Descriptive epidemiology of the cholera outbreak in Zimbabwe 2018-2019: role of multi-sectorial approach in cholera epidemic control.

OBJECTIVES: This study was conducted to explore the epidemiology and microbiological pattern of the cholera outbreaks that occurred in Zimbabwe from 2018 to 2019. STUDY SETTING AND DESIGN: This descriptive study used secondary data of 9971 out of 10 730 suspected cases from the Zimbabwean National Diseases Surveillance system and microbiology data of 241 out of 371 patients from the National Microbiology Reference Laboratory in Harare, for the period 5 September 2018 and 3 January 2019. Descriptive analysis was performed to describe the characteristics of the outbreak in terms of person, place and time. RESULTS: A cumulative total of 10 730 suspected, 371 laboratory-confirmed cholera cases and 68 deaths were reported in Zimbabwe through the situation analysis report (sitrep). The attack rate during the outbreak was 174.6 per 100 000 with a case fatality rate of 0.63%. Most cases seen were among adults from Harare province. Antimicrobial sensitivity testing results showed that a multidrug resistant strain of Vibrio cholerae O1, Ogawa serotype was responsible for the outbreak. The treatment of cases was changed from the standard recommended medicine ciprofloxacin to azithromycin as confirmed by the antimicrobial sensitivity test results. Strategies employed to contain the outbreak included mass oral cholera vaccination in the hotspot areas of Harare, provision of improved and appropriate sanitation measures, provision of safe and adequate water, chlorination of water and improved waste management practice. CONCLUSIONS: The recurrence of a cholera outbreak is a global concern, especially with the emergence of multi-drug resistant strains of the causal organism. Improving water, sanitation, hygiene infrastructure, health system strengthening measures and inter-sectoral collaboration in responding to the cholera outbreak was key to controlling the outbreak.

Genomic epidemiology and the role of international and regional travel in the SARS-CoV-2 epidemic in Zimbabwe: a retrospective study of routinely collected surveillance data.

BACKGROUND: Advances in SARS-CoV-2 sequencing have enabled identification of new variants, tracking of its evolution, and monitoring of its spread. We aimed to use whole genome sequencing to describe the molecular epidemiology of the SARS-CoV-2 outbreak and to inform the implementation of effective public health interventions for control in Zimbabwe. METHODS: We performed a retrospective study of nasopharyngeal samples collected from nine laboratories in Zimbabwe between March 20 and Oct 16, 2020. Samples were taken as a result of quarantine procedures for international arrivals or to test for infection in people who were symptomatic or close contacts of positive cases. Samples that had a cycle threshold of less than 30 in the diagnostic PCR test were processed for sequencing. We began our analysis in July, 2020 (120 days since the first case), with a follow-up in October, 2020 (at 210 days since the first case). The phylogenetic relationship of the genome sequences within Zimbabwe and global samples was established using maximum likelihood and Bayesian methods. FINDINGS: Of 92 299 nasopharyngeal samples collected during the study period, 8099 were PCR-positive and 328 were available for sequencing, with 156 passing sequence quality control. 83 (53%) of 156 were from female participants. At least 26 independent introductions of SARS-CoV-2 into Zimbabwe in the first 210 days were associated with 12 global lineages. 151 (97%) of 156 had the Asp614Gly mutation in the spike protein. Most cases, 93 (60%), were imported from outside Zimbabwe. Community transmission was reported 6 days after the onset of the outbreak. INTERPRETATION: Initial public health interventions delayed onset of SARS-CoV-2 community transmission after the introduction of the virus from international and regional migration in Zimbabwe. Global whole genome sequence data are essential to reveal major routes of spread and guide intervention strategies. FUNDING: WHO, Africa CDC, Biotechnology and Biological Sciences Research Council, Medical Research Council, National Institute for Health Research, and Genome Research Limited.

Use of geographic information systems web mapping application to support active case search to guide public health and social measures in the context of COVID-19 in Zimbabwe: a preliminary report to guide replication of methods in similar resource settings.

INTRODUCTION: the new coronavirus (COVID-19) that emerged from Wuhan, Hubei Province of China in December 2019, causing severe acute respiratory syndrome (SARS) has fast spread across the entire globe, with most countries struggling to slow and reduce the spread of the virus through rapid screening, testing, isolation, case management, contact tracing, implementing social distancing and lockdowns. This has been shown to be a major factor in countries that have been successful in containing COVID-19 transmission. Early detection of cases is important, and the use of geospatial technology can support to detect and easily identify potential hotspots that will require timely response. The use of spatial analysis with geographic information systems (GIS) had proved to be effective in providing timely and effective solutions in supporting epidemic response and pandemics over the years. It has developed and evolved rapidly with a complete technological tool for representing data, model construction, visualization and platform construction among others. METHODS: we conducted a geospatial analysis to develop a web mapping application using ArcMap and ArcGIS online to guide and support active case search of potential COVID-19 cases, within 500m radius of COVID-19 confirmed cases to improve detection and testing of suspected cases. RESULTS: the web mapping application tool guides the active case search teams in the field, with clear boundaries on the houses to be visited within 500-meter radius of confirmed positive cases, to conduct active case search of all cases of severe acute respiratory illnesses (SARI), acute respiratory illnesses (ARI), pneumonia etc, to detect and test for COVID-19 towards containing the pandemic. CONCLUSION: the use of GIS and spatial statistical tools have become an important and valuable tool in decision-making and, more importantly, guiding health care professional and other stakeholders in the response being carried out in a more coherent and easy manner. It has proven to be effective in supporting the active case search process to rapidly detect, test and isolate cases during the process, towards containing the COVID-19 pandemic.