One of the reasons authorities are currently worried about the possibility of a flu pandemic is the increasing amount of interaction between human flus and bird flus.
/ July 13, 2017
Imagine closed schools, overwhelmed hospitals and people dying by the thousands — or even millions. That’s the nightmare scenario for a flu pandemic.
But how likely is a pandemic to happen — and if it does, to develop into this worst-case scenario?
Pandemics are “like earthquakes: You know it’s coming, but you’re not quite sure exactly when,” said Joshy Jacob, associate professor of microbiology and immunology at Emory University. “The seasonal flu appears predictably annually. Pandemics happen unpredictably and often catch you by surprise.”
There are reasons both for alarm and for optimism, experts say. Medical research could lead to breakthroughs that would mitigate a flu pandemic. And government and private entities can make preparations to help them get through a bad pandemic if it occurs. But there is much work to be done.
People tend to hear the phrase “flu pandemic” and envision a situation like the 1918 flu, which killed millions worldwide. But a pandemic actually just means an illness that is easily spread from person to person in a susceptible population. Flu pandemics occur when the typical mutations in the influenza virus are more significant than usual — often involving viruses that affect birds.
“You get this monster virus that is half human, half bird, and when it infects you, you are totally unprepared because it has changed so drastically,” Jacob said. “When you get such big changes, that’s when you get pandemics.”
“On average, we see pandemics every 20 or 30 years or so, and they vary in terms of their intensity,” said Michelle Barron, medical director of infection prevention at the University of Colorado Hospital. There was in fact a flu pandemic in 2009, which had a devastating impact on some of those infected but ultimately did not spread as much as feared, likely because many older people had been exposed decades ago to a similar virus and had some immunity.
One of the reasons authorities are currently worried about the possibility of a flu pandemic is the increasing amount of interaction between human flus and bird flus, Barron said. A virulent bird flu is now being monitored in hopes that it will not take on the ability to spread person to person.
That doesn’t mean, however, that a repeat of the 1918 pandemic is inevitable. There are a number of differences between then and now.
“At that time, one didn’t even know that this was a virus — they thought it was bacterial,” said Peter Palese, Horace W. Goldsmith Professor and chair of the department of microbiology at the Icahn School of Medicine at Mount Sinai. “They didn’t have vaccines available, and there were no specific antiviral drugs like we have now.” The lack of antibiotics was also critical, since the virus was sometimes followed by a bacterial infection.
“In many ways, we are much better prepared than we were 100 years ago,” Palese said. “Having said that, no one can really predict what a new pandemic would look like, when it would occur and whether it would be remotely as devastating as 1918 was.”One risk factor is the increase in the
“We have many more people, and we have many more chickens than we had 100 years ago — overall, we have many more animals now living in close quarters with humans,” Palese said.
A range of scenarios
What would a pandemic mean? There is a range of possibilities.
A lot of variables go into the statistical modeling that predicts how bad an outbreak will be: How easily does the virus spread? Does it take time for symptoms to show up, so people may spread the virus before knowing they’re sick? Does it kill victims so quickly that they have no time to spread it?
“You always have to have the worst- and best-case scenarios,” Barron said. A best-case scenario might involve doctors’ offices having to open extra clinics or bring in extra staff for the emergency room. In the worst case, school systems might shut down, affecting the ability of parents to go to work.
Different organizations would face different types of challenges depending on how bad the pandemic was. If schools are ordered to close, for example, some workers would need to find people to take care of their children.
“Let’s assume 20 percent of the workforce is sick and another 20 percent are caring for people” such as children, Barron said. This poses a challenge for health care officials, who will likely need more workers during a pandemic. Where would they find replacement workers and ensure they were properly credentialed? “If day care is going to shut down, do we open our own day care? If people need to work extra shifts, who is going to let out their dogs?”
This is the type of scenario that emergency managers and others planning to handle a crisis need to think about. Plans should include supplies, such as water, antibiotics and generators, as well as people. “If people don’t have access to the things they normally need, that’s going to cause disruption,” Barron said.
In an extreme case, there could be disruptions to travel or even trash pickup.
Businesses, too, should identify the essential functions of their business and assess how they might be affected if large numbers of employees were sick or had to take care of family members. Scott Teel, vice president of marketing for Agility Recovery, which works with businesses to respond to business interruptions, recommends that businesses consider the following issues:
Businesses need to be able to communicate not only with employees and customers, but also with suppliers. “If there is a flu epidemic in your state and your employees are getting sick, what would you do on Day 1?” Teel said. “Do you know who to contact, and what the best method is to communicate your situation to customers, employees and vendors?”
