The clinical and serological study titled 'Surveillance of Dengue Viral Disease in Bangladesh' aims at finding prevalence of dengue infection, age distribution of victims of dengue fever and dengue haemorrhagic fever and determining laboratory capacities to identify dengue infection and the serotypes involved in primary and secondary infection.

"The study will be used to plan future strategies to fight dengue infection. We are doing it to get the first hand information on the percentage of the population infected with dengue virus. Prevalence of the virus in rural areas will also be studied," said one of the investigators.

The study will also involve creating awareness, treatment of serious dengue patients and dissemination of information to policymakers and professionals.

The study will be conducted at Dhaka Shishu Hospital (DSH), National Medical College Hospital and at four thana health complexes in Rangmati, Pabna, Sunamganj and Jessore. It will be done from November to February in the dry season and from May to August in the wet season for two years.

Blood samples of 1,920 dengue patients of over six months of age will be collected for culture.

The studies will be conducted by experts from the International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B). The team will be led by Dr A K Siddique, a senior scientist heading the Epidemic Control and Preparedness Programme at ICDDR,B.

The magnitude of dengue infection in Bangladesh is still unknown. As per records, dengue virus existed in Dhaka city also in 1963 and 1983. A large number of dengue cases were reported in 2000.

There are four types of distinct but closely related viruses that cause dengue infection. These are called serotype - 1, 2, 3 and 4.

A joint study by ICDDRB and a leading hospital in Thailand last year found prevalence of dengue serotype-3 among the people of Dhaka city.

Globally, 100 million cases of dengue fever and over 250,000 of dengue haemorrhagic fever (DHF) with 25 per cent deaths are recorded in a year. Over two billion people are potentially at the risk of dengue infection.

In South-East Asian countries, more than 40,000 deaths from DHF were officially reported between 1956 and 1990.

Among others, Dr Mahbubur Rahman, Dr Abdulla H Bqui and Dr K A H M Akram of ICDDR, B, Dr Manzoor Hussain, Director of Dhaka Shishu Hospital and Dr Mahmudur Rahman, Director of National Medical College Hospital will be involved in the study.