Case Investigation Form from Contact tracing performance during the Ebola virus disease outbreak in Kenema district, Sierra Leone

Contact tracing in an Ebola virus disease (EVD) outbreak is the process of identifying individuals who may have been exposed to infected persons with the virus, followed by monitoring for 21 days (the maximum incubation period) from the date of the most recent exposure. The goal is to achieve early detection and isolation of any new cases in order to prevent further transmission. We performed a retrospective data analysis of 261 probable and confirmed EVD cases in the national EVD database and 2525 contacts in the contact line lists in Kenema district, Sierra Leone between 27 April and 4 September 2014 to assess the performance of contact tracing during the initial stage of the outbreak. The completion rate of the 21-day monitoring period was 89% among the 2525 contacts. However, only 44% of the EVD cases had contacts registered in the contact line list, and 6% of probable or confirmed cases had previously been identified as contacts. Touching the body fluids of the case and having direct physical contact with the body of the case conferred a 9- and 20-fold increased risk of EVD status, respectively. Our findings indicate that incompleteness of contact tracing led to considerable unmonitored transmission in the early months of the epidemic. To improve the performance of early outbreak contact tracing in resource poor settings, our results suggest the need for prioritized contact tracing after careful risk assessment and better alignment of contact line listing with case ascertainment and investigation.This article is part of the themed issue ‘The 2013–2016 West African Ebola epidemic: data, decision-making and disease control’

Challenges encountered during the pandemic response in Yemen Challenges.

Challenges encountered during the pandemic response in Yemen Challenges.</p

Geographical locations of 18 laboratories with PCR, GeneXpert, and genetic sequencing capacity in Yemen by November 2022.

Geographical locations of 18 laboratories with PCR, GeneXpert, and genetic sequencing capacity in Yemen by November 2022.</p

Timelines highlighting important milestones on the evolution of virus in Yemen and period for the establishment of PCR and other laboratories.

Timelines highlighting important milestones on the evolution of virus in Yemen and period for the establishment of PCR and other laboratories.</p

Improvement in the molecular biology capacity in Yemen—Before and after the COVID-19 pandemic.

Improvement in the molecular biology capacity in Yemen—Before and after the COVID-19 pandemic.</p

Performance of two national-level laboratories in external quality assessment scheme.

Performance of two national-level laboratories in external quality assessment scheme.</p

Location and volumes of PCR testing performed for surveillance purpose (orange colour) and for travelers (blue) in Yemen by December 2022.

More testing happened in the southern governorates of the country where points of entry (POEs) are located, noting no positive COVID-19 cases were formally reported from the northern governorates.</p

S1 Dataset -

BackgroundWhen the COVID-19 pandemic was declared, Yemen, a country facing years of conflict had only one laboratory with PCR testing capacity. In this article, we describe the outcome of the implementation of molecular based diagnostics platform in Yemen and highlight the key milestones the country went through to increase access to testing for its populations residing in a geographically vast and politically divided country.MethodsA retrospective assessment of COVID-19 laboratory response activities was done detailing the needs assessment process, timelines, geographical coverage, and outcomes of the activities. Laboratory data was analyzed to construct the geographical locations of COVID-19 testing laboratories and the numbers of tests performed in each facility to highlight the demands of testing for travelers. Finally, we discuss the impact these activities had in enabling the movement of people across international borders for economic gains and in delivery of critical humanitarian aid.OutcomePCR testing capacities in Yemen significantly improved, from one laboratory in Sanaa in April 2020 to 18 facilities across the country by June 2022. In addition, the number of functional Real-Time PCR thermocyclers increased from one to 32, the PCR tests output per day improved from 192 to 6144 tests per day. Results from analysis of laboratory data showed there were four peaks of COVID-19 in Yemen as October 2022. The majority of laboratory tests were performed for travelers than for medical or public health reasons. Demand for laboratory testing in Yemen was generally low and waned over time as the perceived risk of COVID-19 declined, in parallel with rollout of the COVID-19 vaccines.Discussion/ConclusionThe successful expansion of laboratory testing capacity was instrumental in the control and management of COVID-19 cases and critical in the implementation of public response strategies, including restrictions on gathering. Laboratory testing also facilitated the movement of humanitarian agencies and delivery of aid and enabled hundreds of thousands of Yemeni nationals to travel internationally. By virtue of these outcomes, the impact of laboratory strengthening activities was thus felt in the health sector and beyond.</div

Temporal patterns of SARS-COV-2 samples analyzed for the purposes of surveillance in Yemen from April 2020 to December 2022.

Temporal patterns of SARS-COV-2 samples analyzed for the purposes of surveillance in Yemen from April 2020 to December 2022.</p