key: cord-0755553-6ebglgno authors: KC, Sarin; Ananthakrishnan, Aparna; Painter, Christopher; Butani, Dimple; Teerawattananon, Yot title: Research collaboration is needed to inform quarantine policies for health-care workers date: 2021-06-07 journal: Lancet DOI: 10.1016/s0140-6736(21)01224-1 sha: c674bf066ddad2a7d789fa9d4e2717c7c79bf2ae doc_id: 755553 cord_uid: 6ebglgno nan Evidence is weak on global policies and guidelines regarding quarantine and testing measures for vaccinated health-care workers (HCWs) who might have been exposed to patients with COVID-19. Recurring outbreaks have constrained the number of available HCWs, particularly in lowincome and middle-income countries (LMICs). We urge the international community to support development of evidence and evidence-based recommendations on this issue. HCWs face routine and substantial risk of SARS-CoV-2 infection. Many countries have therefore prioritised HCWs for COVID-19 vaccination; however, the vaccines available are not 100% effective, 1 and much remains unknown. Vaccination breakthrough infections and onward transmission among HCWs have been reported. 2 We note that many LMICs will not fully immunise their populations in 2021, leaving the general public at risk of repeated outbreaks and HCWs at risk of exposure. Policy makers must decide whether and how long to quarantine HCWs exposed to COVID-19, how often to test HCWs, and if testing should depend on the presence of symptoms. Evidence and recommendations are needed to help reduce risks to patients, HCWs, and their families. In early May, 2021, eight com munity hospitals in Thailand were temporarily closed because their HCWs, many of whom had been fully vaccinated, were required to quarantine for 14 days. 3 We did a rapid review on this issue for the Thai Ministry of Public Health. To date, only the US Centers for Disease Control and Prevention has released a formal guideline specifically for vaccinated HCWs, which largely depended on the presence of symptoms. 4 Similar policies have been informally adopted in Malaysia and in the Indian state of Odisha, but most countries maintain the same policy regardless of vaccination status. It is unclear whether such guidelines are based on evidence, or if they can be adopted by countries with different profiles, including type of vaccines used, vaccination coverage, local infection rates, and presence of variants of concern. Differential quarantine and testing policies for vaccinated HCWs are becoming increasingly important for many countries with overstretched health-care systems, such as India, Nepal, Brazil, and Thailand. A study of HCWs that considers vaccination status, vaccine type or brand, and their effectiveness, and that takes into account new variants, is warranted. Such research could help individual countries develop optimal quarantine and testing strategies that minimise risks while meeting health-care demands. As several LMICs have fully vaccinated their HCWs, research-informed policy recommendations might be possible by use of data from LMICs alone. However, given the urgency of this issue, we call for solidarity from the global scientific community to research and generate evidence to inform quarantine policies for vaccinated HCWs, similar to that shown for COVID-19 treatments in the Solidarity Trial. COVID-19 vaccine coverage in health-care workers in England and effectiveness of BNT162b2 mRNA vaccine against infection (SIREN): a prospective, multicentre, cohort study TTSH COVID-19 cluster grows to 9 people; 2 wards locked down to stem spread 8 Thai hospitals closed after patients conceal facts about their COVID-19 exposure Updated healthcare infection prevention and control recommendations in response to COVID-19 vaccination We declare no competing interests. No specific funding was received for this research. The Health Intervention and Technology Assessment Program (HITAP) is funded by the Thailand Research Fund. HITAP's international work is supported by the International Decision Support Initiative (iDSI). iDSI is funded by the Bill & Melinda Gates Foundation, the UK's Department for International Development, and the Rockefeller Foundation. HITAP has also been supported by the Health Systems Research Institute to study the challenges of developing a monitoring and evaluation framework for COVID-19 vaccination policy in Thailand, and by the National Research Council of Thailand for an initiative around COVID-19 vaccination policy research in Asia.