Viral hepatitis is a significant cause of disease and death globally. Yet powerful new medical tools to combat hepatitis C and E still reach only a tiny fraction of people who desperately need them, especially in low-resource and emergency settings.
To mark World Hepatitis Day (July 28th) we highlight recent MSF research on making these breakthrough products more widely accessible and simpler to use.
For hepatitis C, where groundbreaking antiviral drugs can cure nearly all patients, MSF is developing comprehensive, community-based models of care that offer rapid screening, diagnosis, and treatment under one roof. In some settings programs focus on the specific needs of highly vulnerable populations, such as people living in remote areas, forcibly displaced refugees, or those co-infected with HIV or TB or who inject drugs.
Turning to prevention, MSF is exploring ways to use the Hepatitis E vaccine more effectively in areas where poor sanitation and water quality regularly lead to outbreaks. Studies in a South Sudanese camp for internally displaced people are strengthening evidence for the vaccine’s feasibility, efficacy, safety and community acceptance, especially for pregnant women and their fetuses. Another report analyzes strategies for overcoming barriers to widespread vaccine adoption.
BACKGROUND
Hepatitis E was first identified in the 1990s, but major epidemics date back to the 1950s. There is no specific treatment, and it can be fatal especially for pregnant women, causing spontaneous abortion and stillbirths. In 2011, the first vaccine was made available, and in 2015, the WHO recommended its use during epidemics, including for pregnant women. However, several major epidemics occurred without vaccine use. The first mass reactive vaccination took place in 2022 at the Bentiu camp in South Sudan, alongside operational research.
METHODS
We assessed vaccination feasibility and acceptance through coverage surveys and conducted focus group discussions on acceptance. We monitored adverse events following immunization (AEFI) for pharmacovigilance. To assess safety in pregnancy, we monitored the pregnancy outcomes of all women identified as pregnant during the vaccination campaign through a census. Despite the significant efficacy shown in a phase 3 clinical trial after three doses, we aimed to evaluate the vaccine's efficacy in South Sudan during an epidemic after administering two doses through a case-control study.
RESULTS
Coverage of at least one dose of the Hecolin vaccine after three rounds was estimated at 86% (95% CI: 84-88), with no cases of severe AEFI. Focus groups revealed strong concern about hepatitis E and high confidence and demand for the vaccine. An emulated target trial showed a relative risk of foetal loss between vaccinated and unvaccinated pregnant women at 1.1 (95% CI: 0.7-1.8). Vaccine effectiveness after two doses was estimated at 88.3% (95% CI: 53.8-97.6) using a test-negative design.
CONCLUSION
We found high vaccine coverage, good acceptance, and demand from the population. There was no evidence of increased risk of foetal loss among vaccinated pregnant women. Despite the small number of cases, the reduced dose regimen appeared effective in reducing disease risk in this highly exposed population.
KEY MESSAGE
Studies from the first mass reactive vaccination against hepatitis E demonstrated high coverage and acceptance, no safety issues among pregnant women, and good effectiveness after two doses.
INTRODUCTION
Hepatitis E causes high mortality among pregnant women, with case fatality risks over 30% and adverse fetal outcomes. There is an evidence gap on the safety of the only licensed vaccine, Hecolin®, in pregnancy. In 2015, WHO recommended vaccine use in response to outbreaks, including pregnant women. In 2022, the first mass reactive vaccination campaign against Hepatitis E was conducted in Bentiu displaced persons camp in South Sudan. We aimed to determine whether vaccination against hepatitis E in pregnancy increased the risk of fetal loss in a cohort of vaccinated and unvaccinated pregnant women.
METHODS
An exhaustive pregnancy census was conducted from 16 May 2022 until 30 June 2022 after the second vaccination round, and women were revisited 28 days after delivery date to document the pregnancy outcome. We used an emulated target trial framework to address biases inherent in observational studies. We matched (1:1, with replacement) vaccinated to unvaccinated women on age, gestational age, and vaccination propensity score, and we estimated cumulative incidence functions for fetal loss in vaccinated compared with unvaccinated women using the Nelson-Aalen estimator.
