these diseases may be
abnormal immune response to the contents of the gut or perhaps to the
gut itself (27). Inflammatory bowel diseases occur at much lower rates
in regions where helminth infections are common. Development of normal
gut-associated immune response may be aided by the presence of worms.

In studies of healthy mice, Trichinella spiralis prevented colitis
induced with tri-nitrobenzene sulfonic acid by redirecting a primarily
Th-1 response to a Th-2 response (28). Preliminary studies indicate
that helminth infection may also alter the course of inflammatory
bowel disease in humans (29). Soil is a rich source of parasitic
worms. Studies using a number of other animals have also, at least
indirectly, associated dirt and microorganisms with normal immunity.

The Environmental Protection Agency estimates that children in the
United States consume, on average, 200–800 mg of dirt per day. Some
children regularly consume more than their allotment. Still, that
doesn’t seem like a lot of dirt. We parents have tried for years to
put a stop to it. I don’t know of an instance in which anybody has
succeeded in keeping children away from dirt. But animals have been
successfully raised in absolutely sterile environments. Rabbits, mice,
guinea pigs, and rats have been raised under such conditions (30,31).
In each case, the immune system failed to develop normally. Lymph
nodes and GALT did not achieve the right shape or composition and
could not initiate normal immune response. Reexposure to infection
later in life does not work, at least not fully. There is a window
when infection drives the immune system toward its proper end. After
that, mice, rats, rabbits, and guinea pigs are at the mercy of the
microbial world.

Evidence suggests that the results would be the same in children. In
large families, children with many older brothers and sisters are less
likely to have asthma, hay fever, or eczema. West African children who
have had measles are half as likely to have allergies as children who
never had measles. Italian students who recovered from infection with
hepatitis A had fewer and less severe allergies than fellow students
who were never infected. Children with Type I diabetes (an autoimmune
disease) are less likely to have had infections before their fifth
birthdays than healthy children of the same age. Children raised in
rural areas, especially on farms, have fewer allergies and autoimmune
diseases than children raised in cities. All of these notions have
been referred to as the “hygiene hypothesis” (32).

Children exposed a little more to the infectious face of this world
seem to fare better as adults. I do not mean to say that vaccination
is inappropriate. Vaccination is, most often, infection, and
vaccinations have done more to improve childhood survival rates that
any other single bit of modern medicine. Nor are water purification
and sewage treatment inappropriate. Water and sewage treatment have
done even more than vaccination to eliminate disease in areas where
human populations have exceeded the ability of the local environment
to deal with human waste and the pathogens associated with it. But,
evidence indicates that infection early in life is critical for the
development of normal immune systems.

Exposure-dependent development is not limited to the immune system.
Animals, humans included, must be exposed to the sights, sounds, feels
tastes, and smells of this septic world. When we are not, our nervous
systems do not develop normally, do not rewire, expand, and contract
as they must to survive (33). For humans, as for rabbits, there is a
window in childhood when our experiences, our infections, change
everything, once and for all. Inside that window, infection causes
lymph nodes and GALT to enlarge and reorganize, to separate into
cortices and medullae, into primary lymphoid follicles, and develop T-
and B-lymphocyte–rich regions of immune competence destined to someday
be germinal centers, where our defenses will muster and the real
battle will be fought. This window is a defining moment, when the
simplest and lowest forms of life—the dirty, the infectious, the
parasitic, and the septic—alter who we are.

We do not know which childhood infections are most important, but
several studies implicate mycobacterial infections. A large group of
bacteria most of which cause no apparent disease, the mycobacteria,
have strains that cause serious diseases (e.g., tuberculosis,
leprosy). Mice injected with ovalbumin (the major protein in egg
white) become allergic to ovalbumin. But mice first infected with
mycobacteria and then injected with ovalbumin do not become allergic
(34).

Early infection of children with some mycobacteria may promote strong
immune systems, a normal sense of self, and a normal defense of that
self. Mycobacteria are found in large numbers in dirt. And animals
(probably including humans) kept from this dirt may lose the ability
to recognize certain dangerous organisms as a threat, lose the ability
to discriminate between self and not self, and lose the ability to
distinguish the fatal from the innocuous.

The “Age of Bacteria”

For more than 3 billion years, microorganisms, especially bacteria,
have ruled earth. As Stephen Jay Gould said, “We live now in the ‘Age
of Bacteria.’ Our planet has always been in the ‘Age of Bacteria’ ever
since the first fossils, bacteria of course, were entombed in rocks
more than three and a half billion years ago” (35). And bacteria have
done more than any other living group to alter the character of this
earth (36). It has been estimated that more than 1029 bacteria live on
this planet and as many as 1014 live on each one of us. Through all of
history, we humans have waltzed with bacteria and the rest of the
microscopic world. We had no choice. Bacteria outnumber, outweigh, out-
travel, and outevolve us.

That bacteria cause so many human diseases is not astounding. It is
astounding that so few bacteria cause human disease. Pathogenic
bacteria are merely the microscopic tip of the largest of all biologic
icebergs. How fortunate, we imagine. But fortune may have little or
nothing to do with our survival. Billions of years of confrontation
rather than luck were likely our benefactor. Through those
confrontations and those eons, nearly all of us learned to coexist
peacefully. Neither humans nor microorganisms benefit from fully
destroying the other. Fatal infections seem, biologically at least,
shortsighted. And even a brief course of antibiotics is enough to
remind us that a world without bacteria would be a poorer world. This
is not a war, as it has often been described, even though we have
mustered an impressive array of weapons—bactericidal cribs and
mattresses, toilet cleaners and counter tops, blankets, deodorants,
shampoos, hand soaps, mouthwashes, toothpastes. This is not a war at
all. If it were, we would have lost long ago, overpowered by sheer
numbers and evolutionary speed. This is something else, something like
a lichen, something like a waltz. This waltz will last for all of
human history. We must hold our partners carefully and dance well.

Chimayo

Here beneath the old wood crucifix, as I watch the faithful leave the
little chapel in Chimayo, I marvel with them at the miracle beneath
this adobe floor, the same miracle buried beneath most every place
human feet have trod.


-Dr. Callahan is associate professor of immunology/public
understanding of science in the Department of Microbiology,
Immunology, and Pathology at Colorado State University in Fort
Collins, Colorado. His research on immunity, infectious diseases, and
self-perception has been published in poetry and two books of creative
nonfiction in addition to scientific reports.

CONTACT
Gerald N. Callahan
http://www.cvmbs.colostate.edu/mip/people/faculty/callahan.htm
email : Gerald....@colostate.edu

.

http://www.cdc.gov/ncidod/eid/vol9no8/03-0033.htm
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