• Alternative observational designs to estimate the effectiveness of one dose of oral cholera vaccine in Lusaka, Zambia

      Ferreras, E; Blake, A; Chewe, O; Mwaba, J; Zulu, G; Poncin, M; Rakesh, A; Page, AL; Quilici, ML; Azman, AS; et al. (Cambridge University Press, 2020-03-13)
      We conducted a matched case-control (MCC), test-negative case-control (TNCC) and case-cohort study in 2016 in Lusaka, Zambia, following a mass vaccination campaign. Confirmed cholera cases served as cases in all three study designs. In the TNCC, control-subjects were cases with negative cholera culture and polymerase chain reaction results. Matched controls by age and sex were selected among neighbours of the confirmed cases in the MCC study. For the case-cohort study, we recruited a cohort of randomly selected individuals living in areas considered at-risk of cholera. We recruited 211 suspected cases (66 confirmed cholera cases and 145 non-cholera diarrhoea cases), 1055 matched controls and a cohort of 921. Adjusted vaccine effectiveness of one dose of oral cholera vaccine (OCV) was 88.9% (95% confidence interval (CI) 42.7-97.8) in the MCC study, 80.2% (95% CI: 16.9-95.3) in the TNCC design and 89.4% (95% CI: 64.6-96.9) in the case-cohort study. Three study designs confirmed the short-term effectiveness of single dose OCV. Major healthcare-seeking behaviour bias did not appear to affect our estimates. Most of the protection among vaccinated individuals could be attributed to the direct effect of the vaccine.
    • Alternative observational designs to estimate the effectiveness of one dose of oral cholera vaccine in Lusaka, Zambia

      Ferreras, E; Blake, A; Chewe, O; Mwaba, J; Zulu, G; Poncin, M; Rakesh, A; Page, AL; Quilici, ML; Azman, AS; et al. (Cambridge University Press, 2020-03-13)
      We conducted a matched case-control (MCC), test-negative case-control (TNCC) and case-cohort study in 2016 in Lusaka, Zambia, following a mass vaccination campaign. Confirmed cholera cases served as cases in all three study designs. In the TNCC, control-subjects were cases with negative cholera culture and polymerase chain reaction results. Matched controls by age and sex were selected among neighbours of the confirmed cases in the MCC study. For the case-cohort study, we recruited a cohort of randomly selected individuals living in areas considered at-risk of cholera. We recruited 211 suspected cases (66 confirmed cholera cases and 145 non-cholera diarrhoea cases), 1055 matched controls and a cohort of 921. Adjusted vaccine effectiveness of one dose of oral cholera vaccine (OCV) was 88.9% (95% confidence interval (CI) 42.7–97.8) in the MCC study, 80.2% (95% CI: 16.9–95.3) in the TNCC design and 89.4% (95% CI: 64.6–96.9) in the case-cohort study. Three study designs confirmed the short-term effectiveness of single dose OCV. Major healthcare-seeking behaviour bias did not appear to affect our estimates. Most of the protection among vaccinated individuals could be attributed to the direct effect of the vaccine.
    • Diphtheria outbreak with high mortality in northeastern Nigeria

      Besa, N C; Coldiron, M E; Bakri, A; Raji, A; Nsuami, M J; Rousseau, C; Hurtado, N; Porten, K; Epicentre, Paris, France. (Cambridge University Press, 2013-07-18)
      SUMMARY A diphtheria outbreak occurred from February to November 2011 in the village of Kimba and its surrounding settlements, in Borno State, northeastern Nigeria. We conducted a retrospective outbreak investigation in Kimba village and the surrounding settlements to better describe the extent and clinical characteristics of this outbreak. Ninety-eight cases met the criteria of the case definition of diphtheria, 63 (64·3%) of whom were children aged <10 years; 98% of cases had never been immunized against diphtheria. None of the 98 cases received diphtheria antitoxin, penicillin, or erythromycin during their illness. The overall case-fatality ratio was 21·4%, and was highest in children aged 0-4 years (42·9%). Low rates of immunization, delayed clinical recognition of diphtheria and absence of treatment with antitoxin and appropriate antibiotics contributed to this epidemic and its severity.
    • Does Research Through Structured Operational Research and Training (SORT IT) Courses Impact Policy and Practice?

