Swine Flu Symptoms
Swine Flu Symptoms
What is H1N1 (swine) flu?
H1N1 Influenza (swine flu) is a respiratory disease of pigs caused by type A influenza viruses. Outbreaks of swine flu happen regularly in pigs. People do not normally get swine flu, but human infections can and do happen. Most commonly, human cases of swine flu happen in people who are around pigs but it’s possible for swine flu viruses to spread from person to person also.
Why is this new H1N1 virus sometimes called “swine flu”?
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.
Are there human infections with H1N1 (swine) flu in the U.S.?
In late March and early April 2009, cases of human infection with swine influenza A (H1N1) viruses were first reported in Southern California and near San Antonio, Texas. CDC and local and state health agencies are working together to investigate this situation. An updated case count of confirmed H1N1 (swine) flu infections in the United States is kept at http://www.cdc.gov/swineflu/investigation.htm. CDC and local and state health agencies are working together to investigate this situation.
How many H1N1 (swine) flu viruses are there?
Like all influenza viruses, swine flu viruses change constantly. Pigs can be infected by avian influenza and human influenza viruses as well as swine influenza viruses. When influenza viruses from different species infect pigs, the viruses can reassort (i.e. swap genes) and new viruses that are a mix of swine, human and/or avian influenza viruses can emerge. Over the years, different variations of swine flu viruses have emerged. At this time, there are four main influenza type A virus subtypes that have been isolated in pigs: H1N1, H1N2, H3N2, and H3N1. However, most of the recently isolated influenza viruses from pigs have been H1N1 viruses.
How serious is H1N1 (swine) flu infection?
Like seasonal flu, H1N1 (swine) flu in humans can vary in severity from mild to severe. Between 2005 until January 2009, 12 human cases of swine flu were detected in the U.S. with no deaths occurring. However, swine flu infection can be serious. In September 1988, a previously healthy 32-year-old pregnant woman in Wisconsin was hospitalized for pneumonia after being infected with swine flu and died 8 days later. A swine flu outbreak in Fort Dix, New Jersey occurred in 1976 that caused more than 200 cases with serious illness in several people and one death.
How severe is illness associated with this new H1N1 virus?
It’s not known at this time how severe this virus will be in the general population. CDC is studying the medical histories of people who have been infected with this virus to determine whether some people may be at greater risk from infection, serious illness or hospitalization from the virus. In seasonal flu, there are certain people that are at higher risk of serious flu-related complications. This includes people 65 years and older, children younger than five years old, pregnant women, and people of any age with chronic medical conditions. It’s unknown at this time whether certain groups of people are at greater risk of serious flu-related complications from infection with this new virus. CDC also is conducting laboratory studies to see if certain people might have natural immunity to this virus, depending on their age
Is this H1N1 (swine) flu virus contagious?
CDC has determined that this virus is contagious and is spreading from human to human. However, at this time, it not known how easily the virus spreads between people.
What are the signs and symptoms of H1N1 (swine) flu in people?
The symptoms of H1N1 (swine) flu in people are similar to the symptoms of regular human flu and include fever, cough, sore throat, body aches, headache, chills and fatigue. Some people have reported diarrhea and vomiting associated with H1N1 (swine) flu. In the past, severe illness (pneumonia and respiratory failure) and deaths have been reported with H1N1 (swine) flu infection in people. Like seasonal flu, H1N1 (swine) flu may cause a worsening of underlying chronic medical conditions.
In adults, emergency warning signs that need urgent medical attention include:
Currently, the CDC is recommending the antiviral drugs Oseltamivir (®) or Zanamivir (Relenza®).
Healthy Habits: Learn tips to help you stay healthy
Track the progress of the H1N1 Virus across the United States with the new H1N1 Map.
