METHODS: This was a web-based cross-sectional study conducted among the public in Malaysia between August to October 2022. All Malaysian adults over 18 years of age were included. Knowledge on home quarantine instructions and COVID-19 warning signs were measured using "True," "False," or "I'm not sure", while attitude towards home quarantine instructions was measured using a five-point Likert Scale. The questionnaire was initially constructed in English and then translated into the national language, Bahasa Malaysia. Face and content validation were performed. The internal consistency of the questionnaire was found to be satisfactory.

RESULTS: 1,036 respondents were analyzed, comprised mostly of females (743, 71.6%) with a history of COVID-19 (673, 64.9%). In the knowledge domain, more than 80% of the respondents answered 9 out of 11 home quarantine instructions statements correctly. 457 (44.1%) were unaware or unsure about the minimum distance of the infected individual's bed from the rest of the occupants in a shared bedroom. The respondents reported relatively weaker knowledge in identifying uncommon warning signs of COVID-19 deterioration, including anuria (162, 44.5%), ingestion problems (191, 52.5%), and immobility (195, 53.6%). In the attitude domain, more than 90% of respondents answered correctly in 8 out of 9 questions. Respondents with a previous history of COVID-19 infections had better knowledge than COVID-19 infection-naïve individuals towards both home quarantine instructions and COVID-19 warning signs.