      Kumar, AMV; Shewade, HD; Tripathy, JP; Guillerm, N; Tayler-Smith, K; Dar Berger, S; Bissell, K; Reid, AJ; Zachariah, R; Harries, AD (Cambridge University Press, 2016-03-21)
    • Ensuring On-site Ebola Patient Monitoring and Follow-up: Development of a Laboratory Structure Embedded in an Ebola Treatment Center.

      Williams, A; Amand, M; Van den Bergh, R; De Clerck, H; Antierens, A; Chaillet, P (Cambridge University Press, 2019-12-01)
      The capacity to rapidly distinguish Ebola virus disease from other infectious diseases and to monitor biochemistry and viremia levels is crucial to the clinical management of suspected Ebola virus disease cases. This article describes the design and practical considerations of a laboratory straddling the high- and low-risk zones of an Ebola treatment center to produce timely diagnostic and clinical results for informed case management of Ebola virus disease in real-life conditions. This innovation may be of relevance for actors requiring flexible laboratory implementation in contexts of high-communicability, high-lethality disease outbreaks.
    • Epidemiological and clinical aspects of human Brucella suis infection in Polynesia

      Guerrier, G; Daronat, J M; Morisse, L; Yvon, J F; Pappas, G; Epicentre, Paris, France; Agence de Santé, Mata Utu, Wallis, France; Institute of Continuing Medical Education of Ioannina, Greece; International Society of Chemotherapy Zoonoses Working Group, London, UK (Cambridge University Press, 2011-06-21)
      High brucellosis seroprevalence rates in domestic swine herds have been reported in Wallis and Futuna Islands and are associated with a significant burden of human infection by Brucella suis, a species that is rarely incriminated in human disease. Between 2003 and 2010, seven patients had a positive blood culture for B. suis biovar 1, 11 symptomatic patients had a positive Rose Bengal test (RBT) and a positive serum agglutination test (SAT) and three asymptomatic cases were found to be positive for RBT, SAT or ELISA IgM (after systematic screening of 52 family members of 15 index cases). Overall, Brucella infection was diagnosed in 21 people, corresponding to a mean annual incidence of 19 cases/100 000 inhabitants. Compared to series of patients infected with other more commonly encountered Brucella spp. such as B. melitensis and B. abortus, clinical presentation and percentage and distribution of complications were similar, apart from a marked observation of significantly increased median alanine aminotransferase levels, 20 times greater than upper normal rates, but not accompanied by any particular hepatic pathology. Wallis and Futuna, where people live in close proximity to animals and where the cultural significance of pig-raising precludes the implementation of adequate veterinary preventive measures, thus represents one of the few known B. suis foci worldwide and allows for evaluation of the peculiarities of this infection.
    • Episodic outbreaks bias estimates of age-specific force of infection: a corrected method using measles as an example.

      Ferrari, M J; Djibo, A; Grais, RF; Grenfell, B T; Bjørnstad, O N; Center for Infectious Disease Dynamics, Penn State University, PA 16802, USA. mferrari@psu.edu (Cambridge University Press, 2010-01)
      Understanding age-specific differences in infection rates can be important in predicting the magnitude of and mortality in outbreaks and targeting age groups for vaccination programmes. Standard methods to estimate age-specific rates assume that the age-specific force of infection is constant in time. However, this assumption may easily be violated in the face of a highly variable outbreak history, as recently observed for acute immunizing infections like measles, in strongly seasonal settings. Here we investigate the biases that result from ignoring such fluctuations in incidence and present a correction based on the epidemic history. We apply the method to data from a measles outbreak in Niamey, Niger and show that, despite a bimodal age distribution of cases, the estimated age-specific force of infection is unimodal and concentrated in young children (<5 years) consistent with previous analyses of age-specific rates in the region.
    • Extended use or reuse of single-use surgical masks and filtering face-piece respirators during the coronavirus disease 2019 (COVID-19) pandemic: A rapid systematic review.

