H1N1 (swine) flu

CDC 2009

-March/April 2009, an outbreak of H1N1 influenza A virus infection was first detected in Mexico.

-June 11, 2009, WHO raised its pandemic alert level to the highest level, phase 6, indicating widespread community transmission on at least two continents.

Age distribution:

Oddly infection occurs disproportionately in individuals who are not at the extremes of age.

Distrubtion ages 5 and 24-years-old.

Few cases and no deaths reported in people older than 64 years old (? previous immunity)

High-risk groups:

Pregnant- incr rates of SAB, preterm labor

Chronic lung disease

Immunosuppressed

Cardiac

DM

Screening:

Individuals with an acute febrile respiratory illness (a measured temperature of 100ºF or higher and recent onset of at least one of the following: rhinorrhea, nasal congestion, sore throat, or cough) or sepsis-like syndrome- HIGH PRIORITY for hospitalized patients and those at high-risk for severe disease.

Tests:

Rapid Flu nasal swab 60-80% sensitive in detecting influenza A

If patient is negative, severely ill and will be hospitalized, send viral culture

PCR is the recommended confirmatory test

Treatment:

• All hospitalized patients with confirmed, probable or suspected novel influenza (H1N1).
• Patients who are at higher risk for seasonal influenza complications

Most effective when started within 48 hours of illness onset.

Adult: 75-mg capsule twice per day for 5 days

Post-exposure antiviral chemoprophylaxis is recommended for those with close contacts:

Tamiflu 75mg po daily x 10 days (10 days after the last known exposure to novel (H1N1) influenza.)

If the contact occurred with a patient after 7 days of symtpom onset, then chemoprophylaxis is not necessary. This is the presumed post-infectious period.