Implementation of targeted cholera response activities, Cameroon.

Objective: To describe the implementation of case-area targeted interventions to reduce cholera transmission using a rapid, localized response in Kribi district, Cameroon. Methods: We used a cross-sectional design to study the implementation of case-area targeted interventions. We initiated interventions after rapid diagnostic test confirmation of a case of cholera. We targeted households within a 100-250 metre perimeter around the index case (spatial targeting). The interventions package included: health promotion, oral cholera vaccination, antibiotic chemoprophylaxis for nonimmunized direct contacts, point-of-use water treatment and active case-finding. Findings: We implemented eight targeted intervention packages in four health areas of Kribi between 17 September 2020 and 16 October 2020. We visited 1533 households (range: 7-544 per case-area) hosting 5877 individuals (range: 7-1687 per case-area). The average time from detection of the index case to implementation of interventions was 3.4 days (range: 1-7). Oral cholera vaccination increased overall immunization coverage in Kribi from 49.2% (2771/5621 people) to 79.3% (4456/5621 people). Interventions also led to the detection and prompt management of eight suspected cases of cholera, five of whom had severe dehydration. Stool culture was positive for Vibrio cholerae O1 in four cases. The average time from onset of symptoms to admission of a person with cholera to a health facility was 1.2 days. Conclusion: Despite challenges, we successfully implemented targeted interventions at the tail-end of a cholera epidemic, after which no further cases were reported in Kribi up until week 49 of 2021. The effectiveness of case-area targeted interventions in stopping or reducing cholera transmission needs further investigation.

A mixed-methods investigation to understand and improve the scaled-up infection prevention and control in primary care health facilities during the Ebola virus disease epidemic in Sierra Leone.

BACKGROUND: The 2014-2015 Ebola epidemic in West Africa became a humanitarian crisis that exposed significant gaps in infection prevention and control (IPC) capacity in primary care facilities in Sierra Leone. Operational partners recognized the national gap and rapidly scaled-up an IPC training and infrastructure package. This prompted us to carry out a mixed-methods research study which aimed to evaluate adherence to IPC practices and understand how to improve IPC at the primary care level, where most cases of Ebola were initially presenting. The study was carried out during the national peak of the epidemic. DISCUSSION: We successfully carried out a rapid response research study that produced several expected and unexpected findings that were used to guide IPC measures during the epidemic. Although many research challenges were similar to those found when conducting research in low-resource settings, the presence of Ebola added risks to safety and security of data collectors, as well as a need to balance research activities with the imperative of response to a humanitarian crisis. A participatory approach that attempted to unify levels of the response from community upwards helped overcome the risk of lack of trust in an environment where Ebola had damaged relations between communities and the health system. CONCLUSION: In the context of a national epidemic, research needs to be focused, appropriately resourced, and responsive to needs. The partnership between local academics and a humanitarian organization helped facilitate access to study sites and approvals that allowed the research to be carried out quickly and safely, and for findings to be shared in response forums with the best chance of being taken up in real-time.

Early detection of cholera epidemics to support control in fragile states: estimation of delays and potential epidemic sizes.

