The rising incidence of dengue fever in Asean has prompted health experts to call for a collective regional action to fight the fastest- growing mosquito-borne disease.
Given the scale of migration within the 10-nation bloc, the best efforts to curb the spread of the virus in one country can be undone by slow notice of outbreaks across the border, they said on the sidelines of a conference in Bangkok to mark the annual Asean Dengue Day yesterday.
"It is a regional problem," said Dr Pratap Singhasivanon, secretary- general of the South-east Asian Ministers of Education Organisation's tropical medicine network, who added that data sharing between Asean countries is too slow. "You need real-time information… the data that is important today may be useless after three days."
Dengue, which spreads fast in dense urban spaces, causes nausea, fatigue, bleeding and even death. There is no specific treatment for the disease, which is spread by the Aedes mosquito.
An estimated 390 million dengue infections occur every year across the world, the bulk of them in Asia.
Number of dengue infections every year across the world; the bulk of them in Asia
The economic burden of the disease in 2013
Number of cases, up to June 4, in the Philippines, which is one of the hardest-hit countries
A study published in the Lancet in April says the disease imposed an economic burden of US$8.9 billion (S$12 billion) in 2013.
One of the hardest-hit countries last year was the Philippines, which saw a 64.8 per cent spike in suspected cases - to 200,415 - and 598 deaths. It has recorded 49,904 cases up to June 4. In April, it became the first Asean country to start mass vaccinations against dengue.
Infection figures so far this year continue to be cause for worry. Thailand, which had earlier warned of an outbreak exceeding 166,000 cases this year, recorded 18,337 cases and 16 deaths from Jan 1 to June 7.
Malaysia has recorded 46,856 cases up to May 14, an increase of 8.6 per cent compared to the same period last year. The fever has caused 109 deaths in that period.
In Singapore, where 8,575 cases have been reported, five people have died.
The region's health authorities had earlier warned that the hot weather brought on by the El Nino phenomenon may worsen dengue outbreaks by accelerating the breeding of Aedes mosquitoes.
Within medical communities, there are debates about a vaccine's efficacy, which varies according to the strains of dengue virus contracted. Data from trials shows an overall 65.6 per cent efficacy against the four strains of dengue.
Dr Tikki Pang, a visiting professor at the Lee Kuan Yew School of Public Policy, said the vaccine would benefit the region as a whole, and he urged Asean governments to consider pooling their purchases to negotiate for lower vaccine prices.
The region is home to 600 million people. The proportion of each dengue strain in a country can change over time, he said. "It's very hard to predict which will be the most prevalent serotype."
Nations like Malaysia and Singapore are still mulling over the potential use of the vaccine developed by French company Sanofi Pasteur.
To help spread awareness, the Asian Dengue Vaccination Advocacy has launched an online quiz and barometer on its website: http://denguemissionbuzz.org/