ABSTRACT
The long-term impact of Haemophilus influenzae type b (Hib) conjugate vaccine, introduced throughout Latin America in the late 1990s, has not been evaluated. Active surveillance for H. influenzae meningitis was performed from August 9, 1996 to August 8, 2004 in Metropolitan Salvador, Brazil. Five years after the introduction of Hib conjugate vaccine, Hib meningitis incidence decreased from 2.39 to 0.06 cases per 100,000 population (98%) overall, and from 60.9 to 3.1 cases per 100,000 population (95%) in children <1 year of age. A transient serotype replacement phenomenon was observed associated with a small increase of meningitis due to two H. influenzae type a clonal groups. These findings indicate that Hib immunization campaign has led to the virtual elimination of Hib disease in this region.
Subject(s)
Haemophilus Vaccines , Haemophilus influenzae type b/immunology , Immunization Programs , Meningitis, Haemophilus/epidemiology , Population Surveillance , Tetanus Toxoid , Vaccines, Conjugate , Brazil/epidemiology , Child , Child, Preschool , Haemophilus Vaccines/administration & dosage , Haemophilus Vaccines/immunology , Haemophilus influenzae type b/classification , Haemophilus influenzae type b/isolation & purification , Humans , Incidence , Infant , Infant, Newborn , Meningitis, Haemophilus/microbiology , Meningitis, Haemophilus/mortality , Meningitis, Haemophilus/prevention & control , Program Evaluation , Serotyping , Tetanus Toxoid/administration & dosage , Tetanus Toxoid/immunology , Vaccines, Conjugate/administration & dosage , Vaccines, Conjugate/immunologyABSTRACT
The purposes of this investigation were to identify the frequency and risk factors of leptospiral infection among children aged between 2 and 15 years in Salvador, Bahia, household contacts of patients (index-cases) hospitalized at Couto Maia Hospital due to Leptospira interrogans (ELISA IgM positive). Among 148 household contacts from 25 selected index-cases, clinical and epidemiological data were collected and ELISA IGM and IgG were performed in paired sera (between 20 days) from 73 (49.3%). This diagnostic method divided the 73 household contacts into three groups: group A (acute or recent leptospiral infection), 30 (41.1%) children, group B (not- infected ) 34 (46.6%) and group C, (past infection) nine (12.3%) children. In group A five (16.7%) had cold syndrome simile. No statistically significant difference was found between groups A and B for sex, race, age and presence of pet dog. However, in group A there was a statistically significant predominance (p < 0.05%) of: contact with natural water courses; index-case sibling aged under fifteen years; female sex and over 9 years old; and principally lack of appropiate trash disposal in the residential area. In conclusion, leptospiral infection in children (from 2 to 15 years of age) in Salvador is underestimated, because it is asymptomatic or presents as a cold syndrome simile.
Subject(s)
Leptospirosis/epidemiology , Adolescent , Age Factors , Animals , Antibodies, Bacterial/blood , Brazil/epidemiology , Child , Child, Preschool , Cross-Sectional Studies , Dogs , Enzyme-Linked Immunosorbent Assay , Female , Humans , Immunoglobulin M/blood , Leptospira interrogans/immunology , Leptospirosis/blood , Leptospirosis/diagnosis , Male , Risk Factors , Sex FactorsABSTRACT
Os objetivos deste trabalho foram estimar a freqüência da leptospirose e os fatores de risco em crianças de 2 a 15 anos de idade, de ambos sexos, contactantes-domiciliares dos pacientes internados (casos-índices) no Hospital Couto Maia, com diagnóstico de leptospirose (ELISA-IgM positivo). De 148 pessoas, dos domicílios dos 25 casos-índices, selecionados aleatoriamente, 73 (49,3 por cento) contatos-domiciliares foram submetidos à avaliaçäo clínico-epidemiológica e ao mesmo teste diagnóstico em soros pareados. Os resultados das IgM e IgG classificaram os 73 contatos-domiciliares em três grupos: A (infecçäo aguda ou recente), 30 (41,1 por cento) casos; B (näo-infectados), 34(46,6 por cento) crianças e C (infecçäo antiga), nove (12,3 por cento). Entre os do Grupo A, cinco (16,7 por cento) apresentaram manifestaçöes de resfriado comum. O sexo, o grupo racial, a idade e a presença de cäo no domicílio näo apresentaram diferenças estatísticas significantes, entre os grupos A e B. Todavia, nas crianças do grupo A predominaram (p<0,05): contato com água na natureza; irmäo caso-índice e menor de 15 anos; sexo feminino e maior de 9 anos de idade e, principalmente, a falta de coleta do lixo nos locais de residência. Em conclusäo, a leptospirose em crianças de Salvador é subestimada, porque é oligossintomática ou similar ao resfriado comum
Subject(s)
Adolescent , Animals , Child , Child, Preschool , Dogs , Female , Humans , Male , Leptospirosis/epidemiology , Age Factors , Antibodies, Bacterial/blood , Brazil/epidemiology , Cross-Sectional Studies , Enzyme-Linked Immunosorbent Assay , Immunoglobulin M/blood , Leptospira interrogans/immunology , Leptospirosis/blood , Leptospirosis/diagnosis , Risk Factors , Sex FactorsABSTRACT
Surveillance for Haemophilus influenzae meningitis cases was performed in Salvador, Brazil, before and after introduction of H. influenzae type b (Hib) immunization. The incidence of Hib meningitis decreased 69% during the 1-year period after initiation of Hib immunization (from 2.62 to 0.81 cases/100,000 person-years; P<.001). In contrast, the incidence for H. influenzae type a meningitis increased 8-fold (from 0.02 to 0.16 cases/100,000 person-years; P=.008). Pulsed-field gel electrophoretic analysis demonstrated that H. influenzae type a isolates belonged to 2 clonally related groups, both of which were found before Hib immunization commenced. Therefore, Hib immunization contributed to an increased risk for H. influenzae type a meningitis through selection of circulating H. influenzae type a clones. The risk attributable to serotype replacement is small in comparison to the large reduction in Hib meningitis due to immunization. However, these findings highlight the need to maintain surveillance as the use of conjugate vaccines expands worldwide.
