For as long as disease has existed, there have been a select few people who have a natural resistance to certain illnesses. Whether it be a virus or genetic condition, natural resistance has long been documented and, for the most part, continues to baffle scientists. However, new research has started to give us an idea as to why some are born with such a fortunate trait.


There are some people who, despite frequent exposure to HIV, still don't contract the virus. According to The Tech, this is due to a mutation in the CCR5 gene called CCR5-delta 32.

Normally, HIV infects the body by grabbing onto the CD4 receptor and its co-receptor CCR5 and using them to enter the cell, and then reprogram it to spread throughout a body. However, in individuals with this mutation, the virus is unable to enter cells. The CCR5-delta32 mutation results in a smaller protein that isn't on the outside of the cell anymore. Most forms of HIV cannot infect cells if there is no CCR5 on the surface. People with two copies of the CCR5-delta32 gene (inherited from both parents) are virtually immune to HIV infection. This occurs in about 1 percent of Caucasian people.

The Flu

Although flu shots are readily available and highly recommended, some individuals never develop the flu even without the shot. A 2011 study investigated the science behind those who are naturally immune to the flu and found that the virus just doesn’t make them sick, even though they are still infected.

The study found significant and complex immune responses in the people who got sick and the people who didn’t, and researchers noticed changes in their blood 36 hours before some people actually felt sick, NBC Health reported. Although they understand that some people’s immune systems resist the virus, they still don’t know how or why that happens.

Genetic Disease

With genetics, parents pass down certain genes to their children, and getting two recessive copies of a gene or one dominant copy results in the trait being expressed. However, there are certain individuals, 13 to be exact, who have genetic mutations to some of the most crippling genetic diseases such as cystic fibrosis, Smith-Lemli-Opitz syndrome, and familial dysautonomia but suffer from absolutely none of the symptoms, IFL Science reported.

The reason why theses individuals are immune to certain genetic diseases is still unclear, but scientists hope that an understanding of their immunity could be used to develop treatments for those who are affected by the conditions.


During the most recent Ebola outbreak in West Africa, researchers noted that a group of women remained perfectly healthy despite many exposures to the virus. A blood analysis of one of the women showed that she had Ebola antibodies even though she had never contracted the virus, The Guardian reported. Still, the reason for this mysterious immunity is still not entirely clear.

"It may be that these people are genetically unique and have an innate response strong enough to fight Ebola before it can get a foothold,” Miles Carroll, a virologist and head of research at Public Health England’s national infection service, told The Guardian.

Read More:

HIV Immunity: Genetic Variation And Antiviral Enzymes Explain Why Some People Are Naturally Immune To HIV: Read Here

Ebola Immunity, If Verified, Could Be Used To Stop Disease Spread And Supply Transfusions: Read Here