Photo by AlphaTangoBravo/Adam Baker, via Flickr.

Photo by AlphaTangoBravo/Adam Baker, via Flickr.

The following comes to us from the Centers for Disease Control and Prevention (CDC):

 

Swine Flu Guidance for Clinicians & Public Health Professionals

[as of April 29, 2009, 1:45 AM ET] http://www.cdc.gov/swineflu/guidance/
Clinicians should consider the possibility of swine influenza virus infections in patients presenting with febrile respiratory illness. If swine flu is suspected, clinicians should obtain a respiratory swab for swine influenza testing and place it in a refrigerator (not a freezer). Once collected, the clinician should contact their state or local health department to facilitate transport and timely diagnosis at a state public health laboratory.

Interim Guidance for Clinicians on Identifying and Caring for Patients with Swine-origin Influenza A (H1N1) Virus Infection [as of April 29, 2009 2:00 AM ET] http://www.cdc.gov/swineflu/identifyingpatients.htm
Interim guidance is provided here for nurses and clinicians who might provide care for patients with swine-origin influenza A (H1N1) or suspected swine-origin influenza A (H1N1) virus infection. It will be periodically updated as information becomes available.

Transmission
Transmission of swine-origin influenza A (H1N1) is being studied as part of the ongoing outbreak investigation, but limited data available indicate that this virus is transmitted in ways similar to other influenza viruses. Seasonal human influenza viruses are spread from person to person primarily through large-particle respiratory droplet transmission (e.g., when an infected person coughs or sneezes near a susceptible person). Transmission via large-particle droplets requires close contact between source and recipient persons, because droplets do not remain suspended in the air and generally travel only a short distance (<1 meter) through the air. Contact with respiratory-droplet contaminated surfaces is another possible source of transmission. Because data from swine-origin influenza viruses are limited, the potential for ocular, conjunctival, or gastrointestinal infection is unknown. Since this is a novel influenza A virus in humans, transmission from infected persons to close contacts might be common. All respiratory secretions and bodily fluids (diarrheal stool) of swine-origin influenza A (H1N1) cases should be considered potentially infectious.

Incubation period
The estimated incubation period is unknown and could range from 1-7 days, and more likely 1-4 days.

Persons with confirmed Swine-origin influenza A (H1N1) virus infection
Nurses should suspect swine-origin influenza A (H1N1) in persons with an acute febrile respiratory illness who

• Have had close contact with a person who is a swine-origin influenza confirmed case or

• Traveled to a community in the United States or internationally where there are one or more confirmed swine-origin influenza cases (Updated information about areas with confirmed human cases of swine-origin influenza A (H1N1) can be found at http://www.cdc.gov/swineflu/investigation.htm.) or

• Reside in a community where there are one or more confirmed swine-origin influenza A (H1N1) cases.

Clinical findings
Patients with uncomplicated disease due to confirmed swine-origin influenza A (H1N1) virus infection have experienced fever, headache, upper respiratory tract symptoms (cough, sore throat, rhinorrhea), myalgia, fatigue, vomiting, or diarrhea.

Groups at high risk for complications
There are insufficient data available at this point to determine who is at higher risk for complications of swine-origin influenza A (H1N1) virus infection. At this time, the same age and risk groups who are at higher risk for seasonal influenza complications should also be considered at higher risk for swine-origin influenza complications .

High risk groups for seasonal influenza complications include: infants aged 12–24 months; HIV-infected persons; adults aged >65 years, residents of any age of nursing homes or other long-term care institutions; and persons with asthma or other chronic pulmonary diseases, such as cystic fibrosis in children or chronic obstructive pulmonary disease in adults, hemodynamically significant cardiac disease, immunosuppressive disorders or who are receiving immunosuppressive drugs, sickle cell anemia and other hemoglobinopathies, diseases that requiring long-term aspirin therapy, such as rheumatoid arthritis or Kawasaki disease, chronic renal dysfunction, cancer, chronic metabolic disease, such as diabetes mellitus, neuromuscular disorders, seizure disorders, or cognitive dysfunction that may compromise the handling of respiratory secretions.

Reporting suspect swine-origin influenza A (H1N1) virus infection

Nurses and other clinicians should contact their state public health department to report suspected cases of swine-origin influenza A (H1N1) virus infection and to obtain information on what clinical and epidemiological data to collect and specimen shipment protocols in their state.

Testing for swine-origin influenza A (H1N1) virus
Clinicians should consider testing suspected cases of swine-origin influenza A (H1N1), especially those with severe illness, by obtaining upper respiratory specimens, such as a nasopharyngeal swab or wash, or nasal wash/aspirate, or tracheal aspirate, to test for swine-origin influenza A (H1N1) virus. Specimens should be tested by the state public health laboratory. Interim guidance on specimen collection ,processing, and testing for patients with suspected swine-origin influenza A (H1N1) virus infection can be found at: http://www.cdc.gov/swineflu/specimencollection.htm

Treatment for swine-origin influenza A (H1N1)
The swine-origin influenza virus is susceptible to both oseltamivir and zanamivir. It is resistant to amantadine and rimantadine. Interim guidance on antiviral treatment for swine-origin influenza A (H1N1) can be found at: http://www.cdc.gov/swineflu/recommendations.htm

Infectious period
The duration of shedding with swine-origin influenza A (H1N1) virus is unknown. Therefore, until data are available, the estimated duration of viral shedding is based upon seasonal influenza virus infection. Infected persons are assumed to be shedding virus from the day prior to illness onset until resolution of symptoms. Persons with swine-origin influenza A (H1N1) virus infection should be considered potentially contagious for up to 7 days following illness onset. Persons who continue to be ill longer than 7 days after illness onset should be considered potentially contagious until symptoms have resolved. Children, especially younger children, might be contagious for longer periods.

For more information, visit http://www.cdc.gov/swineflu/guidance/.