Molecular epidemiological investigation to determine the source of a fatal case of serotype 22F pneumococcal meningitis.

A child's death due to pneumococcal meningitis after contracting the disease in an after-school programme prompted an investigation to assess nasopharyngeal (NP) carriage among her contacts. The serotype of the meningitis case isolate was determined, together with the serotypes of the NP specimens of contacts, comprising the case patient's brother, the case patient's after-school programme contacts and the brother's day-care centre (DCC) contacts. NP swabs from 155 children and 69 adults were obtained. Real-time PCR and conventional multiplex PCR (CM-PCR) assays were used to detect pneumococcal carriage and determine serotypes. Broth-enriched culture of NP specimens followed by pneumococcal isolation and Quellung-based serotyping were also performed. DNA extracts prepared from cerebrospinal fluid of the index case and from the NP strain isolated from the brother and from one attendee of the brother's DCC were subjected to genotyping. Pneumococcal carriage assessed by real-time PCR and culture was 49.6 and 36.6%, respectively (P<0.05). Twenty-three serotypes were detected using CM-PCR, with serotypes 6A/6B, 14, 19F, 6C/6D, 22F/22A, 23F and 11A/11D being the most frequent. All eight serotype 22F/22A NP specimens recovered were from children attending the brother's DCC. The meningitis case isolate and the NP carriage isolate from the patient's brother were both serotype 22F and shared the same new multilocus sequence type (ST6403) with the attendee of the brother's DCC. CM-PCR proved to be useful for assessing carriage serotype distribution in a setting of high-risk pneumococcal transmission. The causal serotype appeared to be linked to the brother of the case patient and attendees of his DCC.

Pneumonia and poverty: a prospective population-based study among children in Brazil.

BACKGROUND: Children in developing country suffer the highest burden of pneumonia. However, few studies have evaluated associations between poverty and pneumonia. METHODS: A prospective population-based study on pneumonia was carried out as part of the Latin America Epidemiological Assessment of Pneumococcus (LEAP study). Chest x-rays were obtained for children one to 35 months old with suspected pneumonia presenting to emergency care centers and hospital emergency rooms in Goiania, Brazil. Chest radiographs were evaluated according to WHO guidelines. Clustering of radiologically-confirmed pneumonia were evaluated using a Poisson-based spatial scan statistic. Associations between census socioeconomic indicators and pneumonia incidence rates were analyzed using generalized linear models. RESULTS: From May, 2007 to May, 2009, chest radiographs were obtained from 11 521 children with clinical pneumonia; 3955 episodes were classified as radiologically-confirmed. Incidence rates were significantly higher in very low income areas (4825.2 per 105) compared to high income areas (1637.3 per 105). Spatial analysis identified clustering of confirmed pneumonia in Western (RR 1.78; p=0.001) and Southeast (RR 1.46; p=0.001) regions of the city, and clustering of hospitalized pneumonia in the Western region (RR 1.69; p=0.001). Lower income households and illiteracy were associated with pneumonia incidence. CONCLUSIONS: In infants the risk of developing pneumonia is inversely associated with the head of household income and with the woman educational level. Areas with deprived socioeconomic conditions had higher incidence of pneumonia and should be targeted for high vaccination coverage.

Carriage of Haemophilus influenzae among Brazilian children attending day care centers in the era of widespread Hib vaccination.

Haemophilus influenzae type b vaccine was introduced into the Immunization Program of Brazil in 1999 and no study has evaluated the impact of Hib vaccination in H. influenzae carriage so far. In June 2010, Brazil introduced the 10-valent pneumococcal nontypeable H. influenzae (NTHi) conjugate vaccine (PHiD-CV). We investigated the prevalence of encapsulated H. influenzae and NTHi isolates in nasopharyngeal samples of 1192 children attending day-care centers in Goiânia, central Brazil. H. influenzae carriage rate was 32.1% and 38.4% of them carried ß-lactamase TEM-1 gene. Serotype f (4.6%) was the most frequent encapsulated isolate, type b was recovered in only 0.7% and carriage rate of NTHi was 23.3%. Recurrent acute otitis media and NTHi were independently associated with colonization by ß-lactamase producing H. influenzae. Changes in frequency of H. influenzae carriage isolates should be carefully monitored to assess the impact of the PHiD-CV on NTHi carriage in young children.