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 little evidence that the El Niño-Southern Oscillation - the climate cycle that occurs every three to four years as a result of the warming of the oceans in the eastern Pacific - has a significant impact on the incidence of dengue in Mexico, Puerto Rico or Thailand.

Large outbreaks of dengue, a vector-borne viral disease spread by the Aedes aegypti mosquito, occur every few years in many tropical countries. Michael Johansson, of the in Puerto Rico, used a technique called "wavelet analysis" to probe relationships between the local climate, El Niño, and incidence of dengue in Mexico, Puerto Rico and Thailand — three countries where dengue is endemic. They were able to separate and compare seasonal and multiyear components of each. In all three countries temperature, , and dengue incidence varied strongly on an annual scale, showing association in the wavelet analysis.

On the multiyear scale however, the researchers found no association between El Niño and dengue incidence in Mexico, a statistically insignificant association in Thailand, and an association in Puerto Rico only significant for part of the study period. The authors warn that the Puerto Rico outcomes should be viewed with caution.

The authors acknowledge that El Niño could still play a role undetected by this research. But as Pejman Rohani of the University of Michigan - uninvolved in the research - states in a related Perspective, the absence of a predictable link between El Niño and dengue transmission "is an important piece of information for the development of early warning systems".

More information: Johansson MA, Cummings DAT, Glass GE (2009) Multiyear Climate Variability and Dengue— El Niño Southern Oscillation, Weather, and Dengue Incidence in Puerto Rico, Mexico, and Thailand: A Longitudinal Data Analysis. PLoS Med 6(11): e1000168. doi:10.1371/journal.pmed.1000168

Related PLoS Medicine Perspective: Rohani P (2009) The Link between doi:10.1371/journal.pmed.1000185thern Oscillation. PLoS Med 6(11): e1000185. doi:10.1371/journal.pmed.1000185

Source: Public Library of Science (news : web)

Related Stories

Recommended for you

Four simple tests could help GPs spot pneumonia and reduce unnecessary antibiotics

November 23, 2017
Testing for fever, high pulse rate, crackly breath sounds, and low oxygen levels could be key to helping GPs distinguish pneumonia from less serious infections, according to a large study published in the European Respiratory ...

New approach to tracking how deadly 'superbugs' travel could slow their spread

November 22, 2017
Killer bacteria - ones that have out-evolved our best antibiotics—may not go away anytime soon. But a new approach to tracking their spread could eventually give us a fighting chance to keep their death toll down.

Research points to diagnostic test for top cause of liver transplant in kids

November 22, 2017
Biliary atresia is the most common cause of liver transplants for children in the United States. Now researchers report in Science Translational Medicine finding a strong biomarker candidate that could be used for earlier ...

Metabolites altered in chronic kidney disease

November 22, 2017
Chronic kidney disease (CKD) affects 1 in 7 people in the United States, according to the U.S. National Institute of Diabetes & Digestive & Kidney Diseases (NIDDK). These individuals have a very high risk of cardiovascular ...

Alcohol consumption and metabolic factors act together to increase the risk of severe liver disease

November 22, 2017
A new study provides insights into the interaction between alcohol consumption and metabolic factors in predicting severe liver disease in the general population. The findings, which are published in Hepatology, indicate ...

Rainfall can indicate that mosquito-borne epidemics will occur weeks later

November 22, 2017
A new study demonstrates that outbreaks of mosquito-borne viruses Zika and Chikungunya generally occur about three weeks after heavy rainfall.Researchers also found that Chikungunya will predominate over Zika when both circulate ...

0 comments

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.