Eye on influenza - swine influenza

Eye on Influenza
April 24, 2009
Volume 5, Issue 13
Orange County Health Care Agency, Epidemiology & Assessment, 1719 W. 17th St. Santa Ana, CA 92706, (714) 834-8180 This situation is evolving rapidly; for the most up-to-date information about the investigation; see • Unique swine influenza virus detected in Southern California, Texas, and Mexico raises concern for human-to-human transmission. As of 4/24/09, eight human cases of novel swine influenza A (H1N1) have been confirmed in San Diego and Imperial Counties in California (6) and Guadalupe County near San Antonio, Texas (2), as well as in an unknown number in Mexico. All cases in the U.S. have been mild and have recovered but severe respiratory illness and deaths have been reported in Mexico. No cases in the U.S. reported recent exposure to pigs. The viruses from the first two cases are resistant to the antivirals amantadine and rimantadine, but susceptible to oseltamivir (Tamiflu®) and zanamivir (Relenza®); susceptibility testing on the other cases’ viruses is pending but is expected to be the same. For a summary of the first two ca (4/24/09 issue). • Enhanced surveillance for human swine influenza infections is critical to determine the extent of human-human transmission. Recommendations for enhanced surveillance for influenza-like illness (ILI) and the appropriate testing is being distributed to all hospitals, emergency departments, and outpatient sentinel providers participating in ILI surveillance in Orange County, and is posted at . • CDC interim guidance on infection control, treatment, and chemoprophylaxis for swine influenza is • Key facts about swine influenza in general (see : o Swine influenza (swine flu) is a respiratory disease of pigs caused by type A influenza viruses, o Swine flu viruses do not normally infect humans. However, sporadic human infections with swine flu do occur. Between December 2005 and February 2009, 12 human cases of swine flu were reported in the U.S. This does not include the recent cases in CA and TX. o Most commonly, human swine flu cases occur in persons with direct exposure to pigs (e.g., workers in the swine industry). Although it has been documented, human-to-human transmission is rare. o Symptoms of swine flu in humans are similar to those of seasonal influenza – fever, cough, malaise, and sometimes runny nose, sore throat, nausea, vomiting, and/or diarrhea. o Although most swine flu viruses have been susceptible to all four antivirals available for the treatment of influenza, the most recent two viruses isolated from humans have been resistant to amantadine and rimantidine. Therefore, CDC currently is recommending the use of oseltamivir or zanamivir for the treatment and/or prevention of infection with swine influenza viruses. o Seasonal influenza vaccine for humans may provide protection against swine H3N2, but not swine H1N1 viruses. Swine H1N1 viruses are very different from human H1N1 ones. o Healthy habits can help prevent infection: (1) Cover your mouth and nose when you cough or sneeze; (2) Wash your hands frequently; (3) Avoid sick people; (4) Stay home when you are sick; and (5) Avoid touching your eyes, mouth and nose. Seasonal Influenza in Orange County**, California,
Reported Seasonal Influenza Cases, by Week and Type, Orange
County, CA 2008-2009
and the U.S. to date
• No increases in confirmed influenza or influenza-like illness have been reported in Orange County. Over Data for Week 16 2009 is incomplete.
the past 6 weeks, there has been an increase in the relative proportion of reports for influenza B similar to what is being seen elsewhere in the U.S. CA flu **Note: The number of reported cases does NOT correspond to the total number of cases occurring in OC as not all hospitals/labs participate, the surveillance programs are not population based, and testing may be influenced by many factors such as public interest. However, the trends in influenza activity are likely to be reflected accurately. Specimen Disease Week & Approximate Month
If you have any comments about this flyer, contact Pamela Roa Hipp or Michele Cheung, MD, at (714) 834-8180. To receive this newsletter by email, please contact us at epi@ochca.com.

Source: http://www.coccc.org/resources/Swine%20Flu/Eye%20on%20Influenza.pdf