BACKGROUND: Cholera epidemics continue to challenge disease control, particularly in fragile and conflict-affected states. Rapid detection and response to small cholera clusters is key for efficient control before an epidemic propagates. To understand the capacity for early response in fragile states, we investigated delays in outbreak detection, investigation, response, and laboratory confirmation, and we estimated epidemic sizes. We assessed predictors of delays, and annual changes in response time. METHODS: We compiled a list of cholera outbreaks in fragile and conflict-affected states from 2008 to 2019. We searched for peer-reviewed articles and epidemiological reports. We evaluated delays from the dates of symptom onset of the primary case, and the earliest dates of outbreak detection, investigation, response, and confirmation. Information on how the outbreak was alerted was summarized. A branching process model was used to estimate epidemic size at each delay. Regression models were used to investigate the association between predictors and delays to response. RESULTS: Seventy-six outbreaks from 34 countries were included. Median delays spanned 1-2 weeks: from symptom onset of the primary case to presentation at the health facility (5 days, IQR 5-5), detection (5 days, IQR 5-6), investigation (7 days, IQR 5.8-13.3), response (10 days, IQR 7-18), and confirmation (11 days, IQR 7-16). In the model simulation, the median delay to response (10 days) with 3 seed cases led to a median epidemic size of 12 cases (upper range, 47) and 8% of outbreaks ≥ 20 cases (increasing to 32% with a 30-day delay to response). Increased outbreak size at detection (10 seed cases) and a 10-day median delay to response resulted in an epidemic size of 34 cases (upper range 67 cases) and < 1% of outbreaks < 20 cases. We estimated an annual global decrease in delay to response of 5.2% (95% CI 0.5-9.6, p = 0.03). Outbreaks signaled by immediate alerts were associated with a reduction in delay to response of 39.3% (95% CI 5.7-61.0, p = 0.03). CONCLUSIONS: From 2008 to 2019, median delays from symptom onset of the primary case to case presentation and to response were 5 days and 10 days, respectively. Our model simulations suggest that depending on the outbreak size (3 versus 10 seed cases), in 8 to 99% of scenarios, a 10-day delay to response would result in large clusters that would be difficult to contain. Improving the delay to response involves rethinking the integration at local levels of event-based detection, rapid diagnostic testing for cluster validation, and integrated alert, investigation, and response.

Response strategies for COVID-19 epidemics in African settings: a mathematical modelling study.

BACKGROUND: The health impact of COVID-19 may differ in African settings as compared to countries in Europe or China due to demographic, epidemiological, environmental and socio-economic factors. We evaluated strategies to reduce SARS-CoV-2 burden in African countries, so as to support decisions that balance minimising mortality, protecting health services and safeguarding livelihoods. METHODS: We used a Susceptible-Exposed-Infectious-Recovered mathematical model, stratified by age, to predict the evolution of COVID-19 epidemics in three countries representing a range of age distributions in Africa (from oldest to youngest average age: Mauritius, Nigeria and Niger), under various effectiveness assumptions for combinations of different non-pharmaceutical interventions: self-isolation of symptomatic people, physical distancing and 'shielding' (physical isolation) of the high-risk population. We adapted model parameters to better represent uncertainty about what might be expected in African populations, in particular by shifting the distribution of severity risk towards younger ages and increasing the case-fatality ratio. We also present sensitivity analyses for key model parameters subject to uncertainty. RESULTS: We predicted median symptomatic attack rates over the first 12 months of 23% (Niger) to 42% (Mauritius), peaking at 2-4 months, if epidemics were unmitigated. Self-isolation while symptomatic had a maximum impact of about 30% on reducing severe cases, while the impact of physical distancing varied widely depending on percent contact reduction and R0. The effect of shielding high-risk people, e.g. by rehousing them in physical isolation, was sensitive mainly to residual contact with low-risk people, and to a lesser extent to contact among shielded individuals. Mitigation strategies incorporating self-isolation of symptomatic individuals, moderate physical distancing and high uptake of shielding reduced predicted peak bed demand and mortality by around 50%. Lockdowns delayed epidemics by about 3 months. Estimates were sensitive to differences in age-specific social mixing patterns, as published in the literature, and assumptions on transmissibility, infectiousness of asymptomatic cases and risk of severe disease or death by age. CONCLUSIONS: In African settings, as elsewhere, current evidence suggests large COVID-19 epidemics are expected. However, African countries have fewer means to suppress transmission and manage cases. We found that self-isolation of symptomatic persons and general physical distancing are unlikely to avert very large epidemics, unless distancing takes the form of stringent lockdown measures. However, both interventions help to mitigate the epidemic. Shielding of high-risk individuals can reduce health service demand and, even more markedly, mortality if it features high uptake and low contact of shielded and unshielded people, with no increase in contact among shielded people. Strategies combining self-isolation, moderate physical distancing and shielding could achieve substantial reductions in mortality in African countries. Temporary lockdowns, where socioeconomically acceptable, can help gain crucial time for planning and expanding health service capacity.

Estimating the infection and case fatality ratio for coronavirus disease (COVID-19) using age-adjusted data from the outbreak on the Diamond Princess cruise ship, February 2020.

