Plagues, Pestilences
and Diseases
2 August 2011 Last updated at 19:42 ET
Garden bird disease spreads to new parts of the UK
Daniel Boettcher By Daniel Boettcher BBC Correspondent
A virus affecting garden birds is spreading to new parts of the
UK, researchers are warning.
This form of avian pox causes lesions, often around the eyes and
beak.
The virus, affecting great tits, is believed to be a new and more
severe strain of a disease that has affected other bird species
for several decades.
When it was first found in the UK in 2006 it seemed to be confined
to south-east England, but has now spread further north and west.
The findings come from a team at the Zoological Society of London
(ZSL).
Researchers now want help from the public to help track any
further spread of the disease.
Avian pox can be spread through contaminated bird feeders, via
biting insects and through direct contact between birds.
It has been known in species including dunnock, woodpigeons and
house sparrows for many years.
The form now affecting great tits may be the same strain as one
discovered in central Europe.
Vulnerable to predators
Dr Becki Lawson, from ZSL, said: "What's different about this
avian pox in this species is that the lesions can be very severe.
"It's not unusual for several birds to be affected at one site.
"Initially the reports were restricted to south-east England,
chiefly in Surrey, Sussex and Kent.
"Over the last year we've seen the geographical range of this
disease spread quite significantly, as far west as Wiltshire and
as far north as Staffordshire."
In the most severe cases the lesions caused by the virus in great
tits can prevent the birds from feeding or flying and makes them
more vulnerable to predators.
ZSL has been working with Oxford University, the British Trust for
Ornithology and the RSPB. Researchers now want help from the
public to monitor suspected cases of the disease:
Dr Lawson said: "We're very keen to track further spread of the
disease this year as we progress into the months where we'd expect
to see a peak in the numbers of reports, in the late summer and
early autumn."