scholarly journals HBV seroepidemiology data for Africa provides insights into transmission and prevention

2019 ◽  
Author(s):  
Anna L McNaughton ◽  
José Lourenço ◽  
Phillip Armand Bester ◽  
Jolynne Mokaya ◽  
Sheila F Lumley ◽  
...  

ABSTRACTInternational goals for elimination of hepatitis B virus (HBV) infection set ambitious targets for 2030. In many African populations, HBV prevalence remains high (≥8%) despite the roll-out of infant HBV immunisation from the mid-1990’s onwards. Enhanced efforts are now urgently required to improve an understanding of population epidemiology, in order to determine which interventions are most likely to be effective in advancing populations towards elimination goals. In populations with a high prevalence of infection, catch-up HBV vaccination of adults has sometimes been deployed as a preventive strategy. An alternative approach of ‘test and treat’ could be applied as a tool to interrupt transmission. We used a systematic approach to investigate the relationship between prevalence of HBV infection (HBsAg) and exposure (anti-HBc) in Africa, and then applied a mathematical model to investigate the impact of catch-up vaccination and a ‘test and treat’ strategy in Uganda, representing a high prevalence setting. We demonstrate a strong relationship between the prevalence of HBsAg and anti-HBc (p<0.0001), but with region-specific differences that may reflect different patterns of transmission. In high prevalence settings, catch-up vaccination may have a transient effect but this intervention does not contribute to a sustained decline in prevalence. In contrast, diagnosing and treating infection has a marked impact on reducing prevalence, equivalent to that of infant immunisation. Conclusion: We have developed a high-resolution picture of HBV epidemiology across Africa. Developing insights into regional differences provides an evidence base for the most effective interventions. In combination with robust neonatal immunisation programmes, testing and treating infection is likely to be of most impact in making advances towards elimination targets.

2011 ◽  
Vol 6 (02) ◽  
pp. 148-155 ◽  
Author(s):  
Christabel C Enweronu-Laryea ◽  
Kwamena W.C. Sagoe ◽  
Hope Glover-Addy ◽  
Richard H Asmah ◽  
Julius A Mingle ◽  
...  

Introduction: Vaccination is the most effective preventive strategy against rotavirus disease. Regional differences in prevalent rotavirus genotypes may affect vaccine efficacy. Pre-vaccine surveillance for burden of rotavirus disease, prevalent rotavirus genotypes, and association between rotavirus disease and intussusceptions helps in monitoring the impact of vaccination. Methodology: A prospective study was conducted from January 2008 to December 2009 in children younger than five years hospitalized for longer than 24 hours with acute gastroenteritis. Data on confirmed cases of intussusception were collected retrospectively. Stools were tested by enzyme immunoassay, reverse-transcriptase polymerase chain reaction and nucleotide sequencing.  Results: Acute gastroenteritis (AGE) caused 13.1% (2,147/16,348) of hospitalizations among children under five years. Stools were tested for 50.2% (1077/2147) of AGE cases. Of these, 49% (528/1077) were rotavirus positive. Rotavirus gastroenteritis, non-rotavirus gastroenteritis, and intussusceptions were most prevalent in children under 15 months [80.3%, 74% and 91% respectively]. Rotavirus was detected from more than 60% of acute gastroenteritis cases during peak months. The prevalence of intussusception showed no seasonal pattern. The peak ages of six to twelve months for acute gastroenteritis and five to eight months for intussusception overlapped. G1, G2 and mixed G/P genotypes were common in the isolated rotaviruses. Conclusion: Rotavirus gastroenteritis causes significant morbidity in children younger than five years of age in Ghana. Although the peak age of rotavirus gastroenteritis and intussusceptions overlapped, there was no seasonal correlation between them. The high prevalence of mixed G/P genotypes in Ghanaian children may affect the effectiveness of vaccination.


