Bewteen 2000 and 2003 there was an epidemic of hamster polyoma virus infecion in the UK. We are very fortunate to have Dr Liz Johnson, a veterinary research graduate from Glasgow Veterinary School to advise and inform us. I have collected various articles from the hamster journals over this time and these are presented here. For the definitive guide, I suggest the reader refer to the article in the BHA journal January 2002
A commentary on the infection was received from Dr Aiden Foster from the Bristol School of Clinical Veterinary Science.
Articles on the virus have been published in recent BHA journals:
A Response to last month's internet gleaning on Papova by Liz Johnson
Lumps - a response by Joanna Roach
Papovavirus - an update by Anne Dray
Further information from the NetVet site has been submitted by Jessica Penther.
I have had some provisional results from Germany which are similar to previous in that there is some reactivity to the papovavirus antigens but not the main antigen. The tests are being repeated and when I get the final results I hope to draft an abstract for a conference and for publication. This still leaves us with no DEFINITIVE proof that the papovavirus is the cause of skin nodules or the spread of the disease.
In some respects the vet is correct in suggesting that we have to live with the situation.
Since the outbreaks behave like an infection one has to adopt the usual precautions of trying to limit the spread of any infectious disease. That is, try to reduce handling of affected or in-contact animals. Wash hands and use gloves between handling animals. Keep stocking densities low to avoid cross contamination via urine of the bedding and animals. Only the local vets can really comment on such measures because in part they are based on the knowledge of the individual hamster owner's accommodation.
If nothing else this problem has highlighted the need to secure a close working relationship with local vets to carry out (albeit potentially expensive) tests including skin biopsies and post-mortems to try to establish causes for skin nodules or sick animals. Not all nodules are going to be of the kind associated with papovavirus and without a histopathology report one can only speculate. Those hamsters that have fallen ill/died with such nodules may have disease unrelated to the suspected papovavirus.
Similarly if the pattern of the disease should change and the internal tumour form of the disease should be reported (called lymphoma) then we are potentially going to have deaths. Potentially whole colonies would need to be considered for euthanasia. This reflects the experience of research colonies where once established the diseases becomes endemic and there is no way of preventing spread.
Since urine is considered to be the source of the virus the showing of animals requires careful consideration of handling and hygiene.
Dr Aiden P Foster
Bristol School of Clinical Veterinary Science
We are now aware of 4 Hamsteries that have almost certainly been infected by a highly infectious virus called a papovavirus. We did believe that the original notification that we received of the occurrence of this virus in the West Country was an isolated case but the other suspected cases are in the Midlands and the Yorkshire Areas.
The infection has been associated with the development of skin nodules that look like warts. The nodules are found particularly around the face but may involve the whole skin of hamsters. The limited information that we have to date is that the virus is transmitted via urine. This means that it can be spread by cage litter being kicked out into other cages, the same scrapers being used, handling several hamsters without washing hands or wearing gloves, etc. We understand that this virus is specific to Syrian and European Hamsters and that other species of hamsters or other animals are unaffected and cannot carry the virus.
Historically the virus has been associated with internal tumours (lymphoma). The lymphoma may take 5-30 weeks to develop following infection. The lymphoma disease is usually fatal. Please note that the case material from the West Country has not been associated with the lymphoma form of the disease.
Affected animals in the more advanced stages of the disease show warts around the face but earlier in the progression of the disease if the skin on the scruff of the neck is rubbed between the fingers then small grains can be felt whereas normally nothing is felt. Unlike true papillomas (warts) the skin lesions do not appear to regress, and there is no evidence, to date, to support the use of wart vaccines.
The case material seen in the West Country is the subject of on-going studies with the local vets and a research group in Germany. They are attempting to confirm that papovavirus is involved in this disease.
Them is no information about effective treatments and papovavirus infection can become endemic within a colony. Until we have better information about how to avoid the spread of this disease we would urge members to minimise the movement of stock and particularly ask members who have not imported new stock to their hamsteries or attended shows since last summer to please keep their stock isolated for the time being.
If anyone believes they have affected stock it would be very helpful if they could contact myself to register this fact and for them to advise anyone that has had stock from them. We need complete honesty about the extent of this disease if we are to prevent It becoming widespread.
(published in 2000)
Publication Date unknown - more information may be available at www.netvet.com
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