TABLE 13-2.
Host Factors That Influence Exposure, Infection, and Disease
| Factors That Influence Exposure |
| Animal exposure, including pets |
| Behavioral factors related to age, drug use, alcohol consumption |
| Blood or blood product receipt |
| Child daycare attendance |
| Closed living quarters: military barracks, dormitories, homeless shelters, facilities for the elderly and mentally handicapped, prisons |
| Food and water consumption |
| Familial exposure |
| Gender |
| Hospitalization or outpatient medical care |
| Hygienic practices, including toilet training and hand washing |
| Occupation |
| Recreational activities, including sports |
| Recreational injection drug use |
| Sexual activity: heterosexual and homosexual, type and number of partners |
| School attendance |
| Socioeconomic status |
| Travel, especially to developing countries |
| Vector exposure |
| Factors That Influence Infection and the Occurrence and Severity of Disease |
| Age at the time of infection |
| Alcoholism |
| Anatomic defect |
| Antibiotic resistance (agent) |
| Antibiotic use (host) |
| Coexisting noninfectious diseases, especially chronic |
| Coexisting infections |
| Dosage: amount and virulence of the organism to which the host is exposed |
| Duration of exposure to the organism |
| Entry portal of the organism and presence of trauma at the site of implantation |
| Gender |
| Genetic makeup, especially influences on the immune response |
| Immune state at the time of infection, including immunization status |
| Immunodeficiency (specific or nonspecific): natural, drug induced, or viral (HIV) |
| Mechanism of disease production: inflammatory, immunopathologic, or toxic |
| Nutritional status |
| Receptors for organism on cells needed for attachment or entry of the organism |
HIV, human immunodeficiency virus.
Modified from Evans AS, Brachman PS. Bacterial Infections of Humans: Epidemiology and Control. 3rd ed. New York: Plenum; 1998.