Swine Flu Reality Check Where flu pandemics hit present and past, with advice on what to do about it.

May 1, 2009 -- States reporting new cases of swine flu are lighting up the country like election night. Celebrities, meanwhile, are wearing masks, thousands of children will be out of school for weeks, and many are cancelling their travel plans for fear of a virus that is currently on level 5 out of 6 on the World Health Organizations pandemic alert level.

Swine flu may sound nasty. As of late Thursday, there are 236 cases of swine flu and eight confirmed deaths worldwide.

But by comparison an estimated 600 people die of tuberculosis, about 1,400 people die from strep and 2,704 people die from a common asbestos-related lung cancer in the United States every year.

Last year the seasonal flu took the lives of 83 children and an estimated 36,000 adults in the United States, according to the CDC.

The head of the CDC's influenza division, Dr. Nancy Cox, said today that preliminary research suggests the swine flu virus lacks many of the "markers for virulence" possessed by the H1N1 pandemic virus of 1918.

Because the virus lacks these key components of the virus that killed between 30-50 million people nearly a century ago, she suggested that the swine flu may not be as deadly.

"What we have found by looking very carefully at the sequence of the new H1N1 virus is that we're not seeing the markers for virulence that we saw in 1918 virus," she said.

Of course, pandemics can be deadly and need public health measures.

But in every flu pandemic since 1918, the numbers have luckily dwindled. The 1957-1958 pandemic flu took 70,000 deaths above the normal flu season, and the 1968-1967 pandemic flu caused 33,000 more deaths than the average flu season. The virulence of the virus does matter, but public health measures can clearly make a huge difference.

The following are some of the quick facts on the swine flu outbreak so far.

How Worried Are Americans?

The Harvard School of Public Health conducted a national poll on swine flu this week, the results of which were released Friday. According to the results:

46 percent of Americans are concerned about catching swine flu in the next year;

20 percent, are "very" concerned about it;

53 percent not concerned about encountering the swine flu over the next 12 months.

But that doesn't mean Americans aren't taking precautions. In response to the outbreak:

59 percent of respondents say they have washed their hands or used a hand sanitizer more frequently; 25 percent have avoided crowded places; 20 percent have avoided people they think may have recently visited Mexico; 17 percent have avoided Mexican restaurants or grocery stores; 8 percent have worn a face mask; 5 percent have talked with their doctor about swine flu; 1 percent have gotten a prescription for or purchased antivirals such as Tamiflu or Relenza.

Swine Flu Cases in the United States

Arizona: 4

California: 13

Colorado: 2

Connecticut: 1 *

Delaware: 4

Florida: 2 *

Georgia: 1 *

Illinois: 3

Indiana: 3

Kansas: 2

Kentucky: 1

Maine: 3 *

Massachusetts: 2

Michigan: 2

Minnesota: 1

Nebraska 1

Nevada: 1

New Jersey: 5

New York: 50

Ohio: 1

South Carolina: 16

Texas: 28 cases, 1 death

Virginia: 2

* These cases have been reported by state health officials, but have not yet been confirmed by the Centers for Disease Control and Prevention.

U.S. Swine Flu News

More than 332,000 students nationwide are out of school due to closures in 21 states.

The CDC has confirmed a total of 144 cases in 21 states.

About 400 students had flu-like symptoms at the University of Delaware, state officials reported Thursday. Of them, at least four cases have been confirmed by local officials.

Georgia announced its first confirmation of swine flu Thursday in a 30-year-old Kentucky woman who fell ill on a trip to the western part of the state. State officials have said the CDC has confirmed this case.

Wednesday a small cluster of infections appeared to be emerging in Washington state, which if confirmed would mean the virus would have spread to 19 states.

South Carolina officials reported 10 confirmed cases of swine flu among students who recently took a trip to Mexico.

Arizona announced its first confirmed case of swine flu April 29, the same day that neighboring Nevada announced its first case.

New England gained its first cases of swine flu April 29, after two people were confirmed to have the virus in Massachusetts. Maine also confirmed three cases in the state April 29 -- all adults who were reportedly recovering in their homes, according to Gov. John Baldacci.

