GUWAHATI, Sept 24 - Dengue viruses are not new to Assam or to other NorthEastern states. All the dengue virus serotypes were introduced to the region about one decade back, maintain sources in the Dibrugarh-based Regional Medical Research Centre (RMRC) of the Indian Council of Medical Research (ICMR).
The 1993, 1996, 1999, 2004 and 2006 RMRC entomological studies clearly speak of the presence of dengue vectors, namely-- Aedes aegypti and Aedes albopictus in all the NE states irrespective of their demography.
All the four dengue virus serotypes (DEN 1, 2, 3 and 4) are active in the NE region. RMRC documented serological evidence of dengue virus serotypes 2 and 4 in Assam and Nagaland in 1993.
Dengue-related death was reported from Manipur and Nagaland respectively in 2007 and 2009. But, Assam is yet to report any dengue-related death.
RMRC recorded dengue positive cases in the districts of Dhemaji, Dibrugarh, Darrang, Jorhat, Kokrajhar, Lakhimpur, Sonitpur, Sivasagar and Tinsukia between 2007 and 2009.
Hemorrhagic manifestation of the disease, in association with DEN-4, was also observed in Nagaland in 1996. Among all dengue virus serotypes, DEN-2 and 3 are more often associated with the severe and fatal hemorrhagic disease. However, till date no hemorrhagic case or its shock-syndrome-associated-outbreak is reported from Assam.
Dengue virus-carrying mosquitoes are daytime biters, usually biting during dusk and dawn hours. They may bite throughout the day, especially indoors, in shady areas, or during the cloudy weather.
Dengue leads to an acute fever. It can be life threatening and is caused by four closely related virus serotypes (Serotypes 1, 2, 3 and 4) of the species Flavivirus of the Flaviviridae family. It is also occurs widely in the tropical region.