Influenza A (H1N1) "Swine Flu:" What EMS Providers Should Know

Earlier this week, the World Health Organization raised the Pandemic Alert Level to Phase 4, sending the world's media and medical communities into a frenzy of worry and action. Phase 4 alerts are issued whenever human to human transmission is confirmed for an animal or human-animal influenza or virus, and the transmission is suspected of being capable of causing "community level outbreaks." With 100 confirmed U.S. cases - including 1 death - in several states and communities (as of the writing of this article) the implications for EMS providers cannot be overlooked.

Editor's Note: Since the writing of this article on April 29, the WHO has raised the worldwide pandemic alert level to Phase 5, indicating a "strong signal that a pandemic is imminent and that the time to finalize the organization, communication, and implementation of the planned mitigation measures is short." The CDC reported a total of 109 confirmed cases and one death as of April 30. For updates visit cdc.gov/swineflu.

In addition, this "Swine Flu" is not the same Swine Flu that has broken out several times in the past, although the viruses are being compared in the media. This new virus, which also incorporates human and avian virus elements, is now officially and more appropriately known as influenza A (H1N1).

Symptoms of an H1N1 infection are identical to that of influenza. The symptoms include lethargy, high fever (greater than 102°F), weakness, sore throat, runny nose, coughing, loss of appetite, nausea, and vomiting. In severe cases, patients can develop shortness of breath progressing to respiratory distress, dehydration, cyanosis, mental status changes, and severe anxiety and agitation.

Influenza A (H1N1), like other influenza viruses, is airborne and can be spread through direct contact as well. Close proximity with infected swine or individuals can cause transmission. Typically human-to-human transmissions occur when an infected individual coughs or sneezes, or when an infected individual touches something (rails of a cot) with the virus and then another individual touches the same surface before it is cleaned. Airborne transmission often occurs when individuals are within "close contact," which O.S.H.A. defines as 6 feet, but the World Health Organization defines as 1 meter - just over 3 feet. Once infected, the incubation period is as short as 24 hours, or up to a week depending on the source.

As fear over influenza A (H1N1) sweeps through the country, there may be a surge in 911 calls for high fever, shortness of breath, and weakness. EMS is the front line of the health care system, and it is critical that we do our part to help prevent inadvertent virus spread.

Be alert, but not paranoid. Maintain a high index of suspicion any time an ambulance is requested for fever or any flu like signs and symptoms. While evaluating patients, ask about recent travel as a part of their medical history. Suspect a potential influenza A (H1N1) infection any time a patient has flu-like symptoms and they, or someone close to them, has traveled to an area with a confirmed virus outbreak. Currently, there is an outbreak in Mexico, and many cases have been diagnosed in New York City. Cases have also been confirmed in California, Kansas, Ohio, Texas, Canada, New Zealand, Israel, Spain and the United Kingdom. (See updates at cdc.gov/swineflu).

Most patients with intact immune systems will fully recover from the virus. Pediatric patients with immature immune systems, individuals on immunosuppressant drugs, and elderly patients with weakened immune systems are at an increased risk for developing more serious symptoms, just as they are with other influenza viruses. Additionally, people living in close quarters such as college dorms, jails, skilled nursing facilities, and homeless shelters risk having multiple people become exposed during the virus's incubation period.