Issue: December 2019
December 20, 2019
10 min read

Bad flu seasons test US hospitals

Issue: December 2019
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Hospitals in the United States implemented new policies based on the severe 2017-2018 influenza season, but experts agree that America’s health care systems would still be seriously challenged by another bad season.

According to interviews, tight resources and underfunding mean hospitals are ill prepared for “surge” events like the 2017-2018 season — the first to be classified as “high severity” across all age groups. An estimated 959,000 people were hospitalized, and 79,400 people died because of influenza that season, including 187 documented pediatric deaths. The number of cases of influenza-associated illness — an estimated 48.4 million people — was the highest since the 2009 H1N1 pandemic, when an estimated 60 million people became sick with influenza.

Last season was comparatively milder, but still included 143 influenza-related pediatric deaths and an estimated 36,000 to 61,000 overall deaths. It was the longest influenza season in 10 years. Early indicators for this season showed an unusual pattern: as of mid-November, influenza B viruses predominated, rather than A viruses. The CDC reported four influenza-related pediatric deaths in the first weeks of the season.

Paul D. Biddinger, MD, director of the Center for Disaster Medicine at Massachusetts General Hospital, said the severity of the 2017-2018 influenza season reinforced the need to recommend vaccination to patients. “If the flu season were much worse,” he said, “hospitals could easily be pushed beyond their capacity.”

Source: MGH Photography Department

William Schaffner, MD, professor of preventive medicine at Vanderbilt University Medical Center and medical director of the National Foundation for Infectious Diseases, said hospital capacity across the country was “stretched but not broken” during the 2017-2018 season, and most hospitals were able to manage because they had a pandemic preparedness plan in place.

“That plan probably was, at least in its early stages, put into operation [that] year in many hospitals,” he told Infectious Diseases in Children.

Among other plans of action, notice went out to medical providers that patients needed to be discharged as promptly as medically appropriate to make sure there were enough beds available to accommodate the influx of patients with influenza, Schaffner said. The CDC noted that the estimated number of hospitalizations during the 2017-2018 influenza season exceeded the number of staffed hospital beds in the United States — 902,202.

Other experts agreed with Schaffner’s assessment that hospital staff and preparedness levels have been stretched to the limit. They said hospitals may not be prepared for an influenza pandemic.

William Schaffner

“You cannot be perfectly prepared for any large pandemic, whether flu or otherwise,” Schaffner said. “Our nation is tight on hospital beds. Intensive care unit facilities are finite, ventilators are finite, the staff that is knowledgeable about managing patients on ventilators is finite, so if we were to be hit in the United States and around the world with a major new pandemic influenza virus, I think our medical care facilities would be very, very challenged.”

‘Surge capacity’ a challenge

According to Michael T. Osterholm, PhD, MPH, professor and director of the Center for Infectious Disease Research and Policy at the University of Minnesota, hospital capacity is a concern not just in severe influenza seasons, but during any major health care crisis.

“Very few institutions anywhere in the country have surge capacity, meaning unused capacity just sitting there waiting for a crisis to happen,” Osterholm told Infectious Diseases in Children. “It would be like a manufacturing plant overbuilding its manufacturing capacity so that once a year when they get a potential increase in order numbers, they can use that capacity. That just doesn’t make sense for them, financially. It is the same thing with health care. We worry all the time about the need for surge capacity.”

The 2017-2018 influenza season “brought preparedness issues to the surface,” he said.

“We are constantly dealing with shortages and a limited capacity to respond to a surge situation, and that’s the reality of health care today. Flu is probably the one thing out of all the diseases we deal with that challenges that surge capacity issue, short of a localized crisis, like terrorism or a mass shooting. Flu is in some ways the disease that is a barometer that tells us how capable we are.

“When you hear about patients being in the hallways and not having room for them, that really is not necessarily a function of the flu season, it is a function that we just hit capacity.”

According to Paul D. Biddinger, MD, director of the Center for Disaster Medicine at Massachusetts General Hospital (MGH), surge capacity for severe infectious disease outbreaks is even more constrained for pediatrics than it is for adults, with only a small portion of hospital capacity dedicated to children “because their usual rate of illness is typically much lower than older adults,” he said.

“In a severe flu pandemic, however, where children may be affected at rates similar to adults, these rare pediatric inpatient resources can easily become overwhelmed,” Biddinger told Infectious Diseases in Children. “Pediatric wards are typically straining for capacity in a typical winter season, and a severe flu season could push that to the breaking point.”


Biddinger noted that the “attack rate” for influenza is twice as high among children than it is for adults aged 65 years or older.

Federal funding cuts to blame

Federal funding cuts to hospitals and the public health system are a major reason for the lack of surge capacity, Jeffrey S. Duchin, MD, health officer and chief of the communicable disease epidemiology and immunization section for the Seattle and King County, Washington, public health department and a professor of medicine in the division of infectious diseases at the University of Washington, told Infectious Diseases in Children.

“Our hospitals are struggling with the ability to meet medical surge events, even in the absence of a severe flu season,” Duchin said. “Even before flu season in the Puget Sound region, we have experienced EMS diversion, long ED wait times, caring for patients in untraditional spaces, like hallways, and having higher than usual patient-to-staffing rates. What this tells us is that there is a clear need for health care systems to better operationalize medical surge strategies. Hospitals have lost a lot of funding, as have public health departments related to emergency preparedness.”

For example, Duchin noted that the Hospital Preparedness Program (HPP) — the only federal source of funding for hospital preparedness — has been more than halved since 2003. HPP appropriations were cut from $514 million in fiscal year 2003 to $255 million in fiscal year 2017, according to the nonprofit Trust for America’s Health.

“The bottom line is we do not have an adequate source of steady funding for hospital or public health preparedness, and the result of that is that hospitals struggle with even moderate surge events, so a severe flu season could be very challenging for many of our health care facilities,” Duchin said. “This is really any type of emergency — a bioterrorist attack, a train derailment, an infrastructure catastrophe, such as a bridge accident, flood, landslides, which would include lots of injuries with people requiring hospital care.”

Mandatory staff vaccinations

Hospitals may not be completely prepared for a bad influenza season, but one thing that can lessen the burden is for more people to get vaccinated. That includes health care workers.

“More hospitals are introducing mandatory influenza vaccination programs for their staff, which improves preparedness and decreases transmission, and that is an improvement,” Biddinger said. “It’s pretty clearly documented that the higher vaccination rates decrease transmission of influenza, and of course, the vaccine isn’t perfect, but it is an important step. I think that hospitals really do appreciate the importance of preparedness for flu season, and hospitals, including my own, have recently taken bigger steps, such as mandatory employee vaccination.”

Jeffrey S. Duchin

Biddinger said the campaign to move to mandatory vaccination predated the 2017-2018 influenza season. But the severity of that season reinforced the need to recommend vaccination to patients.

“I think it has made it easier for primary care physicians and others to have conversations with their patients about the importance of flu vaccinations,” he said. “Numbers like 80,000 deaths are heartbreaking, but they are also motivational for some patients to understand why they need the vaccine, and it is helpful for providers to explain why they are recommending vaccination for everyone.”

Biddinger said there are still myths about the influenza vaccine — such as patients getting influenza from the vaccine, or that healthy people do not need the vaccine — and sometimes patients will respond to recommendations when there are large numbers of illnesses, like there were two seasons ago.

“You can get people to understand that if you are healthy, you are less likely to get the flu just by getting the vaccine, and if you get sick, you are less likely to die if you have received the vaccine. Those are very important messages,” he said.

According to the CDC, young children, older adults and pregnant women are most likely to experience severe influenza-related complications that can lead to hospitalization. Studies have shown that vaccination reduces the risk for influenza-related pediatric deaths by 65% among healthy children and 51% among children with high-risk medical conditions, and halves the risk for influenza-related hospitalization in adults.

“The other key point is that many people forget is that there are antiviral drugs available that are critical in helping people who have underlying high-risk conditions to avoid severe illness,” Duchin said. “That could be hospitalization. It could be intensive care unit. It could be death.”

Infectious Diseases Society of America practice guidelines published last December emphasized the need to test and promptly treat patients at high risk for seasonal influenza-related complications, including young children, pregnant women, patients who are extremely obese and those who have a weakened immune system. The guidelines recommended antiviral treatment in patients if they are sick enough to be hospitalized with influenza symptoms, and that antivirals should be prescribed to patients at high risk for influenza-related complications even if they have been sick for more than 2 days.

“Antiviral drugs can do a lot to relieve the stress on health care systems if they are used appropriately in the outpatient population,” Duchin said. “Fewer people will require ED visits and hospitalizations.”


He added that “early antiviral treatment is most effective in preventing serious illness and produces the most benefit. For patients hospitalized with influenza, antiviral treatment should be initiated even if beyond the optimal initiation period.”

One of the main strategies for dealing with the health care overload “is to treat people as outpatients, and that means you have to treat them early with antiviral drugs before they get sick enough to need hospitalization,” Duchin said.

In October 2018, the FDA approved Xofluza (baloxavir marboxil, Genentech) — the first new influenza treatment in nearly 20 years — for the treatment of uncomplicated influenza in patients aged 12 years or older who have been symptomatic for up to 48 hours. This past October, the FDA expanded the approval to include patients aged 12 years or older who are at high risk for influenza-related complications and have been symptomatic for no more than 2 days.

In July, Genentech announced results of a phase 3 study that showed one dose of baloxavir marboxil was well-tolerated and demonstrated comparable efficacy to oseltamivir in children aged 1 to 12 years, and that a separate global phase 3 trial was underway to assess the safety and efficacy of the treatment in children aged younger than 1 year.

An ‘unusual’ start

The proportion of outpatient visits attributed to influenza-like illness climbed above the national baseline for the first time this season in mid- November, comprising 2.5% of visits during the week ending Nov. 16, according to CDC FluView data.

Of note, more than half of influenza-positive samples tested at public health laboratories were influenza B viruses. In the week ending Nov. 16, 63.9% of positive specimens were influenza B viruses.

According to Bernhard L. “Bud” Wiedermann, MD, MA, attending physician in infectious diseases at Children’s National Hospital in Washington, D.C., and professor of pediatrics at The George Washington University School of Medicine & Health Sciences, the early predomination of influenza B is “unusual” in the United States.

Bernhard L. “Bud” Wiedermann

“Generally, we see it toward the tail end of the season,” he told Infectious Diseases in Children. “At present, it is just an anomaly but could mean that we are going to see another peak of influenza A later in the flu season.”

The overall hospitalization rate due to influenza was 1.4 per 100,000 people during the week ending Nov. 16, typical for that time of year, the CDC said. Pneumonia and influenza caused 5.2% of deaths, still below the 6.2% epidemic threshold.

Among 158,740 samples tested in clinical laboratories, 3.3% were positive for influenza — 31.7% for influenza A and 68.3% for influenza B. In public health laboratories, of 8,105 specimens tested, 1,676 were positive. Influenza A comprised 48.4% of samples and influenza B comprised 51.6%.

Wiedermann noted that these trends should not affect treatment — “We don’t need to treat influenza B any differently from influenza A. Medications that treat influenza are generally active against both strains” — but he said vaccine efficacy may be impacted, particularly for older patients.

According to Wiedermann, CDC data going back 15 years do not show evidence of an influenza B–predominant season.

“It’s just a sign to be on the lookout for an atypical year,” he said. – by Bruce Thiel, Gerard Gallagher and Marley Ghizzone


Disclosures: Schaffner reports serving on the data safety monitoring committees on behalf of Merck and Pfizer and serving as an occasional consultant for Dynavax, Sutrovax and Shionogi. Biddinger, Duchin, Osterholm and Wiedermann report no relevant financial disclosures.

Click here to read the Point/Counter “Should physicians prescribe antivirals to patients at high risk for flu-related complications more than 2 days after symptom onset?”