ABSTRACT
A simple but specific, sensitive and reproducible latex agglutination inhibition assay for the determination of foetal calf sera in viral vaccines has been developed and standardized. The detection limit was at nanogram level. The assay procedure requires two pipetting steps, a short centrifugation stage and the use of a spectrophotometer.
Subject(s)
Blood , Latex Fixation Tests/methods , Viral Vaccines/analysis , Animals , Cattle , Drug Contamination/prevention & control , Horses , Humans , Rabbits , Reproducibility of Results , Sensitivity and Specificity , Species SpecificityABSTRACT
Leningrad-L3 Mumps Vaccine virus has been further attenuated by adaptation and passage on SPF chick embryo fibroblast cell cultures. This new mumps strain has been designated L-Zagreb and has been used to prepare mumps vaccines which meet the WHO requirements. Observations during both the field trial period prior to registration and during the later use of the vaccine showed that the few reactions observed were mild and that seroconversion was obtained in 88-98% of vaccines. The morbidity of mumps in Croatia declined more than tenfold after the introduction of the new vaccine. During a mumps epidemic, vaccine efficiency was calculated to be 97-100%.
Subject(s)
Mumps Vaccine/isolation & purification , Animals , Antibodies, Viral/biosynthesis , Cells, Cultured , Chick Embryo , Child, Preschool , Clinical Trials as Topic , Drug Combinations/therapeutic use , Fibroblasts , Humans , Measles Vaccine/therapeutic use , Measles-Mumps-Rubella Vaccine , Mumps/prevention & control , Mumps Vaccine/standards , Mumps Vaccine/therapeutic use , Rubella Vaccine/therapeutic use , Vaccines, Attenuated/adverse effects , Vaccines, Attenuated/isolation & purification , Vaccines, Attenuated/standards , World Health OrganizationABSTRACT
The live Edmonston-Zagreb measles vaccine is currently produced either on chick-embryo fibroblasts (CEF) or on human diploid cells (HDC). Its stability meets the WHO requirements. Since the vaccine licensure in 1967 the Edmonston-Zagreb measles virus strain has been administered to over 20 million vaccinees either as a monovalent vaccine or as a component of the combined MR, MMR and MM vaccines. Immunogenicity studies have shown the persistence of the elicited HI antibody for a minimum of 16 years. In children aged 13-17 months a greater than 95% seroconversion was recorded after subcutaneous administration both CEF and HDC vaccines. The vaccine has also been shown to be highly immunogenic when administered intranasally. In 6-12 month old infants the Edmonston-Zagreb monovalent vaccine elicited a 100% HI antibody response after both s.c. and i.n. administration. The GMT of antibody 42 days after vaccination was significantly higher in those given HDC vaccine, regardless of the age of the vaccinees or the route of immunization.
Subject(s)
Antibodies, Viral/biosynthesis , Measles Vaccine/immunology , Measles virus/immunology , Mumps Vaccine/immunology , Rubella Vaccine/immunology , Administration, Intranasal , Adolescent , Animals , Cell Line , Chick Embryo , Drug Combinations/administration & dosage , Drug Combinations/immunology , Fibroblasts , Hemagglutination Inhibition Tests , Humans , Infant , Injections, Subcutaneous , Measles Vaccine/administration & dosage , Measles-Mumps-Rubella Vaccine , Mumps Vaccine/administration & dosage , Rubella Vaccine/administration & dosage , Vaccination , Vaccines, Attenuated/administration & dosage , Vaccines, Attenuated/immunologyABSTRACT
The titers of preparations of human leukocyte and human fibroblast interferon were examined to determine their antiviral and anti-invasive activity. The examinations showed a very high correlation of these activities in human fibroblast interferon (r = 0.99), whereas the correlation for human leukocyte interferon was lower. These two interferons have also been found to differ in the relation between antiviral and anti-invasive titers. This difference is highly significant (p less than 0.001).
Subject(s)
Interferons/pharmacology , Viruses/drug effects , HumansABSTRACT
The NIB-3 strain (a recombinant of influenza A/New Jersey/76 and X-31 strains) was further attenuated by nine egg passages at 28 degrees C for the purpose of obtaining a "cold-adapted variant" suitable for preparation of live freeze-dried vaccine with 5% peptone. The vaccine with two infectivity titres, of 7 and 6 log EID50/dose respectively, administered intranasally, was studied in a double-blind placebo-controlled field trial. The reactogenicity of the vaccine was evaluated on the basis of fever reactions during the first three days after vaccination and by the detection of local virus recovery from throat swabs taken on the first four days after vaccination. The majority of vaccines had no fever. On the first day following vaccination the proportions of persons with low-grade fever (up to 37.4 degrees C) were the same in the groups given placebo and vaccine with 6 log EID50/dose respectively. In the group vaccinated with 7 log EID50/dose there were 8% more persons with low-grade fever than in the group given placebo, but this difference was not significant (P greater than 0.05). On the second and the third day after vaccination there was no difference between the proportions of persons with low-grade fever in all the three groups. The highest number of virus isolations, i.e. 26%, was found in persons vaccinated with 7 log EID50/dose, 72 h after vaccination. In the placebo group the virus was not isolated from any person during the entire course of the study.
