Swine flu: facts, symptoms, protection
May 1, 2009 · 4:20 PM
By Ward Hurlburt, M.D.
Q: What is swine influenza (swine flu)?
A: Swine influenza (swine flu) is a respiratory disease of pigs caused by type A influenza virus that regularly causes outbreaks of influenza in pigs. Swine flu viruses cause high levels of illness and low death rates in pigs. Swine influenza viruses may circulate among swine throughout the year, but most outbreaks occur during the late fall and winter months similar to outbreaks in humans. The classical swine flu virus (an influenza type A H1N1 virus) was first isolated from a pig in 1930.
Q: How do humans catch swine flu?
A: Swine flu viruses do not normally infect humans. However, a few human infections of swine flu have occurred. Most commonly, people who have direct exposure to pigs contract the virus (i.e. children near pigs at a fair or workers in the swine industry).
Q: Should people be worried about this type of flu?
A: As a retired surgeon general’s assistant, we saw nationwide cases of influenza viruses. The number of cases of swine influenza in the United States is relatively small and it does appear that certain antiviral drugs may offer some relief. However, there is no human immunity to this particular virus.
Q: What are symptoms of swine flu in humans?
A: The symptoms of swine flu in people are similar to the symptoms of regular human seasonal influenza and include fever, lethargy, lack of appetite and coughing. Some people with swine flu also have reported runny nose, sore throat, nausea, vomiting and diarrhea.
Q: How does swine flu spread from pigs to humans?
A: Influenza viruses can be directly transmitted from pigs to people and from people to pigs. It is most likely that individuals who are in close proximity to infected pigs, such as in pig barns and livestock exhibits housing pigs at fairs, will get the virus. Human-to-human transmission of swine flu can also occur. This pretty much occurs in the same way that the seasonal flu occurs in people, which is mainly person-to-person transmission through coughing or sneezing of people infected with the influenza virus. People may become infected by touching something with flu viruses on it and then touching their mouth or nose.
Q: Can people catch swine flu from eating pork?
A: No. Swine influenza viruses are not transmitted by food. You can not get swine influenza from eating pork or pork products. Eating properly handled and cooked pork and pork products is safe. Cooking pork to an internal temperature of 160 degrees Fahrenheit kills the swine flu virus as it does other bacteria and viruses.
Q: How can I protect myself and others from the flu?
A: Practice good hygiene. If you or a family member is sick with a flu-like illness, please stay home from work. It’s important to practice frequent handwashing, covering coughs and having ill persons stay home, except to seek medical care, and minimize contact with others in the household who may be ill with swine flu. Additional measures that can limit transmission of a new influenza strain include voluntary home quarantine of members of households with confirmed or probable swine influenza cases, reduction of unnecessary social contacts and avoidance whenever possible of crowded settings. It’s important that you take preventive measures, such as avoiding close contact and maintaining good hand hygiene.
Q: How do you diagnose swine flu in humans?
A: To diagnose swine influenza A infection, a respiratory specimen would generally need to be collected within the first four to five days of illness (when an infected person is most likely to be shedding virus). However, some persons, especially children, may shed virus for 10 days or longer. See your physician immediately if you or your child shows symptoms.
Q: What medications are available to treat swine flu?
A: There are four different antiviral drugs that are licensed for use in the U.S. for the treatment of influenza: amantadine, rimantadine, oseltamivir and zanamivir. Although most swine influenza viruses have been susceptible to all four drugs, the most recent swine influenza viruses isolated from humans are resistant to amantadine and rimantadine. At this time, CDC recommends the use of oseltamivir or zanamivir for the treatment and/or prevention of infection with swine influenza viruses.
Q: How does swine flu spread among pigs?
A: Swine flu viruses spread mostly through close contact among pigs and possibly from contaminated objects moving between infected and uninfected pigs. Herds with continuous swine flu infections and herds that are vaccinated against swine flu may have sporadic disease, or may show only mild or no symptoms of infection.
The best advice I can give you is if you’re healthy, stay away from sick people and if you’re sick, stay away from healthy people.
Federal, state and local public health officials are doing an excellent job of staying on top of the current outbreak of swine flu. Information about the outbreak and recommendations for individuals or the public at large are rapidly being disseminated through newspapers, TV and radio. You should keep yourself informed regarding any updated recommendations related to this outbreak of swine flu.
Ward Hurlburt, M.D., is the chief medical officer of Molina Healthcare of Washington. He practices at Molina's Bothell office.