Hepatitis B surface antigen seroprevalence among pre- and post-vaccine cohorts in Cambodia, 2017

Ork, Vichit; Woodring, Joseph; Hossain, Md. Shafiqul; Wasley, Annemarie; Nagashima, Shintaro; Yamamoto, Chiyo; Chuon, Channarena; Sugiyama, Aya; Ohisa, Masayuki; Akita, Tomoyuki; Ko, Ko; Mao, Bunsoth; Tanaka, Junko

doi:10.1016/j.vaccine.2019.06.073

Cited by 24 publications

(35 citation statements)

References 7 publications

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“…Here by this study, the rate of mother-to-child transmission of HBV infection showed very low percentage (< 1%) which indirectly proves the effectiveness of hepatitis B vaccination to all infant as national immunization program in Burkina Faso. The similar study in Cambodia also showed the effectiveness of hepatitis B vaccination including hepatitis B birth dose vaccine within 24 h after delivery which significantly reduce HBsAg prevalence to less than 1% in post-vaccine cohort of 5-7 years old children [31].…”

Section: Discussionmentioning

confidence: 63%

The changing epidemiology of hepatitis B and C infections in Nanoro, rural Burkina Faso: a random sampling survey

Lingani

Akita

Ouoba³

et al. 2020

BMC Infect Dis

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Background: This study sought to provide up-to-date hepatitis B (HBV) and C (HCV) seroprevalence in rural Burkina Faso decade after hepatitis B vaccine was introduced in the national immunization scheduled for children. Methods: In 2018, a community-based, random sampling strategy with probability proportional to population size was conducted in Nanoro to investigate the prevalence of viral hepatitis in children and their mothers. Sociodemographic, vaccination history and risk factors were assessed by interview and health books. HBsAg rapid tests were done by finger prick and Dried Blood Spots (DBS) were collected for hepatitis seromarkers by chemiluminescence enzyme immunoassay. Positive samples underwent confirmatory PCR and phylogenetic analysis. Results: Data were presented on 240 mother-child pairs. HBsAg Prevalence was 0.8% in children and 6.3% in mothers. Hepatitis B core antibody positivity was 89.2% in mothers, 59.2% in children and was associated with age, sex and scarification. Hepatitis B surface antibodies prevalence was 37.5% in children and 5.8% in mothers. Good vaccination coverage was limited by home delivery. Phylogenetic analysis of HBV strains based on full genome sequences (n = 7) and s-fragment sequences (n = 6) revealed genotype A, E, and recombinant A3/E. Viral genome homology was reported in one mother-child pair. Anti-HCV prevalence was 5.4% in mothers, 2.1% in children and strains belonged to genotype 2. Conclusions: In Nanoro, HBsAg prevalence was low in children, intermediate in mothers and mother-to-child transmission persists. Home delivery was a limiting factor of Hepatitis B vaccination coverage. HBV genotype E was predominant and genotype A3/E is reported for the first time in Burkina Faso.

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Section: Discussionmentioning

confidence: 63%

The changing epidemiology of hepatitis B and C infections in Nanoro, rural Burkina Faso: a random sampling survey

Lingani

Akita

Ouoba³

et al. 2020

BMC Infect Dis

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“…Types of DBS used in this study. HemaSpot samples, all of them were initially screened and confirmed by WHO standard Rapid point of care HBsAg test, were collected using DBS(HemaSpot) and venipuncture from 5-6 years-old children and their mothers from a nationally representative epidemiological survey conducted in Cambodia in 2017and were used to evaluate the rate of agreement and specificity of DBS 28 . DBS samples were shipped at −80 degrees from Cambodia to Japan by the World Courier.…”

Section: Types Of Hbsag Rapid Point Of Care Test Used In This Studymentioning

confidence: 99%

Evaluation of the efficiency of dried blood spot-based measurement of hepatitis B and hepatitis C virus seromarkers