Adjusting for delay from confirmation to death, we estimated case and infection fatality ratios (CFR, IFR) for coronavirus disease (COVID-19) on the Diamond Princess ship as 2.6% (95% confidence interval (CI): 0.89-6.7) and 1.3% (95% CI: 0.38-3.6), respectively. Comparing deaths on board with expected deaths based on naive CFR estimates from China, we estimated CFR and IFR in China to be 1.2% (95% CI: 0.3-2.7) and 0.6% (95% CI: 0.2-1.3), respectively.

The ethical contours of research in crisis settings: five practical considerations for academic institutional review boards and researchers.

The number of research studies in the humanitarian field is rising. It is imperative, therefore, that institutional review boards (IRBs) consider carefully the additional risks present in crisis contexts to ensure that the highest ethical standards are upheld. Ethical guidelines should represent better the specific issues inherent to research among populations grappling with armed conflict, disasters triggered by natural hazards, or health-related emergencies. This paper seeks to describe five issues particular to humanitarian settings that IRBs should deliberate and on which they should provide recommendations to overcome associated challenges: staged reviews of protocols in acute emergencies; flexible reviews of modification requests; addressing violence and the traumatic experiences of participants; difficulties in attaining meaningful informed consent among populations dependent on aid; and ensuring reviews are knowledgeable of populations' needs. Considering these matters when reviewing protocols will yield more ethically sound research in humanitarian settings and hold researchers accountable to appropriate ethical standards.

"We and the nurses are now working with one voice": How community leaders and health committee members describe their role in Sierra Leone's Ebola response.

BACKGROUND: Across low-income settings, community volunteers and health committee members support the formal health system - both routinely and amid emergencies - by engaging in health services such as referrals and health education. During the 2014-2015 Ebola epidemic, emerging reports suggest that community engagement was instrumental in interrupting transmission. Nevertheless, literature regarding community volunteers' roles during emergencies generally, and Ebola specifically, is scarce. This research outlines what this cadre of the workforce did, how they coped, and the facilitators and barriers they faced to providing care in Sierra Leone. METHODS: Thirteen focus group discussions (FGD) were conducted with community members (including members of Health Management Committees (HMC)) near the height of the Ebola epidemic in two districts of Sierra Leone: Bo and Kenema. Conducted in either Krio or Mende, each FGD lasted an average of two hours and was led by a trained moderator who was accompanied by a note taker. All FGDs were audio recorded, transcribed, and translated into English by the data collection team. Analysis followed a modified framework approach, which entailed coding (both inductive and deductive), arrangement of codes into themes, and drafting, distribution and discussion of analytic summaries across the study team. RESULTS: Community volunteers and HMC members described engaging in labor-related tasks (e.g. building isolation structures, digging graves) and administrative/community-outreach tasks (e.g. screening, contact tracing, and encouraging care seeking within facilities). Through their dual orientation as community members and as individuals linked to the health system, respondents described building community trust and support for Ebola prevention and treatment, while also enabling formal health workers to better understand and address people's fears and needs. Community volunteers' main concerns included inadequate communication with - and a sense of being forgotten by - the health system, negative perceptions of their role within their communities, and concerns regarding the amount and nature of their compensation. DISCUSSION & CONCLUSION: Respondents described commitment to supporting their health system and their communities during the Ebola crisis. The health system could more effectively harness the potential of local responders by recognizing community strengths and weaknesses, as well as community volunteers' motivations and limitations. Clarifying the roles, responsibilities, and remuneration of health volunteers to the recipients themselves, facility-based staff, and the wider community will enable organizations that partner with health committees to bolster trust, manage expectations, and reinforce collaboration.

Assessment of Community Event-Based Surveillance for Ebola Virus Disease, Sierra Leone, 2015.

