This article continues our focus on the leading causes of death in our area. Paying attention to these reveals much about what each of us can do to lead longer, healthier lives.
I’d like to turn your attention to the role of infectious diseases in the top ten causes of death. In 1900, the average age at death was 47 years old; today it is 78 years. The difference, largely, is due to our increased understanding of how to prevent and treat these illnesses that infect humans.
In 1900, the top three causes of death were infectious diseases—pneumonia and influenza A, tuberculosis, and gastrointestinal infections (the fourth infectious disease on the list, diphtheria, was the 10th leading cause of death). Improvements in sanitation, public health (vaccination development and delivery), and medical treatments such as antibiotics- ics, led to dramatic declines in deaths. As the impact of these diseases has been reduced or eliminated, mortality rates from other causes, especially chronic diseases like heart disease and cancer, have increased.
New mechanisms, such as noninfectious diseases, diabetes, and suicide are now among the top 10 causes of death. Today, pneumonia and influenza rank number 11th on our list for Southwest Utah and COVID-19 ranks 13th, a dramatic improvement! Today, however, influenza A still kills 20,000-80,000 people per year, often among the most vulnerable in the population.
These respiratory infections continue to be difficult to eradicate because of several factors:
- They change very rapidly. Each year the influenza virus changes enough to evade the immune system, creating the potential for disease outbreaks. Most of the time this is due to small changes that allow it to infect many people. Most
of them will get sick, with the most vulnerable possibly dying. Sometimes, there is a major shift in the virus, essentially becoming a new infection, which creates the scenario for a pandemic like we saw with H1N1 flu in 2009 and COVID-19 in Pandemics are, by definition, a widespread occurrence of disease with increased cases, complications, and deaths. - They spread very easily. Diseases that spread via droplets like influenza are easily spread from one person to another, and easily spread geographically as well. Cases of the H1N1 influenza spread around the world within weeks after
it had been discovered. - Many times, they are spread by an infected person before the person even knows that they are sick. This is the case with influen- za, COVID, RSV, measles, and many other upper respiratory infections. Many times, efforts to identify and con- trol the spread of a disease are ineffective in an environment where those primarily spreading the disease are not identifiable.
- Vaccines for these diseases are effective at decreasing the severity of the disease, but of- ten don’t prevent all cases of the disease. The one human disease that has been eradicated is smallpox, which killed 1/3 of those that got it. There hasn’t been a case since 1977, however, because we came up with a vaccine that gave permanent immunity. We have not discovered such a vaccine for influenza, although promising trials are underway.
It seems clear that we will continue to see influenza, COVID, and dozens of other respiratory illnesses as part of cold and flu season for the foreseeable future.
Those most at risk of dying from influenza include people who are either over 65 or under 2 years of age, and those with underlying chronic health conditions. The CDC lists over 21 conditions that lead to increased risk of death from influenza, including being pregnant. COVID continues to pose the most risk to the elderly and those with underlying health conditions.
Immunization against pneumonia and influenza and COVID when appropriate is the single most effective weapon we have against these leading causes of death. Because the influenza virus changes rapidly, vaccination every year is recommended, while vaccination against pneumonia requires only a one-time shot. COVID vaccination on a yearly basis is recommended for those most at risk from that disease.
We’ve recently seen a rise in cases of measles, mumps, and pertussis in our area. Outbreaks of vaccine preventable-diseases have been increasing in recent years as we see some parents who are choosing not to vaccinate their children. As the rate of vaccination declines, there are no longer enough immunized people to stop the spread of the disease in the community if outbreaks occur. There are two reasons to vaccinate: to avoid getting the illness yourself, and to avoid passing the illness on to someone else. That someone could have a limited immune system, like an infant or a person with chronic disease.
Infectious diseases are still present in our world; they still pose a very real risk to those that are infected, especially vulnerable people. The role of a health department is to identify cases of potentially dangerous diseases and try to stop from spreading. Even more important is prevention; that’s why we put out messaging about what you can do to help protect yourself. With the influenza season approaching, we’re offering vaccine “shootouts” again this fall (see inside back cover). About 35% of the population in our district gets immunized against influenza every year – I hope you will consider becoming one of them.
This article originally appeared in the Fall 2025 issue of HEALTH Magazine.