BANGKOK – Thailand’s Department of Disease Control has announced a dengue hemorrhagic fever epidemic that has seen 28,785 patients suffering from dengue, 43 of whom died since the start of the year.
Dr Preecha Prempree, deputy director-general of the department, said that the figures were from Jan 1 to June 11, when the number of patients doubled the five-year average.
The situation is the same in Thailand’s neighboring countries thanks to a similar climate and conditions, he said. He attributed the epidemic to failure to control mosquito larvae.
On Friday, the Public Health Ministry signed an agreement with nine agencies to seriously control mosquito larvae. They are the Defence Ministry, Tourism and Sports Ministry, Ministry of Natural Resources and Environment, Interior Ministry, Culture Ministry, Education Ministry and Bangkok Metropolitan Administration .
Dr Sukhum Kanchanapimai, permanent secretary for public health, said the control would focus on communities, temples, schools and hospitals. “Communities and temples are major sources of mosquito larvae,” he said.
The most affected provinces include Trat bordering Cambodia and Samut Skhon Southeast of Bangkok. Dengue is endemic in Thailand and risk is present in both urban and rural areas, with elevated risk in northeastern part of the country. Peak transmission typically occurs during the rainy season, from April till December.
The World Health Organization estimates that 50-100 million people are infected by the dengue virus yearly.
In some cases, Dengue infection is asymptomatic – persons do not exhibit symptoms. Those with symptoms get ill between 4 to 7 days after the bite. The infection is characterized by flu-like symptoms which include a sudden high fever coming in separate waves, pain behind the eyes, muscle, joint, and bone pain, severe headache, and a skin rash with red spots. Treatment includes supportive care of symptoms. There is no antiviral treatment available.
The illness may progress to Dengue Hemorrhagic Fever (DHF). Symptoms include severe abdominal pain, vomiting, diarrhea, convulsions, bruising, and uncontrolled bleeding. High fever can last from 2 to 7 days. Complications can lead to circulatory system failure and shock, and can be fatal (also known as Dengue Shock Syndrome).
If you are infected with the same Dengue virus serotype you become immune to future infections. However, if you are infected subsequently with a different serotype, immunity wanes over time which increases the risk of developing Dengue Hemorrhagic Fever.
Travellers should take meticulous measures to prevent mosquito bites during the daytime.
- Use a repellent containing 20%-30% DEET or 20% Picaridin on exposed skin. Re-apply according to manufacturer’s directions.
- Wear neutral-coloured (beige, light grey) clothing. If possible, wear long-sleeved, breathable garments.
- If available, pre-soak or spray outer layer clothing and gear with permethrin.
- Get rid of water containers around dwellings and ensure that door and window screens work properly.
- Apply sunscreen first followed by the repellent (preferably 20 minutes later).
- More details on insect bite prevention.
A vaccine is available for people living in some Dengue endemic countries, but is not commercially available for travellers.