Health Experts Strategize to Avert Global Bird Flu Pandemic

WASHINGTON, DC, October 7, 2005 (ENS) - In response to a growing number of human deaths from bird flu and the fear of a global pandemic, the U.S. State Department is hosting a two day meeting of officials from more than 65 nations and international organizations concerned about preventing the spread of an influenza virus that has stricken birds in 11 nations.

Under Secretary of State Paula Dobriansky and Health and Human Services Secretary Michael Leavitt opened the International Partnership on Avian and Pandemic Influenza Senior Officials Meeting Thursday at the National Academy of Sciences building in Washington.

The meeting’s main objective is to affirm the commitment of participating countries to work together to fight avian influenza and jointly develop a plan of action to supplement international efforts.

State Department spokesman Sean McCormack said Wednesday the agency hopes all participating countries will support a set of 10 core principles that Dobriansky and Leavitt unveiled at the United Nations in September.

“At the heart of these core principles,” McCormack said, “are quick and accurate reporting of potential outbreaks, donor support for countries that have been or might be affected, and a pledge to work closely on the issue with the World Health Organization (WHO).

hen

Hen shows symptoms of avian influenza. Hundreds of millions of birds were killed across Asia since 2003 in an attempt to halt the disease. (Photo courtesy FAO)
The unprecedented outbreak of the H5N1 strain of avian influenza A in Asia poses a serious threat of causing the next global influenza pandemic, health experts fear. H5N1 viruses, to which humans have little or no immunity, have demonstrated the capacity to infect humans and cause severe illness and death.

These viruses have not yet demonstrated the capacity for efficient and sustained person-to-person transmission, although limited person-to-person transmission was the cause of at least one family cluster of cases in Thailand.

Last week UN Secretary-General Kofi Annan appointed British health expert Dr. David Nabarro as coordinator for the United Nations response to avian and human influenza.

Nabarro will be responsible for ensuring that the UN system makes an effective and coordinated contribution to the global effort to control the bird flu epidemic.

The World Health Organization has confirmed 116 human cases of bird flu and 63 deaths since the latest outbreak began in December 2003.

Four countries - Vietnam, Thailand, Cambodia and Indonesia - have reported human cases of the disease caused by the H5N1 virus strain.

An estimated 150 million birds have been culled or have died from the disease since December 2003.

Health officials fear the H5N1 virus will mutate and mix with human influenza, creating a deadly pandemic strain that becomes easily transmissible and could kill millions of people.

Alfonso Torres, director of the Animal Health Diagnostic Center and associate dean for veterinary public policy at Cornell University's College of Veterinary Medicine, said "The fear is that if the virus changes or recombines with a regular human flu, the virus may acquire the ability to be effectively transmitted from human to human, then it could become the big pandemic that everyone is very concerned about."

Influenza pandemics occur when a new strain emerges to which people have little or no immunity. As long as the disease stays primarily a bird flu, officials have some control, says Torres, a former U.S. chief veterinary officer and director of the Plum Island Animal Disease Center, a high-security animal laboratory previously operated by the U.S. Agriculture Department but now part of the Department of Homeland Security.

patient

Hospital workers tend a case of avian flu in Vietnam. (Photo credit unknown)
The 1918 Spanish flu was a global disaster, killing up to 50 million people. Now, U.S. scientists have found the 1918 virus was probably a strain that originated in birds. It shares genetic mutations with the bird flu virus now circulating in Asia, the researchers found.

Writing in the journal "Nature," they say their work underlines the threat the current strain poses to humans worldwide.

The work, done in collaboration with Mount Sinai School of Medicine, the Armed Forces Institute of Pathology and Southeast Poultry Research Laboratory, determined the set of genes in the 1918 virus that made it so harmful. Jeffery Taubenberger of the Armed Forces Institute of Pathology, is the lead author of the sequencing study.

In a separate paper in the journal "Science" Terrence Tumpey at the Centers for Disease Control and Prevention (CDC) in Atlanta, Georgia, and his co-workers have used Taubenberger's sequence to recreate the complete 1918 virus.

“By identifying the characteristics that made the 1918 influenza virus so harmful, we have information that will help us develop new vaccines and treatments,” said Dr. Tumpey, the CDC senior microbiologist who recreated the virus. “Influenza viruses are constantly evolving, and that means our science needs to evolve if we want to protect as many people as possible from pandemic influenza.”

The recreated virus is contained at CDC, following stringent safety conditions designed for flu viruses and heightened security elements mandated by the CDC's Select Agent program.

"We felt we had to recreate the virus and run these experiments to understand the biological properties that made the 1918 virus so exceptionally deadly,” Tumpey said.

“We wanted to identify the specific genes responsible for its virulence,” he added, “with the hope of designing anti-virals or other interventions that would work against virulent pandemic or epidemic influenza viruses."

More research is needed on anti-virals and vaccines for a future flu pandemic, but Tumpey noted encouraging signs.

The anti-viral drugs oseltamivir (Tamiflu®) and amantadine (Symmetrel®) have been shown to be effective against viruses carrying certain genes from the Spanish flu virus. And vaccines containing other Spanish flu genes were protective in mice.

At the University of Maryland, Steven Salzberg and co-authors reported in the journal "Nature" on Wednesday that they had performed the first large-scale sequencing of 209 complete genomes of influenza A.

It is a technique the authors think can reduce the guesswork of predicting which virus will emerge as the dominant starin in approaching flu seasons.

"This is the first-ever large-scale project to sequence the influenza virus," Salzberg said. "It is already giving us remarkable new insights into the rapid evolution of the flu as it moves through the human population."

The initial results are for the Influenza Genome Sequencing Project, a joint project of the National Institute of Allergy and Infectious Diseases, part of the National Institutes of Health, and several scientific partners, to help researchers understand how flu viruses evolve, spread and cause disease.

"The goal,” said Salzberg, “is to sequence thousands of influenza genomes, including avian influenza. By making the data public immediately, we can speed up the process of understanding how the virus is mutating all over the world."

Ten Core Principles for Dealing with a Global Avian Flu Pandemic

  1. International cooperation to protect the lives and health of our people

  2. Timely and sustained high-level global political leadership to combat avian and pandemic influenza

  3. Transparency in reporting of influenza cases in humans and in animals caused by strains that have pandemic potential, to increase understanding, preparedness and, especially to ensure rapid and timely response to potential outbreaks

  4. Immediate sharing of epidemiological data and samples with the World Health Organization (WHO) and the international community to detect and characterize the nature and evolution of any outbreaks as quickly as possible, by utilizing, where appropriate, existing networks and mechanisms

  5. Rapid reaction to address the first signs of accelerated transmission of H5N1 and other highly pathogenic influenza strains so that appropriate international and national resources can be brought to bear

  6. Prevent and contain an incipient epidemic through capacity building and in-country collaboration with international partners

  7. Work in a manner complementary to and supportive of expanded cooperation with and appropriate support of key multilateral organizations (WHO, Food and Agriculture Organization, World Organization for Animal Health)

  8. Timely coordination of bilateral and multilateral resource allocations, dedication of domestic resources (human and financial), improvements in public awareness, and development of economic and trade contingency plans

  9. Increased coordination and harmonization of preparedness, prevention, response and containment activities among nations, complementing domestic and regional preparedness initiatives and encouraging where appropriate the development of strategic regional initiatives

  10. Actions based on the best available science