Why it’s important to be vaccinated and boosted even though you can still get COVID-19 

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If you can still get COVID-19 after vaccination, what’s the point of getting vaccinated?  

This is a common question, and it has a simple answer. Like most preventive measures, the COVID-19 vaccines can’t provide absolute protection. However, these vaccines clearly reduce the risk of getting infected, and most importantly, they are extremely effective at reducing the risk of severe illness and death if you do get infected.  

infographic defining the terms Antibodies, Memory B-cells and T-cells.

The two mRNA COVID-19 vaccines (Pfizer and Moderna) accomplish this by introducing your immune system to the spike protein from the SARS-CoV-2 virus, allowing you to build up antibodies against it. When somebody has enough antibodies, they may be able to immediately fight off the virus and prevent infection. As immunity wanes the number of antibodies decline, and that’s when our memory B- and T-cells take action. 

Those memory B- and T-cells immediately recognize the virus and quickly build more antibodies. This process may be too slow to prevent infection. But it helps explain why people who are vaccinated against COVID-19 experience not only lower rates of infection, but significantly lower rates of hospitalization and death compared to those who aren’t vaccinated. Even as immunity wanes and new variants mutate to evade immunity (leading to more breakthrough cases), the vaccines remain impressively effective. 

“When you are vaccinated, you have a significantly lower risk of getting sick with COVID-19, and a much lower risk of severe illness and death,” said Dr. Tom Jeanne, deputy state health officer and deputy state epidemiologist.  

statistics showing a variety of CDC data about being vaccinated against COVID 19 (and boosted) and the resulting likelihood of contracting COVID-19, being hospitalized with COVID-19 and dying from COVID-19.

*Test positive and death rates 
**Hospitalization rates 

COVID-19 is a new disease, and we are still learning what the long-term consequences of infection may be. Recent large-scale studies that included millions of United States veterans indicate there may be links between COVID-19 and diabetes, cardiovascular diseases and strokes. Another study showed a link between COVID-19 and cognitive decline

Diabetes: Veterans who had COVID-19 were about 40% more likely to develop diabetes, mostly type 2, within 12 months after infection compared to people in the control group, or about 13 more people per 1,000 studied. The risk increased based on the severity of the infection, but non-hospitalized veterans with COVID-19 showed higher rates of diabetes than the control group as well.  

graphic image of a human heart surrounded by COVID-19 virus particles

Cardiovascular diseases: Veterans who had COVID-19 had increased risk of stroke and cardiovascular diseases, including heart attack, heart failure, and heart rhythm problems, between 30 days and 12 months after infection. The risks were higher for people without “any cardiovascular disease before exposure to COVID-19, providing evidence that these risks might manifest even in people at low risk of cardiovascular disease.” 

Cognitive Decline: A recent study from the United Kingdom scanned the brains of 785 participants twice.  At the time of the first scan, none of the participants had any known history of COVID-19 infection, and they were asked to perform some cognitive exercises as a baseline. In the subsequent months, 401 of the participants tested positive for COVID-19. The entire group  underwent second brain scans approximately five months after the positive diagnoses. The results showed that those who  tested positive for COVID-19 suffered a significant, harmful impact in the form of brain tissue loss and damage and other indicators of potential cognitive decline. Additionally, when the entire group repeated the cognitive exercises, the COVID-positive test subjects did not perform as well as they did initially, while the COVID-free test subjects maintained their previous performance level.  

It will be years before we know the true toll of COVID-19 and its long-term effects. How much the vaccines will prevent any long-term complications is also not yet fully understood.  

But we do know two things:  

  1. The best way to prevent COVID-19-related complications is to not be infected with COVID-19. 
  2. In addition to helping prevent infection, vaccinations greatly reduce the risk of severe COVID-19 illness, including hospitalizations, and are therefore likely to reduce the risk of long-term complications. 

“Vaccination is the single best thing you can do to reduce the risk of severe illness or long COVID,” Dr. Jeanne said.