Subject(s)
Haemophilus Vaccines/immunology , Haemophilus influenzae type b/classification , Haemophilus influenzae/classification , Meningitis, Haemophilus/prevention & control , Polysaccharides, Bacterial/immunology , Bacterial Capsules , Brazil , Child , Child, Preschool , Female , Haemophilus influenzae/pathogenicity , Humans , Immunization , Infant , Male , Meningitis, Haemophilus/microbiology , Serotyping , VirulenceABSTRACT
For the purpose of identifying the frequency that enterovirus, leptospires, arbovirus cause aseptic meningitis syndrome (AMS) during non-epidemic periods and comparing patients with and without laboratory evidence for an etiologic agent, 112 patients were selected aged between 3 months and 15 years and a clinical suspicion of AMS and were referred to Couto Maia Hospital, the Infectious and Parasitic Disease Reference Center for Salvador, Bahia. In 44.6% (n=50), the etiologic agent for the diagnosis was laboratory-confirmed: enterovirus was identified in 37.7% (n=42) of the cases by the PCR Amplicor diagnostic kit, cerebrospinal fluid or fecal culture isolation; Leptospira sp. in 7.12% (n=8) by the microagglutination test; and arbovirus in non of the cases by inhibition of passive hemagglutination. In 14 of the 22 enteroviral isolates that were evaluated, 6 different serotypes were identified with Echovirus-4 being the major serotype (27.2%; 6/22) among all found (Coxsackie B2, B3, B6 and B9; Enterovirus 71). In conclusion, enteroviruses were the most frequent etiologic agent of AMS and that leptospirosis should be included in the differential diagnosis. In addition, patients with and without laboratory-confirmed identification of the etiologic agent had similar demographic and clinical characteristics and cerebrospinal fluid findings (p >0.05), therefore suggesting that patients without a confirmed diagnosis had enteroviral or leptospiral etiologies.
Subject(s)
Leptospirosis , Meningitis, Aseptic/microbiology , Adolescent , Brazil , Child , Child, Preschool , Female , Humans , Infant , Male , Meningitis, Aseptic/diagnosisABSTRACT
Objetivando verificar a freqüência de enterovírus (EV), leptospiras e arbovírus como agentes causais da síndrome da meningite asséptica (SMA), em períodos näo-epidêmicos, e comparar os pacientes com e sem diagnóstico etiológico determinado, foram selecionados 112 pacientes de idade entre 3 meses e 15 anos, com suspeita clínica de SMA, referenciados para Hospital Couto Maia, especializado em Doenças Infecciosas e Parasitárias (Salvador, Bahia), Em 44,6 por cento (n=50) a etiologia foi determinada: enterovírus em 37,7 por cento (n=42) dos casos, pelo teste de PCR Amplicor, por cultura do líquor e/ou de fezes; a Leptospira sp. em 7,1 por cento (n=8), pelo método da micro-aglutinaçäo, e nenhum caso de arbovírus foi detectado (inibiçäo da hemaglutinaçäo passiva). Entre os 14 enterovírus dos 22 isolados, foram identificados seis diferentes sorotipos, sendo o Echovirus-4 predominante (27,2 por cento; 6/22) entre outros (Coxsackie B2, B3, B6 e B9; EV 71). Conclui-se que, os enterovírus foram os agentes mais freqüentes, e que a leptospirose deve ser lembrada no diagnóstico diferencial da SMA. Uma vez que as características clínicas e liquóricas dos pacientes dos grupos com e sem determinaçäo do agente etiológico foram semelhantes, pode-se supor que o diagnóstico presuntivo de SMA é de provável etiologia viral ou pela leptospira