      Toomey, E; Conway, Y; Burton, C; Smith, S; Smalle, M; Chan, X; Adisesh, A; Tanveer, S; Ross, L; Thomson, I; et al. (Cambridge University Press, 2020-10-08)
      Background: Shortages of personal protective equipment during the coronavirus disease 2019 (COVID-19) pandemic have led to the extended use or reuse of single-use respirators and surgical masks by frontline healthcare workers. The evidence base underpinning such practices warrants examination. Objectives: To synthesize current guidance and systematic review evidence on extended use, reuse, or reprocessing of single-use surgical masks or filtering face-piece respirators. Data sources: We used the World Health Organization, the European Centre for Disease Prevention and Control, the US Centers for Disease Control and Prevention, and Public Health England websites to identify guidance. We used Medline, PubMed, Epistemonikos, Cochrane Database, and preprint servers for systematic reviews. Methods: Two reviewers conducted screening and data extraction. The quality of included systematic reviews was appraised using AMSTAR-2. Findings were narratively synthesized. Results: In total, 6 guidance documents were identified. Levels of detail and consistency across documents varied. They included 4 high-quality systematic reviews: 3 focused on reprocessing (decontamination) of N95 respirators and 1 focused on reprocessing of surgical masks. Vaporized hydrogen peroxide and ultraviolet germicidal irradiation were highlighted as the most promising reprocessing methods, but evidence on the relative efficacy and safety of different methods was limited. We found no well-established methods for reprocessing respirators at scale. Conclusions: Evidence on the impact of extended use and reuse of surgical masks and respirators is limited, and gaps and inconsistencies exist in current guidance. Where extended use or reuse is being practiced, healthcare organizations should ensure that policies and systems are in place to ensure these practices are carried out safely and in line with available guidance.
    • Health-seeking behaviour and community perceptions of childhood undernutrition and a community management of acute malnutrition (CMAM) programme in rural Bihar, India: a qualitative study.

      Burtscher, D; Burza, S (Cambridge University Press, 2015-03-10)
      Objective Since 2009, Médecins Sans Frontières has implemented a community management of acute malnutrition (CMAM) programme in rural Biraul block, Bihar State, India that has admitted over 10 000 severely malnourished children but has struggled with poor coverage and default rates. With the aim of improving programme outcomes we undertook a qualitative study to understand community perceptions of childhood undernutrition, the CMAM programme and how these affected health-seeking behaviour.
    • The incubation period of hepatitis E genotype 1: insights from pooled analyses of travellers

      Azman, AS; Ciglenecki, I; Oeser, C; Said, B; Tedder, RS; Ijaz, S (Cambridge University Press, 2018-05-24)
      Hepatitis E virus genotype 1 (HEV G1) is an important cause of morbidity and mortality in Africa and Asia. HEV G1's natural history, including the incubation period, remains poorly understood, hindering surveillance efforts and effective control. Using individual-level data from 85 travel-related HEV G1 cases in England and Wales, we estimate the incubation period distribution using survival analysis methods, which allow for appropriate inference when only time ranges, rather than exact times are known for the exposure to HEV and symptom onset. We estimated a 29.8-day (95% confidence interval (CI) 24.1-36.0) median incubation period with 5% of people expected to develop symptoms within 14.3 days (95% CI 10.1-21.7) and 95% within 61.9 days (95% CI 47.4-74.4) of exposure. These estimates can help refine clinical case definitions and inform the design of disease burden and intervention studies.
    • Making Progress Towards Food Security: Evidence from an Intervention in Three Rural Districts of Rwanda

      Nsabuwera, V; Hedt-Gauthier, B; Khogali, M; Edginton, M; Hinderaker, S G; Nisingizwe, M P; Tihabyona, J d D; Sikubwabo, B; Sembagare, S; Habinshuti, A; et al. (Cambridge University Press, 2015-08-06)
      Determining interventions to address food insecurity and poverty, as well as setting targets to be achieved in a specific time period have been a persistent challenge for development practitioners and decision makers. The present study aimed to assess the changes in food access and consumption at the household level after one-year implementation of an integrated food security intervention in three rural districts of Rwanda.
    • Médecins Sans Frontières Experience in Orthopedic Surgery in Postearthquake Haiti in 2010

