Whether it’s viral or bacterial, you hope to bounce back quickly and return to your usual routine when you get an infection. In most cases, that’s what happens. That’s because the organized team of players called your immune system defeats the foreign invader, declares victory, and you recover. But do all infectious viruses disappear without a trace after keeping you under the weather for a few days? Surprisingly, some viruses can strangle your immune system and make it weak, vulnerable, and less capable of protecting you against future infections. Here, Kevin Dalby, Austin professor of chemical biology and medicinal chemistry, explains how our immune system works and why some viruses weaken the immune system for years.

One example of a viral infection that destabilizes the immune system and suppresses its function is the measles virus. Measles isn’t a viral infection you see as much as in the past, thanks to the measles vaccine, but it’s making a resurgence because of an increase in the number of kids not being vaccinated. An outbreak of measles occurred at Disneyland several years ago, which sickened over 100 people.

Post-Viral Immune Suppression

Scientists have long known that when children develop a measles infection, they’re more prone to other diseases for a few months afterward. Still, more recent research shows that the “immune amnesia,” as it’s called, can last for years after a bout with the measles virus.

How does immune suppression or “amnesia” occur? In response to the measles virus, immune cells called B-cells and T-cells launch a coordinated attack to fight the virus. But, in some cases, the virus can unexpectedly overwhelm the immune cells. Rather than the B and T-cells killing the virus, the virus attaches to the immune cells, disrupts their function, and destroys them, leaving fewer infection-fighting T-cells and B-cells capable of destroying the next virus that poses a threat. This is what happens in the case of an infection by the measles virus.

The measles virus may wipe out even the B and T memory cells produced in response to vaccines, leaving kids and adults vulnerable and at risk for infection. After a measles infection, memory B and T cells have to rebuild and retrain to respond to the measles virus, a process that can take years. Until immune re-education occurs, a measles sufferer is at higher risk of falling ill and even dying from other viral infections.

The Impact of Other Viruses

Could other viruses pose a similar risk of immune suppression? Interestingly, research shows that viruses such as HIV, hepatitis C virus (HCV), hepatitis B virus (HBV), and some herpesviruses, can cause substantial tissue damage and transient suppression of immune function. When a virus or bacteria gains enough of a foothold to cause illness, it can inflict bodily stress on several tissues, organs, and systems, including the immune system. Complete recovery and return to balance and normalcy take time.

The Bottom Line

Viruses can damage the immune system short-term and reduce its ability to fight off infection in the long-term. The research shows the importance of supporting your immune system to protect you against viral and bacterial infections. You can do that by managing stress, wearing a mask in public places, getting at least 7 hours of sleep per night, eating a nutrient-dense diet, and avoiding unhealthy habits like smoking and consuming too much alcohol. Make supporting your immune system a priority, so it can keep you protected.

About Kevin Dalby

Dr. Kevin Dalby is a chemical biology and medicinal chemistry professor currently working on cancer drug discovery. At the College of Pharmacy at The University of Texas, he examines the mechanisms of nature and cancer to develop new treatments and teach and motivate students to conduct research. Dalby is optimistic about the future of cancer treatments.