Navigation Links
Tracking the spread of dengue fever: Domestic networks drive rapid transmission of human infection
Date:1/24/2013

The mosquitoes that spread dengue fever tap into the domestic networks of humans, along with their bloodstreams, finds a study recently published in the Proceedings of the National Academy of Sciences (PNAS).

The data from Iquitos, Peru, shows that the trail of the most rapid transmission of human infections does not lead through large, public gathering places, as might be expected, but from house-to-house, as people visit nearby friends and relatives.

"It's common in a dengue fever outbreak to first treat public places like schools for mosquitoes, but our results show the focus needs to be on residential networks," says disease ecologist Gonzalo Vazquez-Prokopec.

Vazquez-Prokopec and Uriel Kitron, both from Emory University's department of environmental studies, conducted the spatial-temporal analysis as co-authors of the study, led by Steve Stoddard and Thomas Scott from the University of California, Davis. The research is part of a major, ongoing dengue project that also includes scientists from the U.S. Navy; the University of Iowa; Tulane University; San Diego State; and researchers in Peru.

"On a global scale, human air travel is known as a driver of dengue virus circulation, but this is the first time we've quantified the powerful impact of human movement on the small scale of neighborhoods," Vazquez-Prokopec says.

The tropical disease is caused by a virus that is passed from the blood of one person to another through the bites of mosquitoes. Also known as "break-bone fever," dengue causes debilitating pain leading to the hospitalization of many sufferers. Severe cases can be fatal.

"It is vicious, and rapidly growing as a threat," Vazquez-Prokopec says.

During the last 50 years, the incidence of dengue has increased 30-fold and more than half the world's population is now at risk. The World Health Organization estimates that 50-100 million dengue infections occur each year. That number is expected to rise as the climate warms and the trend toward urbanization continues.

During 2009 and 2010, dengue fever emerged for the first time in decades in the contiguous United States, when an outbreak in the Florida Keys led to 93 cases.

The dengue virus is complex and has at least four different serotypes. Each time a person is infected with one serotype, it raises the risk that they will become more severely ill if infected by a different serotype.

"There is no vaccine for dengue. The only way to control outbreaks is to kill the vectors mosquitoes," Vazquez-Prokopec says. Many of the places affected have poor public health infrastructure, he adds, so it's critical to identify the most effective places to spray for the insects.

A 2009 outbreak of dengue in Iquitos killed at least 24 people and drove almost 1,000 sufferers to the hospital, where cots had to be set up in stairwells and hallways to handle the flood of patients.

A city of 400,000 located deep in the Amazonian rain forest, Iquitos is essentially an island, only accessible by boat or plane. The city has high unemployment, and the housing is often substandard. Water is stored in open containers in crowded homes that lack air-conditioning, or even window screens. These factors make the homes havens for Aedes aegypti mosquitoes, the primary vector for the dengue virus. These mosquitoes feast almost exclusively on human blood, bite during the day, and have a limited flight range of about 100 meters.

To study how the dengue virus spreads through Iquitos, the researchers tracked and mapped outbreak patterns of two large neighborhoods, encompassing hundreds of homes, over several years. When a case of dengue was confirmed through a blood test, social workers would interview the patient, recording all the places the patient went during the 15 days leading up to the onset of fever. Mosquitos were collected from as many of these locations as possible and tested to determine if they carried the virus.

The data from interviews of 2,000 people was plotted over time and space using geographic information systems (GIS) technology.

"People appear to be getting infected most often in homes, but not necessarily their own homes," Vazquez-Prokopec says. "The main driver is people visiting friends and relatives in nearby homes."

Interviews with dengue patients revealed that two-thirds of them had visited the same location.

"We suspect that the importance of human movement that we observed in Iquitos will hold in other populations and for other pathogens transmitted by the mosquitos that spread dengue," Vazquez-Prokopec says. "The findings provide a different way for thinking about how a vector-borne pathogen may spread through a population, and have implications for better disease surveillance and control."


'/>"/>

Contact: Beverly Clark
beverly.clark@emory.edu
404-712-8780
Emory University
Source:Eurekalert

Related medicine news :

1. Tracking Love, Lust in the Brain
2. Tracking the wave of success for Team GBs swimmers
3. AFTS Labs Partners With Physicians To Complement NY's Mandated I-STOP Tracking System For Pain Pill Prescriptions: A Recipe For A Safer Community
4. Cell-Based Tracking Devices Might Help Monitor Treatments
5. Health Officials Tracking Salmonella Outbreak Linked to Pet Turtles
6. Tracking environmental causes of good and bad health
7. New tumor tracking technique may improve outcomes for lung cancer patients
8. Tracking down smallest biomarkers
9. Tracking the origins of HIV
10. New drug prevents spread of human prostate cancer cells
11. NIH scientists link quickly spreading gene to Asian MRSA epidemic
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/24/2017)... ... March 24, 2017 , ... “End Time GPS”: ... events will interrelate. “End Time GPS” is the creation of published author, Wesley ... while working on military munitions and space-vehicle projects. Now, at age ninety-one, he shares ...
(Date:3/23/2017)... Seattle, WA (PRWEB) , ... March 23, 2017 , ... ... emergency and now estimates that there could be four million Zika-related cases in the ... to date with numbers of US cases reported per year skyrocketing to an estimated ...
(Date:3/23/2017)... Braunfels, TX (PRWEB) , ... March 23, 2017 , ... ... new clinic, located at 960 Gruene Road in Building 2. The clinic is the ... Dr. Andrew Bennett, PT, says opening the company’s second New Braunfels location brings things ...
(Date:3/23/2017)... ... ... are unaware of the dangers that infectious bacteria play in mouth disease, while 1 out ... that dentists recommend. The ramifications of improper oral upkeep go far beyond bad breath and ... hours of work each year due to dental issues. That is why Mediaplanet is proud ...
(Date:3/23/2017)... ... March 23, 2017 , ... The StayWell Company announced today ... accreditation covers StayWell’s asthma, coronary artery disease, congestive heart failure, chronic obstructive pulmonary ... have excellent programs for the delivery and improvement of disease management and that ...
Breaking Medicine News(10 mins):
(Date:3/23/2017)... Research and Markets has announced the addition of the ... ... oxygen therapy devices market to grow at a CAGR of 10.16% ... Therapy Devices Market 2017-2021, has been prepared based on an in-depth ... market landscape and its growth prospects over the coming years. The ...
(Date:3/23/2017)... A research report by Mordor Intelligence ... reach USD 7.2 billion by the end of 2021 and ... procedure in which a sample is preserved prior to its ... since the methods are often allowing repeated testing. The report ... shared procedures in the lab. In many life science labs, ...
(Date:3/23/2017)... BOSTON , March 23, 2017 ... respond optimally to most vaccines because their young ... researchers at Boston Children,s Hospital report achieving strong ... the final preclinical model before human trials — ... the immune response. In two simultaneous papers, they ...
Breaking Medicine Technology: