Local climate influences dengue transmission

February 17, 2009

Researchers from the US Centers for Disease Control and Prevention (CDC) and the Johns Hopkins Bloomberg School of Public Health have found that dengue transmission in Puerto Rico is dependent upon local climate and short-term changes in temperature and precipitation. Details are published February 17 in the open-access journal PLoS Neglected Tropical Diseases.

"Previous studies have shown that there are biological relationships between temperature, precipitation and dengue transmission, but empirical evidence of these relationships is inconsistent," says Michael Johansson, a postdoctoral fellow with the CDC's National Center for Zoonotic, Vector-Borne and Enteric Diseases Dengue Branch in San Juan, Puerto Rico.

"This finding on how local climate moderates the relationship between temperature, precipitation and dengue incidence helps explain previous discrepancies," he says. "It also suggests that the effects of global climate change on dengue transmission will be local rather than global."

The study looked at 20 years of data from 77 municipalities in Puerto Rico to demonstrate how local climate alters the patterns of disease transmission. The researchers found that even in a relatively small geographical area there were differences in the relationship between weather and dengue transmission.

For example, in the southwestern coast, where it is hot and dry, precipitation played a very strong role and temperature a lesser role in dengue transmission. In these dry areas, the lack of water limits mosquito reproduction. In contrast, in the cooler central mountains, temperature is more important and precipitation less important because the lower temperatures there slow mosquito and virus development.

Dengue is a disease caused by any one of four closely related viruses (DENV-1, DENV-2, DENV-3, or DENV-4). The viruses are transmitted to humans by the bite of an infected mosquito. The dengue viruses are the most widely distributed and damaging arthropod-borne viruses (arboviruses) affecting humans. The viruses and their predominant mosquito vector, Aedes aegypti, are endemic to most of the tropical and subtropical regions of the world, where they cause seasonal epidemics varying in size. In Puerto Rico, thousands of dengue cases and several dengue-related deaths are reported every year.

Citation: Johansson MA, Dominici F, Glass GE (2009) Local and Global Effects of Climate on Dengue Transmission in Puerto Rico. PLoS Negl Trop Dis 3(2): e382. doi:10.1371/journal.pntd.0000382, dx.plos.org/10.1371/journal.pntd.0000382

Source: Public Library of Science

Explore further: Climate variability and dengue incidence

Related Stories

Climate variability and dengue incidence

November 16, 2009

Research published this week in PLoS Medicine demonstrates associations between local rainfall and temperature and cases of dengue fever, which affects an estimated fifty million people per year worldwide. But the study finds ...

'Airport malaria' -- cause for concern in the US

November 11, 2008

In a global world, significant factors affect the spread of infectious diseases, including international trade, air travel and globalized food production. "Airport malaria" is a term coined by researchers to explain the more ...

Recommended for you

How the finch changes its tune

August 3, 2015

Like top musicians, songbirds train from a young age to weed out errors and trim variability from their songs, ultimately becoming consistent and reliable performers. But as with human musicians, even the best are not machines. ...

Machine Translates Thoughts into Speech in Real Time

December 21, 2009

(PhysOrg.com) -- By implanting an electrode into the brain of a person with locked-in syndrome, scientists have demonstrated how to wirelessly transmit neural signals to a speech synthesizer. The "thought-to-speech" process ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.