Influenza A/H1N1 is caused by type A influenza viruses. It is a highly contagious disease of the respiratory system. From late March to early April of 2009, human cases of contamination with swine influenza virus were reported in the United States, Mexico and throughout the world. It has been concluded that these specific cases were caused by a new virus called H1N1, and not the swine flu virus classic presentation. This newer form of the virus is cause for concern due to its human-to-human contamination ability. The direct swine flu differed in that it spread only via direct contact with contaminated swine. Currently, the mortality rate is sustained at approximately 0.5 %, with 209 countries being affected and suffering 14,000 deaths. There is an effective vaccine to fight the pandemic influenza A/H1N1 virus.

Illustration of influenza antigenic shift

Illustration of influenza antigenic shift

Immunity

Immunity as of this time, is in question. There are no known effective mechanisms.

Traveling Risks

The H1N1 virus is contagious and can be spread from human-to-human. Studies however on how easily it spreads are still being formulated. Currently, the spread is thought to occur in much the way that seasonal flus spread – via sneezing, touching infected areas and coughing. H1N1 is not spread through food. It cannot contaminate humans from preparing, or eating pork.

There are particular risks for people with diabetes, respiratory disease and cardiovascular diseases. This group has a higher risk of contracting the virus, and suffering more severe complications upon contraction. People over 65-years of age are considered high-risk, as are children between 6- to 23-months old.

Incubation of Influenza A/H1N1

After exposure, most patients show symptoms between two to eight days. Symptoms present as influenza-like in nature with body aches, sore throat, fever, runny nose, vomiting, diarrhea and nausea. In more severe cases, or with patients at higher risk, it can develop to pneumonia, respiratory difficulty and even failure, along with possible death. Influenza A/H1N1 may also aggravate existing chronic conditions.

Prevention Most Effective Preventative Activities

Hand washing has proven to be the most effective preventative activity. Using soap and water effectively, or using hand sanitizers, showed the most reliable action people can take to avoid contamination. Beyond that, keeping general health at its optimal along with adequate restful sleep can help with prevention. Also, avoiding contaminated surfaces and people who may be affected are ways to stay unaffected. Any experience however with joint pain, fever or headache should be addressed with formal medical assessment immediately.

Treatment – Effective Drugs

Antiviral drugs can be used during treatment. Both zanamivir and oseltamivir are recommended effective drugs. Any experience of flu-like symptoms post possible contamination, should be addressed formally by a medical professional. Antiviral drugs may be prescribed and can ease flu-like symptoms. Efficacy is most reliable within 2 days of contamination and presentation of symptoms.