A risk factor is something that raises a person's chances of getting a disease or health problem. A person can get a cold or flu virus with or without the risks below. The more risks a person has, the greater the chances are.
Viral upper respiratory infections are very common. Most adults in the US get several per year. Children get even more.
Things that raise the risk of getting a cold or the flu are:
Smoking
Adults who smoke have more colds. Smokers also have a higher risk for complications from colds and the flu.
Not Washing Hands Enough
Colds and influenza are passed through person-to-person contact. People who do not wash their hands have a higher risk of getting and spreading colds or flu. They can get cold or flu viruses on their hands and then touch their nose, mouth, or eyes.
Crowded Areas
People in crowded living conditions have a higher risk, as well.
Health Conditions
People who have certain health conditions have a higher risk for problems from colds or the flu. Examples include people who:
Age
Children and older people have a higher risk for more problems.
Disability
People with disabilities may have trouble protecting themselves from illness. They may not be able to tell anyone about their symptoms. These issues raise their risk for getting sick and having more problems.
Stress and Other Mental Health Concerns
Lots of stress, anxiety or depression can raise the risk of getting colds and flus.
References
Common cold. Merck Manual Professional Version website. Available at: http://www.merckmanuals.com/professional/infectious-diseases/respiratory-viruses/common-cold. Accessed March 10, 2022.
Influenza in adults. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/influenza-in-adults. Updated September 27, 2016. Accessed March 10, 2022.
Influenza. Merck Manual Professional Version website. Available at: http://www.merckmanuals.com/professional/infectious-diseases/respiratory-viruses/influenza. Accessed March 10, 2022.
Upper respiratory infection (URI) in adults and adolescents. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/upper-respiratory-infection-uri-in-adults-and-adolescents-18. Accessed March 10, 2022.