Bangkok (The Nation/ANN) - The Public Health Ministry of Thailand has warned of a dengue-fever outbreak after reports that 20,000 people have been stricken during the past six months, 13 of them fatally.
Elderly people and children aged under one year are most at risk of dengue-fever infection, the ministry's permanent secretary Dr Paijit Warachit warned.
"People who have a high fever, fatigue or stomach-ache, or vomit or cannot eat, should seek treatment," Paijit said.
The continuing seasonal rainfall this year has increased the number of mosquitoes carrying the virus that causes dengue haemorrhagic fever.
Children below one year and elderly sufferers from chronic ailments - such as diabetes and high blood pressure - may develop severe symptoms after infection but are often unable to tell others of their illness.
According to Public Health Ministry records, from January to June, 23,324 people were infected with the dengue virus. Of this number, 13 succumbed to the disease.
The record also showed that 52 per cent of the total number of dengue cases were aged between 10 and 24 years. About 650 cases were children aged under one year, and 190 cases were aged over 65.
Aedes aegypti, a common species of mosquito, is the leading cause of this disease.
"We found that more than 80 per cent of mortality from dengue fever during July and August, the peak season for the disease, was caused by this common household mosquito," Paijit said.
Clinical Professor Siripen Kalayanarooj of the Queen Sirikit National Institute of Child Health said the number of dengue infections had drastically increased among babies and the elderly in recent years.
"The dengue fever virus strikes children easily, as they have a low level of immunity against it," she said, even though they get some immunity from their mothers.
She said severe symptoms and mortality from dengue fever among elderly people, especially those who have congenital disease, were usually the result of a secondary infection.
She suggested that people who develop high fever for more than two days should undergo immediate diagnosis and treatment at hospital.
Aspirin and ibuprofen are not recommended to reduce fever or to treat the illness, as these two drugs could cause bleeding in the stomach, leading to death.