People help spread dengue fever5th February 2013
Current standard approaches to limiting the spread of dengue fever include targeting the virus' mosquito host around households already infected.
But researchers have found that concentrating prevention efforts in this area may be a waste of resources.
A study carried out by researchers from Peru and the United States has found that important transmission sites tend to spread dengue fever, rather than having infected mosquitoes near one's home.
A visit to such a place is enough to contract the disease, regardless of how well one's home has been treated with insecticide.
The team is urging public health policy makers to start looking at the role played by human movement in the spread of the disease.
Writing in the journal, Proceedings of the National Academy of Sciences, the researchers say they hope the findings will help control the deadly disease, which infects around 50 million people annually around the world.
Current techniques involve spraying insecticide within a 100-400 metre radius of infected households, because it is known that the Aedes aegypti mosquitoes that carry dengue do not travel further than this distance.
But the disease is more likely to be carried over greater distances than that by people, meaning that such campaigns are only partially effective, according to the study.
According to study lead author Steven Stoddard of the University of California, Davis, the technique should also be extended to include all houses that are part of the infected family's social network.
Stoddard and his team tracked people's movements and dengue transmission in two neighborhoods in Iquitos, Peru.
They found that when a person infected with dengue visited a house, the risk of infection and transmission rate went up substantially.
An infected person spread the disease to an average of three houses, two of which were outside the pesticide spraying area linked to their own house.
The researchers concluded that conventional control methods are missing important locations where dengue is transmitted, while resources were being wasted on locations where risk of transmission is low.
According to Ricardo Gürtler, an epidemiologist at the University of Buenos Aires, the study is unprecedented in its focus on human movement in mosquito-borne diseases.
He said it had opened up new perspectives on how social networks contribute to the spread of dengue, rather than the geographical distance of mosquitoes to people's houses.
He said cities where the virus is not yet endemic could use the findings to design policies aimed at controlling the influx of the virus carried by visitors from endemic areas.
Share this page
There are no comments for this article, be the first to comment!
Post your comment
Only registered users can comment. Fill in your e-mail address for quick registration.
Title: People help spread dengue fever
Author: Luisetta Mudie
Article Id: 23685
Date Added: 5th Feb 2013