Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Small seasonal changes can lead to big flu outbreaks

16.11.2004


McMaster researcher investigates why influenza epidemics happen in the winter



Flu season is on its way to homes across Canada. But the question of why influenza epidemics take place in the few cold months of winter remains unanswered. Is it the change in the weather? The return to school? Or increased viral production under winter conditions?

The answer to the increase of flu cases may be extremely minute seasonal changes, says David Earn of the Department of Mathematics & Statistics at McMaster University. Earn, who uses mathematical models to investigate and understand how infectious diseases move through populations, recently examined the question of why most people catch the flu in the winter.


“In this study, we found that it may be difficult or even impossible to pin down the cause of seasonality in influenza epidemics,” Earn explains. “Large fluctuations in the number of flu cases between winter and other seasons may be caused by very small changes in the number of people infected by a single infectious person. These small changes in ‘transmission rate’ are amplified by interactions between the evolving virus and the changing level of immunity that people have to specific strains.”

Because the influenza virus is constantly adapting, immunity to the flu is not a permanent condition as it is with other viral diseases like chicken pox. Incorporating loss of immunity into a simple model of disease spread, Earn and colleagues at Princeton University and Harvard University found that under many scenarios, small seasonal changes in transmission rates can lead to regular, annual epidemics. Their work appeared in today’s edition of the Proceedings of the National Academy of Sciences of the USA.

Concludes Earn, “The reason that more people catch the flu in the winter appears to be that small seasonal changes in flu transmission at the individual level are greatly amplified as the disease spreads through communities. The underlying cause of seasonal fluctuations in transmission may be too small to measure.”

McMaster University, named Canada’s Research University of the Year by Research InfoSource, has world-renowned faculty and state-of-the-art research facilities. McMaster’s culture of innovation fosters a commitment to discovery and learning in teaching, research and scholarship. Based in Hamilton, the University has a student population of more than 20,000 and more than 112,000 alumni in 128 countries.

Julia Thomson | EurekAlert!
Further information:
http://www.mcmaster.ca

More articles from Health and Medicine:

nachricht Cholesterol-lowering drugs may fight infectious disease
22.08.2017 | Duke University

nachricht Once invincible superbug squashed by 'superteam' of antibiotics
22.08.2017 | University at Buffalo

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

Cholesterol-lowering drugs may fight infectious disease

22.08.2017 | Health and Medicine

Meter-sized single-crystal graphene growth becomes possible

22.08.2017 | Materials Sciences

Repairing damaged hearts with self-healing heart cells

22.08.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>