Informing the pandemic response: the role of the WHO's COVID-19 Weekly Epidemiological Update

On 31 December 2019, the Municipal Health Commission of Wuhan, China, reported a cluster of atypical pneumonia cases. On 5 January 2020, the WHO publicly released a Disease Outbreak News (DON) report, providing information about the pneumonia cases, implemented response interventions, and WHO's risk assessment and advice on public health and social measures. Following 9 additional DON reports and 209 daily situation reports, on 17 August 2020, WHO published the first edition of the COVID-19 Weekly Epidemiological Update (WEU). On 1 September 2023, the 158th edition of the WEU was published on WHO's website, marking its final issue. Since then, the WEU has been replaced by comprehensive global epidemiological updates on COVID-19 released every 4 weeks. During the span of its publication, the webpage that hosts the WEU and the COVID-19 Operational Updates was accessed annually over 1.4 million times on average, with visits originating from more than 100 countries. This article provides an in-depth analysis of the WEU process, from data collection to publication, focusing on the scope, technical details, main features, underlying methods, impact and limitations. We also discuss WHO's experience in disseminating epidemiological information on the COVID-19 pandemic at the global level and provide recommendations for enhancing collaboration and information sharing to support future health emergency responses.

COVID-19 Mortality and Progress Toward Vaccinating Older Adults - World Health Organization, Worldwide, 2020-2022

After the emergence of SARS-CoV-2 in late 2019, transmission expanded globally, and on January 30, 2020, COVID-19 was declared a public health emergency of international concern.* Analysis of the early Wuhan, China outbreak (1), subsequently confirmed by multiple other studies (2,3), found that 80% of deaths occurred among persons aged ≥60 years. In anticipation of the time needed for the global vaccine supply to meet all needs, the World Health Organization (WHO) published the Strategic Advisory Group of Experts on Immunization (SAGE) Values Framework and a roadmap for prioritizing use of COVID-19 vaccines in late 2020 (4,5), followed by a strategy brief to outline urgent actions in October 2021.^† WHO described the general principles, objectives, and priorities needed to support country planning of vaccine rollout to minimize severe disease and death. A July 2022 update to the strategy brief^§ prioritized vaccination of populations at increased risk, including older adults,^¶ with the goal of 100% coverage with a complete COVID-19 vaccination series** for at-risk populations. Using available public data on COVID-19 mortality (reported deaths and model estimates) for 2020 and 2021 and the most recent reported COVID-19 vaccination coverage data from WHO, investigators performed descriptive analyses to examine age-specific mortality and global vaccination rollout among older adults (as defined by each country), stratified by country World Bank income status. Data quality and COVID-19 death reporting frequency varied by data source; however, persons aged ≥60 years accounted for >80% of the overall COVID-19 mortality across all income groups, with upper- and lower-middle-income countries accounting for 80% of the overall estimated excess mortality. Effective COVID-19 vaccines were authorized for use in December 2020, with global supply scaled up sufficiently to meet country needs by late 2021 (6). COVID-19 vaccines are safe and highly effective in reducing severe COVID-19, hospitalizations, and mortality (7,8); nevertheless, country-reported median completed primary series coverage among adults aged ≥60 years only reached 76% by the end of 2022, substantially below the WHO goal, especially in middle- and low-income countries. Increased efforts are needed to increase primary series and booster dose coverage among all older adults as recommended by WHO and national health authorities.

Outcomes of cholera and measles outbreak alerts in the Democratic Republic of Congo

Setting

In 1995, a rapid response project for humanitarian and medical emergencies, including outbreak responses, named 'Pool d'Urgence Congo' (PUC), was implemented in the Democratic Republic of Congo by Médecins Sans Frontières.

Objective

To assess the outcomes of cholera and measles outbreak alerts that were received in the PUC surveillance system between 2016 and 2018.

Design

This was a retrospective cross-sectional study.

Results

Overall, 459 outbreak alerts were detected, respectively 69% and 31% for cholera and measles. Of these, 32% were actively detected and 68% passively detected. Most alerts (90%) required no intervention and 10% of alerts had an intervention. There were 25% investigations that were not carried out despite thresholds being met; 17% interventions were not performed, the main reported reason being PUC operational capacity was exceeded. Confirmed cholera and measles outbreaks that met an investigation threshold comprised respectively 90% and 76% of alerts; 59% of measles investigations were followed by a delayed outbreak response of ⩾14 days (n = 10 outbreaks).

Conclusion

Some alerts for cholera and measles outbreaks that were detected in the PUC system did not lead to a response even when required; the main reported reason was limited operational capacity to respond to all of them.