Straits Times 30 Mar 13;
DENGUE fever outbreaks are on the rise again in various parts of Asia, claiming victims in remote villages of India as well as tourist spots such as Bali.
In Indonesia, several regions have seen a spike in dengue cases. In East Java province, with 41 million people, there were 4,997 cases in January and February, three times the figure in the same period last year, local reports said. The number of deaths rose to 49, from 32 in the same period.
All four strains of the disease are present in Indonesia. Regions with higher incidence of dengue include Padang in West Sumatra, Central Kalimantan and Bali.
Australian media reported this month that 415 cases - or 80 per cent of all dengue cases in West Australia last year - could be traced to Indonesia, mostly in Bali.
The peak season of transmission in Indonesia is from January to May, as the rainy season gives way to warmer weather - a combination that fosters the spread of the mosquito-borne disease. Widespread puddles of stagnant water form perfect incubators for the Aedes mosquito.
Over in Thailand, experts warn that the country could be headed for a record year for dengue fever infections. As of March 11, there were 13,200 cases, a nearly fourfold increase compared to the same period last year.
Dr Monir Islam, acting World Health Organisation (WHO) representative to Thailand, said the rising figures are worrying because they are happening even before the start of the rainy season.
Thailand's Ministry of Public Health and the Bangkok Metropolitan Administration have issued public warnings. The ministry has stocked up on medical supplies and trained more clinicians to spot symptoms, said Dr Islam.
As to the reasons for the surge in infections, he suggested several. "It could be because water is collecting in more places like tyres or coconut husks, or it could be that the surveillance system has gotten better."
Another could be that people were becoming more complacent, and not protecting themselves when the Aedes mosquito strikes.
Dr A.P. Dash, regional adviser for vector-borne diseases at the WHO's South-east Asia regional office in New Delhi, said cases of hospitalisation from secondary infection are rising in India, Indonesia and Thailand. Population growth, urbanisation, and increased movement of people contribute to this surge.
India, with 1.2 billion people, will find it difficult to detect and contain the disease. WHO records show 17,744 cases with 117 deaths in 2011. Last year, the figures shot up to 49,602 cases and 241 deaths.
"The truth is India has a huge population and rudimentary disease recording so the whole shape and size and scope of the problem in India is poorly known," said United States-based tropical disease expert Scott Halstead, who focuses on dengue research. "There could be millions of cases."
Methods of containing the disease usually involve door-to-door checks and fogging. Malaysia, which stepped up such measures after a major outbreak in 2010, is confident of curtailing its spread.
As of March 23, there were some 5,700 cases, with Selangor and Johor registering the highest numbers. But the total number of cases has actually fallen compared to the 6,000 cases recorded over the same period last year.
Reporting by Zakir Hussain in Jakarta, Nirmala Ganapathy in New Delhi, Tan Hui Yee in Bangkok and Yong Yen Nie in Kuala Lumpur
