Employee health professionals brace for waves of flu, long vaccine campaigns

Novel H1N1 vaccine expected by mid-October

Be prepared for a double strike of influenza this year - and a prolonged season of vaccination to combat it. Flu experts are bracing for a new wave of the novel H1N1 influenza A strain that could strike early in the fall, as well as the usual pattern of seasonal influenza in the winter. That could mean a surge of patients while hospitals cope with greater absenteeism among health care staff. At a national H1N1 summit, U.S. Secretary of Health and Human Services Kathleen Sebelius called on states and health care providers to be ready to vaccinate as a key method to prevent transmission.

"We absolutely can't afford to be unprepared. If we look at the public health history, vaccination programs are one of the great public health success stories," she said.

Supplies of seasonal influenza vaccine will be abundant this year, with an estimated 199 million doses by the end of October. The first doses, about 51 million, are slated for delivery by the end of August. Hospitals should immediately begin vaccinating when they receive their first doses and continue vaccinating throughout the fall and winter, says Anthony Fiore, MD, MPH, medical epidemiologist and infectious disease specialist with the Centers for Disease Control and Prevention influenza division.

"For the past several years, we've advocated extending the time when people should get vaccinated [both earlier and later]," he reports.

Testing of the H1N1 vaccine continued throughout the summer, and by mid-October, tens of millions of doses may be available, Fiore says. Vaccine experts still were unsure about whether adjuvants could be used to extend the vaccine supply or improve its effectiveness, and problems with vaccine yield could cause production delays.

Health care workers will be among the priority groups receiving the vaccine, which may require two doses. In fact, the World Health Organization announced that health care workers should be the first to receive the vaccine because they are critical to maintaining functioning health systems.

Set priorities for vaccination

With an urgency to vaccinate health care workers against both seasonal and pandemic influenza, employee health professionals face unique logistical challenges. It's also unclear how health care workers will view flu vaccination this season. Will they want to be vaccinated against the novel strain because of the media coverage of the pandemic? Will they erroneously think that the seasonal vaccine is less important?

Hospitals were gearing up their flu vaccine marketing campaigns with extra education on H1N1.The Joint Commission, the accrediting body based in Oakbrook Terrace, IL, issued a monograph to provide detailed strategies and a review of research for health care facilities in an effort to boost seasonal influenza vaccination rates.

"[Seasonal influenza] threatens to get lost with all the attention to H1N1," says William Schaffner, MD, an infectious disease expert and professor and chairman of the Department of Preventive Medicine at Vanderbilt University in Nashville, TN. Employee health professionals should shift their campaigns as early as possible, he says. "You want to clear the decks because you're going to have to do it over again with H1N1, in all likelihood."

CDC is not likely to issue detailed recommendations on which health care workers involved in direct patient care should receive the vaccine first - such as those in the emergency department or intensive care unit. In 2004, when there was a shortage of seasonal vaccine, "people were so concerned about the needs of others who might need to vaccine more to be at the front of the line that no one went to the front of the line," says Fiore, and vaccine was actually unused.

Yet individual hospitals need to plan for novel H1N1 vaccination with subpriorities, advises Schaffner. "If we only get 400 doses at Vanderbilt - and we have 5,000 employees - who are those 400 people going to be? You would do well to think in that kind of staged fashion," he says.

Another important consideration: Health care workers who are pregnant or have other underlying risk factors, such as asthma or diabetes.

Severe disease and fatalities have occurred among pregnant women with the novel H1N1, Anne Schuchat, MD, CDC's director of the National Center for Immunization and Respiratory Diseases, told reporters at a press briefing. CDC will be urging pregnant women to get both seasonal and novel H1N1 vaccines. "We're urging women who are pregnant who develop fever or respiratory symptoms to seek care promptly. We think that early antiviral medicines for these women are really important," she said.

Employee health professionals may want to make sure that employees who are at greater risk of complications from influenza get the pneumococcal disease, a one-time dose for people younger than 65. Pneumococcal vaccine is recommended for smokers and anyone with asthma, heart or lung disease, or people with lowered immunity, such as those with cancer, organ transplants, kidney failure, or HIV/AIDS.

CDC decided against recommending the pneumococcal vaccine for all health care workers. "The epidemiology of the pandemic right now does not suggest that health care workers are at any increased risk of pneumococcal infection, and there's not any evidence that among those health care workers who have developed H1N1 that they have an increased risk of bacterial complications," says Matthew Moore, MD, MPH, medical epidemiologist with CDC's Division of Bacterial Diseases.

Flu is unpredictable

One thing is clear about the influenza virus: It is unpredictable. That means employee health professionals must remain flexible in their planning.

"There's a one-hundredfold difference in documented infections in different states. What one community experiences is not necessarily what another community, even nearby, is experiencing," CDC director Thomas Frieden, MD, MPH, told the H1N1 summit.

In the Southern Hemisphere, H1N1 has spread alongside seasonal influenza, and in the United States, transmission of H1N1 continued throughout the summer. As of late July, there was no evidence that the seasonal and novel strains had blended or that the novel H1N1 had mutated significantly. So far, it remains susceptible to Tamiflu and Relenza, the major antiviral medications.

"H1N1 is uncertain. It's going to remain uncertain until we have more information about the disease and vaccine," cautions L.J. Tan, MS, PhD, director of Medicine and Public Health for the American Medical Association in Chicago. "Don't be immobilized by the uncertainty around the pandemic such that you don't execute the seasonal plan."

It's also still possible that the novel H1N1 could become a more virulent strain, flu experts cautioned. Researchers from the University of Wisconsin-Madison and Japan found that the novel H1N1 caused more lung damage and replicated more efficiently in the trachea and lower respiratory tract than does seasonal influenza in animal tests. The researchers tested H1N1 and seasonal strains in macaques, mice, miniature pigs, and ferrets. It's not clear how well animal models predict disease patterns in humans.1

The researchers also found that the virus remains susceptible to the common antiviral medications, Tamiflu and Relenza.

Meanwhile, flu experts say the virus has spread more quickly than previous pandemics. "We have seen this virus reach nearly every country in a matter of weeks and months rather than years," Schuchat said.

"We don't know the extent of the challenges that we'll face in the weeks and months ahead," she said. "We do know that there's a lot we all can do to be as ready as possible to face those challenges."

(Editor's note: Up-to-date information on influenza vaccine availability can be found through the Influenza Vaccine Availability Tracking System at www.preventinfluenza.org/ivats/.)

Reference

1. Itoh Y, Shinya K, Kiso M, et al. In vitro and in vivo characterization of new swine-origin H1N1 influenza viruses. Nature. Online publication on July 13, 2009. Accessed on July 21, 2009; www.nature.com/nature/journal/vnfv/ncurrent/abs/nature08260.