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Introduction and objectives Universal vaccination at birth and in infancy is key to the elimination of chronic hepatitis B infection. We aimed to assess hepatitis B immune-prophylaxis and perinatal transmission knowledge, in a large and ethnically diverse cohort of previously pregnant North American women, chronically infected with hepatitis B. Materials and methods The Hepatitis B Research Network (HBRN) is comprised of 28 Clinical Centers in the United States and Canada. Female cohort participants were administered a questionnaire to assess: (1) their assertion of knowledge regarding HBV prophylaxis at birth, testing, and diagnosis of hepatitis B in their children, and (2) the percentage of affirmative to negative responses for each of the HBV-related interventions her child may have received. The relationship between asserted knowledge, actions taken and maternal demographics were assessed. Results A total of 351 mothers with 627 children born in or after 1992 were included. Median age at enrollment was 39.8 years. Mothers were mostly foreign-born with the largest percentage from Asia (73.4%) and Africa (11.7%). Of the 627 children, 94.5% had mothers who asserted that they knew whether their child had received HBIG or HBV vaccine at birth, for 88.8% of the children, their mothers indicated that they knew if their child was tested for HBV and for 84.5% of children, their mothers knew if the child was diagnosed with HBV infection. Among children whose mothers asserted knowledge of their HBV management, 95.3% were reported to have received HBIG or HBV vaccine, 83.4% of children were said to have been tested for HBV, and 4.8% of children were said to have been diagnosed with HBV. Younger maternal age was the only factor significantly associated with higher percentage of children for whom mothers reported knowledge of testing (p = 0.02) or diagnosis of HBV (p = 0.02). Conclusions While high percentages of North American children had mothers asserting knowledge of HBV prophylaxis and testing, knowledge gaps remain, with mothers of 5.5–15.5% of children lacking knowledge of key components of the HBV prevention and diagnosis in the perinatal setting. Targeted education of HBsAg-positive mothers may aid in closing this gap and reducing vertical transmission.

Sera from 299 fishermen 16 to 80 years old, residents in Cananeia and Iguape counties, southern cost of São Paulo State, Brazil, were studied in order to identify a possible association between the prevalence of specific antibodies to the hepatitis B virus (HBV) and exposure to haematophagus mosquitoes evaluated by the prevalence of arbovirus antibodies. This professional group presented the highest prevalence of arbovirus antibodies (54.1%) in past investigations carried out in this heavily forested region. Detection of antibody to hepatitis B core antigen (anti-HBc) in the sera was done by enzyme immunoassay (Roche). Prevalence of anti-HBc antibodies in this group was 31.4% (94/299) which is very high compared with 7.2% to 15.0% for different groups of healthy adults in State of São Paulo. No significant difference is observed between the prevalences of HBV antibodies in Iguape and Cananeia. Prevalence of anti-HBc and anti-arbovirus antibodies increases with age. There is a concordance in the distribution according to age groups of the frequency of anti-HBc and anti-arbovirus positive sera. Ag HBs was detected in 4% of the studied sera. These results support the hypothesis that the transmission of the hepatitis B virus and the arboviruses may be due to the same factor, one of the possibilities would be by anthropophilic mosquitoes.Soros de 299 pescadores de 18 a 80 anos de idade, residentes nos municípios de Iguape e Cananéia, região sul do Estado de São Paulo, foram estudados com o objetivo de identificar uma possível associação entre a prevalência de anticorpos específicos para a hepatite B e a exposição a mosquitos hematófagos, avaliada indiretamente pela prevalência de anticorpos de arbovírus. Esse grupo profissional apresentou, em pesquisas anteriores nessa área extensamente coberta por mata, a mais alta prevalência de anticorpos de arbovírus (54,1%). Utilizou-se teste imunoenzimático para detecção de anti-HBc e HBs Ag. Em 31,4% dos soros estavam presentes anticorpos anti-HBc, proporção significativamente mais alta que as detectadas em adultos sadios examinados no Estado de São Paulo (7,2% a 15,0%). HBs Ag foi observado em 4% dos soros examinados. As prevalências de anticorpos de arbovírus e hepatite B aumentaram significante-mente com a idade (p < 0,05), ocorrendo concordância na distribuição das freqüências segundo idade entre os soros positivos para hepatite B e para arbovírus. Os resultados sugerem uma forma semelhante de transmissão desses agentes apoiando a hipótese da transmissão de hepatite B por mosquitos antropofílicos.