2001 ◽  
Vol 12 (6) ◽  
pp. 345-350 ◽  
Author(s):  
Jun Zhang ◽  
Shimian Zou ◽  
Antonio Giulivi

OBJECTIVE:To provide a current and comprehensive review of the epidemiology of hepatitis B virus (HBV) in Canada.DATA SOURCES:Published and unpublished epidemiological studies and surveillance reports of the past decade, primarily from Canada were studied. Fifty reports addressing HBV surveillance, incidence and prevalence, transmission-associated risk factors, co-infections, and prevention strategies were reviewed.DATA SYNTHESIS:HBV infection is an important vaccine-preventable infectious disease in Canada. The incidence rate of clinically recognized, acute HBV infection in 1998/1999 was estimated to be 2.3/100,000 people or approximately 700 cases a year. The prevalence of HBV carriers is estimated to be 0.5% to 1.0% of the population, but varies substantially according to population-specific risk factors. Most acute HBV infections are associated with injection drug use or high risk heterosexual activities, but 20% to 30% of acute cases did not report any identified risk factors. Surveillance activities such as the National Notifiable Disease Reporting system provide information regarding trends and risk factors. The primary preventive strategy for HBV consists of universal immunization for preadolescents and/or infants. Other strategies, such as the universal prenatal screening and postnatal immunization, and the prevention of nosocomial acquistion, are also important. The recently described hepatitis B surface antigen (HBsAg) escape mutants may not be detected by current HBsAg test assays, and the existing HBV vaccines may not protect vaccinees from infections by such mutants.CONCLUSION:Ongoing surveillance and research are required to assess risk factors for HBV transmission, evaluate the effectiveness of immunization programs and monitor the impact of HBsAg escape mutants.


2018 ◽  
Vol 23 (6) ◽  
Author(s):  
Alessandro Miglietta ◽  
Chantal Quinten ◽  
Pier Luigi Lopalco ◽  
Erika Duffell

Hepatitis B prevention in European Union/European Economic Area (EU/EEA) countries relies on vaccination programmes. We describe the epidemiology of acute hepatitis B virus (HBV) at country and EU/EEA level during 2006–2014. Using a multi-level mixed-effects Poisson regression model we assessed differences in the acute HBV infection notification rates between groups of countries that started universal HBV vaccination before/in vs after 1995; implemented or not a catch-up strategy; reached a vaccine coverage ≥ 95% vs < 95% and had a hepatitis B surface antigen prevalence ≥ 1% vs < 1%. Joinpoint regression analysis was used to assess trends by groups of countries, and additional Poisson regression models to evaluate the association between three-dose HBV vaccine coverage and acute HBV infection notification rates at country and EU/EEA level. The EU/EEA acute HBV infection notification rate decreased from 1.6 per 100,000 population in 2006 to 0.7 in 2014. No differences (p > 0.05) were found in the acute HBV infection notification rates between groups of countries, while as vaccine coverage increased, such rates decreased (p < 0.01). Countries with universal HBV vaccination before 1995, a catch-up strategy, and a vaccine coverage ≥ 95% had significant decreasing trends (p < 0.01). Ending HBV transmission in Europe by 2030 will require high vaccine coverage delivered through universal programmes, supported, where appropriate, by catch-up vaccination campaigns.


Author(s):  
A. O. Ajayi ◽  
E. E. Emmanuel ◽  
I. O. Oluwayemi ◽  
A. Olu-Taiwo ◽  
M. S. Odimayo

Background: Hepatitis B vaccine has been introduced in Nigeria for over a decade now, yet, data on sero-conversion status of the immunized cohort in the population are scarce. Such data are important for objective evaluation of the impact and effectiveness of the HBV vaccination program. This study therefore aims at determining the sero-conversion status and the prevalence of HBV infection among immunized cohort of children in Ekiti state, Nigeria. Methodology: This cross-sectional study was conducted across the three senatorial districts of Ekiti state, between October and December, 2017. A total of 441 children consisting of 226 males and 215 females (Male to female ratio= 1.1:1). Immunization was confirmed by immunization cards. Multistage sampling technique was used. Questionaire were administered after caregiver’s consent and assent from subjects, 2 to 5 mls of blood samples were then collected and tested for the various hepatitis B viral markers (HBeAg, HBeAb, HBcAb, HBsAb and HBsAg) using Hepatitis B combo kit manufactured by Innovita Biological Technology. Very low levels antibody titres which may not be detectable by qualitative detection method used is a limitation to this study. Results: Subjects were between 5 to 10 years. All subjects had 3 full doses of hepatitis B vaccination before the age of 1 year and all subjects were negative for HBsAg, HBeAg, HBeAB and HBcAb. However, only 47 (10.7%) had detectable HBsAb. Among HBsAb positive patients 22 were males while 25 were females. Our findings showed zero prevalence of hepatitis B but minimal seroconversion rate among vaccinated children in Ekiti state, Nigeria. Conclusion: Hepatitis B vaccination protects children against HBV in the study population. However, seroconversion rate showed that majority of the children may be at risk of HBV infection at a later age. We recommend a booster dose of HBV vaccination.