In 2015, community event-based surveillance (CEBS) was implemented in Sierra Leone to assist with the detection of Ebola virus disease (EVD) cases. We assessed the sensitivity of CEBS for finding EVD cases during a 7-month period, and in a 6-week subanalysis, we assessed the timeliness of reporting cases with no known epidemiologic links at time of detection. Of the 12,126 CEBS reports, 287 (2%) met the suspected case definition, and 16 were confirmed positive. CEBS detected 30% (16/53) of the EVD cases identified during the study period. During the subanalysis, CEBS staff identified 4 of 6 cases with no epidemiologic links. These CEBS-detected cases were identified more rapidly than those detected by the national surveillance system; however, too few cases were detected to determine system timeliness. Although CEBS detected EVD cases, it largely generated false alerts. Future versions of community-based surveillance could improve case detection through increased staff training and community engagement.

A plan for community event-based surveillance to reduce Ebola transmission - Sierra Leone, 2014-2015.

Ebola virus disease (Ebola) was first detected in Sierra Leone in May 2014 and was likely introduced into the eastern part of the country from Guinea. The disease spread westward, eventually affecting Freetown, Sierra Leone's densely populated capital. By December 2014, Sierra Leone had more Ebola cases than Guinea and Liberia, the other two West African countries that have experienced widespread transmission. As the epidemic intensified through the summer and fall, an increasing number of infected persons were not being detected by the county's surveillance system until they had died. Instead of being found early in the disease course and quickly isolated, these persons remained in their communities throughout their illness, likely spreading the disease.

Integrated community case management: quality of care and adherence to medication in Beneshangul-Gumuz Region, Ethiopia.

BACKGROUND: The International Rescue Committee (IRC) supports implementation of integrated Community Case Management (iCCM) in all 20 woredas (districts) of Benishangul Gumuz Region (BSG) in Ethiopia. OBJECTIVES: To identify the gaps in the provision of quality iCCM services provided by Health Extension Workers (HEWs) and to assess caregivers' adherence to prescribed medicines for children under five years of age. METHODS: We conducted a cross-sectional descriptive study with both quantitative and qualitative study methods. We interviewed 233 HEWs and 384 caregivers, reviewed HEW records of 1,082 cases, and organized eight focus groups. RESULTS: Most cases (98%) seen by HEWs were children 2-59 months old, and 85% of the HEWs did not see any sick young infant. The HEWs' knowledge on assessments and classification and need for referral of cases was above 80%. However; some reported challenges, especially in carrying out assessment correctly and not checking for danger signs. Over 90% of caretakers reported compliance with HEWs' prescription. CONCLUSION: Partners have successfully deployed trained HEWs who can deliver iCCM according to protocol; however, additional support is needed to assure a supply of medicines and to mobilize demand for services, especially for young infants.

Disruption to water supply and waterborne communicable diseases in northeast Syria: a spatiotemporal analysis.

BACKGROUND: In Syria, disruption to water and sanitation systems, together with poor access to vaccination, forced displacement and overcrowding contribute to increases in waterborne diseases (WBDs). The aim of this study is to perform a spatiotemporal analysis to investigate potential associations between interruptions to water, sanitation, and hygiene (WASH) and WBDs in northeast Syria using data collected by the Early Warning Alert and Response Network (EWARN) from Deir-ez-Zor, Raqqa, Hassakeh and parts of Aleppo governorates. METHODS: We reviewed the literature databases of MEDLINE and Google Scholar and the updates of ReliefWeb to obtain information on acute disruptions and attacks against water infrastructure in northeast Syria between January 2015 and June 2021. The EWARN weekly trends of five syndromes representing waterborne diseases were plotted and analysed to identify time trends and the influence of these disruptions. To investigate a potential relationship, the Wilcoxon rank sum test was used to compare districts with and without disruptions. Time series analyses were carried out on major disruptions to analyse their effect on WBD incidence. RESULTS: The literature review found several instances where water infrastructure was attacked or disrupted, suggesting that water has been deliberately targeted by both state and non-state actors in northeast Syria throughout the conflict. Over time, there was an overall upwards trend of other acute diarrhoea (OAD, p < 0.001), but downwards trends for acute jaundice syndrome, suspected typhoid fever and acute bloody diarrhoea. For the major disruption of the Alouk water plant, an interrupted time series analysis did not find a strong correlation between the disruption and changes in disease incidence in the weeks following the incident, but long-term increases in WBD were observed. CONCLUSIONS: While no strong immediate correlation could be established between disruptions to WASH and WBDs in northeast Syria, further research is essential to explore the impact of conflict-associated damage to civil infrastructure including WASH. This is vital though challenging given confounding factors which affect both WASH and WBDs in contexts like northeast Syria. As such, research which includes exploration of mitigation after damage to WASH is essential to improve understanding of impacts on quantity and quality of WASH. More granular research which explores the origin of cases of WBDs and how such communities are affected by challenges to WASH is needed. One step towards research on this, is the implementation of adequate reporting mechanisms for real time tracking of the WASH attacks, damages, direct effects, and likely impact in conjunction with environmental and public health bodies and surveillance systems.

