H1N1 General Facts and Information
Novel Influenza A (H1N1) Virus (swine flu)
From the California Department of Public Health
Facts and General Information for the Public
What is Novel Influenza A (H1N1) Virus (swine flu)? Novel H1N1 (also referred to as "pandemic (H1N1) 2009 virus" or “swine flu”) is a new influenza virus causing illness in people. This new virus was first detected in people in the United States in April 2009. This virus is spreading from person-to-person worldwide, probably in much the same way that regular seasonal influenza viruses spread. This virus was originally referred to as “swine flu” because laboratory testing showed that many of the genes in this new virus were very similar to influenza viruses that normally occur in pigs in North America. But further study has shown that this new virus is very different from what normally circulates in North American pigs. It has two genes from flu viruses that normally circulate in pigs in Europe and Asia and avian genes and human genes. Scientists call this a "quadruple reassortant" virus. Human infections with the new H1N1 virus are ongoing in the United States. Most people who have become ill with this new virus have recovered without requiring medical treatment. Flu viruses are spread mainly from person to person through coughing or sneezing by people with influenza. Sometimes people may become infected by touching something (such as a surface or object) with flu viruses on it and then touching their mouth or nose.
The symptoms of H1N1 flu virus in people are similar to the symptoms of seasonal flu and include fever, cough, sore throat, runny or stuffy nose, body aches, headache, chills and fatigue. A significant number of people who have been infected with this virus also have reported diarrhea and vomiting. Also, like seasonal flu, severe illnesses and death has occurred as a result of illness associated with this virus. Recommendations are available if you are taking care of a sick person in your home.
The 2009 H1N1 vaccine is expected to be available in the fall. More specific dates cannot be provided at this time as vaccine availability depends on several factors including manufacturing time and time needed to conduct clinical trials. Monitor information from your provider and local health department to find out when and where the vaccine will be available. The seasonal flu vaccine is not expected to protect against the 2009 H1N1 flu.