Flu vaccine beginning to arrive as physicians brace for season

Last fall, patients ill with the influenza A(H1N1) virus filled doctors' waiting rooms across the country. Manufacturing delays, due in part to antiquated technology, left many physicians with limited or no H1N1 vaccine when the virus peaked. When immunizations did arrive, many patients no longer were interested in getting the shots.

Though experts hesitate to predict the severity of the upcoming influenza season, they do not expect the magnitude of problems of 2009. The flu vaccine for the 2010-11 season has started arriving in physicians' offices.

Adding the H1N1 virus to the seasonal flu vaccine and using standard immunization distribution procedures also are expected to simplify the flu season.

"The manufacturers are telling us they're going to be producing abundant supplies of vaccines, so there is no need for providers to hold onto vaccines. They should use them as they get them," said Tom Skinner, spokesman for the Centers for Disease Control and Prevention.

Meanwhile, Dr. Margaret Chan, director-general of the World Health Organization, said on Aug. 10 that the H1N1 pandemic is over. "The new H1N1 virus has largely run its course," she said.

As many as 40 million monovalent 2009 H1N1 doses expired as of June 30, due largely to manufacturing delays that left physicians with a surplus of vaccine after cases of the virus already had waned. Millions more doses languished in doctors' practice refrigerators. Experts do not anticipate such large numbers of flu shots going unused this season.

By late July, manufacturers began shipping the vaccine to health care professionals. Five manufacturers are supplying the influenza vaccine to the U.S. this year. Projections show about 170 million seasonal flu vaccine doses will be produced.

The vaccine will be distributed following the standard procedure for seasonal flu shots, meaning it will be shipped directly to distributors, who will supply them to doctors. Doses will not be allocated by the federal government, as the 2009 H1N1 vaccine doses were.

Vaccine makeup

The 2010-11 seasonal vaccine will include a pandemic 2009 H1N1 virus, as well as an A/Perth/16/2009 (H3N2)-like virus and a B/Brisbane/60/2008-like virus. Adding an H1N1 strain to the seasonal vaccine should make this flu season easier for physicians than last year, said Robert A. Salata, MD, chief of the Division of Infectious Diseases and HIV Medicine at University Hospitals Case Medical Center in Cleveland.

"We don't have to deal with two separate vaccines. ...[And] we don't have to deal with all the hurdles for getting the vaccine," he said.

The typical flu season goes from October through April, but experts say transmission of the virus could begin and end at any time. Skinner encouraged physicians to vaccinate all patients, rather than reserving flu shots for those at highest risk of flu-related complications, including the elderly and young children.

Patients who are vaccinated in August or early September will still be protected by the spring from this season's flu, Skinner said. The vaccine "provides immunity for six to eight months," he said.

Although there has been no substantial H1N1 and seasonal flu activity this summer, the CDC issued an advisory to health professionals on Aug. 4, alerting them to an uptick in cases of the influenza A(H3N2) virus. The report stated that H3N2 infections were detected in several states, including two small localized outbreaks in Iowa, between late-June and July. A strain of the virus is included in this season's flu vaccine.

"Every year we have influenza cases in the summer. ... [These reports of illness] are something to keep on the radar screen. But it's certainly no reason to panic, because these numbers have been very small," said Annette C. Reboli, MD, head of the Division of Infectious Diseases at Cooper University Hospital in Camden, N.J.

The CDC urged physicians to consider influenza as a possible diagnosis when evaluating patients with acute respiratory illness. Doctors are encouraged to use antivirals oseltamivir (Tamiflu) and zanamivir (Relenza) to treat the flu virus. Physicians should not use the antivirals amantadine and rimantadine because of high levels of resistance to these drugs among recently circulating influenza viruses, the CDC said.

Getting ready

Some doctors are stocking up on face masks and hand sanitizers to prepare for the upcoming flu season. Others are educating their staffs and patients on the federal government's new vaccine recommendations.

However, there is a sense of uncertainty in the medical community about what to expect this year and how to prepare for it.

"I think there will be less susceptible people [to H1N1] this year. But will this be overcome by a more aggressive strain or by other influenza strains? That might be the case," Dr. Salata said.

Before physicians receive vaccine doses, Dr. Reboli recommends that they post signs in waiting rooms encouraging patients with flu-like illness to cough or sneeze into their arms to prevent spreading the virus.

When the vaccine arrives, the first doses should be administered to health professionals, said William Schaffner, MD, an infectious disease specialist at Vanderbilt University School of Medicine in Nashville, Tenn. After staff is immunized, doctors can begin vaccinating patients, he said.

During the 2009-10 season, the CDC found vaccination rates among health professionals to be higher by mid-January for the seasonal flu (61.9%) than for H1N1 (37.1%).

"It's really unconscionable that health care professionals could be sick [with the flu] and make their patients sick. ... To prevent that possibility, all health care workers need to get vaccinated," said Julie Boom, MD, MPH, director of infant and childhood immunization at the Center for Vaccine Awareness and Research at Texas Children's Hospital in Houston.

She encourages doctors who receive the flu vaccine in August to use back-to-school physicals as a chance to vaccinate patients, including college students.

The CDC Advisory Committee on Immunization Practices recommends that everyone 6 months and older be vaccinated against influenza. Previous vaccine guidelines applied to about 85% of the population but did not include healthy people 19 to 49 unless they had close contact with others considered at high risk for the flu, according to the CDC.

On Aug. 5, the ACIP issued another recommendation, this one advising health professionals not to administer CSL Biotherapies' flu vaccine Afluria to children 6 months through 8 years due to risks of febrile seizure. The committee said the immunization could be used in children older than 5 years if they have a high risk of flu-related complications and no other vaccine is available.

In Australia, Afluria has been associated with an increased incidence of fever and seizure among children, particularly those younger than 5, the Food and Drug Administration said.

Investigations into the cause of the adverse events are ongoing, said CSL spokeswoman Sharon McHale. "Given that we haven't been able to establish a cause, CSL supports the precautionary approach taken by the ACIP," she said.

Dr. Schaffner, of Vanderbilt, said the Afluria recommendation could cause some challenges for pediatricians and family physicians who will need to immunize young children with a different influenza vaccine.

"We hope that is the only bump in the road with this year's influenza vaccine program," he said.