Coverage survey and lessons learned from a pre-emptive cholera vaccination campaign in urban and rural communities affected by landslides and floods in Freetown Sierra Leone.

BACKGROUND: On 14 August 2017, massive landslides and floods hit Freetown (Sierra Leone). More than 1,000 people lost their lives while approximately 6,000 people were displaced. The areas most affected included parts of the town with challenged access to basic water and sanitation facilities, with communal water sources likely contaminated by the disaster. To avert a possible cholera outbreak following this emergency, the Ministry of Health and Sanitation (MoHS), supported by the World Health Organization (WHO) and international partners, including Médecins Sans Frontières (MSF) and UNICEF, launched a two-dose pre-emptive vaccination campaign using Euvichol™, an oral cholera vaccine (OCV). METHODS: We conducted a stratified cluster survey to estimate vaccination coverage during the OCV campaign and also monitor adverse events. The study population - subsequently stratified by age group and residence area type (urban/rural) - included all individuals aged 1 year or older, living in one of the 25 communities targeted for vaccination. RESULTS: In total 3,115 households were visited, 7,189 individuals interviewed; 2,822 (39%) people in rural and 4,367 (61%) in urban areas. The two-dose vaccination coverage was 56% (95% confidence interval (CI): 51.0-61.5), 44% (95%CI: 35.2-53.0) in rural and 57% (95%CI: 51.6-62.8) in urban areas. Vaccination coverage with at least one dose was 82% (95%CI: 77.3-85.5), 61% (95%CI: 52.0-70.2) in rural and 83% (95%CI: 78.5-87.1) in urban areas. CONCLUSIONS: The Freetown OCV campaign exemplified a timely public health intervention to prevent a cholera outbreak, even if coverage was lower than expected. We hypothesised that vaccination coverage in Freetown was sufficient in providing at least short-term immunity to the population. However, long-term interventions to ensure access to safe water and sanitation are needed.

Maternal health after Ebola: unmet needs and barriers to healthcare in rural Sierra Leone.

Sierra Leone has the world's highest estimated maternal mortality. Following the 2014-16 Ebola outbreak, we described health outcomes and health-seeking behaviour amongst pregnant women to inform health policy. In October 2016-January 2017, we conducted a sequential mixed-methods study in urban and rural areas of Tonkolili District comprising: household survey targeting women who had given birth since onset of the Ebola outbreak; structured interviews at rural sites investigating maternal deaths and reporting; and in-depth interviews (IDIs) targeting mothers, community leaders and health workers. We selected 30 clusters in each area: by random GPS points (urban) and by random village selection stratified by population size (rural). We collected data on health-seeking behaviours, barriers to healthcare, childbirth and outcomes using structured questionnaires. IDIs exploring topics identified through the survey were conducted with a purposive sample and analysed thematically. We surveyed 608 women and conducted 29 structured and 72 IDIs. Barriers, including costs of healthcare and physical inaccessibility of healthcare facilities, delayed or prevented 90% [95% confidence interval (CI): 80-95] (rural) vs 59% (95% CI: 48-68) (urban) pregnant women from receiving healthcare. Despite a general preference for biomedical care, 48% of rural and 31% of urban women gave birth outside of a health facility; of those, just 4% and 34%, respectively received skilled assistance. Women expressed mistrust of healthcare workers (HCWs) primarily due to payment demanded for 'free' healthcare. HCWs described lack of pay and poor conditions precluding provision of quality care. Twenty percent of women reported labour complications. Twenty-eight percent of villages had materials to record maternal deaths. Pregnant women faced important barriers to care, particularly in rural areas, leading to high preventable mortality and morbidity. Women wanted to access healthcare, but services available were often costly, unreachable and poor quality. We recommend urgent interventions, including health promotion, free healthcare access and strengthening rural services to address barriers to maternal healthcare.

Seroprevalence and risk factors of recent infection with hepatitis E virus during an acute outbreak in an urban setting in Chad, 2017.

