ALTHOUGH Thailand continues to hesitate about bringing in the first dengue vaccine and is a step behind the Philippines in its efforts to control the disease, a Mahidol University researcher still says the Kingdom should wait.

On April 4, the Philippines launched its first public dengue immunisation campaign, which aims to immunise a million nine-year-olds by next year. At present, the Thai government has not proposed similar plans to use the existing dengue vaccine.

The first dengue vaccine produced by Sanofi Pasteur was seen as a momentous advance towards the eradication of the mosquito-borne disease. Apart from the Philippines, Mexico, Brazil and El Salvador have also adopted it.

However, Dr Sutee Yoksan, a vaccine development researcher at Mahidol University’s Institute of Molecular Biosciences, said the vaccine was not good enough to prevent a disease outbreak because it only works in 60 per cent of cases and can only be used on people between the ages of nine and 45.

“The biggest disadvantage is that it can only be used on people above the age of nine, so the Philippines has started vaccinating students of that age. But actually, in order to provide proper protection from dengue, we should start the vaccination programme from a young age,” he said.

Meanwhile, Sutee is developing an alternative vaccine at Mahidol University that he recommends.

Dr Rose Capeding from the Research Institute for Tropical Medicine, who was a key developer of the Sanofi Pasteur vaccine, said the moderate efficiency of the vaccine is not really a big problem.

“Not all vaccines are 100-per-cent effective and this vaccine can cut down on severe dengue cases by 93 per cent. Moreover, if most of the people are immunised, the transmission rate and overall infection rate in society will be greatly reduced,” Cepeding said. “However, we cannot just rely on vaccines to control dengue, we need to use other prevention methods side by side.”

Sutee, however, pointed out that even if the Sanofi Pasteur vaccine can be considered effective enough for a public vaccination campaign, there are still several points of concern that should be considered. For instance, he said, the vaccine was made from genetically engineered dengue and yellow fever viruses, which is why it is only 60-per-cent effective.

“Normally, a vaccine is made from a virus that has been weakened so it cannot do any harm to a person’s health but can teach the antibodies inside us to fight back when we are actually infected,” he said.

“I am now developing a dengue vaccine using the traditional method, which should be able to prevent up to 95 per cent of infections and immunised people will be protected from dengue for life. It can also be used on people of all ages.”

Meanwhile, Disease Control Department director Dr Amnuay Gajeena said Thailand was considering the option of adopting the Sanofi Pasteur vaccine for public use.

“The Food and Drug Administration is considering the registration request for this vaccine, while we carefully consider the vaccine’s effectiveness and worthiness,” Amnuay said. “The effectiveness of this vaccine is still under debate because a dengue vaccine should protect people from all four types of the virus. Hence, we should be judicious about this matter.”

As for the threat of a dengue outbreak, he warned that 2016 would register a record number of infections.

As per the Disease Control Department’s prediction, up to 170,000 people are expected to get dengue this year, with a projected 160 fatalities. This estimate is higher than the outbreak in 2013, when 154,444 people were infected and 136 succumbed to the virus.

“There was a big outbreak of dengue in the latter half of last year, so we are expecting to see this trend continue if nothing is done to control the virus,” Amnuay said.

He said the department was prioritising controlling mosquito populations by killing larvae and spraying repellent. He added that raising awareness was also a useful preventative measure.