Sera from 299 fishermen 16 to 80 years old, residents in Cananeia and Iguape counties, southern cost of São Paulo State, Brazil, were studied in order to identify a possible association between the prevalence of specific antibodies to the hepatitis B virus (HBV) and exposure to haematophagus mosquitoes evaluated by the prevalence of arbovirus antibodies. This professional group presented the highest prevalence of arbovirus antibodies (54.1%) in past investigations carried out in this heavily forested region. Detection of antibody to hepatitis B core antigen (anti-HBc) in the sera was done by enzyme immunoassay (Roche). Prevalence of anti-HBc antibodies in this group was 31.4% (94/299) which is very high compared with 7.2% to 15.0% for different groups of healthy adults in State of São Paulo. No significant difference is observed between the prevalences of HBV antibodies in Iguape and Cananeia. Prevalence of anti-HBc and anti-arbovirus antibodies increases with age. There is a concordance in the distribution according to age groups of the frequency of anti-HBc and anti-arbovirus positive sera. Ag HBs was detected in 4% of the studied sera. These results support the hypothesis that the transmission of the hepatitis B virus and the arboviruses may be due to the same factor, one of the possibilities would be by anthropophilic mosquitoes. Soros de 299 pescadores de 18 a 80 anos de idade, residentes nos municípios de Iguape e Cananéia, região sul do Estado de São Paulo, foram estudados com o objetivo de identificar uma possível associação entre a prevalência de anticorpos específicos para a hepatite B e a exposição a mosquitos hematófagos, avaliada indiretamente pela prevalência de anticorpos de arbovírus. Esse grupo profissional apresentou, em pesquisas anteriores nessa área extensamente coberta por mata, a mais alta prevalência de anticorpos de arbovírus (54,1%). Utilizou-se teste imunoenzimático para detecção de anti-HBc e HBs Ag. Em 31,4% dos soros estavam presentes anticorpos anti-HBc, proporção significativamente mais alta que as detectadas em adultos sadios examinados no Estado de São Paulo (7,2% a 15,0%). HBs Ag foi observado em 4% dos soros examinados. As prevalências de anticorpos de arbovírus e hepatite B aumentaram significante-mente com a idade (p < 0,05), ocorrendo concordância na distribuição das freqüências segundo idade entre os soros positivos para hepatite B e para arbovírus. Os resultados sugerem uma forma semelhante de transmissão desses agentes apoiando a hipótese da transmissão de hepatite B por mosquitos antropofílicos.

280 students, between 6 and 14 years old, residents in the Iguape county, southern coast of the State of São Paulo, were studied in order to identify the existence of a possible association between the prevalence of specific antibodies to the hepatitis B virus and the exposure to haematophagous mosquitoes, evaluated indirectly through the prevalence of antibodies to 17 arboviruses isolated in Brazil. The children were from 4 areas with different topographical characteristics: 89 of the children were from the urban zone of the town of Iguape, 89 were from the periurban zone, 30 were from the rural area with extensive banana plantations, and 72 were from the jungle zone. Previous studies had shown significantly higher prevalence of antibodies to different arboviruses in the cultivated zone and the jungle zone, when compared to the urban and periurban zones of Iguape. The detection of antibodies to the HBV surface antigen (HBs Ag) was done through the radioimmunoassay (Ausab, Abbott Laboratory). The cases considered positive were confirmed through the presence of anti-core HBV antibodies (anti-HBc-EIA Roche). A significantly higher prevalence of anti-HBV antibodies was observed in children from the jungle zone (26/72 = 36,1% ) when compared to those from the urban zone (5/89 = 5,6%), peri-urban (6/89 = 6,7%) or from the cultivated zone (0/30 = 0%). The result suggest the existence of a common factor in the dissemination of the arboviruses and the hepatitis B virus, supporting the hypothesis that mosquitoes may play an important role in the HBV transmission in tropical forested region. 280 escolares de 6 a 14 anos de idade, residentes em Iguape, Vale do Ribeira, sudeste do Estado de São Paulo, foram estudados com o objetivo de verificar possível associação entre a prevalência de anticorpos para hepatite B e a exposição a mosquitos hematófagos, avahada indiretamente pela prevalência de anticorpos de arbovirus. As crianças eram originárias de 4 áreas com características topográficas e fitográficas diferentes: 89 residiam em área urbana, 89 em área periurbana, 30 em área de cultivo extensivo de banana e hortaliças e 72 em área florestal. Estudos prévios mostraram significante maior prevalência de anticorpos de arbovirus nas áreas cultivada e florestal do que nas áreas urbana e periurbana. A pesquisa de anti-HBs foi feita por radioimunoensaio (Ausab, Laboratorio Abbott) e de anti-HBc por ensaio imunoenzimático (Roche). Observou-se que os escolares residentes na área florestal apresentaram mais alta prevalência (26/72 = 36.1%) de anticorpos para hepatite B de que os residentes nas áreas urbana (5/89 = 5,6%), periurbana (6/89 = 6.7%) e cultivada (0/30 = 0%). Os resultados sugerem a existência de fator comum na transmissão de arboviruses e de hepatite B, apoiando a hipótese que nas regiões tropicais com presença de mata mosquitos possam desempenhar importante papel na transmissão da hepatite B.

