In a Facebook post on Friday, Dr Yong Poovorawan explained that previously the virus’s incubation period was around five or six days.
However, he said, the Omicron variant takes only three days to incubate, which gives the immune system very little time to fight back.
Hence, he said, it is easier and quicker to get infected.
Dr Yong added that immunity provided by vaccines may not prevent infection, but can reduce the severity of the disease.
He believes 90% of Thais have built up their immunity either with vaccines or previous infections. However, he said, more than 70% of them may get infected again but with fewer symptoms.
He also said that eventually, people will have to live with the disease because it will become commonplace like influenza.
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