Transmission of Streptococcus pneumoniae in an urban slum community.
BACKGROUND
Inhabitants of slum settlements represent a significant proportion of the population at risk for pneumococcal disease in developing countries.


METHODS
We conducted a household survey of pneumococcal carriage among residents of a slum community in the city of Salvador, Brazil.


RESULTS
Among 262 subjects, 95 (36%) were colonized with Streptococcus pneumoniae. Children <5 years of age (OR, 8.0; 95% CI, 3.5-18.6) and those who attended schools (OR, 2.7, 95% CI, 1.2-6.0) had significantly higher risk of being colonized. Of 94 isolates obtained from colonized individuals, 51% had serotypes included in the seven-valent pneumococcal conjugate vaccine. Overall, 10% (9 of 94 isolates) were nonsusceptible to penicillin and 28% (27 of 94 isolates) were resistant to cotrimoxazole. BOX-PCR, PFGE and MLST analyses found that 44% of the carriage isolates belonged to 14 distinct clonal groups. Strains of the same clonal group were isolated from multiple members of 9 out of the 39 study households. Nineteen carriage isolates had genotypes that were the same as those identified among 362 strains obtained from active surveillance for meningitis.


CONCLUSIONS
The study's findings indicate that there is significant intra- and inter-household spread of S. pneumoniae in the slum community setting. However, a limited number of clones encountered during carriage among slum residents were found to cause invasive disease.
Reis
Joice Neves
JN
Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz/MS, Rua Waldemar Falcão 121, Ministério da Saúde, Salvador, Bahia 40296-710, Candeal, Brazil. joice@bahia.fiocruz.br
Palma
Tania
T
Ribeiro
Guilherme S
GS
Pinheiro
Ricardo M
RM
Ribeiro
Cassio Tâmara
CT
Cordeiro
Soraia Machado
SM
da Silva Filho
H P
HP
Moschioni
Monica
M
Thompson
Terry A
TA
Spratt
Brian
B
Riley
Lee W
LW
Barocchi
Michele A
MA
Reis
Mitermayer G
MG
Ko
Albert I
AI
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D015373:Bacterial Typing Techniques; D001938:Brazil / Q000453:epidemiology; D002353:Carrier State / Q000453:epidemiology* / Q000382:microbiology / Q000635:transmission*; D002648:Child; D002675:Child, Preschool; D016000:Cluster Analysis; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000235:genetics; D024881:Drug Resistance, Bacterial; D005260:Female; D005838:Genotype; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D006801:Humans; D007223:Infant; D008297:Male; D022401:Meningococcal Vaccines / Q000276:immunology; D008826:Microbial Sensitivity Tests; D022242:Pneumococcal Vaccines / Q000276:immunology; D011204:Poverty Areas; D012307:Risk Factors; D012574:Schools; D012703:Serotyping; D013296:Streptococcus pneumoniae / Q000145:classification* / Q000302:isolation & purification*
D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D000069443:Heptavalent Pneumococcal Conjugate Vaccine; D022401:Meningococcal Vaccines; D022242:Pneumococcal Vaccines