Factors Affecting the Risk of Infection

The susceptibility to infection depends on several factors.

If the integrity of the skin or mucous membranes is compromised, the chance of infection, limb amputation, and even death increases.

A reduction in the integrity or count of the white blood cells can limit the body's resistance to pathogens.

An imbalance in the pH levels of the gastrointestinal tract, genitourinary system, or skin may predispose individuals to infections.

A compromised innate or acquired immune system lowers the body's ability to fight infection. For example, alteration in the normal flora with antibiotics can cause an overgrowth of inherently pathogenic microorganisms.

An increased stress level suppresses the immune system, increasing susceptibility to illness.

Likewise, age, gender, race, and genetics affect susceptibility. For example, the elderly are less able to fight off infectious diseases.

Even fatigue, nutrition, and general health statuses affect the hosts' susceptibility. For instance, undernutrition causes immunosuppression.

Pre-existing illnesses, previous or current treatments, and certain medications influence the hosts' susceptibility.