Author(s):  
Sloane Speakman

In examining the strikingly high prevalence rates of HIV in many parts of Africa, reaching as high as 5% in some areas, how does the discourse promoted by the predominant religions across the continent, Islam and Christianity, affect the outlook of their followers on the epidemic? This question becomes even more intriguing after discovering the dramatic difference in rate of HIV prevalence between Muslims and Christians in Africa, confirmed by studies that have found a negative relationship to exist between HIV prevalence and being Muslim in Africa, even in Sub-Saharan African nations. Why does this gap in prevalence rates exist? Does Islam advocate participating in less risky behavior more so than Christianity? By comparing the social construction, epidemiological understanding and public responses among Muslim populations in Africa with Christian ones, it becomes apparent that many similarities exist between the two regarding discourse and that, rather than religious discourse itself, other social factors, such as circumcision practices, contribute more to the disparity in HIV prevalence than originally thought.


Fifteen to twenty years is how long it takes for the billions of dollars of health-related research to translate into evidence-based policies and programs suitable for public use. Over the past 15 years, an exciting science has emerged that seeks to narrow the gap between the discovery of new knowledge and its application in public health, mental health, and health care settings. Dissemination and implementation (D&I) research seeks to understand how to best apply scientific advances in the real world, by focusing on pushing the evidence-based knowledge base out into routine use. To help propel this crucial field forward, leading D&I scholars and researchers have collaborated to put together this volume to address a number of key issues, including: how to evaluate the evidence base on effective interventions; which strategies will produce the greatest impact; how to design an appropriate study; and how to track a set of essential outcomes. D&I studies must also take into account the barriers to uptake of evidence-based interventions in the communities where people live their lives and the social service agencies, hospitals, and clinics where they receive care. The challenges of moving research to practice and policy are universal, and future progress calls for collaborative partnerships and cross-country research. The fundamental tenet of D&I research—taking what we know about improving health and putting it into practice—must be the highest priority. This book is nothing less than a roadmap that will have broad appeal to researchers and practitioners across many disciplines.


2021 ◽  
pp. 026975802110106
Author(s):  
Raoul Notté ◽  
E.R. Leukfeldt ◽  
Marijke Malsch

This article explores the impact of online crime victimisation. A literature review and 41 interviews – 19 with victims and 22 with experts – were carried out to gain insight into this. The interviews show that most impacts of online offences correspond to the impacts of traditional offline offences. There are also differences with offline crime victimisation. Several forms of impact seem to be specific to victims of online crime: the substantial scale and visibility of victimhood, victimisation that does not stop in time, the interwovenness of online and offline, and victim blaming. Victims suffer from double, triple or even quadruple hits; it is the accumulation of different types of impact, enforced by the limitlessness in time and space, which makes online crime victimisation so extremely invasive. Furthermore, the characteristics of online crime victimisation greatly complicate the fight against and prevention of online crime. Finally, the high prevalence of cybercrime victimisation combined with the severe impact of these crimes seems contradictory with public opinion – and associated moral judgments – on victims. Further research into the dominant public discourse on victimisation and how this affects the functioning of the police and victim support would be valuable.


BMJ Open ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. e047210
Author(s):  
Anurag Bhargava ◽  
Madhavi Bhargava ◽  
Banurekha Velayutham ◽  
Kannan Thiruvengadam ◽  
Basilea Watson ◽  
...  