BACKGROUND: From September 2016-April 2017, Am Timan, Chad, experienced a large HEV outbreak in an urban setting with a limited impact in terms of morbidity and mortality. To better understand HEV epidemiology in this context, we estimated the seroprevalence of anti-HEV antibodies (IgM and IgG) and assessed the risk factors for recent HEV infections (positive anti-HEV IgM) during this outbreak. METHODS: A serological survey using simple random sampling was implemented in Am Timan at the tail-end of the outbreak (sample size aim = 384 household). Household members provided us with blood samples and household heads answered questions around water, sanitation and hygiene practices and animal ownership. Blood samples were tested for HEV IgG and IgM antibodies using Enzyme-Immune-Assay (EIA). We calculated weighted prevalence estimates and prevalence ratios (PRs) for possible risk factors for recent infection using multivariate Cox regression. RESULTS: We included 241 households (1529 participants). IgM prevalence decreased with age: 12.6% (< 5 years) to 4.3% (> 15 years). IgG prevalence increased with age: 23.5% (< 5 years) to 75.9% (> 15 years). Risk factors for recent HEV infections included: sharing the sanitation facility with other HHs (PR 1.72; 95%CI: 1.08-2.73), not systematically using soap for HW (PR 1.85; 95%CI: 1.30-2.63) and having animals sleeping inside the compound (PR 1.69; 95%CI: 1.15-2.50). CONCLUSIONS: Evidence suggests that Am Timan was already highly endemic for HEV before the outbreak, potentially explaining the limited extent of the outbreak. Recent infection with HEV was linked to household level exposures. Future HEV outbreak response must include ensuring access to safe water, and reducing household level transmission through active hygiene and sanitation promotion activities.

Learning from water treatment and hygiene interventions in response to a hepatitis E outbreak in an open setting in Chad.

In September 2016, Médecins Sans Frontières responded to a hepatitis E (HEV) outbreak in Chad by implementing water treatment and hygiene interventions. To evaluate the coverage and use of these interventions, we conducted a cross-sectional study in the community. Our results showed that 99% of households interviewed had received a hygiene kit from us, aimed at improving water handling practice and personal hygiene and almost all respondents had heard messages about preventing jaundice and handwashing. Acceptance of chlorination of drinking water was also very high, although at the time of interview, we were only able to measure a safe free residual chlorine level (free chlorine residual (FRC) ≥0.2 mg/L) in 43% of households. Households which had refilled water containers within the last 18 hours, had sourced water from private wells or had poured water into a previously empty container, were all more likely to have a safe FRC level. In this open setting, we were able to achieve high coverage for chlorination, hygiene messaging and hygiene kit ownership; however, a review of our technical practice is needed in order to maintain safe FRC levels in drinking water in households, particularly when water is collected from multiple sources, stored and mixed with older water.

A large outbreak of Hepatitis E virus genotype 1 infection in an urban setting in Chad likely linked to household level transmission factors, 2016-2017.

BACKGROUND: In September 2016, three acutely jaundiced (AJS) pregnant women were admitted to Am Timan Hospital, eastern Chad. We described the outbreak and conducted a case test-negative study to identify risk factors for this genotype of HEV in an acute outbreak setting. METHODS: Active case finding using a community based surveillance network identified suspected AJS cases. Pregnant or visibly ill AJS cases presenting at hospital were tested with Assure® IgM HEV rapid diagnostic tests (RDTs) and some with Polymerase Chain Reaction (PCR) in Amsterdam; confirmed cases were RDT-positive and controls were RDT-negative. All answered questions around: demographics, household makeup, area of residence, handwashing practices, water collection behaviour and clinical presentation. We calculated unadjusted odds ratios (ORs) and 95% confidence intervals (95% CI). RESULTS: Between September and April 2017, 1443 AJS cases (1293 confirmed) were detected in the town(attack rate: 2%; estimated 65,000 population). PCR testing confirmed HEV genotype 1e. HEV RDTs were used for 250 AJS cases; 100 (40%) were confirmed. Risk factors for HEV infection, included: having at least two children under the age of 5 years (OR 2.1, 95%CI 1.1-4.3), having another household member with jaundice (OR 2.4, 95%CI 0.90-6.3) and, with borderline significance, living in the neighbourhoods of Riad (OR 3.8, 95%CI 1.0-1.8) or Ridina (OR 3.3, 95%CI 1.0-12.6). Cases were more likely to present with vomiting (OR 3.2, 9%CI 1.4-7.9) than controls; possibly due to selection bias. Cases were non-significantly less likely to report always washing hands before meals compared with controls (OR 0.33, 95%CI 0.1-1.1). DISCUSSION: Our study suggests household factors and area of residence (possibly linked to access to water and sanitation) play a role in HEV transmission; which could inform future outbreak responses. Ongoing sero-prevalence studies will elucidate more aspects of transmission dynamics of this virus with genotype 1e.