Featured Research

from universities, journals, and other organizations

Paradoxical Relationship Discovered Between Dengue Hemorrhagic Fever And Its Carrier Mosquitoes

Date:
July 19, 2008
Source:
Public Library of Science
Summary:
Scientists have shown a negative correlation between dengue hemorrhagic fever and the density of the Aedes mosquitoes that transmit the virus. The study explains how current efforts to reduce the mosquitoes may actually increase the incidence of the potentially fatal viral disease.

A study by researchers in Thailand, Japan, and the UK has shown a negative correlation between dengue hemorrhagic fever (DHF) and the density of the Aedes mosquitoes that transmit the virus. The study explains how current efforts to reduce the mosquitoes may actually increase the incidence of the potentially fatal viral disease.

At least tens of millions of people are infected by dengue virus every year. Therefore, health authorities in tropical countries and the World Health Organization, have organized tremendous efforts towards the reduction of Aedes mosquitoes. However, the number of DHF patients continues to increase. To find an answer to this paradox, the researchers tested the hypothesis that more people with a mosquito-borne illness exist where there are more mosquitoes.

The researchers organized community volunteers who visited one million houses in Thailand and surveyed local densities of Aedes mosquitoes. They then compared this data to the number of people with DHF from each of 1,000 districts visited. The researchers found the incidence of DHF in areas of moderate mosquito density to be 40% higher than in areas of the highest mosquito density.

The researchers hypothesized that this paradoxical relationship is due to the peculiar fact that DHF develops most frequently when the patient is infected with dengue a second time. The results of this study imply that the current strategy of dengue control -- reducing Aedes mosquitoes -- may not necessarily be beneficial.

Additionally, the researchers developed computer simulation software based upon their hypothesis. The simulation predicted that epidemiological studies should be continued for a very long duration, preferably over a decade, to clearly detect such a paradoxical relationship between Aedes abundance and incidence of DHF. Such long-term studies are necessary, especially because tremendous efforts and resources have been (and perhaps will be) spent on combating Aedes.


Story Source:

The above story is based on materials provided by Public Library of Science. Note: Materials may be edited for content and length.


Journal Reference:

  1. Thammapalo et al. Relationship between Transmission Intensity and Incidence of Dengue Hemorrhagic Fever in Thailand. PLoS Neglected Tropical Diseases, 2008; 2 (7): e263 DOI: 10.1371/journal.pntd.0000263

Cite This Page:

Public Library of Science. "Paradoxical Relationship Discovered Between Dengue Hemorrhagic Fever And Its Carrier Mosquitoes." ScienceDaily. ScienceDaily, 19 July 2008. <www.sciencedaily.com/releases/2008/07/080715204849.htm>.
Public Library of Science. (2008, July 19). Paradoxical Relationship Discovered Between Dengue Hemorrhagic Fever And Its Carrier Mosquitoes. ScienceDaily. Retrieved September 16, 2014 from www.sciencedaily.com/releases/2008/07/080715204849.htm
Public Library of Science. "Paradoxical Relationship Discovered Between Dengue Hemorrhagic Fever And Its Carrier Mosquitoes." ScienceDaily. www.sciencedaily.com/releases/2008/07/080715204849.htm (accessed September 16, 2014).

Share This



More Plants & Animals News

Tuesday, September 16, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Some Tobacco Farmers Thrive Amid Challenges

Some Tobacco Farmers Thrive Amid Challenges

AP (Sep. 16, 2014) The South's tobacco country is surviving, and even thriving in some cases, as demand overseas keeps growers in the fields of one of America's oldest cash crops. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Scientists Given Rare Glimpse of 350-Kilo Colossal Squid

Scientists Given Rare Glimpse of 350-Kilo Colossal Squid

AFP (Sep. 16, 2014) Scientists say a female colossal squid weighing an estimated 350 kilograms (770 lbs) and thought to be only the second intact specimen ever found was carrying eggs when discovered in the Antarctic. Duration: 00:47 Video provided by AFP
Powered by NewsLook.com
Raw: Scientists Examine Colossal Squid

Raw: Scientists Examine Colossal Squid

AP (Sep. 16, 2014) Squid experts in New Zealand thawed and examined an unusual catch on Tuesday: a colossal squid. It was captured in Antarctica's remote Ross Sea in December last year and has been frozen for eight months. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Ivorians Abandon Monkey Pets in Fear Over Ebola Virus

Ivorians Abandon Monkey Pets in Fear Over Ebola Virus

AFP (Sep. 16, 2014) Since the arrival of Ebola in Ivory Coast, Ivorians have been abandoning their pets, particularly monkeys, in the fear that they may transmit the virus. Duration: 00:47 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

      Technology News



      Save/Print:
      Share:

      Free Subscriptions


      Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

      Get Social & Mobile


      Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

      Have Feedback?


      Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
      Mobile: iPhone Android Web
      Follow: Facebook Twitter Google+
      Subscribe: RSS Feeds Email Newsletters
      Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins