1. Introduction
Brucellosis is one of the most hazardous infectious diseases
causing considerable economic losses in livestock and posing a
great threat to human health.
Brucellosis is reported not only in all species of agricultural and
domestic animals but in wild animals as well. For example, brucellosis
in bison, deer, elk, and other wild animals is currently a serious
problem for the U.S. (states of Montana, Idaho, and Wyoming, Yellowstone
National Park, and others).
Experience gained over 40 years of combating bovine brucellosis
in the Former Soviet Union (FSU) and the Russian Federation
substantiates the exceptional role of specific prophylaxis in recovery
from this infection. From 1954 to 1970, the use of vaccines
from strain Brucella abortus 19 in the Soviet Union in livestock of
all sex/age groups made it possible to drastically reduce clinical
cases of brucellosis, to eliminate infection foci, and to greatly reduce
the epizootiological and epidemiological disease indicators. At that time, there was intense discussion on the feasibility of using this
vaccine. The main argument against was the prolonged postvaccinal
seropositivity, masking the actual epizootiological status of
the stock and interfering with the recovery of farms. The twofold
immunization with this vaccine of heifers at the age of 3–6 months
and before insemination did not protect them from infection, which
became evident in the considerable increase in the number of
infected sites and ill livestock. This circumstance was the primary
reason for the rejection of immunization of cows with the vaccine
from strain B. abortus 19 in 1970.
The question quickly arose on the need to search for new brucellosis
vaccines with a different approach, which do not cause
prolonged postvaccinal seropositivity in immunized livestock.
Many scientists from veterinary institutions performed studies in
this direction. Several new brucella vaccine strains were proposed,
of which B. abortus 82, obtained at VNIVI (Kazan) by Salmakov [1–7],
proved to be most promising. Testing of the vaccine from this strain
by state boards in laboratory animals and cattle under experimental
and field conditions showed that it had weak agglutinogenic
and pronounced immunogenic properties [7–9]. The vaccine from
strain B. abortus 82 underwent extensive testing in cattle in different
regions of the Russian Federation and republics of the FSU.