Policy adjustments. Businesses may want to increase sick leave or make telecommuting possible for more employees to keep people who are sick from coming to work. They may also want to change the frequency or type of meetings to minimize face-to-face contact among employees.
Infection control. Help employees keep the virus from spreading by increasing the number of hand sanitizer or hand-washing stations, for example. It may be helpful to have more frequent office cleaning to disinfect commonly used areas. But remember, Teel said, that “there are perception issues that you’re going to face” with some of the more visible measures, such as having employees wear masks.
“If everybody in a restaurant is wearing gloves and masks, people are going to think, ‘Maybe I don’t want to eat there,’” Teel said. This is why communication planning is critical. “If you communicate in advance that you’re proactively taking this measure, people will respect that.”
Planning and prevention
Governments and medical researchers have a number of avenues for preventing or mitigating a flu pandemic:
- Surveillance. “It’s critical to have global surveillance so that as quickly as possible, one could identify a new virus that is emerging,” said Walter Orenstein, professor of medicine at Emory University School of Medicine. The surveillance efforts need to detect illness in humans and also in animals.
This surveillance must be done in cooperation with other countries. “The likelihood that the pandemic will arise in the U.S. is pretty small,” Orenstein said. “We are a global community. Surveillance has to be global. It’s critical that we invest in building and supporting surveillance capacity around the world.”
- Assessment. A good surveillance system will detect a lot of new viruses. The key to preventing or mitigating a pandemic is to focus vaccine development efforts on those most likely to become a threat. The Centers for Disease Control and Prevention uses an assessment tool that looks at factors including how easily the virus is transmitted, whether some portion of the population is already immune to it, how severe the disease is and whether there are good treatment options.
“This is used to judge the likelihood that this virus will actually emerge and be transmitted and potentially cause a severe pandemic,” Orenstein said. “For viruses that rank high in that assessment as an emerging threat, it would be important to try to develop and stockpile vaccines as an insurance policy.”
Why not just wait until it’s clear a virus is causing a pandemic? “The influenza virus spreads so fast that if you wait until the pandemic to develop the vaccine, you probably will not be able to prevent much disease,” Orenstein said. “One of the issues which government officials have to weigh is the risk of throwing money away by developing a vaccine we don’t need, versus not having a vaccine when we need it.”
This assessment should also include whether current antiviral drugs will work against this flu strain, and if so, how they can be made available if necessary.
Continued research. New and better antiviral drugs, along with a longer-lasting flu vaccine, could ultimately be the most effective protections against a pandemic.
Universal flu vaccine. The flu virus has two parts: one that changes and one that stays the same. Traditional flu vaccines target the part that changes, which is why there is a new seasonal flu vaccine each year. Pandemics develop too quickly for researchers to develop a vaccine in time to keep the virus from spreading, Jacob said.
Researchers are working, however, on a vaccine that would target the part that doesn’t change.
“We are hoping to make a vaccine that would last 10 years, 20 years,” Palese said. He emphasized that there is still a lot of work to do on this type of vaccine — and it will face intense scrutiny from the FDA since it could replace current flu vaccines, which have been shown to be safe and effective.
Flu treatment. Jacob is working on one possible treatment: peptides from frogs that could help cure flu once people get it. Better treatments could keep the flu from killing as many people and also slow its spread — possibly allowing time for a vaccine to be developed.
Those planning for a potential pandemic also have to consider various policy issues and their implications.“When the pandemic strikes, decisions need to be made about quarantines, about travel,” Orenstein said. “The problem obviously is that it can be very hard to enforce those regulations, and how effective they will be is unclear. But if there’s nothing else — if you don’t have a vaccine or drugs — then those kinds of things would be important.”
Authorities might consider closing schools. Businesses might have their employees work from home or close altogether. Hospitals, in addition to making sure they have emergency supplies of ventilators, will need plans that will minimize transmission among patients and their workers.
“Once a pandemic emerges, the major transmission is human to human,” Orenstein said. “If you can limit human-to-human contact, you may be able to limit transmission.”
Another issue: If a vaccine or antiviral drugs exist but supplies are limited, who should get them? Authorities must plan for how they would decide.
“The two factors you have to consider are who is most at risk from complications of the disease, and who are the people most likely to transmit the disease,” Orenstein said. Authorities might give top priority to health-care workers and even security forces, for example, if they were needed to maintain order. Which populations are most at risk will vary depending on the specific flu virus.
In 2009, for example, older people were more likely to have immunity, so vaccinating younger people was a higher priority. Most seasonal flu viruses, on the other hand, are a greater danger for the elderly.
“Pandemics are not all the same,” Orenstein said.