Distributed via Health Alert Network
April 26, 2009,11:00 EST (11:00AM EDT)
Public health officials within the United States and throughout the world are investigating outbreaks of swine influenza (swine flu).
Swine flu is a respiratory disease of pigs caused by a type A influenza virus that regularly causes outbreaks of influenza among pigs. Swine flu viruses do not normally infect humans; however, human infections with swine flu do occur. Public health officials have determined that this strain of swine flu virus spreads from human to human and can cause illness.
The outbreak is ongoing and additional cases are expected. For more information concerning swine flu infection, please see the Centers for Disease Control and Prevention (CDC) website: http://www.cdc.gov/swineflu/. For specific information on travel precautions and an update on the affected areas, please visit: www.cdc.gov/travel.
The symptoms of swine flu in people are similar to the symptoms of seasonal flu in humans and may include:
Some people have reported diarrhea and vomiting associated with swine flu. Severe illness (pneumonia and respiratory failure) and deaths have been reported with swine flu infection in people. Like seasonal flu, swine flu may cause a worsening of underlying chronic medical conditions.
People entering the United States who are experiencing symptoms consistent with swine flu and have traveled to an affected area (see http://www.cdc.gov/swineflu/investigation.htm for affected areas), or have been exposed to someone possibly infected with swine flu, during the last 7 days should report their illnesses to their health care provider immediately and inform them of their recent travel.
People traveling from the United States to affected areas should be aware of the risk of illness with swine flu and take precautions.
For more information:
Distributed via Health Alert Network
April 25, 2009, 3:00 EST (03:00 PM EDT)
CDC, in collaboration with public health officials in California and Texas, is investigating cases of febrile respiratory illness caused by swine influenza (H1N1) viruses. As of 11 AM (EDT) April 25, 2009, 8 laboratory confirmed cases of Swine Influenza infection have been confirmed in the United States. Four cases have been reported in San Diego County, California. Two cases have been reported in Imperial County California. Two cases have been reported in Guadalupe County, Texas. Of the 8 persons with available data, illness onsets occurred March 28-April 14, 2009. Age range was 7-54 y.o. Cases are 63% male.
The viruses contain a unique combination of gene segments that have not been reported previously among swine or human influenza viruses in the U.S. or elsewhere.At this time, CDC recommends the use of oseltamivir or zanamivir for the treatment of infection with swine influenza viruses. The H1N1 viruses areresistant to amantadine and rimantadine but not tooseltamivir or zanamivir. It is not anticipated that the seasonal influenza vaccine will provide protection against the swine flu H1N1 viruses.
CDC has also been working closely with public health officials in Mexico, Canada and the World Health Organization (WHO). Mexican public health authorities have reported increased levels of respiratory disease, including reports of severe pneumonia cases and deaths, in recent weeks. CDC is assisting public health authorities in Mexico by testing specimens and providing epidemiological support. As of 11:00 AM (EDT) April 25, 2009, 7 specimens from Mexico at CDC have tested positive for the same strain of swine influenza A (H1N1) as identified in U.S. cases. However, no clear data are available to assess the link between the increased disease reports in Mexico and the confirmation of swine influenza in a small number of specimens. WHO is monitoring international cases. Further information on international cases may be found at: http://www.who.int/csr/don/2009_04_24/en/index.html
Clinicians should consider swine influenza infection in the differential diagnosis of patients with febrile respiratory illness and who 1) live in San Diego or Imperial counties, California, or Guadalupe County, Texas, or traveled to these counties or 2) who traveled recently to Mexico or were in contact with persons who had febrile respiratory illness and were in one of the three U.S. counties or Mexico during the 7 days preceding their illness onset.
Patients who meet these criteria should be tested for influenza, and specimens positive for influenza should be sent to public health laboratories for further characterization. Clinicians who suspect swine influenza virus infections in humans should obtain a nasopharyngeal swab from the patient, place the swab in a viral transport medium, refrigerate the specimen, and then contact their state or local health department to facilitate transport and timely diagnosis at a state public health laboratory. CDC requests that state public health laboratories promptly send all influenza A specimens that cannot be subtyped to the CDC, Influenza Division, Virus Surveillance and Diagnostics Branch Laboratory.
Persons with febrile respiratory illness should stay home from work or school to avoid spreading infections (including influenza and other respiratory illnesses) to others in their communities. In addition, frequent hand washing can lessen the spread of respiratory illness.
CDC has not recommended that people avoid travel to affected areas at this time. Recommendations found at http://wwwn.cdc.gov/travel/contentSwineFluUS.aspx will help travelers reduce risk of infection and stay healthy.
Clinical guidance on laboratory safety, case definitions, infection control and information for the public are available at:http://www.cdc.gov/swineflu/investigation.htm.
Morbidity and Mortality Weekly Reports Dispatch (April 24) provide detailed information about the initial cases at http://www.cdc.gov/mmwr/preview/mmwrhtml/mm58d0424a1.htm
For more information about swine flu: http://www.cdc.gov/swineflu
Additional information is also available by calling 1-800-CDC-INFO (1-800-232-4636)