Lessons Learned from CDC's Global COVID-19 Early Warning and Response Surveillance System

Public health surveillance perspectives from provincial COVID-19 experiences, South Africa 2021

Previous pandemics, recent outbreaks, and imminent public health events are a clarion call for functional public health surveillance systems that timeously detect public health events, guide interventions, and inform public health policy. We reviewed the Eastern Cape Provincial coronavirus disease 2019 (COVID-19) surveillance approach to determine best practices and opportunities to strengthen public health surveillance. We conducted a document review of COVID-19 surveillance reports, tools and guidelines prepared between March 2020 and November 2021. Iterative content and thematic analysis were applied to identify strengths and shortcomings of provincial COVID-19 surveillance. Strengths and shortcomings of the provincial COVID-19 surveillance process, and human, technical, and technological resources for surveillance were described. The existence of local surveillance networks, local availability of national-level surveillance guidelines, the ability to describe and track COVID-19 epidemiology, and provincial access to a national, web-based centralised COVID-19 surveillance data system were strengths identified. Shortcomings included poor data quality, data disharmony between sub-national reporting levels, under-resourced surveillance capacity at district level, and suboptimal use of the routine surveillance system for COVID-19 surveillance. The review determined the need for a web-based, integrated surveillance system that was agile in meeting evolving surveillance needs and accessible at all health reporting levels for response and decision-making.

Contribution

The review identified opportunities to advance the existing routine public health surveillance system and improve public health surveillance and response. This qualitative review articulates local knowledge that should be translated into strategies and actions to bolster public health preparedness.

Accelerating targeted mosquito control efforts through mobile West Nile virus detection

BACKGROUND

Different mosquito control strategies have been implemented to mitigate or prevent mosquito-related public health situations. Modern mosquito control largely relies on multiple approaches, including targeted, specific treatments. Given this, it is becoming increasingly important to supplement these activities with rapid and mobile diagnostic capacities for mosquito-borne diseases. We aimed to create and test the applicability of a rapid diagnostic system for West Nile virus that can be used under field conditions.

METHODS

In this pilot study, various types of adult mosquito traps were applied within the regular mosquito monitoring activity framework for mosquito control. Then, the captured specimens were used for the detection of West Nile virus RNA under field conditions with a portable qRT-PCR approach within 3-4 h. Then, positive samples were subjected to confirmatory RT-PCR or NGS sequencing in the laboratory to obtain genome information of the virus. We implemented phylogenetic analysis to characterize circulating strains.

RESULTS

A total of 356 mosquito individuals representing 7 species were processed in 54 pools, each containing up to 20 individuals. These pools were tested for the presence of West Nile virus, and two pools tested positive, containing specimens from the Culex pipiens and Anopheles atroparvus mosquito species. As a result of subsequent sequencing, we present the complete genome of West Nile virus and Bagaza virus.

CONCLUSIONS

The rapid identification of infected mosquitoes is the most important component of quick response adulticide or larvicide treatments to prevent human cases. The conceptual framework of real-time surveillance can be optimized for other pathogens and situations not only in relation to West Nile virus. We present an early warning system for mosquito-borne diseases and demonstrate its application to aid rapid-response mosquito control actions.

Global public health intelligence: World Health Organization operational practices

Early warning and response are key to tackle emerging and acute public health risks globally. Therefore, the World Health Organization (WHO) has implemented a robust approach to public health intelligence (PHI) for the global detection, verification and risk assessment of acute public health threats. WHO's PHI operations are underpinned by the International Health Regulations (2005), which require that countries strengthen surveillance efforts, and assess, notify and verify events that may constitute a public health emergency of international concern (PHEIC). PHI activities at WHO are conducted systematically at WHO's headquarters and all six regional offices continuously, throughout every day of the year. We describe four interlinked steps; detection, verification, risk assessment, and reporting and dissemination. For PHI operations, a diverse and interdisciplinary workforce is needed. Overall, PHI is a key feature of the global health architecture and will only become more prominent as the world faces increasing public health threats.