Pandemic Flu Facts
What is pandemic influenza? How is it different from ordinary flu? How likely is an influenza pandemic? What would it be like in Minnesota?
On this page:
What is pandemic flu?
How does a flu pandemic start?
What is the difference between pandemic flu and seasonal flu?
How likely is a flu pandemic?
Will I catch pandemic flu?
What was the 1918 pandemic like in Minnesota?
What would the next pandemic be like in Minnesota?
Will schools close?
Will there be a vaccine for the pandemic flu?
What can I do now?
More information about pandemics
Download PDF version formatted for print: Pandemic Flu Facts (PDF: 48KB/3 pages)
A pandemic occurs when a disease spreads rapidly, affecting most countries and regions of the world. Influenza pandemics have occurred periodically throughout human history – including a major pandemic in 1918, and smaller pandemics in 1957 and 1968. The symptoms of pandemic influenza are similar to those of ordinary flu but are usually more severe.
Flu viruses are constantly changing, producing new strains. Influenza pandemics occur when a virus emerges that is so different from previously strains that few, if any, people have any immunity to it. This allows it to spread widely and rapidly, potentially affecting millions of people worldwide. The new virus may be the result of an animal virus, usually from a bird, mixing with a human virus to produce a new strain.
- Occurs every year during the winter
- Affects up to about 10% of the population
- For most people it is an unpleasant but not life-threatening infection
- The very young, the very old, and people with certain chronic illnesses are most at risk of serious illness
- Annual vaccination is available
- Antiviral drugs are available to treat those at special risk
- Has occurred three times in the last 90 years
- Can occur at any time of the year
- It is a more serious infection for everyone
- People of every age may be at risk of serious illness
- A vaccine probably won’t be available when the pandemic starts – when it does become available the aim will be to immunize people as rapidly as possible as vaccine supplies become available
- Antiviral drugs are likely to be in limited supply and will have to be used to best effect according to how the disease develops
Vaccine against ordinary flu will not protect against pandemic flu. However, getting your annual flu shot is one of several things you can do to keep yourself healthy, and that may help you fight off the pandemic virus.
Three pandemics have occurred in the last 90 years, in 1918, 1957 and 1968. Scientists predict that another pandemic will happen, although they cannot say exactly when. They also don't know if the next pandemic will be mild, moderate, or severe.
- Pandemics and Pandemic
Scares in the 20th Century
The Department of Health and Human Services (DHHS) has compiled a summary of the pandemics and "pandemic scares" that have occurred in the last 100 years. Attention: Non-MDH link
You are more likely to catch it than ordinary flu because it spreads rapidly and very few people will have any immunity to it. Everyone will be at risk. Some groups of people may be more at risk than others. With ordinary flu the groups of people more likely to become seriously ill include:
- The very young
- People over 65 years of age
- People with existing medical conditions such as lung diseases, diabetes, cancer, kidney, or heart problems
- People who have immune system problems because of certain medical treatments, or illnesses like HIV/AIDS
These groups may be different during a pandemic.
In Minnesota, more than 75,000 people got sick, and over 7,500 died just during October, 1918.
News: Sunday, Oct. 13, 1918: Flu Epidemic Closes Churches, Schools, Dance
Star and Tribune headlines, stories and photographs from 1918. Attention: Non-MDH link
- Minnesota State Summit: History Supplement
Remarks by HHS Secretary Honorable Mike Leavitt about the 1918 pandemic in Minnesota. Attention: Non-MDH link
In 1918, pandemic influenza spread across the country in less than a month. Now, in the era of international air travel, a new pandemic will probably spread even faster, reaching Minnesota quickly after it is identified. Since everyone in the country would be hit pandemic at about the same time, we shouldn't expect help from other states.
Many people will get sick, and some will die. We expect that around 25% or 30% of our population might get the disease over the course of several months, and around two percent will die. People won't be able to come to work because they are sick, are caring for someone who is sick, or are scared they will get sick from others at work, so absenteeism rates may be very high. Services in your community, such as utilities, grocery stores, and public transportation may be disrupted. Schools may close.
Hospitals and clinics will be very full, and will be completely overwhelmed. Many people will be cared for at home. Others may get care at huge sites like the Metrodome.
Eventually there will be a vaccine, but it will take months to be produced, and there won't be enough for everyone at first.
In 1918, schools were closed several times. Teachers were asked to help with the pandemic; students were asked to stay home. Schools were also closed in some places during the SARS outbreak of 2003. Schools often experience outbreaks of seasonal influenza in Minnesota.
During the next pandemic, the Minnesota Department of Health might recommend school closures. The governor has the authority to declare a state of emergency, at which point he could close schools and other public gatherings.
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 mutates 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 scientists identify a pandemic strain, a matching vaccine will be developed. It takes 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, in time to prevent a second or third wave of illness.
You Can Do To Prepare for Pandemic
Fact sheet from MDH to help you prepare.
Things You Need to Know About Pandemic Influenza
WHO fact sheet giving an overview of possible effects of influenza pandemic. Attention: Non-MDH link
- General Information - PandemicFlu.gov
Overview of pandemics, and the possible pandemic threat we're facing right now. Attention: Non-MDH link