Testing Shelter Dogs for Levels of Titre Antibodies To Rabies
Article 23 that regulates conditions that animal shelters must adhere to prescribes keeping vaccinated dogs on observation in shelters for six months after receiving or testing for levels of rabies titre antibodies is illogical and unjustified for many reasons.
We asked for the opinion on the need for testing levels of rabies titre antibodies from a respected expert, Michael J. Day, a veterinary pathology professor. His answer is as follows:
The WSAVA (The World Small Animal Veterinary Association) guidelines for shelter vaccination suggest that the most appropriate protocol is to vaccinate dogs against rabies at the time they are released from the shelter (with two doses given in endemic areas).
The incubation period for clinical rabies in the dog is 3 - 24 weeks, so the 10 day period of quarantine (or for that matter the additional weeks) may not necessarily identify infected dogs... but the 10 day period is chosen where a dog may have been bitten by a suspected infected dog because the period of virus shedding before the onset of neurological signs in naturally infected animals is 1 - 5 days.
Serology is not routinely used to diagnose rabies infection as clinically infected dogs rarely have time to seroconvert. Serology is really only used to determine vaccinal immune response and seropositivity most likely indicates previous vaccination. However to quote from Greene:
"Testing dogs for serum antibodies to rabies virus to determine recent exposure to rabies virus can be ambiguous because elevated titres can result from vaccination or from past or recent exposure to virus. Therefore a serologic response can in no way be definitively differentiated from vaccination or infection."
Hope those comments are of some help.
Michael J. Day
BSc BVMS(Hons) PhD DSc Dipl ECVP FASM FRCPath FRCVS
Professor of Veterinary Pathology
School of Veterinary Sciences
University of Bristol
Michael J. Day is a veterinary pathology professor at School of Veterinary Sciences at Bristol University, author of textbooks Clinical Immunology of the Dog and Cat (now in its second edition) and Veterinary Immunology: Principles and Practice and numerous professional works. He is an active member of many professional organizations and winner of significant awards for his work in the field of animal disease research. You can find out more information about him at www.bristol.ac.uk/vetpath/cpl/mjd.htm.
By taking the above statement into consideration, one can conclude that by testing dogs for serum rabies virus antibodies can only determine whether or not the virus is present and not the origin of the virus, earlier vaccination, or rabies infection. So, the tests give us the immunisation record and not proof of disease. More on this subject can be found in the German language by clicking on these links: Gießener Justus-Liebig-Uni; Friedrich-Löffler-Institut.
Apart from the aforementioned questionable purposefulness and imprecision of testing levels of rabies titre antibodies as a method of determining rabies, it is remarkable that EU legislation does not regulate the obligation of shelters to administer testing for levels of rabies titre antibodies for dogs. No shelter in the world administers rabies titre antibodies tests, especially not in the EU. The controversial testing is done worldwide only in the event of animal border crossing - when animals enter our country from countries known to have a high risk of rabies. Since Croatia is categorized as a country free of urban rabies, there is no logic in ordering shelters to undertake the same measures as for animals from countries with high risk of rabies.
In the EU the only regulation that demands testing the levels of rabies titre antibodies is Regulation 998/2003, which concerns the non-commercial moving of house pets, and regulation 92/65/EEC, which applies to commercial movement. The condition that applies to dogs, cats, and pet ferrets that are being moved to the EU from other countries is that they have received the test for rabies titre antibodies at the latest 30 days after having been vaccinated against rabies and three months before the trip. Apart from that, EU legislation does not have any other requests for testing rabies titre antibodies.
In Croatia we vaccinate foxes orally and there are no records of an increase in rabies disease, and the last case of rabies in humans was noted in 1964. Even though the testing of rabies titre antibodies or six months observation of animals in shelters is prescribed in the current Regulations as of 2004, in the last eight years shelters in Croatia have not been carrying out the provision prescribed by Article 23 of the Regulations, nor had the veterinary inspection been asking for this because it is impossible to carry it out in practice. In the whole eight years during which the Regulation has been valid, and the aforementioned provision not carried out, there hasn’t been one documented case of rabies in dogs housed in a shelter!
There are many absurd and illogical facts: citizens can adopt a dog straight from the street and have him/her vaccinated and chipped at the vets, without checking for titre anti-bodies, however a dog that ends up in a shelter must go through the long winded procedure of staying at the shelter and being rehomed. Furthermore, a dog that's been adopted for example in Slovenia, can cross the Croatian border providing he/she has been vaccinated and micro-chipped, whilst a dog from a Croatian shelter, in order to be adopted, must also pass the titre test.
The implementation of the disputed article would signal the collapse of the rehoming system for shelters in Croatia, as due to the prescribed procedure dogs in the shelters must spend a minimum of 45 days there or 6 months if the testing is not carried out. We can expect streets full of abandoned dogs and cats that, apart from not being vaccinated against rabies, represent a danger due to the possibility of spreading disease, attacking people and other animals, and so on. It is clear that the purpose of this measure cannot be rabies suppression and citizen protection because cats don’t have to be vaccinated against rabies, even though all the statistics show that cats are the most common rabies transmitters.
The procedure prescribed by Article 23 of the Regulations, as well as the one in the proposal of the new Regulations is a financially unnecessary burden to shelters, local self-government units, and our state. In the fight against rabies it is sufficient to carry out a classic procedure in shelters: 10 days of quarantine, then vaccination of healthy animals and education of foster carers about rabies symptoms, importance of regular annual vaccination for animals against rabies, and the non-abandonment of animals. That kind of shelter operation and animal rehoming enables continued rehoming without overloading shelters or accumulating abandoned animals in the streets, which would cause the collapse of the rehoming system. The implementation of Article 23 of the Regulations demands high expenses from the shelters, which is especially problematic for a country such as Croatia, with a pronounced lack in the numbers of abandoned animal shelters, despite the fact that they have been prescribed as an obligation of the local community by the Animal Protection Act, but they haven’t been built precisely because of the large financial expense. The extended stay of dogs in shelters due to the demands from the Regulations significantly increases total expenses to the shelters, and finally does not lead to better rabies protection.