It is just not the four known viruses that cause dengue - another one has been recently found in Malaysia. This will only add to the woes of vaccine makers and need more preventive measures.
Dengue is transmitted by the bite of a mosquito infected with one of the four dengue virus serotypes. It is a febrile (characterised by fever) illness that affects infants, young children and adults with symptoms appearing 3-14 days after the infective bite.
Scientists announced the discovery of the first new dengue serotype in the last 50 years at the third international conference on ‘Dengue and Dengue Haemorrhagic Fever’ held in Bangkok in October.
For vaccine developers, who have struggled to make a preparation effective against the four known serotypes, factoring in a fifth may be a major headache.
“We discovered and characterised a new dengue serotype,” said Nikos Vasilakis, a virologist at University of Texas Medical Branch in Galveston.
When contacted, Vasilakis told Express, “We found the virus in east Malaysian state of Sarawak. There is no evidence of its presence in countries like India, but given that the vector (aedes niveus s l) and the vertebrate hosts (NHPs) are there, it is quite possible that a yet undetected sylvatic transmission cycle may be present.”
“The strategy to combat dengue and its aftermath could only be an effective and sustainable vector control programme,” he added.