Dear Clinician:

A novel type A H1N1 variant of swine influenza has been found now in patients in several states in the US, as well as in Mexico. To date, the Kentucky Department for Public Health (KDPH) has not identified any cases of swine flu here in Kentucky. However, KDPH is investigating and testing some potential cases.

Since the outbreak is in the early stages nationwide, the science is not yet clear about how virulent this new strain might be or how readily transmissible it is. Nevertheless, in preparation for a possible worsening scenario, KDPH is issuing this information to providers.

CDC has listed interim case definitions on the following site: Though these are likely to change, in order to be classified now as a confirmed case, laboratory confirmation must occur. The Division of Laboratory Services at KDPH is able to determine whether a specimen is a known circulating human influenza strain. If results do not indicate that the specimen is a known circulating human strain, the Division of Laboratory Services will forward the specimen to the CDC for further analysis. The Division of Laboratory Services anticipates receiving reagents from the CDC when available for specific swine influenza typing in the near future.

Kentucky’s normal seasonal influenza season has not yet come to a close, and much of the circulating virus in the state this year has been found to be human H1N1 influenza. This situation results in a challenge for providers, both in terms of diagnosis and treatment.

KDPH is asking the health care community to be vigilant in recognizing influenza-like symptoms in patients and to treat appropriately. For now, the Division of Laboratory Services would like to receive specimens on patients that meet the CDC criteria for probable or suspected cases, or on those with influenza-like illness who have positive rapid influenza tests. Before sending to the Division of Laboratory Services, please call KDPH’s Departmental Operations Center at 1-888-398-0013 for tracking and guidance.

Though the newly-recognized swine influenza strain appears to be susceptible to neuraminidase inhibitors, much of the type A seasonal influenza that is circulating in Kentucky is likely not. If influenza is strongly suspected, please consider treatment with both a neuraminidase inhibitor and rimantadine or amantadine. If influenza is not suspected, please do not treat with the above antivirals, as overuse of them could result in changing susceptibility patterns. In addition, prescribing antivirals to patients for future use “just in case” could lead unintended consequences ( ) and to shortages of antivirals.

KDPH has limited stockpiles of antivirals that can be used for treatment if and when commercial supplies become exhausted. In addition, KDPH has asked CDC to send Kentucky 25% of the state’s allotment from the national stockpile to supplement our supplies. Spread of influenza can be prevented through proper handwashing.

Thank you for your willingness to work with us toward the identification, prevention and appropriate treatment of influenza. More information, including guidance for care of patients in the home, can be found at As the swine flu situation changes, more updates will be forthcoming.

Surveillance and Specimen Collection for Swine Influenza A (H1N1) Virus:

The Kentucky Department for Public Health is currently enhancing influenza surveillance activities to monitor for the presence of swine flu in Kentucky. Below are the current recommendations for swine flu surveillance and specimen collection in Kentucky. These recommendations are subject to change as new information becomes available.

The Kentucky Department for Public Health is currently requesting specimen samples for viral culture on all rapid flu tests positive for influenza A. Clinicians should also obtain a respiratory swab for viral culture on anyone who meets the following criteria:

  1. A person with acute respiratory illness who was a close contact to a confirmed case of swine influenza A (H1N1) virus infection during the case’s infectious period, OR
  2. A person with an acute respiratory illness who traveled to an area where there are confirmed cases of swine influenza A (H1N1) virus infection within 7 days of illness onset.

Close contact is defined as: within about 6 feet of an ill person who is a confirmed or suspected case of swine influenza A (H1N1) virus infection during the case’s infectious period.

Acute respiratory illness is defined as: recent onset of at least two of the following: rhinorrhea or nasal congestion, sore throat, cough (with or without fever or feverishness).

Clinicians should consider swine influenza A (H1N1) virus infection in the differential diagnosis of patients with febrile respiratory disease and who 1) live in areas in the U.S. with confirmed human cases of swine influenza A (H1N1) virus infection or 2) who traveled recently to Mexico, California, Texas, New York, Kansas, and Ohio in the 7 days preceding their illness onset..

Nancy Swikert, MD / Co-Chair Advocacy Committee / April 28, 2008 / 1-888-287-9339