Bird Flu (H5N1 Avian Influenza Virus)
Despite the spread of the current bird flu among birds, this influenza virus is not easily transmitted from birds to humans or from one person to another. In fact, a relatively small number of humans have been affected by bird flu, mostly individuals who have been exposed to sick birds in rural areas of Asia, the Middle East and Africa. These persons (with perhaps some rare exceptions) have gotten bird flu from birds, not other people.
The Palo Alto Medical Foundation's (PAMF) Infection Control Committee has prepared the following responses to frequently asked questions about bird flu to help keep PAMF patients informed on this unfolding story. In this document, the term "bird flu" refers to the H5N1 avian influenza virus that first appeared in 1996 in Asia and has caused illness in millions of birds in many countries.
For more information on the bird flu, visit the U.S. Centers for Disease Control and Prevention (CDC) Web site www.cdc.gov or the U.S. Department of Health and Human Services (HHS) Web site www.pandemicflu.gov.
Frequently Asked Questions
What is the chance of a person getting bird flu at this time?
Almost zero. There have been only 385 documented cases of bird flu in humans in the world to date (World Health Organization, June 19, 2008). Most of these individuals have had close contact with sick birds including chickens and ducks. None of the current H5N1 virus has been reported in the United States or in bordering countries. Also, to our knowledge, bird flu has not affected tourists or travelers.
Could bird flu cause a worldwide influenza pandemic?
Possibly, but as time goes by, this seems less likely. There have been only rare instances of possible human-to-human transmission. Studies to date have shown that the bird flu genes have not mutated in a way that would allow the virus to spread easily from one person to another. And judging from the small number of cases of bird-to-human transmission, it’s difficult for people to get bird flu even from birds.
If a bird flu outbreak were to occur, PAMF would join a community-wide response led by public health authorities. PAMF is prepared to participate in a pandemic response because of its experience with community health education, large-scale vaccination, and infection control during the SARS outbreak.
What is being done to prevent a bird flu pandemic?
The World Health Organization (WHO) and some countries currently affected by the bird flu are hoping to limit spread of bird flu through a combination of culling birds that are sick from or exposed to bird flu, vaccinating healthy birds, modifying commercial farming practices, educating people in rural areas, expanding surveillance and rapidly deploying antiviral drugs if a localized outbreak of bird flu were to occur among people. Measures like isolation and quarantine, which were helpful in stopping the SARS epidemic, might be used to contain a bird flu outbreak in people as well, at least in the early stages of a pandemic.
What preparations are being made to protect us if a bird flu pandemic does break out?
On a federal level, several measures are being taken. First, surveillance systems are being upgraded to detect and monitor flu activity in the United States and other countries. PAMF is one of many sentinel sites in this system. Flu surveillance has improved dramatically in recent years. If bird flu starts to spread among humans, we will know about it quickly.
Second, great resources are being devoted to the development of an effective H5N1 influenza vaccine. In fact, an H5N1 vaccine has already been developed. Though not perfect, this vaccine is a beginning and innovative techniques are being used to improve on it. Many believe that an effective vaccine would be the single best weapon in the fight against pandemic influenza.
Third, the antiviral drug Tamiflu has been stockpiled at a federal level for rapid deployment in the event of a bird flu outbreak in the United States. If necessary, this drug would be distributed under the direction of local public health authorities.
Finally, state and local public health authorities, as well as community health providers such as PAMF, are making their own pandemic plans with guidance from the federal government. Some provider organizations, including PAMF, have periodic tabletop exercises to test their pandemic plan. The federal government released its "National Strategy for Pandemic Influenza" on May 3, 2006, which contains guidelines on pandemic planning for local health providers and individuals as well. The United States has also established a pandemic flu Web site: www.pandemicflu.gov.
Are travelers at risk for the bird flu? Should they take Tamiflu with them?
Travelers are not at risk in the vast majority of cases. The U.S. Centers for Disease Control and Prevention (CDC) advises avoiding contact with live, raw or diseased poultry. This is especially true in countries where bird flu has been detected. Unless an individual will be exposed to poultry in affected areas (such as a scientist studying bird flu), there is no need to carry a supply of an antiviral drug like Tamiflu for the reasons listed below.
- The risk of getting bird flu for the average traveler is extremely low.
- A traveler might waste precious time taking Tamiflu for a fever caused by another illness such as malaria or pneumonia.
Should people ask their physicians for a Tamiflu prescription so they can stockpile it in their homes?
We recommend against this practice for the reasons listed below.
- Bird flu in humans is extremely rare at this time, and it has not been detected in the United States.
- So far, there have only been rare instances of human-to-human transmission of bird flu.
- Studies on the bird flu virus to date have shown no evidence that it is developing the ability to spread easily from person to person.
- Taking an antiviral drug for a fever could delay the diagnosis of another more common and potentially serious infectious disease.
- The indiscriminate use of Tamiflu might promote resistance to this drug in flu viruses.
- Tamiflu has been in short supply at times, and we may need it to treat seniors and other high-risk persons who get seasonal influenza.
- There is no clear evidence that Tamiflu would be effective against the bird flu in humans (though we hope it might be) ─ even in patients with seasonal flu it only shortens the course of illness by one and a half days.
- The government is already stockpiling Tamiflu with the intent of distributing it rationally to have the most benefit if the need arises.
- In the early phases of a pandemic, simple infection control measures including covering your mouth when you cough, washing your hands frequently and staying home when you are sick with a flu-like illness may play a far greater role. In the long run, an effective vaccine would be the best weapon against a bird flu pandemic.
