1. 1. Nalbandian A, Sehgal K, Gupta A, et al. Post-acute COVID-19 syndrome. Nat Med. 2021; 27:601-615.
2. 2. National Institute for Health and Care Excellence. COVID-19 Rapid Guideline: Managing the Long-Term Effects of COVID-19).(NG188). Evidence reviews 2 and 3: prevalence. 2020. https://www.nice.org.uk/guidance/ng188 (accessed June 8, 2021).
3. 3. Cares-Marambio K, Montenegro-Jiménez Y, TorresCastro R, Vera-Uribe R, Torralba Y, Alsina-Restoy X, Vasconcello-Castillo L, Valiro J. Prevalence of potential respiratory symptoms in survivors of hospital admission after coronavirus disease 2019 (COVID-19): A systematic review and meta-analysis. Chron Respir Dis. 2021; 18:147997312110022.
4. 4. World Health Organization. Laboratory testing for coronavirus disease (COVID-19) in suspected human cases: interim guidance. https://apps.who.int/iris/handle/10665/331501(19 March 2020) (accessed Jun 25, 2021).
5. 5. Government of India; Ministry of Health and Family Welfare; Directorate General of Health Services (EMR Division). Clinical Management Protocol for COVID19 dated 27/06/2020. https://www.mohfw.gov.in/pdf/ClinicalManagementProtocolforCOVID19.pdf (accessed Jul 19, 2021).