Comparing C. Diff Infection Rates Before and During COVID-19 Pandemic

Clostridioides difficile (C. diff) infection decreased in both proportion and number among hospital inpatients during the novel coronavirus disease 2019 (COVID-19) pandemic peak months compared to the pre-COVID era, while C. diff infection among outpatient visits remained stable, according to a poster presented at the American College of Gastroenterology (ACG) 2020 conference.

Investigators from the University of Virginia Health System wrote that C. diff infections are common, although from 2011 to 2017 there was a noted decline in the spread of the disease. However, many health care systems have noted a dramatic shift in C. diff infections and infection control throughout the COVID-19 pandemic.

Because of this shift, the investigators conducted a retrospective study at a single center to determine if the changes in the hospital census and infection control during the pandemic affected rates of C. diff infection. They also surveyed 13 primary care providers regarding empiric C. diff infection prescribing habits, in an effort to determine if empiric treatment was offered in lieu of testing during COVID-19.

The study authors collected inpatient admissions and outpatient visits between November 2019 and May 2020 and included all patients who had a PCR test for C. diff infection. They also noted the PCR result and the setting from which it was taken. Then, they compared C. diff infection rates pre-COVID-19 (November-February 2020) and during COVID (March-May).

There was a decrease in the number of inpatient admissions in the post-COVID-19 period compared to the pre-COVID period, according to the investigators.

In November, December, January, and February respectively, there were 2159, 2233, 2314, and 2088 inpatient admissions compared to 1786, 1421, and 1876, respectively, in March, April, and May.

From this group of inpatient admissions, the number of positive C. diff infection tests decreased in the post-COVID-19 period (when the mean was 10) compared to the pre-COVID-19 period (when the mean was 19). Additionally, the proportion of positive C. diff infection tests over monthly admissions decreased in the post-COVID-19 period compared to the previous period, the study authors said. When they controlled their analysis for age and gender, the study authors determined that the odds of testing positive for C. diff infection decreased post-COVID-19.

Among the outpatient visits, the number of positive C. diff infection tests per month was unchanged pre-COVID-19 compared to post-COVID-19. The mean remained at about 8 during that time. The numbers of positive C. diff infection tests and negative C. diff infection tests remained relatively similar throughout the pre- and post-COVID-19 months.

As for the primary care physicians, only 1 of the 13 respondents empirically prescribed antibiotics for C. diff infection during COVID-19, the study authors discovered.

“Reasons for inpatient C. diff infection downtrend may include decrease in elective procedures/ admissions that pose risk for C. diff infection or heightened awareness of infection control best-practices due to COVID-19,” the study authors wrote. “Further research is necessary to evaluate C. diff infection trends as hospital census fluctuates and to assess outcomes of COVID-19 infection control policy changes on C. diff infection and other healthcare infections.”