Lertwanichwattana T.Srivanichakorn S.Noknoy S.Na Ratchaseema S.S.Phanuphak N.Wongthavarawat K.Siriussawakul A.Srinonprasert V.Leelahavarong P.Chevaisrakul P.Lumjiaktase P.Kumpitak A.Phromsri N.Sirisinsuk Y.Kietdumrongwong P.Aramrattana A.Rangsin R.Mahidol University2025-04-012025-04-012025-04-01American Journal of Public Health Vol.115 No.4 (2025) , 605-61600900036https://repository.li.mahidol.ac.th/handle/20.500.14594/108530Objectives. To determine the overall mortality and risk factors of COVID-19 patients who were admitted to the Home Isolation (HI) program in Bangkok, Thailand, during the epidemic crisis in 2021. Methods. We conducted a retrospective cohort study using the data from a government telehealth application from July to December 2021. The vital status was verified from the government database on September 20, 2022. We used survival analysis to analyze the 28-day mortality and independently associated factors. Results. Of 90 854 reported cases, the average age was 37.27 years, and half were men. Initial symptoms included being asymptomatic (51.66%), having mild symptoms (35.60%), or experiencing severe symptoms requiring nonurgent (11.27%) or urgent referral (1.47%). The 28-day mortality rate was 0.80%. Factors associated with 28-day mortality included older age, male gender, higher body mass index, severity of initial symptoms, and time to admission. Conclusions. The Home Isolation program was able to manage a high volume of patients, including severe cases, exceeding its initial design. Thailand’s COVID-19 mortality rate remained relatively low compared with other countries. Proactive bed surge planning and continuous plan improvement were crucial for future preparedness. (Am J Public Health. 2025;115(4):605–616. https://doi.org/10.2105/AJPH.2024.307922).MedicineArticleSCOPUS10.2105/AJPH.2024.3079222-s2.0-10500025793915410048