Serogroup-specific epidemiology of Streptococcus pneumoniae: associations with age, sex, and geography in 7,000 episodes of invasive disease.

A study sample of 7,010 episodes of invasive Streptococcus pneumoniae disease was obtained by combining 13 existing datasets. Disease episodes due to each of 12 pneumococcal serogroups (1, 3-9, 14, 18, 19, and 23) were then compared with episodes in a constant internal control group to describe serogroup-specific variations in disease frequency by age, sex, and geographic origin. The results are presented as odds ratios (with 95% confidence intervals) derived by logistic regression, with adjustment for the major confounders, including dataset of origin. Variation in the male:female ratios between serogroups is small, suggesting that capsular characteristics are an unlikely explanation for the male preference of S. pneumoniae. Serogroups associated with higher nasopharyngeal prevalence (e.g., 19 and 24) are relatively more common in Europe and North American, while the invasive serotypes 1 and 5 are much more common in South America. The custom of reporting serogroup frequencies in two age groups, children and adults, conceals much of the variation in the age distributions across the whole span of life. The reduction of risk associated with serogroups 6, 14, 18, 19, and 23 beyond childhood follows different gradients, being most abrupt in serogroups 14 and most gradual in serogroup 18. The relative risk of disease with serotype 1 declines steadily throughout life, while with serotypes 3 and 8 it increases over middle age. Serogroups 7 and 23 are found unusually frequently in the third decade of life. Because of the wide differences in the epidemiology of individual serogroups of S. pneumoniae, it is questionable whether pneumococcal infection should continue to be classified as a single disease entity.

The role of Public Health Laboratory in the problem of salmonellosis in Sao Paulo, Brazil

No periodo de 1950-90 foram identificadas 45.862 cepas de Salmonella, sendo 31.517 provenientes de infeccoes humanas e 14.345 de materiais de origem nao humana. O objetivo deste trabalho foi analisar as alteracoes ocorridas quanto a frequencia dos sorotipos isolados neste periodo. No periodo 1950-66, nao houve predominio evidente de nenhum sorotipo; entretanto, no perido 1970-76, com inicio em 1968, a S. Typhimurium passou a ser o sorotipo predominante, representando 77,7 por cento dos sorotipos isolados. Observou-se um aumento significativo da S. Agona, bem como de uma grande variedade de sorotipos. Quanto as salmonelas de origem nao humana, chama a atencao o grande numero (mais de 100) de sorotipos...

The role of public health laboratory in the problem of salmonellosis in São Paulo, Brazil.

From 1950 to 1990 a total of 45,862 strains (31,517 isolates from human sources, and 14,345 of non-human origin) were identified at Instituto Adolfo Lutz. No prevalence of any serovars was seen during the period 1950-66 among human sources isolates. Important changing pattern was seen in 1968, when S. Typhimurium surprisingly increased becoming the prevalent serovar in the following decades. During the period of 1970-76, S. Typhimurium represented 77.7% of all serovar of human origin. Significant rise in S. Agona isolation as well as in the number of different serovars among human sources strains were seen in the late 70' and the 80's. More than one hundred different serovars were identified among non-human origin strains. Among serovars isolated from human sources, 74.9%, 15.5%, and 3.7% were recovered from stool, blood, and cerebrospinal fluid cultures, respectively. The outbreak of meningitis by S. Grumpensis in the 60's, emphasizes the concept that any Salmonella serovars can be a cause of epidemics, mainly of the nosocomial origin. This evaluation covering a long period shows the important role of the Public Health Laboratory in the surveillance of salmonellosis, one of the most frequent zoonosis in the world.

Distribution of serotypes of Streptococcus pneumoniae isolated from invasive infections over a 16-year period in the greater São Paulo area, Brazil.

Capsular types of pneumococci from normally sterile body sites of 1,622 patients in Brazil were analyzed. Of 1,477 isolates from cerebrospinal fluid, 76.1% were of types represented in the currently available pneumococcal vaccine. The importance of age, time, and place in determining the optimal formulation of pneumococcal vaccine is considered.

[Epidemiologic markers of Salmonella typhimurium and Salmonella agona]. / Marcadores epidemiológicos de Salmonella typhimurium e Salmonella agona.

Among S. typhimurium and S. agona strains isolated during the period from 1971 to 1987, the biotypes, colicine types and resistance patterns were determined for 734 S. typhimurium and 631 S. agona strains. Among 734 S. typhimurium strains 65 biotypes were disclosed with prevalence of biotypes 1a (28.34%), 1b (29.84%) and 9 bi (18.28). Concerning S. agona, the biotype 1a represented by 87.16%, was the commonest clone among our strains. Although colicine typing added little information to characterize these serotypes, it should be usefull when applied in epidemiological study of outbreaks. It was observed multiply antimicrobial resistance mainly among human strains, particularly from nosocomial origins.

[Serotypes of Streptococcus pneumoniae isolated from cerebrospinal fluid in 1977-1988 in São Paulo City, Brazil]. / Sorotipos de Streptococcus pneumoniae isolados de líquido cefalorraquidiano no período de 1977-1988 na cidade de São Paulo, Brasil.

Since 1977, the Instituto Adolfo Lutz (IAL) is having interest in the serotyping of S. pneumoniae or pneumococcus from infections caused by this bacteria. The isolated strains have been sent to the WHO Pneumococcal Reference Center, Pennsylvania, U.S.A.. From 1977 to 1988, 1.000 pneumococcus strains isolated from cerebrospinal fluid were typed, according to Danish nomenclature, and 60 serotypes were identified. The most frequent serotypes were 1, 6B, 18C, 14, 5, 3, 6A, 23F, 19F, and 38. Among different age groups, they showed a variable incidence, with serotype 6B in the ages of zero to almost 2 years old, serotype 1 in the age group of 2 to 50 years old, and serotype 3 in the ages over 50. During the 12 years study, 25 serotypes showed some uniformity in the frequency, the same as with the seasonal fluctuations. Concerning the severity of the pneumococcal infections, chiefly meningitis, and the few information related to pneumococcus serotypes which occur in the area, it was considered of high relevance to have the information of serotypes, once polysaccharide vaccines have been employed with success to prevent these infections.