In a Facebook post on Saturday, Dr Yong Poovorawan said cases began rising in mid-November and will hit a peak in January.
However, he said the numbers will start dropping from mid-February before picking up again during the rainy season from June to September.
Hence, he said, it is important for people to boost their immunity right away instead of waiting. He added that though the vaccines available in Thailand target older variants, they are still very effective.
Dr Yong said that though vaccines targeting specific variants may offer more immunity, this protection will reduce over time. But, he said, the more shots and boosters people get, the better chance they will have of preventing severe symptoms.
Hence, he said, everybody should get at least three shots and the fourth one within six months.
Those who received their fourth jab more than six months ago could also get a fifth one because their immunity will have started dropping.
Dr Yong went on to say that Omicron and its BA.1, BA.2, BA.2.75, BA.4 and BA.5 subvariants are still most prevalent in Thailand and had infected nearly 70% of the population. He was citing a study from blood samples in Chonburi.
As for news of Deltacron infections, he said it will not be a problem in Thailand because the main variant is still Omicron.
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