Researchers determine transmission requirements for dengue virus

Researchers from the Oxford University Clinical Research Unit announced on Tuesday that they have discovered the dose of dengue virus in human blood required to infect mosquitos.

Dengue is a viral infection that is transmitted between humans by mosquitos. Dengue causes flu-like symptoms in most people, but there is a small chance the case the disease can become life threatening. Studies show there could be as many as 390 million infections around the globe each year.

The research was able to find the level of dengue needed to transmit the disease from one person to another by mosquito bites. With this knowledge, researchers can now target experimental vaccines and drugs that could prevent the virus, which is currently only prevented by countermeasures targeting mosquitos.

"At the moment, dengue surveillance systems typically only count hospitalized patients but our findings confirm that less serious cases represent an equally important source of virus infection," Cameron Simmons, part of the clinical research unit at Oxford University, said. "Since these cases often remain in the community for the duration of their illness, it's important that we explore ways to prevent such patients from providing a source of further virus transmission."

The researchers found that mosquitos which feed on people who have a high level of dengue virus are more likely to be infectious to other humans two weeks later.

"Our findings suggest that focused public health intervention strategies to prevent transmission from these 'high risk' spreaders of the virus could have a major impact in slowing the spread of disease," Simmons said.