During the early stages of a flu pandemic, vaccine that protects against the pandemic flu strain probably won't be available. Antibiotics, and medications that work against viruses (“antivirals”) will be in short supply.

Will there be a vaccine to prevent pandemic flu?

Scientists are working now to develop a vaccine for the H5N1 “bird flu” virus. However, the H5N1 virus may or may not end up causing a pandemic. If H5N1 does change enough to cause a pandemic, the H5N1 vaccine may no longer work. And a future pandemic could be caused by a completely different strain.

Flu vaccines have to be made specifically for a particular strain of the flu virus. That’s why the vaccine for “regular” flu has to be changed each year, because the virus also changes from year to year.

Flu vaccine also takes several months to produce. Once we have identified a pandemic strain, a matching vaccine will need to be developed. It will take at least six months to do the necessary research, grow the virus, make the vaccine and test it. Therefore, we are unlikely to have vaccine available during the first stages of a pandemic. It may be available later, when a second or third wave of flu cases would be expected.

What about antivirals?

Drugs that fight viruses – known as antivirals – may be helpful in treating pandemic flu, but their use has several limitations.

• To be effective, antivirals have to be given very quickly after symptoms first appear.
• It will not be possible to give everybody antiviral drugs and some will not need them.
• It is difficult to identify which groups of people will develop more serious illness and will need the antivirals most.
• We won't know how effective each type of antiviral will be until we know exactly which virus is causing the pandemic.
• The virus will probably be resistant to some or all antiviral medications, and may develop more resistance over time.

Should I buy my own supply of Tamiflu, or some other antiviral medication?

We are urging people not to do that, for a number of reasons.

• There aren’t enough antiviral drugs for everybody.
• Some people won’t need antivirals, and it is difficult to identify in advance those individuals who will need them most.
• To help ensure that antivirals are available for those most in need, public health workers and health care providers must be in a position to manage available supplies of these drugs. That won’t be possible if they are being stockpiled by private individuals.
• Indiscriminate use of antivirals may increase the possibility that the pandemic virus will become resistant to these drugs, potentially making them useless. Some strains of avian flu are already developing resistance to Tamiflu.
• Personal stockpiling may reduce available supplies of antivirals, making it harder to treat “regular” flu in the elderly, and others who face an immediate risk of serious illness and death from complications of the flu.
• The shelf life of Tamiflu is only five years, and no one knows how long it may be before a pandemic occurs.
• At $5 per pill, not everyone will be able to afford a personal stockpile.

How about antibiotics or the pneumococcal vaccine?

Antibiotics won’t help against a virus, but they may help if you get a secondary infection caused by bacteria. For most of the people who have died from H5N1 influenza, the virus was the cause of death. However, during the 1918 pandemic, may people died from pneumonia and other bacterial illnesses. There are also vaccines that protects against infections caused by some types of pneumococcal bacterial, which are a major cause of pneumonia.