Yamamoto

Nagashima

Isomura

et al. 2020

Sci Rep

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Although hepatitis B (HBV) and C (HCV) virus infections are still global health issues, measuring sero-markers by standard venipuncture is challenging in areas limited with the adequate human resources and basic infrastructure. This study aimed to inform the usefulness of dried blood spot (DBS) sampling technique for epidemiological study of HBV and HCV in the resources limited areas. We compared specimen recovery rate expressed as analytical sensitivity ratio of HBsAg, HBcAb and anti-HCV between serum specimens and DBS samples (HemaSpot vs Whatman903). Sensitivity ratio was calculated as the ratio of the measured value from DBS to the measured value from serum. Then both the qualitative and quantitative comparisons of HBsAg detection by DBS were done using Cambodian samples. HBsAg, HBcAb and anti-HCV sensitivity ratios for the highest sample dilution (8fold) were 31.2:1, 38.9:1 and 32.0:1 for Whatman903 card and 17.6:1, 23.5:1 and 26.3:1 for HemaSpot respectively. Detection efficacy of HemaSpot (80%) was not inferior to Whatman903 (60%) after 1 month storage, and no significant difference in any hepatitis virus sero-markers was observed in HemaSpot-spotted patient samples stored for 2 weeks at −25 °C and 29 °C. All reference HemaSpot-spotted 400 HBsAg sero-negative samples showed negative. Sensitivity and specificity of HBsAg in HemaSpot were 92.3% and 100%. The recovery expressed as analytical sensitivity ratio of HBsAg, HBcAb and anti-HCV of HemaSpot specimen were not inferior to Whatman903. Therefore, DBS with its usefulness proved as an acceptable tool for large epidemiological study of HBV and HCV in resources limited remote area. Hepatitis B virus (HBV) and hepatitis C virus (HCV) constitute a global health issue. Although there are the effective hepatitis B vaccine since 1982 1 and anti-viral drugs such as interferon alpha, lamivudine and others (tenofovir, adefovir, etc) 2,3 , WHO reported that approximately 257 million people have been infected with HBV and only 16.7% of the people diagnosed with hepatitis B were on anti-viral treatment as of 2016 4. Similarly, even there is no vaccine for HCV till now, the direct-acting antiviral drugs (DAAs) for the treatment of HCV were initially developed in 2011 5 and have since yielded high sustained virologic responses (SVRs) 6. But, WHO reported that 71 million people have been chronically infected with HCV and approximately 19% of global population (13.1 millions) knew their diagnosis and around 5 million only had treated with DAA at the end of 2017 7. Therefore, the World Health Organization (WHO) announced in 2016 a target to eliminate HBV as public health threats by 2030 by reducing the hepatitis B surface antigen (HBsAg) prevalence among children to ≤0.1% 8 and to eliminate HCV by 90% reduction in new diagnosis and 65% reduction in HCV related mortality by 2030 9. However, both

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“…Among 95 HBsAg positive mothers, nine of their children were positive for HBsAg giving MTCT rate of 9.5% (9/95). The detail of background demography were already discussed by Vichit et al [8]. In this study, we present the outcomes from genome sequences analysis.…”

Section: Study Participantsmentioning

confidence: 80%

“…This was the nationwide sero-epidemiological study on HBsAg prevalence among 5-7 years old children and their mothers from 25 provinces of the whole Cambodia in 2017 using the multistage stratified random sampling strategy. Its study designs was introduced previously [8] and results of HBV prevalence from this study had been accepted by WHO Western Pacific Regional Office. Dried blood spot (DBS) using HemaSpot™ (Spot on Science Inc., Austin, USA) samples were collected from 2520 children and their 2028 mothers but two children DBS samples and five mothers' DBS samples were excluded for their insufficient amount of blood for measurement.…”

Section: Subjects Of the Studymentioning

confidence: 99%

“…After introduction of HepB vaccine in the whole Cambodia, HBsAg prevalence among ≤5 years old children markedly reduced to 3.5% in 2006 [7] and then dropped to 0.33-3.45% in three provinces of Cambodia in 2011 [5]. Recent nationwide study on HBsAg prevalence among motherchild pairs in 2017 revealed the positive rate of 0.56% among children and 4.39% among their mothers [8]. Very low HBsAg positive rate in children with its reciprocal high positive rate in mothers indicates the needs for further study on HBV in Cambodia.…”

Section: Introductionmentioning

confidence: 99%

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Existence of hepatitis B virus surface protein mutations and other variants: demand for hepatitis B infection control in Cambodia

Takahashi

Nagashima

et al. 2020

BMC Infect Dis

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Background: This study aimed to detect Hepatitis B virus (HBV) genome sequences and their variants as of nationwide scale using dried blood spot (DBS) samples and to provide up-to-date reference data for infection control and surveillance in Cambodia. Method: Among 2518 children age 5-7 years and their 2023 mothers participated in 2017 Cambodia nationwide sero-survey on hepatitis B surface antigen (HBsAg) prevalence using multistage random sampling strategy, 95 mothers and 13 children positive to HBsAg were included in this study. HBV DNA was extracted from DBS, then performed polymerase chain reaction. HBV genotypes and potential variants were examined by partial and full length genomic analysis. Results: HBsAg positive rate was 4.7% (95/2023) in mothers and 0.52% (13/2518) in their children. Genotype C (80.49%) was abundantly found throughout the whole Cambodia whilst genotype B (19.51%) was exclusively found in regions bordering Vietnam. S gene mutants of HBV were found in 24.29% of mothers and 16.67% of children with HBV DNA positive sera. Full-length genome analysis revealed the homology of 99.62-100% in each motherchild pair. Genotype B was clarified to recombinant genotype B4/C2 and B2/C2. Double (48.39%) and combination mutation (32.26%) were observed in core promoter region of HBV C1 strains. Conclusions: This study showed the capable of DBS for large-scale molecular epidemiological study of HBV in resource limited countries. Full-genome sequences yield the better understanding of sub-genotypes, their variants and the degree of homology between strains isolated from mother-child pairs calls for effective strategies on prevention, control and surveillance of mother-to-child HBV transmission in Cambodia.

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Hepatitis B surface antigen seroprevalence among pre- and post-vaccine cohorts in Cambodia, 2017

Cited by 24 publications

References 7 publications

The changing epidemiology of hepatitis B and C infections in Nanoro, rural Burkina Faso: a random sampling survey

The changing epidemiology of hepatitis B and C infections in Nanoro, rural Burkina Faso: a random sampling survey

Evaluation of the efficiency of dried blood spot-based measurement of hepatitis B and hepatitis C virus seromarkers

Existence of hepatitis B virus surface protein mutations and other variants: demand for hepatitis B infection control in Cambodia

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