[Results of studying a live mumps vaccine from strain L-3 manufactured by the Moscow Research Institute of Viral Preparations. The epidemiological effectiveness of the vaccine]. / Rezul'taty izucheniia zhivoi parotitnoi vaktsiny iz shtamma L-3 proizvodstva Moskovskogo nauchno-issledovatel'skogo instituta virusnykh preparatov. Epidemiologicheskaia éffektivnost' vaktsiny.

A controlled experiment was carried out to study the epidemiological effectiveness of live mumps vaccine from the L-3 strain, the importance of urgent prophylaxis by vaccination in mumps foci and to evaluate the economic effectiveness of mass prophylaxis of mumps by vaccination. The observations involved 113,967 children of 1 to 12 years. Vaccinations were given to 51,701 subjects and 62,256 subjects were the control group. The groups were formed by random selection. One vaccination dose contained 10(4)HAdU50 of mumps virus. The results attest to high epidemilogical effectiveness of the mumps vaccine. The incidence of mumps among the vaccinees was 29.7-fold lower than among unvaccinated, and the coefficient of protection was 96.6%. The urgent vaccination vaccination prophylaxis carried out in children's institutions during the period of introduction of mumps arrested the outbreak within one month, nad the duration of quarantine was reduced 2-3-fold. As a result of the vaccination the economic effect of 290,000 roubles was achieved.

[Results of studying a live mumps vaccine from strain L-3 manufactured by the Moscow Research Institute of Viral Preparations. The reactogenic and antigenic properties of the vaccine]. / Rezul'taty izucheniia zhivoi parotitnoi vaktsiny iz shtamma L-3 proizvodstva Moskovskogo nauchno-issledovatel'skogo instituta virusnykh preparatov. Reaktogennye i antigennye svoistva vaktsiny.

The reactogenic and antigenic properties of live mumps vaccine from the L-3 strain were studied in 1507 children of 1 to 12 years of age. A single injection was given, one immunizing dose containing 10(4)HAdU50 of mumps virus. The live mumps vaccine from the L-3 strain irrespective of the lot of preparation, kind (live or lyophilized), method of application (jet-injector or needle/syringe), age of the vaccinees and the amount of virus in the immunizing dose received by a vaccinee, was demonstrated to be practically areactogenic and markedly antigenic. Serological examinations by neutralization tests of 346 paired serum specimens established variation in seroconversion between individual lots to be within 62.5--82.3% (average 69.9%) of cases. Comparative studies on the postvaccination and postinfection immunitiy in mumps showed the level of antibody in the vaccinees to vary within 4.2--5.1 log2 in different years, and in convalescents within 5.1--5.9 log2 in the same years. The results indicate a sufficiently high and intensive immunity for 5 years (the observation period).