Pandemic special studies & early investigations networks: a key component of pandemic preparedness and effective response

With emergence of a novel pathogen, pandemic special studies can rapidly assess transmissibility, estimate population susceptibility/immunity and infection severity and estimate vaccine effectiveness. A suite of standardised ‘master’ special studies protocols were developed by WHO for influenza and implemented following the emergence of MERS-CoV, Zika virus and SARS-CoV-2. We report on the lessons learned from the COVID-19 pandemic and readiness needs for future pandemics. 

The WHO Unity Studies initiative supported countries globally, especially low-and middle-income countries (LMICs), to conduct standardised special sero-epidemiological studies with a focus on capacity building and equity. Early in the COVID-19 pandemic, ten ‘master’ protocols were developed and WHO provided technical support, serological assays, funding and training to implement these studies. WHO encouraged the sharing of early results for evidence-based action. An independent evaluation of the Unity Studies Initiative was conducted.  

As of 31 December 2021, 103 WHO Member States (103/ 194=53%) had implemented at least one sero-epidemiological investigation using WHO's Unity studies master protocols, 63% (65/103) being LMIC. The population-based seroprevalence studies (44%) and the first few cases (FFX) and household transmission investigation (HHTI) (22%) protocols were most adopted.  Results from these study types were pooled, meta-analysed and published to inform global and regional risk assessment and response. The external evaluation informed on the usefulness of study findings in guiding national and global COVID-19 response strategies, capacity built from engagement, and management and support. Acute needs identified included long-term investment and commitment, appropriate pre-approvals, data platforms for rapid data sharing and a toolkit and training for quality implementation, analysis and reporting of results.  

Special studies and early investigations remain critical epidemiological tools in all resource settings for early and ongoing characterisation of novel infectious pathogens. The Unity Studies initiative created equitable research opportunities, connected researchers and expertise across countries and facilitated study implementation.  The setting-up and nurturing of regional networks of target countries, building on existing local capacity developed during COVID-19, will enable regular and quality implementation of standardised special studies. We recommend the design of country-specific pre-planned and pre-approved “sleeping” studies which are exercised in inter-pandemic periods and/or ready to be activated when required.