Record dengue epidemic looms
Change in climate helping mosquitoes that carry the disease thrive
- Published: 27/07/2013 at 11:14 PM
- Online news:
Thailand could face one of the largest dengue fever epidemics yet with the Public Health Ministry anticipating that over 120,000 people could contract the virus this year.
That would surpass the number of infections during the major outbreak in 2010.
SPRAY AND KILL: Kill the mosquitoes, cut down the dengue cases - that is the theory, as a public health worker sprays insecticide to kill mosquitoes in the Huai Kwang area of Bangkok earlier this month. (Photo by Thanarak Khoonton)
Last winter's warm temperatures and sporadic rainfall were obvious signs that a major dengue outbreak was due this year, health officials say.
More than 28,000 cases of dengue fever were reported between October to December last year even though winter is not the peak season for the disease.
The number of dengue cases continued to rise from January, with nearly 82,000 reported infections and 78 fatalities as of Friday, public health permanent-secretary Narong Sahamethapat said. Most of the fatalities were aged between 15-24 years.
The figure is three times higher than the same period last year, said Dr Narong, who heads the ministry's anti-dengue efforts.
Two major dengue outbreaks have been recorded in Thailand, with more than 170,000 cases reported in 1986, and 118,700 people infected in 2010.
The dengue prevention operation is at its most intense during the rainy season - from this month to September - when mosquitoes breed rapidly.
"But this disease cannot be controlled just through the work of the ministry," Bureau of Epidemiology director Pasakorn Akarasewi said. "It needs a chain of actions."
Dr Pasakorn said the disease control programme needs to work with other agencies and with local communities.
At the start of this year, the cabinet ordered various ministries, such as the Education and the Interior ministries, to work on a vector control and surveillance programme, which aims to terminate the breeding grounds for dengue-carrying mosquitoes.
Hospitals nationwide are also on alert.
So-called "dengue corners" have been set up at hospitals to screen patients with dengue-like symptoms to make a fast and efficient diagnosis.
"But the level of disease control efficiency is different in each area," Dr Pasakorn said.
According to public health reports, dengue fever is now spreading intensely in the border provinces in the North, including Chiang Mai, Chiang Rai and Mae Hong Son.
A number of cases are also being found in northeastern provinces such as Phetchabun and Loei.
Most cases are reported in remote communities which are difficult to reach, such as those in mountainous areas where disease prevention knowledge is poor and the vector control and surveillance programme is absent.
Some of these areas are inhabited by minorities and low-income communities unable to afford mosquito repellent.
The key activity in the dengue prevention programme is vector control, authorities say. Weak vector control at community levels allows Aedes mosquitoes, the carriers of dengue fever, to reproduce rapidly.
Society of Strengthening Epidemiology president Rungrueng Kitphati said changes in the climate might have helped the Aedes mosquitoes in "growing stronger and living longer".
Many Southeast Asian countries, including Thailand, are experiencing warmer temperatures and irregular rainfall, and such conditions benefit the dengue-carrying mosquitoes, he said.
Scientists have found that the Aedes mosquitoe's life span has increased from one to two months.
Normally, the mosquitoes feed in the day, but Thailand's warmer climate allows them to feed at night too, Dr Rungrueng said. He suspects the changing climate has played a part in the changes in the mosquitoes' life cycle and behaviour.
Urbanisation and poor waste management in cities are also to be blamed.
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Writer: Paritta Wangkiat