Abstract

We evaluated whether hospitalized patients without diagnosed Clostridioides difficile infection (CDI) increased the risk for CDI among their family members after discharge. We used 2001–2017 US insurance claims data to compare monthly CDI incidence between persons in households with and without a family member hospitalized in the previous 60 days. CDI incidence among insurance enrollees exposed to a recently hospitalized family member was 73% greater than enrollees not exposed, and incidence increased with length of hospitalization among family members. We identified a dose-response relationship between total days of within-household hospitalization and CDI incidence rate ratio. Compared with persons whose family members were hospitalized <1 day, the incidence rate ratio increased from 1.30 (95% CI 1.19–1.41) for 1–3 days of hospitalization to 2.45 (95% CI 1.66–3.60) for >30 days of hospitalization. Asymptomatic C. difficile carriers discharged from hospitals could be a major source of community-associated CDI cases.

Clostridioides difficile infection (CDI) is one of the most commonly occurring types of healthcare-associated infection and is predominately associated with hospitals (1,2). Thus, CDI-related investigations and interventions primarily have focused on hospital settings. More recently, reports of community-associated CDI cases, in which patients without a history of recent hospitalization are infected, have become more common (3,4). Although healthcare-associated CDI remains a considerable problem, more emphasis on community-associated CDI cases also is needed.

Risk factors for community-associated CDI are similar to risk factors for hospital-associated cases. For example, antimicrobial drug and proton-pump inhibitor (PPI) use increase the risk for community-associated CDI (4,5). For some community-associated CDI cases, exposure to healthcare settings beyond hospitalization, including clinics and emergency departments (6,7), are associated with an increased risk for CDI. However, for some CDI cases, no clear exposure to healthcare facilities can be identified. To find a source of C. difficile in community settings, other potential exposures have been proposed. Food is one such potential exposure, and C. difficile has been recovered from several different edible substances, including meat and vegetables (8,9). Pets have also been implicated (10). In addition, the possibility of household transmission of CDI between family members has been proposed, and having a symptomatic family member is a risk factor for CDI (10,11).