Passports, tiny worms and herbal teas on the web

摘要

A pilot scheme to allow cats and dogs from the UK to visit specified Western European countries puzzled some contributors to the ProMed mail discussion group: 'The animals must be injected with an identifying microchip, vaccinated against rabies, blood-tested and issued with a certificate. They must also be checked by a veterinarian in the country they visit and vaccinated against tapeworm and ticks not more than 48 hours and not less than 24 hours before returning to Britain'. Paul Mason, a parasitologist from Dunedin, New Zealand, knew of a vaccine against Echinococcus granulosus, but not of any against other tapeworms of dogs or against ticks. What does it all mean? The moderator then listed some parasitic infections that dogs can transmit to humans, eg. Toxocara canis, T. cati, Trichuns vulpis, Ancylostoma braziliense, A. caninum, Uncinaria stenocephala, Taenia (Multiceps) multiceps, and Strongyloides stercoratis. Dogs can form reservoirs of Dirofilaria immitis and Leishmania, transmitted to humans by arthropods. However, said Simon Parker (National Institute of Biological Standards and Control, UK), for 'vaccination' read 'treatment', specifically praziquantel treatment against the fox tapeworm Echinococcus multiloculans and an acancide against the tick Rhipicephalus sanguineus (see Department of Health Website at http://www.doh.gov. uk/memorandumonrabies/ and more at http://www.maff.gov.uk/animalh/quarantine/). James Allan from Pfizer explained that E. muttiloculans is endemic in France, Germany, Switzerland and Austria, but not in the UK. Over the past 20 years, it has killed more people in those countries than rabies. It is extremely dangerous to humans (foxes harbour the adult, intestinal stage, rodents harbour the larval stage) as dogs and cats can become infected by eating infected rodents and pass on the eggs in their faeces. The larval stage then develops in the human liver and is difficult to treat - 'lobectomies and liver transplants are used in several EU countnes'. Echinococcus granulosus, on the other hand, is already endemic in the UK, for instance, in the Brecon area of Wales. As for vaccines, Peter Schantz (Centers for Disease Control, Atlanta, GA, USA) said that scientists in Australia and New Zealand have developed one to protect sheep and cattle against E. granulosus, but not yet one for dogs, although praziquantel treatment is highly effective. Roger Clarke, a vet from Australia, asked 'Why not just have mandatory antihelminthic treatment at suitable intervals before travel?