CDC's Advisory Committee Gives Thumbs-up to New Antiviral Recs

Members of the CDC's Advisory Committee on Immunization Practices, or ACIP, approved new antiviral treatment recommendations during the committee's June 24-26 meeting in Atlanta. The recommendations originally were released as interim guidance last year in the wake of oseltamivir resistance among circulating seasonal influenza A (H1N1) viruses.

The recommendations call for use of

According to the CDC, all currently circulating influenza viruses, including novel influenza A (H1N1), are sensitive to zanamivir.

During a June 26 media briefing after the ACIP meeting concluded, Anne Schuchat, M.D., director of the CDC's National Center for Immunization and Respiratory Diseases, or NCIRD, recapped some of the updates on the novel H1N1 virus that committee members heard at the meeting. Specifically, she said, the CDC now estimates that at least 1 million Americans have been infected with the novel H1N1 virus.

The CDC estimate was derived from population-based surveys in areas that have reported incidences of influenza-like-illness to be 6 percent or higher, Schuchat explained. She acknowledged that the estimate was based on preliminary figures using incomplete modeling, and pointed out that the novel H1N1 virus currently accounts for more than 99 percent of all influenza A viruses subtyped in the United States. Therefore, she said, the actual numbers could well go higher.

Schuchat reiterated that pregnant women and people with underlying conditions, such as asthma, diabetes, and heart or lung disease, should contact their physicians if they have flu-like symptoms. Three-fourths of the 127 U.S. fatalities reported as of June 26 have involved people with underlying conditions.

Schuchat also advised physicians to focus their use of antiviral medications on people in those high-risk groups, as well as the elderly and young children. Although the majority of cases and hospitalizations are in younger patients, she said, when people 65 and older contract the novel H1N1 virus, their chance of dying is greater.

Five vaccine manufacturers are working to develop a vaccine for the novel H1N1 virus, but Schuchat said no decision has been made to go forward with a national immunization program for the pandemic flu. The vaccine still must be tested and approved by FDA.

Even so, Schuchat urged state and local health departments to start planning now for how they will offer and administer the vaccine if and when it becomes available. The CDC is developing planning materials to help in that regard, she said.

CDC officials told ACIP members during the meeting that the agency is confident that vaccine -- possibly as much as 60 million doses -- will be available by October.

According to Doug Campos-Outcalt, M.D., M.P.A., the AAFP's liaison to the ACIP and associate head of the department of family and community medicine at the University of Arizona College of Medicine, Phoenix, 60 million doses by October probably represents a best-case scenario. Given that the H1N1 vaccine may well require two doses, administration most likely will be prioritized, he said.

Campos-Outcalt pointed out that HHS' current pandemic flu plan calls for workers critical to maintaining the nation's infrastructure during a pandemic, such as firefighters, police, first responders and health care workers, to be prioritized for vaccination.

However, he said, that plan was based on the assumption that expected mortality would be high during a pandemic. If H1N1 remains relatively mild, prioritization could change to put people in high-risk groups at the top of the list.

So, what role can family physicians expect to play in delivering the H1N1 vaccine?

"That's a good question," Campos-Outcalt said, "and there were no answers. It's going to be sent to the states, and there's going to be a lot of state discretion." He added that there is a good chance ACIP members will meet again before their scheduled October session to work on recommendations for the new vaccine.

"The message for family physicians is that there are a lot of unknowns, and everyone needs to stay alert," he said. "The AAFP will keep physicians up-to-date as much as possible, but they should stay in contact with their state and local health departments, as well. Physicians' offices may or may not be involved in pandemic flu vaccinations. That hasn't been decided yet."