RESULTS
Among 2741 women who had a pregnancy outcome after the start of the vaccination campaign, 67 (2.4%) were vaccinated before conception, 2036 (74.3%) were vaccinated during pregnancy, and 638 (23.3%) were not vaccinated. Among the 2407 women retained in the matched analyses, the cumulative risk of fetal loss in women vaccinated during pregnancy was 6.38% (95% CI 4.93–7.26) compared with 6.26% (3.9–9.19) among unvaccinated women (risk ratio [RR] 1.02 [95% CI 0.64–1.53]). In an analysis restricted to women vaccinated during pregnancy with less than 90 days gestation, the cumulative risk of miscarriage was 11.01% (95% CI 8.45–13.13) among vaccinated women and 11.62% (6.45–17.09) among unvaccinated women (RR 0.95 [95% CI 0.59–1.66]). In sensitivity analyses, we explored the impact of different matching criteria on the estimated RR and found no qualitative differences with the main analyses, with no evidence of increased risk of fetal loss among vaccinated women.
CONCLUSION
We used an emulated target trial methodology with matching to simulate a vaccine trial in pregnant women after a reactive vaccination campaign. This robust analytical method simulating a vaccine trial attempts to control for bias inherent in observational data. We found no evidence for increased risk of fetal loss among women vaccinated during pregnancy.
BACKGROUND
Globally, 9% of people who inject drugs (PWID), a key hepatitis C-infected population, reside in sub-Saharan Africa. In South Africa, hepatitis C seroprevalence in PWID is high. It is almost 84% in Pretoria and hepatitis C genotypes 1 and 3 predominate. Access to hepatitis C care for PWID is inadequate given low referral rates, socio-structural barriers, homelessness and limited access to harm reduction. Traditional care models do not address the needs of this population. We piloted a simplified complete point-of-service care model, a first of its kind in the country and sub-continental region.
METHODS
Community-based recruitment from Pretoria’s PWID population occurred over 11 months. Participants were screened with point-of-care rapid diagnostic tests for HBsAg (Alere Determine™), hepatitis C and HIV antibodies (OraQuick®). Qualitative HCV viremia was confirmed on site with Genedrive® (Sysmex), similarly at week 4, end of treatment and to confirm sustained virological response. Viremic hepatitis C participants were initiated on 12 weeks of daily sofosbuvir and daclatasvir. Harm reduction and adherence support, through directly observed therapy, peer support, a stipend and transport, was provided.
RESULTS
A total of 163 participants were screened for hepatitis C antibody, and 66% were positive with 80 (87%) viremic. An additional 36 confirmed hepatitis C viremic participants were referred. Of those eligible to initiate treatment, 87 (93%) were commenced on sofosbuvir and daclatasvir, with 98% (n = 85) male, 35% (n = 30) HIV co-infected, 1% (n = 1) HBV co-infected and 5% (n = 4) HIV/HBV/HCV triple infected. Some 67% (n = 58) accessed harm reduction packs, 57% (n = 50) opioid substitution therapy and 18% (n = 16) stopped injecting. A per protocol sustained virological response of 90% (n = 51) was achieved with 14% (n = 7) confirmed reinfections following a sustained virological response. HCV RNA qualitative testing performance was acceptable with all sustained virological responses validated against a laboratory assay. Mild adverse effects were reported in 6% (n = 5). Thirty-eight percent (n = 33) of participants were lost to follow-up.
CONCLUSION
In our setting, a simplified point-of-service hepatitis C care model for PWID yielded an acceptable sustained virological response rate. Retention in care and follow-up remains both challenging and central to success. We have demonstrated the utility of a model of care for our country and region to utilize this more community acceptable and simplified practice.