Only a place that has been free from a Covid-19 case for 28 days can be considered a safe zone, Dr Yong Poovorawan, expert virologist at Chulalongkorn University, said.
The doctor said through his social media account that the a safe zone is always a place which is free from a disease for two times the incubation period. The concept was used in the time of Sars, Mers and also Ebola.
For example in the case of Sars, a safe zone is an area where a Sars case is not found for 20 days, since the incubation period is 10 days.
For Covid-19, the safe area must be areas where Covid-19 is not found for 28 days, since its incubation period is 14 days.
Thai returnees switch border crossings after virus outbreak at Sadao
Thai nationals in Malaysia continued to flow through Songkhla’s Padang Besar border checkpoint on Thursday (April 23), afterthe Sadao checkpoint was temporarily closed on Wednesday.
Thais seeking to return from Malaysia have been redirected to Padang Basar while the Sadao checkpoint is disinfected, following the discovery that two Immigration police officers there had been infected with Covid-19.
Thursday marked the sixth day since five Thai-Malaysian border checkpoints were opened to allow Thais stranded in Malaysia to return. Mandatory quarantine measures are in place for all returnees.