Yes, some people appear to have a natural resistance or innate immunity to SARS-CoV-2, often called "super avoiders," who are repeatedly exposed but never get infected, potentially due to genetic factors or a very effective early innate immune response that stops the virus before it takes hold, a key area of ongoing research.
These include their overall health, how much of the virus was shed by COVID-stricken people around them, and the strength of their immune systems. Even if genes do contribute to immunity, the protection might depend on a fortuitous combination of factors, including variations in other genes as well.
Blood group O was associated with a lower risk of COVID-19 than blood groups A, B, and AB. High titers of preexisting natural anti-A antibodies, found in people with type O and type B blood, and anti-B antibodies, found in people with type O and type A blood, also were associated with a lower risk of COVID-19.
For example, a study discovered that some individuals have a variation in genes coding for HLA (human leukocyte antigens), and they are therefore less likely to develop symptoms after an infection.
The secret lies with the human leukocyte antigen (HLA), or protein markers that signal the immune system. A mutation in one of the genes coding for HLA appears to help virus-killing T cells identify SARS-CoV-2 and launch a lightning attack.
Like adults, children and teens with obesity, diabetes, asthma or chronic lung disease, sickle cell disease, or who are immunocompromised can also be at increased risk for getting very sick from COVID-19. Check out Stay Up to Date on COVID-19 Vaccines for more information on vaccinating your child.
Total cumulative data show that Black, Hispanic, AIAN, and NHOPI people have experienced higher rates of COVID-19 cases and deaths than White people when data are adjusted to account for differences in age by race and ethnicity.
Symptoms
However, about 6% of people who get COVID never fully recover. They may have symptoms for three months or several years after getting the virus. This is called long COVID.
“Some of us inherit a set of immune system genes that are particularly good at dealing with one particular virus,” explains Daniel Davis, professor of immunology at the University of Manchester and author of The Compatibility Gene, which explores how immune system genes shape our biology.
While Shimizu and Colleagues10 found that blood type B was associated with longevity, Mengoli and Colleagues6 and Brecher and Hay12 concluded that group B was inversely correlated with age. In addition, there are isolated reports of group A7 and group O9 being associated with longevity.
Rh-negative blood is rare because it's a recessive genetic trait, meaning you need two copies of the non-functional gene (one from each parent) to be Rh-negative, while Rh-positive (having the D antigen) is dominant. This recessive nature means it's less common overall, appearing most frequently in specific populations like Western Europeans, possibly due to historical genetic bottlenecks or selective pressures, though the exact evolutionary reasons are still debated.
If you're O+, it turns out your immune system may be naturally stronger. Studies suggest that people with this blood type have a more robust immune response, which means they can fight off infections with greater ease.
What are the signs of a strong immune system?
7 Steps to Take After a Virus Has Hit Your Home
While anyone who gets COVID-19 can develop Long COVID, studies have shown that some groups of people are more likely to develop Long COVID than others, including (not a comprehensive list): Women. Hispanic and Latino people.
Researchers in Japan have pinpointed a biological cause of Long COVID brain fog using advanced PET brain imaging. They discovered widespread increases in AMPA receptor density linked to cognitive impairment and inflammation.
New information shows that getting COVID more than once could affect your long-term health. By now, most people have had COVID at least once. Those with compromised immunity, a lack of immunization, or who have not used precautionary measures, may have even had multiple bouts of the infectious disease.
Since August 24, 2025, a total of 33,059 COVID-19 detections have been reported (from 434,597 tests). A total of 25,497 laboratory-confirmed COVID-19 detections with age information have been reported. Individulas aged 65+ years reported the highest proportion of all detections (59%) (Figure 5).
The immune system plays a crucial role in the susceptibility, persistence, and clearance of these infections. With 70–80% of immune cells being present in the gut, there is an intricate interplay between the intestinal microbiota, the intestinal epithelial layer, and the local mucosal immune system.
An immunoglobulins blood test can help your health care provider diagnose different types of health conditions that may affect your immune system. A variety of conditions can cause abnormal levels of IgM, IgG, and/or IgA, such as: Autoimmune disorders.
The "worst" autoimmune diseases are subjective but often ranked by severity, impact on life expectancy, and organ damage, with top contenders including Giant Cell Myocarditis (deadly heart inflammation), Vasculitis (blood vessel inflammation like GPA), Systemic Lupus Erythematosus (multi-organ attacks), Multiple Sclerosis (nervous system damage), and Type 1 Diabetes (pancreas destruction). These conditions can severely affect quality of life, cause permanent disability, and reduce lifespan if not managed effectively, though rare ones like Giant Cell Myocarditis are acutely fatal.
High levels of a key gene in volunteers who managed to fight off infection quickly suggests it has a protective effect against SARS-CoV-2, according to a new study from researchers at UCL, the Wellcome Sanger Institute and Imperial College London.
Deaths by Demographics
In 2023, not-Hispanic or Latino experienced 66% of all preventable deaths, down from 67% in 2022. The next largest proportion of deaths occurred to Black not-Hispanics who experienced 16% of deaths, up from 15% in 2022. Hispanic or Latino continued to experience 13% of the deaths in 2023.
Age is the strongest risk factor for severe COVID-19 outcomes. Patients with one or multiple certain underlying medical conditions are also at higher risk. Additionally, being unvaccinated or not being up to date on COVID-19 vaccinations also increases the risk of severe COVID-19 outcomes.