The Prophylactic Vaccination of Dogs against Rabies
Prophylactic vaccination of dogs in communities where outbreaks of rabies exist is predicated on the reduction of the susceptibility of dogs in that area to the disease. If rabies vaccines, for example, are only a certain per cent effective, it could be assumed that, depending on the number of dogs vaccinated, the number of susceptible dogs would be decreased by that percent. The fewer the susceptible animals, the fewer the number of animals that would become infected and the less chance the disease has for spreading.
The magnitude of a rabies-control programmed in this country isrealised by the committee. Rabies has flourished in many parts of the country for years, and we may be faced with factors and problems which have not been apparent in other countries where the disease has appeared only for a short time and then has been eradicated. Rabies vaccines may well play an important role in a well-regulated control programmed. As an example of the probable value of the use of vaccines in controlling rabies, a recent article comes to attention from Hungary concerning a report on rabies which has been in evidence in that country for many years in spite of vigorous measures for its control. It has been only in the past few years when compulsory prophylactic vaccination was instituted in certain areas that the disease has been reduced to a minimum. In this case, of course, vaccination was only an added means of control, the other sanitary policy measures being vigorously pursued at the same time.
The committee states emphatically that the use of rabies vaccines alone, no matter how effective, cannot control the disease, but that such vaccines can be used to advantage in some communities and under certain conditions in conjunction with other standard measures. The State-wide compulsory vaccination of dogs is not considered advisable as practiced at the present time. Its compulsory use in restricted communities should be approached with caution and only on a sound basis of administration.
In the report of the same committee for 19404 the following information concerning the control of rabies is given:
It is realized that it is not possible at this time and in the present state of rabies control in the various States to prescribe hard and fast regulations, since local conditions, with particular reference to the presence or absence of rabies, may make it advisable to modify certain of the regulations. The following proposed regulations, therefore, should be considered in this light:
1. All dogs shall be licensed annually. The fee shall be at least$1 for a male, $1 for a spayed female, and $2 for an unspayedfemale.
2. The license tag issued when the dog is licensed must be affixed to the collar of the dog and worn at all times when the animal is on public property.
3. All unlicensed dogs or dogs not wearing license tags shall be either humanely destroyed or impounded and disposed of as follows: Animals shall be kept 48 hours (or 72 or 96hours) and if not claimed within that time shall be humanely destroyed. If an animal is claimed by its owner and has not been licensed, such a dog may be returned to the owner upon the payment of a license fee and a collection and maintenance charge of $2. A licensed dog claimed shall be returned to the owner upon payment of $1 collection charge. (In this connection it may be advisable to assess a penalty against the owner of the dog for violation of the dog regulations. It is also well to consider the possibility of rabies being spread through the return of impounded dogs to their owners and through the practice of selling dogs from the pound. Serious consideration should be given to these points, but they probably can best be handled as local conditions warrant.)
4. A sufficient full-time personnel shall be available to properly control stray dogs and unlicensed dogs as provided above.
5. In the event that rabies is reported or suspected in a dog, it shall be the duty of the official in charge to have definitely determined whether or not the animal is rabid. In the event that rabies is established, a thorough inquiry should beamed immediately insofar as possible into the movements of the rabid dog so that all dogs known to have beep bitten by or exposed to the rabid dog may be destroyed or kept in quarantine or otherwise treated as hereinafter provided. Quarantine of at least 60 days shall be placed over an area covering the possible movements of the said rabid dog. This quarantine shall provide that all dogs be kept on the premises of the owner, or, when upon public property, shall be held on a leash not over 6 feet long in the hands of competent person.
Dogs not definitely known to have been bitten but which have had contact with a rabid dog may be kept in strict quarantine on the premises of the owner for a period of knotless than 6 months. Such an animal in addition may be given a series of vaccination treatments by a qualified veterinarian. In this event the quarantine period may be reduced to 2 months. Dogs may not be removed from the quarantined area without specific permission from the constituted authority.
6. Funds: There shall be ample funds available for immediate use at all times for the proper carrying out of these regulations. These funds shall be consistent with the size of the community. In addition to this, there shall be set aside assume of money for the specific purpose of controlling outbreaks of rabies as they might occur. This money shall be available at all times and shall not be used for any other purpose than controlling such outbreaks. This money might come from regularly appropriated State funds labeled for this specific purpose or from dog-tax revenues or from any source that seems consistent with procedures in the State. In any event, it shall be available at all times in sufficient amounts to meet any expected need.
