Public health authorities said Wednesday they were accelerating a review of the controversial Dengvaxia dengue vaccine's efficiency after its use was halted in the Philippines last week.
Although the vaccine was registered in Thailand on Sept 30 last year after winning approval from the Food and Drug Administration (FDA), it has yet to be included in the country's standard immunisation list.
Authorities are still in the process of reviewing information about the vaccine including the epidemiological data and assessing whether it will be cost-effective to make the vaccine a part of the country's standard immunisation package, said Dr Suwanchai Watthanayingcharoen, director-general of the Department of Disease Control (DDC).
Last week, the Department of Health in the Philippines suspended the use of Dengvaxia produced by French drug giant Sanofi.
The Philippines has halted the distribution of the vaccine and ordered an investigation into the immunisation of more than 730,000 children who received the jab following an announcement by Sanofi that it could worsen the disease in some cases if given to those not previously infected by the dengue virus, according to news agencies.
Dr Suwanchai said while waiting for the WHO to formally react to the matter, all the DDC could do is assure people who have already acquired dengue immunity after a previous infection that they will experience less severe symptoms after getting the shot.
"Although Thailand has already begun giving the dengue vaccine to interested people, mainly at privately run hospitals, the vaccine is only seen as one measure to control dengue and it still has to be used all along with other key disease prevention measures," he said.
The best course of action is still a combination of eradicating the sources of mosquitoes including stagnant water and preventing mosquito bites by using mosquito repellent products because these are seen as very effective measures against not only dengue but also other mosquito-borne diseases including Zika, he said.
Public Health Minister Piyasakol Sakolsatayadorn also said the ministry has not actually focused on the use of a dengue vaccine as a key means of preventing the disease.
As for people who have already received dengue vaccine shots, he said, they should not worry too much about the possible side effects that have been reported in the news because not everyone will develop them.
The DDC is implementing a surveillance programme on possible dengue vaccine side effects and discussing and developing guideline on administering the jab, said the minister.