In 2009, THE H1N1 influenza pandemic claimed more than 14,000 people worldwide. This outbreak was still relatively mild, with a mortality rate of about one in 10,000 people who developed the disease. However, scientists and health officials agree - the question we need to ask is when, and not if, the next influenza pandemic will strike.
Researchers are hard at work looking for what type of virus might become the next pandemic, where it most likely will emerge and who its most likely victims will be.
Pandemic vs. Seasonal Flu
The basic dynamics of how these diseases are spread are still being researched. And because small mutations can alter how they spread and their virulence dramatically, our knowledge of these deadly flu strains is constantly changing. A single mutation, for example, can make a flu strain resistant to approved antiviral medications like Tamiflu.
One of the scariest things about influenza pandemics when compared to the seasonal flu is that they have a tendency to sicken and kill the young and seemingly healthy, who would otherwise fall into a low-risk category for seasonal flu. Some researchers have linked underlying risk factors, including heart disease and neurological conditions, with higher fatality rates. For example, a survey of global data following the H1N1 pandemic found that chronic conditions were reported among more than 40 percent of people who were hospitalized for the flu and later died.
Because there is such a dramatic difference in how one person will react to a flu virus, even compared to someone else in the same household, researchers are looking at what makes one healthy adult able to fight off the disease at home, while another ends up hospitalized.
Research in this field is extensive and wide-reaching. Experts are looking at everything from human and viral genetics to potential involvement of bacterial infections and elsewhere for clues as to why some people face serious complications from this virus, seemingly at random.
Preparing for the Unknown
In 2009, research models predicted that a Southeast Asia-based strain of flu, such as the 2003 SARS outbreak, would take two to four months to spread within the area and that it would arrive in Europe and North America about a month after that, giving Western countries three to seven months to develop treatment plans and vaccination options.
Instead, the H1N1 flu emerged in Mexico, causing North America to endure the epidemic without a vaccine.
Even when an outbreak takes place in a part of the world remote to our own, poor surveillance and reporting capabilities in these areas, including Southeast Asia and Africa, can delay how quickly a pandemic is detected.
The influenza virus is currently spreading and mutating in the cells of billions of birds, pigs, bats and other animals, meaning that tracking animal populations can offer opportunities for early intervention.
But monitoring alone will not be enough to prevent against a large-scale pandemic of a deadly flu strain. Researchers are actively developing new proto, or seed vaccines, to test against newly emerging strains of the flu. From a logistics perspective, planning has to be done to ensure that treatment is available to sufferers who need it. In 2009, when the H1N1 pandemic struck Europe, even though it was a milder outbreak than in the U.S. (because of the arrival of a vaccine), many hospitals still ran out of respirators, hospital beds and nursing staff.
According to the World Health Organization (WHO) it takes four to six months to develop a vaccine against a new strain of influenza. As a result, it’s important that local government work with local healthcare providers to develop and improve clinical response capabilities, making sure that ample medication and facilities are available to treat those at risk and reduce mortality rates. Most of this responsibility lies with policymakers who work on emergency preparedness plans at a local, state and federal level.
Worst-Case Scenario
At the top of the worst-case scenario list for many experts is a pandemic of H5N1, a bird flu that has killed about six in 10 people who have contracted it and killed hundreds of millions of domestic and wild fowl. So far, this disease has only spread to humans through direct contact with infected animals and has not spread from human to human, which has kept the death toll to about 550 people since 2003. However, because the flu can mutate rapidly, it is possible for this killer virus to morph into a disease that can spread from person to person through coughing or sneezing.
To test H5N1’s pandemic capabilities, researchers at Erasmus Medical Center attempted to mutate the virus themselves to see how readily it would become airborne. While their efforts to make the virus more contagious failed, subsequent testing by their team had a chilling outcome. The team allowed the virus to mutate itself, infecting a ferret (the best animal for influenza research), then infecting a second ferret with matter from the first ferret’s nose, and so on. After repeating this cycle 10 times, the virus itself had mutated to become as easily transmittable as the seasonal flu.
While H5N1 gets a lot of attention from the scientific community and the media, scientists are also watching out for other emerging viruses. Presently, there are 16 known forms of influenza hemagglutinin (the H strain) and nine known varieties of neuraminidase enzyme (the N in the strain name), as well as different subtypes within each type. There is the potential for new enzymatic combinations and recombinations, with potentially deadly outcomes.
While the exact likelihood of an H5N1 pandemic spreading among the human populations is still unknown, it is expected to be a low probability event. But its potential impact warrants preparation, much in the same way that we prepare for terrorist events.