Dengue — an emerging threat to global health

A mother comforts her son, who is suffering from dengue fever.Photo: AP

The incidence of Dengue fever, a mosquito-transmitted viral illness has grown dramatically around the world. Over 2.5 billion people — more than 40 percent of the world's population — are now at risk of Dengue. World Health Organisation's (WHO) South-East Asia region that includes Bangladesh and the Western Pacific regions are the most seriously affected. The disease is now endemic in more than 100 countries. An estimated 500000 people with severe dengue require hospitalisation each year, a large proportion of whom are children. About 2.5 percent of those affected die.
The Dengue virus is transmitted to humans through the bites of infected female Aedes aegypti mosquitoes that lives in urban habitats and breeds mostly in man-made containers.
The infection causes flu-like illness, and occasionally develops into a potentially lethal complication called severe Dengue. Dengue should be suspected when a high fever (104°F) is accompanied by two of the following symptoms: severe headache, pain behind the eyes, muscle and joint pains, nausea, vomiting, swollen glands or rash. Symptoms usually last for 2–7 days and then resolve spontaneously in most cases.
Severe Dengue characterised by severe bleeding is a potentially deadly complication due to blood loss, fluid accumulation in the chest, abdomen, breathing difficulty, organ impairment. Warning signs occur 3–7 days after the first symptoms in conjunction with a decrease in temperature (below 38°C/100°F) and include: severe abdominal pain, persistent vomiting, rapid breathing, bleeding gums, fatigue, restlessness, blood in vomit. The next 24–48 hours of the critical stage can be lethal; proper medical care is needed to avoid complications and risk of death.
To diagnose Dengue, laboratory investigations like platelet count or anti dengue antibody are recommended after 5 to 6 days.
There is no specific but symptomatic treatment is provided for dengue fever. Maintenance of the patient's body fluid volume is critical to severe dengue care.
At present, the only method of controlling or preventing dengue virus transmission is to combat the vector mosquitoes. Vaccines to immunise against dengue are underway but currently unavailable. Destroy the breeding place of Aedes mosquito — clean storage water like earthenware jars, metal drums, concrete cisterns, discarded plastic food containers, used automobile tyres and other items that collect rainwater.
Experts urged to improve community participation and mobilsation for sustained vector control and apply insecticides as space spraying during outbreaks as one of the emergency vector control measures.

Source: World Health Organisation