Think you know all there is to know about pandemic flu? Pandemic flu continues to be a popular and important media topic, yet there are several common misunderstandings that persist. The following are three issues you should understand so you and your patients can prepare for pandemic flu.

1. Pandemic flu is not the same thing as bird flu.

The urgency to prepare for a presumed imminent pandemic kicked into high gear with the spread of a strain of highly pathogenic bird flu (avian influenza A H5N1) throughout Asia starting in the late 1990s.

However, the media storm that followed the initial outbreak and spread of H5N1 caused a confusion in terms that lingers today. Bird flu is not the same thing as pandemic flu. The terms are not synonymous. The two terms should not be used interchangeably since this incorrectly implies that only this particular strain of bird flu might be responsible for the next pandemic, and it incorrectly implies that only bird flu viruses can cause a pandemic (pig viruses can also infect humans and may also be the cause of a flu pandemic).

Birds, like many other animals, can contract flu. Occasionally when people have contact with infected birds, they can acquire that virus. But bird flu does not spread from person to person, and the current strain of bird flu that has caused concern (H5N1) is not present in animals in the United States.

It is important to understand that an influenza pandemic occurs when a human flu virus mutates so dramatically--often when it jumps from one species to another--that there is no existing immunity in the population, so the newly mutated flu strain is able to spread rapidly from person to person.

2. Antivirals will not be effective for communitywide prevention during an influenza pandemic. Instead, teach patients to reduce exposure to flu.

While antivirals have been a valuable asset in the arsenal of medical advances against flu, their role in prevention of infection during a pandemic is greatly misunderstood.

For seasonal flu, antivirals have never been recommended as a substitute for vaccination. Vaccination is still the best method to keep from getting seasonal flu. But more importantly, to be effective as prophylaxis, antivirals must be taken for the entire length of exposure. For seasonal flu, this is typically based on expected household exposure, approximately a week. But pandemics can last for months, so many questions arise. When would you start taking antivirals? When would you stop? How would you obtain enough during a time when supplies would most likely be limited? What would be the side effects of taking an antiviral for a duration much longer than its approved use?

While the role of antivirals during a pandemic continues to be debated, most experts agree that the best response is not a medical solution to prevention, but a behavioral solution: avoiding situations that increase exposure and enacting healthy habits like washing hands, appropriately covering coughs and sneezes, and staying home when sick.

3. An influenza pandemic is not necessarily more severe than seasonal flu.

Preparing now against seasonal flu is not only important for staying healthy this season, but it can also help us prepare for pandemic flu, too. Yes, the impact of a pandemic can be substantial, but an influenza pandemic will not necessarily result in more illness and deaths than what we experience every year from seasonal flu. In fact, the last pandemic, the 1968 "Hong Kong Flu" (a strain of influenza A H3N2), is believed to have caused 34,000 deaths in the U.S. In contrast, seasonal flu is responsible for thousands of hospitalizations and an average of 36,000 deaths a year.

Each flu season is an opportunity for the medical community to minimize the effects of influenza by preparing itself for the possibility of a major flu outbreak or pandemic and by educating patients on flu prevention and home care.

Again, the most effective method to prevent contracting the flu is vaccination. This year, flu vaccine will be available in unprecedented levels. There is no longer a need to prioritize or limit vaccination. All people who wish to decrease their risk of illness should receive an influenza vaccination. By broadening the scope of people you vaccinate, you help reduce the burden of disease in our communities. Please encourage vaccination for all patients who do not have contraindications. Contraindications for influenza vaccination include severe allergic hypersensitivity to egg protein or other vaccine components and/or past medical history of Guillain-Barre. For further information on influenza vaccination, visit www.cdc.gov/flu/protect/keyfacts.htm.

To subscribe to free e-mail updates about seasonal and pandemic flu from the Los Angeles County Department of Public Health, e-mail fluwatch@listserv.ladhs.org.

Sadina Reynaldo, PhD, is the assistant program director for the Pandemic Influenza Unit of LA County Public Health's Emergency Response and Preparedness Unit.