Michigan joined the list of states with confirmed cases April 29, and now has a total of two people diagnosed with swine flu.

California was the first state to confirm a case of swine flu on April 21. Since then, 14 of cases in ages ranging from grade school to adults have been confirmed in Sacramento and southern California.

On April 29, officials confirmed that a Marine at Twentynine Palms military base had come down with the swine flu. In response the base quarantined 30 marines. Gov. Arnold Schwarzenegger declared a state of emergency in California on April 28 to release funds to fight the outbreak.

Texas had the first death in the United States from the swine flu: a 22-month-old boy died April 27 in a Houston hospital. A total of 26 of people have been diagnosed with swine flu in Texas. The Fort Worth Independent School District decided to close all schools, likely until May 11th to stem further infections.

New York has seen the largest number of confirmed swine flu cases after the first few were detected in California and Texas. A cluster of swine flu cases confirmed at St. Francis Preparatory School has since spread to a total of 51 cases across New York City.

Swine Flu at Home, and Abroad

Neighboring Indiana announced its first case of swine flu just days later on April 29. Health officials confirmed that a student at Notre Dame fell ill.

A Kansas couple represented the first -- and only -- cases to be diagnosed in the state April, 25 apparently after the husband traveled to Mexico for professional conference. Officials described their case as mild and said the couple cooperated in quarantining themselves.

On April 27 the U.S. Department of State issued a travel advisory against unnecessary trips to Mexico, as did the top European Union health officials.

Swine Flu Around the World

International Swine Flu Cases

The WHO has officially confirmed 331 cases of swine flu and 10 deaths. The numbers increase according to each country's official tally.

Mexico: 156 cases, 7 deaths. United States: 141 cases, 1 death Austria: 1 case Canada: 34 cases Germany: 3 cases Israel: 2 cases New Zealand: 3 cases Peru: 1 case Spain: 13 cases Switzerland: 1 case Netherlands: 1 case United Kingdom: 8 cases

The WHO announced suspected cases under investigation in at least 15 other countries.

International Swine Flu News

Mexico's government suspects nearly 2,300 cases of swine flu and 159 possibly-related deaths; yet the WHO organization only reports 97 cases in that country.

The Netherlands and Switzerland both reported their first case each yesterday.

Germany, Austria and New Zealand confirmed cases of swine flu Wednesday, April 29.

A South Korean Catholic nun traveling in Mexico has tested positive for swine flu, according to reporting by ABC's Joohee Cho. South Korean authorities believe the 51-year-old woman caught the disease from a taxi driver and have requested the Mexican government look into the matter.

South Korea and Ukraine have temporarily banned all pork imports from North America in response to flu concerns, despite the WHO advisory that the virus is not transferred by eating well-cooked pork and pork products.

Suspected cases are being investigated in at least 14 countries, including: South Korea, Australia, Brazil, Chile, France and South Africa.

Officials around the world have taken measures from closing schools to screening people's body heat checking for fevers at airports.

How to Protect Yourself

The CDC recommends the following steps to protect yourself from flu.

Cover your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash after you use it.

Wash your hands often with soap and water, especially after you cough or sneeze. Alcohol-based hands cleaners are also effective. Doctors say the biggest mistake many make is to just do a quick rinse under the faucet while washing their hands.

Avoid touching your eyes, nose or mouth. Germs spread that way.

Try to avoid close contact with sick people. Influenza is thought to spread mainly person-to-person through coughing or sneezing of infected people.

If you get sick, CDC recommends that you stay home from work or school and limit contact with others to keep from infecting them.

What Are the Symptoms of Swine Flu?

The World Health Organization is working to develop a profile of the "typical case" of swine flu, but thus far, the symptoms appear to be essentially the same as those for the usual winter flu. Hallmark symptoms of flu include:

High fever

Muscle aches

Headache

Fatigue

Coughing

Runny nose

Vomiting and Diarrhea (less common)

Sources: the CDC, the World Health Organization, and the National Institute of Allergy and Infectious Diseases

The Associated Press Contributed to this report