IntroductionIndia has the largest burden of cases and deaths related to tuberculosis (TB). Undernutrition is the leading risk factor accounting for TB incidence, while severe undernutrition is a common risk factor for mortality in patients with TB in India. The impact of nutritional supplementation on TB incidence is unknown, while few underpowered studies have assessed its impact on TB mortality. We designed an open-label, field-based cluster randomised trial to assess the impact of nutritional supplementation (with food rations) on TB incidence in a group at higher risk of TB infection and disease, viz household contacts (HHC) of patients with microbiologically confirmed pulmonary TB (PTB) in Jharkhand, a state with a high prevalence of undernutrition.Methods and analysisWe shall enrol 2800 adult patients with PTB of the national TB programme, across 28 treatment units in 4 districts, and their approximately 11 200 eligible contacts. The sample size has 80% power to detect the primary outcome of 50% reduction in incidence of active TB in HHC over 2 years of follow-up. Patients and HHC in both the arms will undergo nutritional assessment and counselling. Patients will receive monthly food rations (supplying 1200 kcal and 52 g proteins/day) and multivitamins along with antitubercular treatment. The HHC in the intervention arm will receive food rations (supplying 750 kcal and 23 g proteins/day) and multivitamins while HHC in control arm will be on usual diet. The secondary outcomes in HHC will include effects on nutritional status, non-TB infections. Secondary outcomes in patients are effects on TB mortality, adherence, adverse effects, nutritional and performance status. Substudies will examine micronutrient status and effects on dietary intake, body composition, muscle strength and immune function.Ethics and disseminationThe institutional ethics committee of ICMR-NIRT, Chennai, approved the study (289/NIRT-IEC/2018). The results will be disseminated in publications and presentations.Trial registration numberClinical Trial Registry of India: CTRI/2019/08/020490.


2021 ◽  
Vol 10 (13) ◽  
pp. 2926
Author(s):  
Sirinart Sirilert ◽  
Theera Tongsong

This review aimed to provide an update on the impact of pregnancy on the natural course of hepatitis B virus (HBV) infection and also on the impact of HBV infection on adverse pregnancy outcomes, including mother-to-child transmission (MTCT). For the literature review, original research articles, review articles, and guidelines were narratively reviewed and comprehensively validated. The databases of PubMed, EMBASE, and CINAHL were carefully searched for articles in English on topics related to HBV infection, pregnancy, and vertical transmission from 1960 to May 2021. Immunological changes during pregnancy such as suppression of Th1 response and induction of Th2 immunity lead to an impaired immune reaction to HBV and stimulate viral activity along with the reduction of CD8 T cells to escape immune detection. The impact of pregnancy on the natural course of chronic HBV infection seems to be minimal, while pregnancy can increase morbidity and mortality in the case of advanced HBV hepatitis or cirrhosis. Importantly, hepatitis flare or alanine aminotransferase (ALT) flare can occur during pregnancy and is more common during the postpartum period due to the interaction between HBV and the immune response. Interestingly, the impact of HBV infection on adverse pregnancy outcomes is more serious than ever thought. Updated evidence indicates that pregnancies with chronic HBV infection increase the risk of preterm birth and gestational diabetes, especially in cases of positive hepatitis e antigen (HBeAg).


2020 ◽  
pp. 105566562098275
Author(s):  
Reanna Shah ◽  
Jeffrey R. Marcus ◽  
Dennis O. Frank-Ito

Objectives: To evaluate the magnitude of olfactory recess opacity in patients with unilateral cleft lip nasal deformity (uCLND). Design: Subject-specific 3-dimensional reconstruction of the nasal airway anatomy was created from computed tomography images in 11 (4 males and 7 females) subjects with uCLND and 7 (3 males, and 4 females) normal subjects. The volume and surface area of each subject’s unilateral and bilateral olfactory airspace was quantified to assess the impact of opacification. Qualitatively speaking, patients with 75% to 100% olfactory recess opacification were classified as extreme, 50% to 75% as severe, 25% to 50% as moderate, and 0% to 25% as mild. Results: Of the 11 subjects with uCLND, 5 (45%) were classified as having extreme olfactory recess opacification, 3 (27%) subjects had severe opacification, and 3 (27%) subjects had moderate opacification. Mean (±SD) bilateral olfactory recess volume was significantly greater in normal subjects than in subjects with uCLND (0.9668 cm3 ± 0.4061 cm3 vs 0.3426 cm3 ± 0.1316 cm3; P < .001). Furthermore, unilateral olfactory airspace volumes for the cleft and non-cleft sides in subjects with uCLND were considerably less than unilateral olfactory volume in subjects with normal anatomy (uCLND cleft side = 0.1623 cm3 ± 0.0933 cm3; uCLND non-cleft side = 0.1803 cm3 ± 0.0938 cm3; normal = 0.4834 cm3 ± 0.2328 cm3; P < .001). Conclusions: Our findings indicate a high prevalence of olfactory recess opacification among subjects with uCLND when compared to subjects with normal anatomy. The majority of subjects with uCLND had extreme olfactory recess opacity, which will likely influence their sense of smell.


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