Q&A: Basic Information About Swine Flu

NPR Coverage CDC: Swine Flu Cases Confirmed In Five States

Public health officials around the world, including the Centers for Disease Control and Prevention and the World Health Organization, are taking steps to monitor and contain an outbreak of a new variation of swine flu. Following are questions and answers about the illness:

What is swine flu?

Swine flu is a highly contagious respiratory disease in pigs. The disease is caused by a virus and causes sickness in the animals, but has a low death rate. The virus frequently circulates among the animals throughout the year, with outbreaks more common in the fall and winter.

How do people become infected?

The CDC says the spread of swine flu can occur in two ways: through contact with infected pigs or environments contaminated with the virus; or through contact with a person with swine flu. The CDC has determined that the virus is contagious and spreading among people, but at this time it is not known how easily that happens.

Is this a pandemic?

No, not yet, at least. But it is considered an outbreak, or a sudden increase in the numbers of a particular illness. What caused doctors in Mexico to sit up and take notice was a sudden jump in serious pneumonias at the end of the regular flu season. Tests are under way now to determine how many of these cases might be swine flu.

A pandemic is a worldwide outbreak of disease, typically affecting millions of people. An epidemic is a disease that spreads rapidly and widely in a localized region or country. And since officials aren't sure how many of the cases are actually swine flu, it's still too early to call it an epidemic.

The World Health Organization, one of the groups monitoring the situation and coordinating an international response to the swine flu outbreak, currently has the situation listed as "Phase 3," on a six-step scale, which means that though the disease has affected small clusters of people, the swine flu "has not resulted in human-to-human transmission sufficient to sustain community-level outbreaks."

WHO officials have called the outbreak a "public health emergency of international concern," but have so far held off raising the pandemic level any higher. Phases 4 and higher represent significant human-to-human spread of the virus both at a community level and worldwide.

If this isn't yet a pandemic, why the alarm?

Officials don't yet know how contagious the disease is or exactly how it's spreading, but the high number of cases as well as the geographic distribution has them on the lookout for more cases, which are expected to be found. Influenza viruses, like the swine flu, can be transmitted between people by coughing or sneezing, or by touching something with a flu virus on it.

How serious is the swine flu infection, and can it be treated?

The CDC reports that like the seasonal flu, the swine flu infection ranges from mild to severe. Between 2005 and January 2009, the CDC reported only 12 cases of swine flu in the U.S., with no deaths. But swine flu outbreaks in 1988 and 1976 were responsible for at least two deaths.

While there is currently no human vaccine for the strain of swine flu virus seen in the current outbreak, there are four antiviral drugs approved for use in the U.S., but only two are known to be effective against the virus seen in this outbreak — the drugs oseltamivir (Tamiflu) and zanamivir (Relenza).

How does swine flu differ from the 'regular' seasonal flu?

The swine flu virus currently circulating is a new virus, which means it is not likely that many people are immune. The WHO says that if the virus establishes strong enough transmission between humans, the risk for a pandemic increases. And since researchers aren't precisely sure how the virus is transmitted, their concern about rapid spreading is high.

Seasonal flu, which sickens between 5 and 20 percent of the population and kills about 36,000 people each year, can most often be prevented with a flu vaccination.

What about a flu shot or vaccine?

Unfortunately there are no drugs specifically targeted toward this new strain of swine flu, and if you've already received a flu shot this year, you're not protected. Developing and mass-producing vaccines can take up to six months, but scientists now say they have enough samples of the virus to begin that work.

What is the U.S. plan to combat swine flu?

The acting secretary of the Department of Health and Human Services has declared a "Public Health Emergency," a move that Department of Homeland Security Secretary Janet Napolitano says "sounds more severe than it really is," but gives health officials easier access to flu tests and medications.

The CDC is also working with state and local health agencies to monitor and track cases of the virus. Clinicians who suspect they might be treating a patient are being advised to send a swab sample to the state's public health laboratory for further testing.

What are the symptoms of swine flu in humans?

In humans, the symptoms of swine flu are similar to regular seasonal flu — fever, sore throat, cough, body aches, chills, fatigue and headaches.

Health officials recommend seeing a physician if symptoms develop. The physician will decide if a test for swine flu is necessary.

What can I do to protect myself?

Though the exact means of transmission between people is not known, the CDC recommends following the basic health principles below to stay healthy:

Cover your nose and mouth with a tissue when you sneeze, and throw the tissue away after using it

Wash your hands often with soap and water. Alcohol-based hand sanitizers are also effective

Avoid close contact with sick people

Avoid touching your nose, eyes, or mouth

Can I get sick from eating pork and pork products?

No. The World Health Organization says that swine flu has not been shown to be transmissible through properly handled pork or other food products derived from pigs. Regardless, the virus is killed if the meat is cooked to the recommended temperature of 160 degrees Fahrenheit.

Does wearing a face mask help?

According to the CDC, "very little is known about the benefits of wearing face masks and respirators to help control the spread of pandemic flu." But in the absence of clear science, the CDC has issued guidelines for wearing face masks and respirators.

A face mask, like the kind your dentist wears, is a loose-fitting disposable mask that covers your nose and mouth. Face masks only help prevent contact with droplets, like those from a sneeze. The CDC recommends wearing a face mask if:

You are sick with the flu and might have close contact with others

If you live with someone with the flu, and might be in a crowded place

You are healthy and don't expect to be in close contact with a sick person, but need to be in a crowded place

A respirator fits snugly over the nose and mouth and protects the wearer from breathing in small particles by using a set of filters or other special material. They should be worn by people like caregivers, who might have extended exposure to sick people.

Sources: The Centers for Disease Control And Prevention, The World Health Organization, pandemicflu.gov