What is H1N1?

What is H1N1 Flu?

H1N1 flu is a respiratory disease of pigs caused by type A influenza that regularly causes outbreaks of influenza among pigs. H1N1 flu viruses do not normally infect humans; however, human-to-human spread of H1N1 flu virus is occurring, similar to the spread of regular seasonal flu viruses.

What causes H1N1?

It was caused by a particular strain of the influenza virus, just like any other flu. This particular strain (Influenza A, Novel H1N1 or 2009 Swine Flu virus) originated in pigs (swine) but has changed itself to be infective to humans.
Swine flu is a virus that originally infected only pigs and they spread it from one infected hog to other hogs the same way it spreads in people, by direct contact or by droplets holding the virus in the air after a pig coughed or sneezed. Because pigs are physiologically very similar to humans, when they have been living closely with humans, some microbes that can infect them are able to be changed or mutated into strains that people can catch. These types of diseases that we can get from animals are called zoonotic diseases.

What are the symptoms of H1N1?

The symptoms of H1N1 flu in people appear to be similar to the symptoms of regular seasonal flu and include:

• fever of more than 100 degrees Fahrenheit
• cough
• sore throat
• muscle aches
• headache
• chills
• fatigue
• diarrhea
• vomiting

Initial outbreaks

It is not known where the virus originated. Analysis has suggested that the H1N1 strain responsible for the current outbreak first evolved around September 2008 and circulated in the human population for several months before the first cases were identified as being due to a new strain.

Mexico

The virus was first reported in two U.S.children in March, but health officials have said that it apparently infected people as early as last January in Mexico. The outbreak was first detected in Mexico City on March 18, 2009 where surveillance began picking up a surge in cases of influenza-like illness. "In early April, Mexico had noticed that it had high numbers of serious respiratory illnesses and some deaths. It began sending samples to Canada and the United States, asking for help genotyping the new virus." Health Secretary Jose Angel Cordova confirmed that a 4-year-old boy was part of an outbreak in Veracruz state that began in February. Residents of the town of Perote worried at the time that they had contracted a new and aggressive flu, and publicly demonstrated against the pig farm they initially blamed for their illness. It was only after U.S. labs confirmed a swine flu outbreak that Mexican officials sent the boy's sample in for testing, and it tested positive for swine flu. While there was speculation that the outbreak may have started at the pig plant in Veracruz, the plant owners said that no pigs had tested positive for the virus.

After the outbreak was officially announced, Mexico immediately requested material support from the U.S. and worked closely with the CDC and Canada, sending them suspected samples for testing. Soon after, the CDC helped Mexico build their own lab capability to do faster diagnosis and confirmation of the H1N1 virus in Mexico. According to one commentator, "in the face of mounting hysteria, the response of both Mexico and the United States was an almost perfect display of the cooperation and partnership . . . ." Within a few days Mexico City was "effectively shut down," and some countries hastily canceled flights to Mexico while others halted trade. Although many in the U.S. called for shutting the border to help contain the spread, President Obama rejected the idea and Homeland Security Secretary Janet Napolitano called it "pointless," as the virus had already crossed into the U.S., and felt that "closing the border would have done nothing more than wreak economic havoc on both economies."

Prevention

 

What can I do to protect myself from getting sick?

There is no vaccine available right now to protect against novel H1N1 virus. There are everyday actions that can help prevent the spread of germs that cause respiratory illnesses like influenza.

 

Take these everyday steps to protect your health:

• 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 hand cleaners are also effective.
• Avoid touching your eyes, nose or mouth. Germs spread this way.
• Try to avoid close contact with sick people.
• Stay home if you are sick for 7 days after your symptoms begin or until you have been symptom-free for 24 hours, whichever is longer. This is to keep from infecting others and spreading the virus further.

Other important actions that you can take are:

• Follow public health advice regarding school closures, avoiding crowds and other social distancing measures.
• Be prepared in case you get sick and need to stay home for a week or so; a supply of over-the-counter medicines, alcohol-based hand rubs, tissues and other related items might could be useful and help avoid the need to make trips out in public while you are sick and contagious.

What is the best way to keep from spreading the virus through coughing or sneezing?

If you are sick, limit your contact with other people as much as possible. If you are sick, stay home for 7 days after your symptoms begin or until you have been symptom-free for 24 hours, whichever is longer. Cover your mouth and nose with a tissue when coughing or sneezing. Put your used tissue in the waste basket. Then, clean your hands, and do so every time you cough or sneeze.

 

 

 

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Short Quiz

1. H1N1 flu is a respiratory disease of pigs caused by type A influenza that regularly causes outbreaks of influenza among pigs.

2. Symptoms of H1N1 are cough, sore throat, muscle aches, headaches and fever of more than 100 degrees Fahrenheit.

3. The outbreak was first detected in Mexico city.

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Information prepared by Choo Teng