[Thermostability of rabies vaccine, type Fuenzalida & Palacios, for human use]. / Termoestabilidade da vacina contra a raiva, tipo Fuenzalida & Palacios, uso humano.

Ten lots of Fuenzalida & Palacios type antirabies vaccine for human use, produced at the Instituto Butantan (São Paulo, Brazil) were stored at temperatures of 45, 37, 28 and 2-8 degrees C. The potency of each lot was determined in samples taken at varied time intervals using the NIH method and lots presenting antigenic values > or = 0,3 were considered satisfactory for use. After 2 hours at 45 degrees C the antigenic value of one out of 10 lots tested was found to be less than the minimum required value. At 37 degrees C all lots maintained satisfactory antigenic values until the third day of storage, whilst at 28 and 2-8 degrees C the potency was fully maintained, respectively for 10 and 360 days. At the ideal temperature of 2-8 degrees C, 100% of the tested vaccines maintained the minimum required antigenicity for a longer period (16 months) than the expiration time of 6-12 months usually recommended for this type of biological produced in Latin American and Caribbean countries. Thus, the obtained data suggested that in countries still producing Fuenzalida & Palacios type vaccine, the expiration tim could be extended to 16 months, what could prevent the unnecessary discarding of products still in useful condition.

[Photosensitivity and stability of freeze-dried and/or reconstituted measles vaccines (Biken CAM-70 strain)]. / Fotossensibilidade e termoestabilidade de vacinas contra o sarampo (cepa Biken CAM-70) liofilizadas e/ou reconstituídas para administração.

Three different lots of measles vaccines produced with the Biken CAM-70 virus strain were requested from the central cold store of the Public Health Department of the State of S. Paulo, Brazil, and assays on photosensitivity at 2-8 degrees C, and on stability at 28, 36.5 and 45 degrees C were carried out to find out for how long these vaccines would maintain their minimum potency, established as being 3.70 log10 or 5000 TCID50 (50% tissue culture infective dose) per human dose. The analysis of the adjusted straight regression lines indicated that, with the passage of time, the potency of lyophilized or reconstituted vaccines, as well as of vaccines exposed to or protected from light decreased. Light-exposed vaccines, however, became less potent than vaccines protected from the light. None of the vaccine lots studied, reconstituted and stored at 2-8 degrees C, exhibited homogeneity as to sensitivity to light. When freeze-dried vaccines had their photosensitivity studied at 2-8 degrees C, lots 1 and 2 presented greater thermal degradation when exposed to light than when protected from it. However, in both instances, it was found that potency fell below that taken as minimum for the Biken CAM-70 virus strain. At all other temperatures considered, even when protected from light, lots 1 and 2 did not retain the minimum potency. Lot 3 kept the expected stability for 60 days at 2-8 degrees C when protected from light and for 40 days when unprotected, but its thermal degradation at other temperatures was more intense (28 degrees C: 5 days; 36.5 degrees C: 2 days; 45 degrees C: 0.5 day).(ABSTRACT TRUNCATED AT 250 WORDS)

[Biochemical characterization of calf sera used in the maintenance of cell cultures used in virology]. / Caracterização bioquímica de soros de bezerros utilizados na manutenção de culturas celulares usadas em virologia.

Eight lots of the calf sera employed to supplement culture media for the cultivation of animal cells, of widespread use in virology obtained from calves above and below six months of age were rated as good or as poor cell growth promoters according to their growth promoting capacity (GPC). Parameters related to macronutrients contained in these serum lots were then evaluated with the purpose of establishing their biochemical profiles. The results obtained can be considered as normal values for apparently healthy animal donors. Fluctuations found between the data of this investigation and those mentioned in the literature for certain biochemical parameters are probably due to the methodology employed, the breed and age of the animals, or even to regional diet. Student's "t" test was applied for the statistical analysis of the results and demonstrated that, as far as serum fractions were concerned, no significant differences occurred between sera rated as good and poor cell growth promoters, taking tc = 2.45. For calf sera from animals above and below six months of age, two tests relating to alfa and beta fractions were significant (t = 2.68 and 2.61 respectively). It was demonstrated that the evaluation of the biochemical parameters mentioned "per se" neither leads to the identification of calf sera presenting good or poor GPC, nor of sera harvested from calves younger or older than six months.

Sorbitol-gelatin and glutamic acid-lactose solutions for stabilization of reference preparations of measles virus.

The work reported here sought to assess the protection afforded by two stabilizing solutions (sorbitol-gelatin and glutamic acid-lactose) in preserving the potency of freeze-dried Schwarz strain measles virus during storage with a view to the production of reference preparations and working lots of virus suspensions. Stabilized virus suspensions and control suspensions were stored at -70 degrees C or were freeze-dried and stored at -20 degrees C, and their potency was determined over a storage period of 21 months. It was found that the sorbitol-gelatin imparted more satisfactory stability (r = +0.18) to the freeze-dried virus suspensions than did the glutamic acid-lactose. The results also indicate that sorbitol-gelatin, used under the conditions of this study, is an effective stabilizer in the preparation of freeze-dried suspensions of Schwarz strain measles virus employed as reference preparation working lots.

Potency control of live, attenuated vaccines against measles used in children vaccinations in the State of Sao Paulo, Brazil (1976-1980).

Pela inoculacao de diluicoes seriadas da vacina viva, atenuada, contra o sarampo,em culturas de celulas Vero, foram titulados para controle de potencia, 161 lotes de vacinas importadas da Inglaterra, Franca e Belgica, destinadas a vacinacao da populacao infantil do Estado de Sao Paulo. Nas condicoes do teste, 20,0, 11,5 e 25,0% dos lotes de vacina testadas, importadas da Inglaterra, Franca e Belgica respectivamente, nao apresentaram o titulo minimo exigido; dentre os 72 lotes importados da Franca e liofilizados no Brasil, nao ocorreram impugnacoes devidas a insuficiencia de titulo