      Teicher, C L; Alberti, K; Porten, K; Elder, G; Baron, E; Herard, P (Cambridge University Press, 2014-01-15)
      Introduction During January 2010, a 7.0 magnitude earthquake struck Haiti, resulting in death and destruction for hundreds of thousands of people. This study describes the types of orthopedic procedures performed, the options for patient follow-up, and limitations in obtaining outcomes data in an emergency setting. Problem There is not a large body of data that describes larger orthopedic cohorts, especially those focusing on internal fixation surgeries in resource-poor settings in postdisaster regions. This article describes 248 injuries and over 300 procedures carried out in the Médecins Sans Frontières-Orthopedic Centre Paris orthopedic program.
    • Modelling the first dose of measles vaccination: the role of maternal immunity, demographic factors, and delivery systems.

      Metcalf, C J E; Klepac, P; Ferrari, M; Grais, RF F; Djibo, A; Grenfell, B T; Department of Ecology and Evolutionary Biology, Princeton University, NJ 0854, USA. cmetcalf@princeton.edu (Cambridge University Press, 2011-02)
      Measles vaccine efficacy is higher at 12 months than 9 months because of maternal immunity, but delaying vaccination exposes the children most vulnerable to measles mortality to infection. We explored how this trade-off changes as a function of regionally varying epidemiological drivers, e.g. demography, transmission seasonality, and vaccination coverage. High birth rates and low coverage both favour early vaccination, and initiating vaccination at 9-11 months, then switching to 12-14 months can reduce case numbers. Overall however, increasing the age-window of vaccination decreases case numbers relative to vaccinating within a narrow age-window (e.g. 9-11 months). The width of the age-window that minimizes mortality varies as a function of birth rate, vaccination coverage and patterns of access to care. Our results suggest that locally age-targeted strategies, at both national and sub-national scales, tuned to local variation in birth rate, seasonality, and access to care may substantially decrease case numbers and fatalities for routine vaccination.
    • Multidrug-Resistant Surgical Site Infections in a Humanitarian Surgery Project

      Murphy, RA; Okoli, O; Essien, I; Teicher, C; Elder, G; Pena, J; Ronat, JB; Bernabé, KJ (Cambridge University Press, 2016-08-11)
      The epidemiology of surgical site infections (SSIs) in surgical programmes in sub-Saharan Africa is inadequately described. We reviewed deep and organ-space SSIs occurring within a trauma project that had a high-quality microbiology partnership and active follow-up. Included patients underwent orthopaedic surgery in Teme Hospital (Port Harcourt, Nigeria) for trauma and subsequently developed a SSI requiring debridement and microbiological sampling. Data were collected from structured chart reviews and programmatic databases for 103 patients with suspected SSI [79% male, median age 30 years, interquartile range (IQR) 24-37]. SSIs were commonly detected post-discharge with 58% presenting >28 days after surgery. The most common pathogens were: Staphylococcus aureus (34%), Pseudomonas aeruginosa (16%) and Enterobacter cloacae (11%). Thirty-three (32%) of infections were caused by a multidrug-resistant (MDR) pathogen, including 15 patients with methicillin-resistant S. aureus. Antibiotics were initiated empirically for 43% of patients and after culture and sensitivity report in 32%. The median number of additional surgeries performed in patients with SSI was 5 (IQR 2-6), one patient died (1%), and amputation was performed or recommended in three patients. Our findings suggest the need for active long-term monitoring of SSIs, particularly those associated with MDR organisms, resulting in increased costs for readmission surgery and treatment with late-generation antibiotics.
    • A qualitative investigation of adherence to nutritional therapy in malnourished adult AIDS patients in Kenya

