The following factors contribute to infections among the geriatric population, according to the U.S. Department of Health and Human Services:
- Limited physiologic reserve.
- Defects in host defenses.
- Higher rates of coexistent chronic diseases (e.g., Type 2 diabetes, chronic obstructive pulmonary disease).
- Increased risk of poor nutrition.
- Loss of functionality and mobility.
- Poor responses to therapy.
- Increased frequencies of therapeutic toxicity (secondary to increased rates of liver and renal failure).
- Complications from invasive diagnostic procedures.
- Risks of infection from exposure to multidrug-resistant pathogens.
- Delays in diagnosis and therapy.
The most commonly reported healthcare-associated infections in long-term-care facilities include the following:
- Urinary tract infections. Studies suggest that the majority of UTIs in long-term care are not catheter-associated. Many older individuals develop weakened pelvic muscles, resulting in incomplete emptying of the bladder, urinary retention, and bacterial colonization of the urinary tract. Significant morbidity is associated with UTIs, and they are a leading driver of hospitalizations.
- Lower respiratory tract infections (influenza-like illness and pneumonia). Streptococcus pneumoniae (also known as pneumococcus) is the most frequently identified cause of bacterial pneumonia in people over 65. Diagnosing lower respiratory tract infections is difficult because the presentation frequently is atypical. The only evidence of infection might be general malaise, anorexia, nonspecific weakness, behavioral changes or weight loss. Altered mental status has been found to be the most common presenting symptom in 40 percent of elderly adults with bacterial pneumonia. Declining oral hygiene increases the risk of aspirating bacterial agents into the lungs among individuals with difficulty swallowing or diminished cough reflex, especially in residents with underlying neurologic conditions (i.e., stroke).
- Skin and soft tissue infections. With aging, the physical barrier of the epidermis becomes thinner and protective subcutaneous fat declines, which allows for skin tears, decubitus (pressure) ulcer formation, and subsequent bacterial infection.
- Gastroenteritis (most often due to either Clostridium difficile infection or outbreaks of norovirus gastroenteritis). It is estimated that more than half of all healthcare-associated CDI cases will manifest in nursing homes.
Source: National Action Plan to Prevent Health Care-Associated Infections: Road Map to Elimination, Office of Disease Prevention and Health Promotion, Department of Health and Human Services, April 2013, https://health.gov/hcq/pdfs/hai-action-plan-ltcf.pdf