To better understand the H1N1 (swine flu) virus, David Ritchie, Pharm.D., BCPS, professor of Pharmacy Practice and infectious disease clinical pharmacist, answers some commonly asked questions about the virus and explains how you can protect yourself.
What is the swine flu?
Swine Influenza, or swine flu, is a respiratory disease caused by type A influenza viruses. The swine influenza viruses are contagious and can spread from pigs to people and from people to pigs and people to people.
In late March 2009, cases of human infection with swine influenza A (H1N1) viruses were first reported in Southern California and near San Antonio, Texas. Since then, other U.S. states have reported cases of swine flu infection in humans. Cases also have been reported internationally.
How can swine flu be passed from person to person?
At this time, it is not known how easily the virus spreads between people, but the virus is thought to be spread the same way seasonal influenza is spread - from person to person through coughing or sneezing of infected people. When an infected person coughs or sneezes into his or her hand and then touches something with that same hand the virus can be spread to the next person who touches that item and then touches his or her mouth or nose. The infected person can infect others beginning a day before their own symptoms develop and up to a week after becoming ill. Children may be contagious for an even longer period.
What are the best swine flu preventative measures a person can take?
The measures to prevent swine flu are similar to preventing other viruses from infecting your body. The best way to protect yourself is to regularly wash your hands, especially before touching your nose or mouth. Wash with soap and warm water for 15-20 seconds or use alcohol-based sanitizers when soap and water are not available. Also, maintain your overall health by coughing or sneezing into a tissue and then throwing the tissue away, be physically active, drink fluids, eat nutritiously, avoid close contact with people who are sick, and stay home to rest if you are not feeling well.
How do antiviral drugs, like Tamiflu, help prevent a person from contracting swine flu?
Antiviral drugs are prescription medicines that come in pill, liquid, or inhaler form with activity against influenza viruses. Some antiviral drugs can be used to treat swine flu or to prevent infection with swine flu viruses. These medications must be prescribed by health care professionals.
Influenza antiviral drugs only work against influenza viruses - they will not help treat or prevent symptoms caused by infection from other viruses that can cause symptoms similar to the flu. Laboratory tests on the swine influenza A H1N1 virus, which has infected people in the United States and Mexico, indicate that the virus is sensitive to the influenza antiviral drugs oseltamivir and zanamivir. These drugs can make the flu milder, decrease duration of symptoms, and work best when taken within 48 hours of getting sick. Influenza antiviral drugs also can be used to prevent influenza when they are given to someone who has been or may be near a person with swine influenza. When used to prevent influenza, antiviral drugs are about 70 -90 percent effective.
What drugs can I get from pharmacy to help prevent or treat swine flu?
While antiviral drug recommendations for prevention and treatment of swine flu may change as more is learned of the virus, the CDC recommends oseltamivir and zanamivir as most effective in preventing and treating swine flu. Oseltamivir (Tamiflu) is recommended to treat and prevent influenza A and b in people age one and older. Zanamivir (Relenza) is approved to treat influenza A and b in people 7 years and older and prevent influenza A and b virus infections in people 5 years and older.
What are symptoms of the swine flu? What should I do if I am experiencing these symptoms?
The symptoms of swine flu in people are thought to be similar to the symptoms of seasonal influenza, which includes fever, lethargy, lack of appetite, and coughing. Other less commonly reported symptoms of swine flu include runny nose, sore throat, nausea, vomiting, and diarrhea. If you are experiencing these symptoms, contact your health care provider for advice.
Will the flu shot I received this winter prevent me from being affected by swine flu?
No. The makeup of the H1N1 swine flu viruses, which have been found in the U.S. and Mexico, are very different from human H1N1 viruses. Therefore, human seasonal flu vaccines will not provide protection from H1N1 swine flu viruses. There is currently no vaccine to protect humans from swine flu.