      Dibari, Filippo; Bahwere, Paluku; Le Gall, Isabelle; Guerrero, Saul; Mwaniki, David; Seal, Andrew; Valid International, Oxford, UK; UCL Centre for International Health and Development, Institute of Child Health, London, UK; MSF-France, Nairobi, Kenya/Paris, France; Centre for Public Health, Kenya Medical Research Institute, KEMRI/CPHR, Nairobi, Kenya; Academy for Educational Development/Regional Office for Eastern and Central Africa, Nairobi, Kenya (Cambridge University Press, 2011-02-04)
      To understand factors affecting the compliance of malnourished, HIV-positive adults with a nutritional protocol using ready-to-use therapeutic food (RUTF; Plumpy'nut®).
    • Risk factors for cholera transmission in Haiti during inter-peak periods: insights to improve current control strategies from two case-control studies

      Grandesso, F; Allan, M; Jean-Simon, P S J; Boncy, J; Blake, A; Pierre, R; Alberti, K P; Munger, A; Elder, G; Olson, D; et al. (Cambridge University Press, 2013-10-11)
      SUMMARY Two community-based density case-control studies were performed to assess risk factors for cholera transmission during inter-peak periods of the ongoing epidemic in two Haitian urban settings, Gonaives and Carrefour. The strongest associations were: close contact with cholera patients (sharing latrines, visiting cholera patients, helping someone with diarrhoea), eating food from street vendors and washing dishes with untreated water. Protective factors were: drinking chlorinated water, receiving prevention messages via television, church or training sessions, and high household socioeconomic level. These findings suggest that, in addition to contaminated water, factors related to direct and indirect inter-human contact play an important role in cholera transmission during inter-peak periods. In order to reduce cholera transmission in Haiti intensive preventive measures such as hygiene promotion and awareness campaigns should be implemented during inter-peak lulls, when prevention activities are typically scaled back.
    • Spatial dynamics of meningococcal meningitis in Niger: observed patterns in comparison with measles

      Bharti, N; Broutin, H; Grais, RF F; Ferrari, M J; Djibo, A; Tatem, A J; Grenfell, B T; Department of Ecology and Evolutionary Biology and Center for Health and Wellbeing, Woodrow Wilson School of Public and International Affairs, Princeton University, Princeton NJ, USA; MIVEGEC, UMR CNRS 5290, IRD 224, UM1, UM2, Montpellier, France; Epicentre, Paris, France; Department of Biology, Department of Statistics, and Center for Infectious Disease Dynamics, Penn State University, PA, USA; Ministry of Health, Niamey, Niger; Emerging Pathogens Institute and Department of Geography, University of Florida, Gainesville FL, USA; Fogarty International Center, National Institutes of Health, Bethesda MD, USA (Cambridge University Press, 2011-10-05)
      SUMMARYThroughout the African meningitis belt, meningococcal meningitis outbreaks occur only during the dry season. Measles in Niger exhibits similar seasonality, where increased population density during the dry season probably escalates measles transmission. Because meningococcal meningitis and measles are both directly transmitted, we propose that host aggregation also impacts the transmission of meningococcal meningitis. Although climate affects broad meningococcal meningitis seasonality, we focus on the less examined role of human density at a finer spatial scale. By analysing spatial patterns of suspected cases of meningococcal meningitis, we show fewer absences of suspected cases in districts along primary roads, similar to measles fadeouts in the same Nigerien metapopulation. We further show that, following periods during no suspected cases, districts with high reappearance rates of meningococcal meningitis also have high measles reintroduction rates. Despite many biological and epidemiological differences, similar seasonal and spatial patterns emerge from the dynamics of both diseases. This analysis enhances our understanding of spatial patterns and disease transmission and suggests hotspots for infection and potential target areas for meningococcal meningitis surveillance and intervention.
    • The Use of Interpreters in Medical Triage During a Refugee Mass-Gathering Incident in Europe

      Alexakis, L; Papachristou, A; Baruzzi, C; Konstantinou, A (Cambridge University Press, 2017-07-28)
      Introduction During a refugees' mass-gathering incident in Kos Island, Greece, Médecins Sans Frontières (MSF; Brussels, Belgium) teams provided emergency medical care. A case report of the event focusing on difficulties encountered by the interpreters during triage and emergency response was prepared.