Rapidly adapted community health strategies to prevent treatment interruption and improve COVID-19 detection for Syrian refugees and the host population with hypertension and diabetes in Jordan.

BACKGROUND: We evaluated community health volunteer (CHV) strategies to prevent non-communicable disease (NCD) care disruption and promote coronavirus disease 2019 (COVID-19) detection among Syrian refugees and vulnerable Jordanians, as the pandemic started. METHODS: Alongside medication delivery, CHVs called patients monthly to assess stockouts and adherence, provide self-management and psychosocial support, and screen and refer for complications and COVID-19 testing. Cohort analysis was undertaken of stockouts, adherence, complications and suspected COVID-19. Multivariable models of disease control assessed predictors and non-inferiority of the strategy pre-/post-initiation. Cost-efficiency and patient/staff interviews assessed implementation. RESULTS: Overall, 1119 patients were monitored over 8 mo. The mean monthly proportion of stockouts was 4.9%. The monthly proportion non-adherent (past 5/30 d) remained below 5%; 204 (18.1%) patients had complications, with 63 requiring secondary care. Mean systolic blood pressure and random blood glucose remained stable. For hypertensive disease control, age 41-65 y (OR 0.46, 95% CI 0.2 to 0.78) and with diabetes (OR 0.73, 95% CI 0.54 to 0.98) had decreased odds, and with baseline control had increased odds (OR 3.08, 95% CI 2.31 to 4.13). Cumulative suspected COVID-19 incidence (2.3/1000 population) was suggestive of ongoing transmission. While cost-efficient (108 US${\$}$/patient/year), funding secondary care was challenging. CONCLUSIONS: During multiple crises, CHVs prevented care disruption and reinforced COVID-19 detection.

What we do know (and could know) about estimating population sizes of internally displaced people.

The estimation of population denominators of internally displaced people (IDP) and other crisis-affected populations is a foundational step that facilitates all humanitarian assistance. However, the humanitarian system remains somewhat tolerant of irregular and inaccurate estimates of population size and composition, particularly of IDPs. In this commentary, we review how humanitarian organizations currently approach the estimation of IDP populations, and how field approaches and analytical methodologies can be improved and integrated.

Country differences in transmissibility, age distribution and case-fatality of SARS-CoV-2: a global ecological analysis.

Objectives The first COVID-19 pandemic waves in many low-income countries appeared milder than initially forecasted. We conducted a country-level ecological study to describe patterns in key SARS-CoV-2 outcomes by country and region and explore associations with potential explanatory factors, including population age structure and prior exposure to endemic parasitic infections. Methods We collected publicly available data and compared them using standardisation techniques. We then explored the association between exposures and outcomes using random forest and linear regression. We adjusted for potential confounders and plausible effect modifications. Results While mean time-varying reproduction number was highest in the European and Americas regions, median age of death was lower in the Africa region, with a broadly similar case-fatality ratio. Population age was strongly associated with mean (ß=0.01, 95% CI, 0.005, 0.011) and median age of cases (ß=-0.40, 95% CI, -0.53, -0.26) and deaths (ß= 0.40, 95% CI, 0.17, 0.62). Conclusions Population age seems an important country-level factor explaining both transmissibility and age distribution of observed cases and deaths. Endemic infections seem unlikely, from this analysis, to be key drivers of the variation in observed epidemic trends. Our study was limited by the availability of outcome data and its causally uncertain ecological design.

