Risk Factors For Bacterial Infections
Although every human being is exposed to innumerable bacteria, some of us are at higher risk of infection than others. Besides a weakened immune system, there are other risk factors for bacterial infection and illness.
Age. Individuals at either end of the age spectrum (neonates and the elderly) are at increased risk of bacterial infections (Chandra 1989; Chandra1992a). Neonates are most susceptible to infections by pathogens such as Escherichia coli (Chandra 2002; Chandra 2004). People older than age 60 years are susceptible to lower respiratory tract infections caused by Streptococcus pneumoniae.
Nutritional status. The human body requires a balanced diet that provides nutrients, minerals, and vitamins for a functional and effective immune response (Chandra 2004). Immune function is impacted by factors including hormonal status, age, and nutritional status (Hedlund 1995). Malnutrition results in a depressed immune system that raises the risk of infection.
Genetic predisposition. Scientists have long known that some people have a genetic predisposition to bacterial infection (Hill 2000). The Human Genome Project, which recently completed a map of the entire human genome, increased our ability to locate specific genes related to infectious disease susceptibility (Bentley 2000). Ultimately, researchers hope to use genetic testing to identify people who are at increased risk of infectious diseases, then design drug therapies that target specific genetic defects that are expressed in conjunction with diseases (Cariou 2002).