For example, a new statistical study has found that major pandemics are much more common than you might think. In fact, the team found that a pandemic with a level of impact similar to COVID-19 has an approximately 2% chance of occurring each year.
When you add that up over a lifetime, that means we each have a 38% chance of experiencing a big one at least once, and the odds seem to get worse over time.
“The most important thing to remember is that major pandemics like COVID-19 and the Spanish flu are relatively likely,” said William Pan, a global environmental health researcher at Duke University.
The team looked at the historical record of epidemics from the year 1600 until now. They found 476 documented epidemics, about half of which had a known number of fatalities. About 145 caused less than 10,000 deaths, while 114 more that we know of existed, but not the number of deaths.
It is important to note that currently active infectious diseases were excluded from the analysis, which means there is no COVID-19, HIV or malaria.
The team used detailed modeling with a generalized Pareto distribution to analyze the data, finding that the annual number of outbreaks is extremely variable, and that an extreme outbreak like the Spanish flu of 1918-1920 had a likelihood of occurring. produce somewhere between 0.3 and 1.9% each. year over the past 400 years.
“The slow decrease in probability with epidemic intensity implies that extreme epidemics are relatively likely, a property previously undetected due to short observational records and stationary analysis methods,” the team writes in the paper. .
But neither is it a constant probability – it is increasing.
Over the past 50 years, we have seen increasing levels of new pathogens spread through humans. SARS-CoV-2 is the most obvious example, but even in the last few decades we have had swine flu, bird flu, Ebola and many more.
“Together with recent estimates of increasing rates of disease emergence from animal reservoirs associated with environmental changes,” the team writes, “this finding suggests a high probability of observing pandemics similar to COVID-19 (likelihood of ‘experience it in his lifetime currently around 38 percent), which could double in the coming decades. “
So even as we recover from a current outbreak, it’s important that we don’t assume that we won’t see another life-changing pandemic soon enough.
In fact, if we play our cards right, our response and resources for COVID-19 can prepare us for the next pandemic.
“This underscores the importance of an early response to epidemics and building capacity for pandemic surveillance at local and global scales, as well as establishing a research agenda to understand why large epidemics are becoming more common,” said Pan. .
If the statistics have anything to do with it, the next pandemic is coming – just let’s hope we don’t forget the past.
The research was published in PNAS.