Malaysia: 'Mosquitoes born with dengue virus'

SIM BAK HENG New Straits Times 30 Jan 16;

KUALA TERENGGANU: Transovarial transmission of dengue virus is most likely to have triggered the dengue outbreak in Terengganu, said the Institute for Medical Research (IMR).

This is in view that the transovarial dengue virus was present in the country, according to a research carried out by IMR.

Although the number of mosquito larvae having dengue virus in the research was small (6.3 per cent), it was evident that transovarial transmission for dengue virus could be the cause.

IMR medical entomology unit research officer Dr Rohani Ahmad said Terengganu was one of the states where transovarial dengue virus was present.

“We have conducted dengue virus screening in Aedes mosquitoes in the state.

Our studies showed the presence of dengue virus in mosquito larvae. “This means that a mosquito is born with the virus naturally.

The state Health Department declared a dengue outbreak in the state on Jan 13.

Dengue claimed its sixth victim, a 33-year-old man from Dungun, on Thursday, while an 11-year-old pupil of SK Seri Budiman is in critical condition.

As transovarial dengue virus was transmitted through birth, Dr Rohani said, the danger was such that the vector could transmit dengue virus once it emerged from the immature stage, such as pupa.

“If more transovarial mosquitoes mature, more people will become victims. “The mosquito can trigger a transmission without having to sting any persons infected with the virus.

“Imagine an area with 1,000 mosquitoes carrying transovarial dengue virus.

The chances of getting bitten and infected are high and an outbreak is possible.”

Dr Rohani said plastic containers were the most conducive breeding sites, followed by aluminium containers and tyres.

The dominant mosquito larvae collected during the IMR study were Aedes albopictus and Aedes aegypti.