inclusion criteria: - general doctors, specialist doctors, nurses and midwives who are in charge of handling covid-19 patients or working in covid-19 referral hospitals for at least the last 3 months - 20-65 years old - willing to sign informed consent - willing to follow the research to completion - bmi > 23 kg/m2

inclusion criteria: - general doctors, specialist doctors, nurses and midwives who are in charge of handling covid-19 patients or working in covid-19 referral hospitals for at least the last 3 months - 20-65 years old - willing to sign informed consent - willing to follow the research to completion - bmi > 23 kg/m2