Back home   |   Bookmark   |   Start page   |   Site map    
Services
News
Channels
Home & Family
Leisure
Technology
Business
Science
Site Search
Free email




Researchers find surprising pattern of influenza spread in south america and tropics

TheAllINeed.com
(NC&T/NIH) In their paper, "Seasonality of Influenza in Brazil: A Traveling Wave from the Amazon to the Subtropics," to be published in the American Journal of Epidemiology, the researchers document the seasonal spread of influenza viruses and seasonal mortality patterns associated with influenza across Brazil. The interest in Brazil arises because the country covers a range of latitudes and crosses several regions, including tropical and sub-tropical climates.

"This study contributes to the understanding of the role of tropical regions in the global circulation of influenza. It has direct implications for public health by offering guidance for the timing of delivery and composition of influenza vaccines," said Dr. Mark Miller, a co-author and Associate Director for Research at FIC.

As epidemic months of influenza in Brazil are triggered earlier in the year in the equatorial regions, vaccine recommendations using formulations from the Northern Hemisphere could be more appropriate for some countries in the Southern Hemisphere near the equator. This point is becoming increasingly important as more tropical countries introduce and use substantial quantities of vaccine.

Brazilian investigators worked with colleagues at FIC and the National Institute of Allergy and Infectious Diseases (NIAID) in revealing the unexpected spatial transmission patterns in the annual seasonality of influenza across a large area of the South American continent.

Brazil is nearly the same size as the United States. However, most of Brazil's territory lies in the tropical belt. This aspect makes the study valuable since less is known about the circulation of influenza viruses at these latitudes and how epidemics bridge and annually alternate between both hemispheres following the winter seasons.

Given the range of latitude encompassed by Brazil which crosses the equatorial and the southern tropic lines and using sophisticated mathematical analytical tools, the researchers studied the mortality data of influenza and pneumonia from two decades, together with laboratory confirmed data from recent years.

Both sets of independent data sources converged to show that, surprisingly, in Brazil influenza epidemics do not spread from where the highest human population densities are found, but rather from the equator towards more populous regions of the Southeast and South of Brazil.

The study, supported by FIC, results from a collaboration among researchers in different parts of the world. Study authors are Wladimir J. Alonso (FIC), Cécile Viboud (FIC), Lone Simonsen (NIAID), Eduardo W. Hirano (Mechanical Engineering Department, Universidade Federal de Santa Catarina, Florianópolis, Brazil), Luciane Z. Daufenbach (Secretariat of Health Surveillance, Ministry of Health, Brasília, Brazil), and Mark A. Miller (FIC).

About the Author
©2006 All rights reserved

More articles
Origins of marine creatures
Influenza transmission patterns
Reorganize the brain
Happy digital characters
Robotic brace
Childhood obesity
Silences overactive neurons
Surgery without scars
Love not in stars
Vary in attractiveness
Natural polyester
Tai boosts immune system
Embryos reproductive potential
Genes smoking cessation
Brain's braking mechanism
Dieting doesn't work
Quit smoking diet
Computer mimics blink
Acute mountain sickness
Sheep genetic drift
Quotes
Anyone who has never made a mistake has never tried anything new.
Albert Einstein.

Anything that happens enough times to irritate you will happen at least once more.
Tom Parkins Continuum.

Anns my sister, said Andy raggedly.-John Foster

Another 7 days has gone by.
mused Tom weakly.


Writers
If you are a writer and want to see your article published at Theallineed.com, just click here to submit.

Info
Today...
In the news...
Myanmar: UN agency moves ahead with assessing how to help cyclone-impacted children
"Based on the meetings that I have been having with senior government officials here, I get the impression that they are committed to do the best that they can to address the consequences of the disaster,"
Do you think that Judge should be nominated for the United States Supreme Court?
Yes, the President picked him and the Senate should just confirm him
Yes, he will help put a stop to activist rulings
No, he will royally srcew up the country
No, silent nominations never turn out well
 
Things to ponder
Do blind Eskimos heave seeing-eye sled dogs?

Did you know...
Dalmatians are born without spots.

Quote of the day
It is always easier to believe than to deny. Our minds are naturally affirmative.
John Burroughs

Featured article
How to decorate your house - For almost no cost!
Everyone wants to have a home like those featured in Architectural Digest, but if you're like most, your finances will not allow for it. There are, however, several approaches to decorating and designing that you can take...

 
© 2002 - 2007 Lexur