Inference is bliss: Simulation for power estimation for an observational study of a cholera outbreak intervention.

BACKGROUND: The evaluation of ring vaccination and other outbreak-containment interventions during severe and rapidly-evolving epidemics presents a challenge for the choice of a feasible study design, and subsequently, for the estimation of statistical power. To support a future evaluation of a case-area targeted intervention against cholera, we have proposed a prospective observational study design to estimate the association between the strength of implementation of this intervention across several small outbreaks (occurring within geographically delineated clusters around primary and secondary cases named 'rings') and its effectiveness (defined as a reduction in cholera incidence). We describe here a strategy combining mathematical modelling and simulation to estimate power for a prospective observational study. METHODOLOGY AND PRINCIPAL FINDINGS: The strategy combines stochastic modelling of transmission and the direct and indirect effects of the intervention in a set of rings, with a simulation of the study analysis on the model results. We found that targeting 80 to 100 rings was required to achieve power ≥80%, using a basic reproduction number of 2.0 and a dispersion coefficient of 1.0-1.5. CONCLUSIONS: This power estimation strategy is feasible to implement for observational study designs which aim to evaluate outbreak containment for other pathogens in geographically or socially defined rings.

Heavy-tailed sexual contact networks and monkeypox epidemiology in the global outbreak, 2022.

The outbreak of monkeypox across non-endemic regions confirmed in May 2022 shows epidemiological features distinct from previously imported outbreaks, most notably its observed growth and predominance amongst men who have sex with men (MSM). We use a transmission model fitted to empirical sexual partnership data to show that the heavy-tailed sexual partnership distribution, in which a handful of individuals have disproportionately many partners, can explain the sustained growth of monkeypox among MSM despite the absence of such patterns previously. We suggest that the basic reproduction number (R0) for monkeypox over the MSM sexual network may be substantially above 1, which poses challenges to outbreak containment. Ensuring support and tailored messaging to facilitate prevention and early detection among MSM with high numbers of partners is warranted.

Effectiveness of case-area targeted interventions including vaccination on the control of epidemic cholera: protocol for a prospective observational study.

INTRODUCTION: Cholera outbreaks in fragile settings are prone to rapid expansion. Case-area targeted interventions (CATIs) have been proposed as a rapid and efficient response strategy to halt or substantially reduce the size of small outbreaks. CATI aims to deliver synergistic interventions (eg, water, sanitation, and hygiene interventions, vaccination, and antibiotic chemoprophylaxis) to households in a 100-250 m 'ring' around primary outbreak cases. METHODS AND ANALYSIS: We report on a protocol for a prospective observational study of the effectiveness of CATI. Médecins Sans Frontières (MSF) plans to implement CATI in the Democratic Republic of the Congo (DRC), Cameroon, Niger and Zimbabwe. This study will run in parallel to each implementation. The primary outcome is the cumulative incidence of cholera in each CATI ring. CATI will be triggered immediately on notification of a case in a new area. As with most real-world interventions, there will be delays to response as the strategy is rolled out. We will compare the cumulative incidence among rings as a function of response delay, as a proxy for performance. Cross-sectional household surveys will measure population-based coverage. Cohort studies will measure effects on reducing incidence among household contacts and changes in antimicrobial resistance. ETHICS AND DISSEMINATION: The ethics review boards of MSF and the London School of Hygiene and Tropical Medicine have approved a generic protocol. The DRC and Niger-specific versions have been approved by the respective national ethics review boards. Approvals are in process for Cameroon and Zimbabwe. The study findings will be disseminated to the networks of national cholera control actors and the Global Task Force for Cholera Control using meetings and policy briefs, to the scientific community using journal articles, and to communities via community meetings.

Ciprofloxacin-resistant Shigella sonnei among men who have sex with men, Canada, 2010.

In 2010, we observed isolates with matching pulsed-field gel electrophoresis patterns from 13 cases of ciprofloxacin-resistant Shigella sonnei in Montréal. We report on the emergence of this resistance type and a study of resistance mechanisms. The investigation suggested local transmission among men who have sex with men associated with sex venues.