One of the first references to “getting old ain’t for sissies” was published in 1968. Fast-forward 52 years and whoever made the statement had no idea how true it would become.

In a world where we’re experiencing exponential growth in the number of people who are over 80, little is being said about the impact viruses and infections have on this aging population.

Right now, the world is abuzz with news about COVID-19, the disease caused by the novel coronavirus, with 75,000 people having contracted the disease and over 2,118 deaths as of the writing of this column.

In China, the overall fatality rate is at about 3%, but what may not be universally reported is that the number rises to almost 15% for adults in their 80s.

We often hear that those most at risk during virus outbreaks, like the seasonal flu, are the very young and the very old due to underdeveloped or weakened immune systems. But in the case of COVID-19, there are almost no fatalities for children under age 9.

This seemed odd, so I wanted to dig deeper into why older adults are so much more likely to die from this type of virus.

There are two reasons I found. The first has to do with underlying conditions. Seniors are more likely to have chronic health conditions. These are conditions that last a year or more and generally require ongoing medical attention.

Having chronic conditions like these taxes older bodies and makes it hard to fight a new virus.

The second reason the mortality rate for this disease is much higher in older adults is that immune systems change as we age. When our body is at its peak (that is, when we are younger), there is a lot of capacity to respond to stressors. This is called having a lot of “physiologic reserve.”

As we age, our body does not have as much physiologic reserve, and we become less resilient when it comes to illness.

The flu also has a significant impact in terms of its mortality on older adults. The Centers for Disease Control and Prevention estimates that between 70% and 85% of seasonal flu-related deaths occurred in people age 65 and older.

More than 12,000 people ages 65 and older died from the disease during the 2018 flu season.

The good news is that we have a vaccine for the flu and, while it is not perfect in terms of addressing all strains of the flu, it does offer much better protection than no flu vaccine at all. It also helps to protect us against sepsis.

Sepsis is also a potentially life-threatening condition. It is caused by the body’s response to an infection. The body normally releases chemicals into the bloodstream to fight an infection. Sepsis occurs when the body’s response to these chemicals is out of balance, triggering changes that can damage multiple organ systems.

While people age 65 and older make up about 12% of the American population, they make up 65% of sepsis cases in the hospitals.

One of the best ways to guard against sepsis is to vaccinate against diseases like the flu and pneumonia.

Knowledge is power. We, in the older adult population, can help ourselves by being informed and proactive in terms of getting the care we need to reduce serious illness and death.