As the number of swine flu cases grows, so do the questions about how the virus is transmitted and what people can do to prevent it. Here are answers from interviews with doctors and from public-health Web sites.
Q. How do I know if I have swine flu?
A. If you have a fever, chills and body aches, see a healthcare professional. Watch for the typical symptoms associated with the seasonal flu.
Q. If I got a flu shot in September, will it protect me against the swine flu?
A. "We really don't know for sure," said Dr. Nikhill Bhayani, an infectious-disease physician with Texas Health Arlington hospital. "There could be some residual immunity. There is no point in getting a flu vaccine at this point."
Q. If I got the swine flu vaccine in 1976, will it protect me now?
A. No. The virus has mutated, Bhayani said.
Q. Will antibiotics help?
A. Antibiotics are effective for bacterial infections and not viral infections, such as the swine flu. Antiviral drugs are being prescribed for the swine flu.
Q. How is the virus transmitted?
People usually get swine flu from infected pigs, but the type making people sick now is also transmitted from human to human. When an infected person sneezes, the virus can travel a few feet; it can live on doorknobs, keyboards and other objects. That's why handwashing is so important.
Q. What is the incubation period?
A. It's estimated at five to seven days.
Q. Can I get swine flu from eating pork or produce from Mexico?
A. The swine flu is not spread by food. Eating properly handled and cooked pork is safe, according to the Centers for Disease Control and Prevention.
Q. Do masks help?
A. Masks are an effective way to prevent the spread of viruses, Bhayani said.
Q. Why are so many children, teens and young adults getting it?
A. Children's immune systems are still evolving, Bhayani said, and they have not yet been exposed to a wide variety of illnesses.
Q. When does an influenza outbreak become a pandemic?
A. According to the World Health Organization, a pandemic occurs when a new viral strain that can infect humans is associated with a high mortality rate and is easily transmissible from person to person.
Q. How many influenza pandemics have there been?
A. Three, in 1918, 1957 and 1968. The Spanish Flu of 1918 lasted a little over a year and killed about 500,000 people in the United States and over 20 million worldwide. The Asian Flu of 1957 lasted from February to December and killed nearly 69,000 people in the U.S. The Hong Kong Flu of 1968 lasted a little over a year and killed 33,800.
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Distributed by McClatchy-Tribune Information Services.
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