Pandemic Flu

Get the facts about Pandemic Flu

What is Pandemic Flu?

Pandemic Flu, also called Pandemic Influenza, occurs when a new influenza virus comes into the human population and little or no immunity exists to fight it. This could result in a global disease outbreak, which would have the potential to cause high levels of illness, death, social disruption and economic loss.

Influenza pandemics are naturally occurring. The 20th century saw three pandemics of influenza:

• The 1918 influenza pandemic caused at least 675,000 U.S. deaths and up to 50 million deaths worldwide.
• The 1957 influenza pandemic caused at least 70,000 U.S. deaths and 1 to 2 million deaths worldwide.
• The 1968 influenza pandemic caused about 34,000 U.S. deaths and 700,000 deaths worldwide.

It is not possible to predict when the next pandemic flu will occur, or how severe it will be. Wherever and whenever a pandemic starts, everyone around the world is at risk. Countries might take measures such as border closures and travel restrictions to delay arrival of the virus, but these efforts will not stop it.

Avian Influenza Viruses

Avian (bird) flu is caused by influenza A viruses that occur naturally among birds. There are different subtypes of these viruses because of changes in the virus’ proteins and the way the proteins combine. Each combination represents a different subtype. Wild birds are reservoirs for all known subtypes of influenza A virus, whereas in the human population, there are only four known A subtypes in circulation (H1N1, H1N2, H3N2, and H7N2). Historically, avian influenza viruses have acquired the ability to cause human disease. It is thought that all three pandemics of the 20th century had their origin in avian strains. Introduction of an avian influenza strain to the human population is a concern because humans have no immunity against these strains, which have the potential to result in higher rates of illness and death than the usual yearly influenza virus.

What is the current concern?

Health professionals around the world are concerned that the continued spread of highly pathogenic avian H5N1 influenza virus across eastern Asia and other countries represents a significant threat to human health. Since 2003, a growing number of human H5N1 cases have been reported in Asia, Europe, and Africa. Most of these cases have been caused by exposure to infected poultry; it does not appear that this virus has yet acquired the ability to be readily transmitted from person to person. Influenza A viruses are constantly changing, and some strains can adapt over time to infect and spread among humans. If the H5N1 virus were to gain the capacity to spread easily from person to person, a pandemic could begin. This is especially concerning because H5N1 appears to be highly virulent, resulting in death of more than 50 perent of those who have been affected. To date, there have been no cases of H5N1 in North America, in birds or humans.

No one can predict when a pandemic might occur. However, experts from around the world are watching the H5N1 situation very closely and preparing for the possibility that the virus may begin to spread more easily and widely from person to person.

Will vaccination and drug treatment be available for Pandemic Flu?

H5N1 or another avian influenza strain needs to undergo genetic changes in order to develop into a strain capable of producing a pandemic. A vaccine specific to the pandemic strain cannot be produced until this virus emerges and is identified. Using current vaccine technology, it is likely that there will be a six month period needed to develop this vaccine.

Studies done in laboratories suggest that some of the prescription medicines approved in the United States for human influenza viruses should work in treating avian influenza infection in humans. However, influenza viruses can become resistant to these drugs, so these medications may not always work. Additionally, in a pandemic scenario with high rates of illness in the general population, it is likely that these medications will be in short supply.

What is the government doing to prepare for Pandemic Flu?

The United States has been working closely with other countries and the World Health Organization (WHO) to strengthen systems to detect outbreaks of influenza that might cause a pandemic. Research is underway to effect the most expeditious development of vaccine and drug treatment, and determination of allocation of these important resources. In addition, Health and Human Services and other federal agencies are providing funding, advice, and other support to assist with pandemic planning and preparation. The federal government in conjunction with the Centers for Disease and Control (CDC) is providing up to date information and guidance through a website developed to pandemic influenza preparedness: www.pandemicflu.gov .

What can I do to prepare for an influenza pandemic?

The government has provided valuable “checklists” to enable individuals, families, businesses and other organizations to prepare for a pandemic. These are available at www.pandemicflu.gov/plan/checklists.html 

Because it is unlikely that vaccine and drug therapy will be available at the onset of a pandemic, it is important to learn what steps can be taken by an individual to minimize the spread of influenza. The habits of “respiratory hygiene” and “cough etiquette” can be protective from other respiratory illness, and beneficial to incorporate into your every day habits now. These include simple practices such as hand washing, covering your cough, and staying home when you are ill. More information on these practices can be found at  http://www.health.state.ny.us/publications/7102/