Scientists 'must not become complacent' when assessing pandemic threat from flu viruses

October 15, 2014

As our ability to assess the pandemic risk from strains of influenza virus increases with the latest scientific developments, we must not allow ourselves to become complacent that the most substantial threats have been identified, argue an international consortium of scientists.

Influenza pandemics arise when a new virus strain – against which humans have yet to develop widespread immunity – spreads in the human population. There have been five such pandemics in the past 100 years, the worst of which – the 1918 Spanish Flu – cost 50 million lives worldwide. Of these pandemics, three are thought to have spread from birds and one from pigs. However, influenza strains represent only a tiny fraction of the total diversity of that exist in nature; the threats posed by the majority of these viruses are poorly understood. Assessing which viruses pose the greatest risk of causing the next human pandemic is an enormous challenge.

Steven Riley from Imperial College London, an author of the study, says: "There are too many strains of influenza viruses out there in non-human hosts to make it feasible to make preparations against each one. Instead, we need to get better at assessing the pandemic risks so that we know where best to focus our efforts. At the moment, this assessment is largely driven by a simple idea: animal viruses that cause sporadic human infections pose a greater risk than viruses that have not been documented to infect humans. But in fact, none of the viruses that caused the major pandemics of the last century were detected in humans before they emerged in their pandemic form."

Writing in the journal eLife, the scientists set out the steps that they consider necessary to increase our ability to assess pandemic risk. As genome sequencing becomes cheaper, faster and more readily available, the data it generates has the potential to transform the research community's ability to predict the pandemic risk. However, it remains extremely difficult to predict just from a virus's genome what symptoms it will elicit in its host – and hence how deadly the virus is. The researchers call for better integration of experimental data, computational methods and mathematical models, in conjunction with refinements to surveillance methodology.

However, they say that scientific insights into non‐human influenza viruses must not give way to complacency that the most substantial threats have been identified and characterized. They point out that several recent strains including the 2009 H1N1 "swine flu" pandemic virus and the recently emerged H7N9 viruses in China highlight the importance of remaining vigilant against as-yet unrecognized high risk viruses and the value of surveillance for influenza viruses in humans.

"No one can say with anything close to a hundred percent certainty when or where the next pandemic will start or which virus will cause it," says Dr Colin Russell from the Department of Veterinary Medicine at the University of Cambridge. "We are getting much better at identifying and assessing potential threats, but we must be vigilant about surprises lurking around the corner.

"We need to be prepared for a swift response, with coordinated action, to help mitigate the spread of the next pandemic virus. Without developing this ability to respond, we will have spent billions building systems just for watching the next pandemic unfold."

Explore further: Reconstructed 1918 influenza virus has yielded key insights, scientists say

More information: eLife; 15 Oct 2015

Related Stories

Reconstructed 1918 influenza virus has yielded key insights, scientists say

September 11, 2012
The genetic sequencing and reconstruction of the 1918 influenza virus that killed 50 million people worldwide have advanced scientists' understanding of influenza biology and yielded important information on how to prevent ...

In-depth analysis of bat influenza viruses concludes they pose low risk to humans

October 2, 2014
Zoonosis—transmission of infections from other vertebrates to humans—causes regular and sometimes serious disease outbreaks. Bats are a well-known vertebrate reservoir of viruses like rabies and Ebola. Recent discovery ...

Insights into how a bird flu virus spreads could prevent pandemics

April 10, 2014
The H5N1 bird flu virus has infected and killed hundreds of people, despite the fact that, at the moment, the virus can't spread easily between people. The death toll could become much worse if the virus became airborne. ...

1950s pandemic influenza virus remains a health threat, particularly to those under 50

December 3, 2013
December 3, 2013) St. Jude Children's Research Hospital scientists have evidence that descendants of the H2N2 avian influenza A virus that killed millions worldwide in the 1950s still pose a threat to human health, particularly ...

Genes found in nature yield 1918-like virus with pandemic potential

June 11, 2014
An international team of researchers has shown that circulating avian influenza viruses contain all the genetic ingredients necessary to underpin the emergence of a virus similar to the deadly 1918 influenza virus.

Avian flu in seals could infect people

September 4, 2014
The avian flu virus that caused widespread harbor seal deaths in 2011 can easily spread to and infect other mammals and potentially humans.

Recommended for you

Anti-malaria drug shows promise as Zika virus treatment

November 17, 2017
A new collaborative study led by researchers at Sanford Burnham Prebys Medical Discovery Institute (SBP) and UC San Diego School of Medicine has found that a medication used to prevent and treat malaria may also be effective ...

Decrease in sunshine, increase in Rickets

November 17, 2017
A University of Toronto student and professor have teamed up to discover that Britain's increasing cloudiness during the summer could be an important reason for the mysterious increase in Rickets among British children over ...

Scientists identify biomarkers that indicate likelihood of survival in infected patients

November 17, 2017
Scientists have identified a set of biomarkers that indicate which patients infected with the Ebola virus are most at risk of dying from the disease.

Research team unlocks secrets of Ebola

November 16, 2017
In a comprehensive and complex molecular study of blood samples from Ebola patients in Sierra Leone, published today (Nov. 16, 2017) in Cell Host and Microbe, a scientific team led by the University of Wisconsin-Madison has ...

Study raises possibility of naturally acquired immunity against Zika virus

November 16, 2017
Birth defects in babies born infected with Zika virus remain a major health concern. Now, scientists suggest the possibility that some women in high-risk Zika regions may already be protected and not know it.

A structural clue to attacking malaria's 'Achilles heel'

November 16, 2017
Researchers from The Scripps Research Institute (TSRI) and PATH's Malaria Vaccine Initiative (MVI) have shed light on how the human immune system recognizes the malaria parasite though investigation of antibodies generated ...

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.