7. Personnel: Since rabies is an animal disease, the veterinary profession shall be represented in the personnel concerned with the control of the disease. The control of rabies in astute shall be fixed in an authority with power to work inane section of the State and to call for such local cooperation as may be feasible or desirable. In outbreaks in communities, due notice of such outbreak and quarantines that might be imposed shall be given publicity and in all possible ways brought to the attention of the public at large and the dog owner in particular.
8. Vaccination: When thought advisable or desirable, prophylactic vaccination of dogs may be encouraged or advocated on a voluntary basis. Vaccinated dogs, however, shall not enjoy any special privileges because of such vaccination, since vaccination is considered to be only an adjunct in any programmed for the control of rabies.
9. The authority in the State charged with the control of rabies shall notify the authorities in the several States of outbreaks of rabies and their location as they occur; together with the date or dates the quarantine is lifted. All transportation companies in a State shall be notified of outbreaks of rabies and the quarantine regulations imposed governing such outbreaks.
Vaccination of Dogs against Rabies
Vaccination against rabies dates back to the work of Pasteur, and the method for persons exposed to the disease (the Pasteur treatment) has been in use many years, but its use is limited to human beings. It consists of a number of daily injections of a specially prepared vaccine. In recent years several modifications of Pasteur’s vaccine have been in use, and good results have been reported. These methods have also been applied for years to dogs and other animals following exposure to the disease.
In 1921 the single-injection prophylactic vaccination (the one-shot method) against rabies was described by two Japanese investigators, Amino and Doe, and was introduced into this country by Eichhorn and Lyon in 1922. This type of vaccination has for its purpose the development of immunity in dogs previous to exposure to rabies infection. Although measures are available for the control of rabies without the use of vaccination, in many communities in the past, owing to lack of funds and of cooperation of dog owners and others, these measures have not been carried out as vigorously as they should have been, and the disease under these conditions has been brought under control only after considerable time. In recent years, in order to improve their methods of control, many authorities have enlisted prophylactic vaccination as an adjunct.
Since its introduction in the United States, the prophylactic vaccination of dogs has had extensive use. The vaccines prepared in this country are killed vaccines, the killing agent being either phenol or chloroform. Considerable experimental work has been done with these vaccines, both in dogs and more recently in other animals in the laboratory. Although there has at times been some disagreement in results, particularly with laboratory animals, the results of tests on dogs indicate that this method of vaccination has definite value. It should be remembered, however, as noted in the committee report, that the immunity produced by vaccination in dogs is relative and differs in different dogs. Occasional reactions from the vaccine itself have been observed, chiefly paralysis, which has been for the most part transitory but has caused a few deaths. No generally satisfactory explanation as to the cause of these adverse reactions has been advanced. Many thousands, perhaps millions, of dogs have been vaccinated with no untoward effect from the vaccine itself, and there is no doubt that vaccination has in many instances been unjustly accused of causing trouble for which it was in no way responsible. Since there is a possibility of a negative phase following vaccination (a’ period in which an animal might be sensitive to infection preceding the establishment of immunity), it is desirable to confine treated dogs in such a manner as to avoid the possibility of exposure for 2 to 3 weeks.
Much experimental work on rabies has been done in recent years, and laboratory methods for the evaluation of rabies vaccinationbeen made available. By their use it is now possible to produce more uniformly potent rabies vaccines than were available in the past. On the basis of the recent experimental work, the Bureau of Animal Industry now requires that all rabies vaccines prepared by licensed establishments must pass the standards of a test devised.
Rabies does not exist or is of little importance in some States, whereas in many others it is prevalent. In many parts of the country where the disease prevails, misunderstanding concerning its nature and the efforts made to control it has resulted in dissension which has hampered control measures. Probably, however, one of the most important reasons forth prevalence of rabies in many sections is the lack of funds to carry out the control measures properly.
It is. Time for the public at large to realize that rabies should be brought under control, with the goal of eventual eradication from the country, and to lend whole-hearted support to control efforts in each community. Once the disease has been eradicated from this country, its reappearance could be prevented by a 6-monthsquarantine of all dogs imported into the United States from countries where rabies is prevalent.