280 students, between 6 and 14 years old, residents in the Iguape county, southern coast of the State of São Paulo, were studied in order to identify the existence of a possible association between the prevalence of specific antibodies to the hepatitis B virus and the exposure to haematophagous mosquitoes, evaluated indirectly through the prevalence of antibodies to 17 arboviruses isolated in Brazil. The children were from 4 areas with different topographical characteristics: 89 of the children were from the urban zone of the town of Iguape, 89 were from the periurban zone, 30 were from the rural area with extensive banana plantations, and 72 were from the jungle zone. Previous studies had shown significantly higher prevalence of antibodies to different arboviruses in the cultivated zone and the jungle zone, when compared to the urban and periurban zones of Iguape. The detection of antibodies to the HBV surface antigen (HBs Ag) was done through the radioimmunoassay (Ausab, Abbott Laboratory). The cases considered positive were confirmed through the presence of anti-core HBV antibodies (anti-HBc-EIA Roche). A significantly higher prevalence of anti-HBV antibodies was observed in children from the jungle zone (26/72 = 36,1% ) when compared to those from the urban zone (5/89 = 5,6%), peri-urban (6/89 = 6,7%) or from the cultivated zone (0/30 = 0%). The result suggest the existence of a common factor in the dissemination of the arboviruses and the hepatitis B virus, supporting the hypothesis that mosquitoes may play an important role in the HBV transmission in tropical forested region. 280 escolares de 6 a 14 anos de idade, residentes em Iguape, Vale do Ribeira, sudeste do Estado de São Paulo, foram estudados com o objetivo de verificar possível associação entre a prevalência de anticorpos para hepatite B e a exposição a mosquitos hematófagos, avahada indiretamente pela prevalência de anticorpos de arbovirus. As crianças eram originárias de 4 áreas com características topográficas e fitográficas diferentes: 89 residiam em área urbana, 89 em área periurbana, 30 em área de cultivo extensivo de banana e hortaliças e 72 em área florestal. Estudos prévios mostraram significante maior prevalência de anticorpos de arbovirus nas áreas cultivada e florestal do que nas áreas urbana e periurbana. A pesquisa de anti-HBs foi feita por radioimunoensaio (Ausab, Laboratorio Abbott) e de anti-HBc por ensaio imunoenzimático (Roche). Observou-se que os escolares residentes na área florestal apresentaram mais alta prevalência (26/72 = 36.1%) de anticorpos para hepatite B de que os residentes nas áreas urbana (5/89 = 5,6%), periurbana (6/89 = 6.7%) e cultivada (0/30 = 0%). Os resultados sugerem a existência de fator comum na transmissão de arboviruses e de hepatite B, apoiando a hipótese que nas regiões tropicais com presença de mata mosquitos possam desempenhar importante papel na transmissão da hepatite B.

Background More than 17 million people in India are chronically infected with the hepatitis B virus (HBV). Approximately one million of the 26 million children born in India annually will develop chronic HBV infection in the course of their lives. Studies have put the HBsAg prevalence rate among pregnant women in India between 0.9 % and 3.1, indicating a considerable need for public health interventions aimed at protecting their offspring from infection. The PAHAL project in Mumbai, India, conducted an HBV knowledge survey among women of childbearing age in three local slum communities preparatory to planning a comprehensive HBV education intervention targeting this population. Methods Female health workers approached all households in three designated slum neighborhoods: one each in the eastern suburbs (ES), western suburbs (WS) and Island City (IC). Female residents aged 18–45 were invited to participate in the study, and those who agreed to participate responded to a questionnaire that was administered in the form of an oral interview. The five sections of the questionnaire addressed demography, hepatitis B knowledge, personal risk related to hepatitis B, pregnancy and childbearing history, and the participant’s most recent pregnancy. A descriptive statistical analysis was performed. Results Health workers submitted 6571 interview forms that were suitable for analysis (ES, 28 %; WS, 34 %; IC, 38 %). Large proportions of study participants were married (89 %), were not employed (94 %) and had completed less than 12 years of school (87 %). Only 240 (3.6 %) women answered yes when asked if they knew about hepatitis B. Among those women, there were high levels of accurate knowledge regarding some modes of hepatitis B transmission but low levels of accurate knowledge regarding other modes. Twenty-two percent of 739 women who had given birth within the previous 36 months reported that they had been tested for HBV during pregnancy. While 70 % of these women reported that their children had received three doses of hepatitis B vaccine, reported vaccination levels varied greatly across the three study areas. Conclusions Despite the availability of a safe HBV vaccine, which is free for newborns and infants in many parts of India, preventing mother-to-child transmission of HBV remains a major challenge. Low awareness of HBV among women of childbearing age in Mumbai-area slums indicates a need for educational interventions targeting this population.