Limited reduction in Clostridioides difficile and Methicillin-Resistant Staphylococcus aureus with the use of an aerosolized hydrogen peroxide disinfection system in tertiary health care facilities in Alberta, Canada

BACKGROUND

Nonmanual room disinfection systems may reduce the transmission of infections. A variety of systems have emerged; however, a paucity of evidence exists to make an evidence-informed decision for the implementation of a specific system. Alberta Health Services assessed one of these systems.

METHODS

A quasi-experimental prepost design assessed an aerosolized hydrogen peroxide disinfection system on 6 units at 3 acute care facilities in Alberta. To assess clinical effectiveness an interrupted time-series analysis with Poisson distribution compared changes in hospital-acquired Clostridioides difficile infection (HA-CDI) and hospital-acquired Methicillin-resistant Staphylococcus aureus (HA-MRSA) between preintervention, intervention, and postintervention periods. To assess operational feasibility cleaning turnaround time, time to operate, and utilization were considered. A participatory research framework was used to understand the benefits and challenges of operationalization.

RESULTS

Incidence rate ratio (IRR) of HA-CDI decreased by 25.7% on FMC-A and 6.9% on RAH-B. Following withdrawal, the IRR of HA-CDI continued to decrease. IRR of HA-MRSA decreased by 25.0% on RAH-B. Following withdrawal, the IRR of HA-MRSA continued to decrease. None of the results were statistically significant. The average time to operate was 3.2 hours. Utilization was between 1.7% and 25.6%. Most staff reported benefits and challenges.

DISCUSSION

None of the changes observed in HA-CDI and HA-MRSA after the introduction of the aerosolized hydrogen peroxide system were statistically significant. While most respondents reported multiple benefits and challenges in using the system, the core challenge was delays in inpatient admissions due to the time operate the system.

CONCLUSION

Successful implementation of a nonmanual room disinfection system as an addition to standard cleaning and disinfection requires significant investment and must consider a variety of factors.

Risk of transmission of respiratory viruses during aerosol-generating medical procedures (AGMPs) revisited in the COVID-19 pandemic: a systematic review

Background

In many jurisdictions healthcare workers (HCWs) are using respirators for aerosol-generating medical procedures (AGMPs) performed on adult and pediatric populations with all suspect/confirmed viral respiratory infections (VRIs). This systematic review assessed the risk of VRIs to HCWs in the presence of AGMPs, the role respirators versus medical/surgical masks have on reducing that risk, and if the risk to HCWs during AGMPs differed when caring for adult or pediatric patient populations.

Main text

We searched MEDLINE, EMBASE, Cochrane Central, Cochrane SR, CINAHL, COVID-19 specific resources, and MedRxiv for English and French articles from database inception to September 9, 2021. Independent reviewers screened abstracts using pre-defined criteria, reviewed full-text articles, selected relevant studies, abstracted data, and conducted quality assessments of all studies using the ROBINS-I risk of bias tool. Disagreements were resolved by consensus. Thirty-eight studies were included; 23 studies on COVID-19, 10 on SARS, and 5 on MERS/ influenza/other respiratory viruses. Two of the 16 studies which assessed associations found that HCWs were 1.7 to 2.5 times more likely to contract COVID-19 after exposure to AGMPs vs. not exposed to AGMPs. Eight studies reported statistically significant associations for nine specific AGMPs and transmission of SARS to HCWS. Intubation was consistently associated with an increased risk of SARS. HCWs were more likely (OR 2.05, 95% CI 1.2–3.4) to contract human coronaviruses when exposed to an AGMP in one study. There were no reported associations between AGMP exposure and transmission of influenza or in a single study on MERS. There was limited evidence supporting the use of a respirator over a medical/surgical mask during an AGMP to reduce the risk of viral transmission. One study described outcomes of HCWs exposed to a pediatric patient during intubation.

Conclusion

Exposure to an AGMP may increase the risk of transmission of COVID-19, SARS, and human coronaviruses to HCWs, however the evidence base is heterogenous and prone to confounding, particularly related to COVID-19. There continues to be a significant research gap in the epidemiology of the risk of VRIs among HCWs during AGMPs, particularly for pediatric patients. Further evidence is needed regarding what constitutes an AGMP.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13756-022-01133-8.

Surgical site infection following elective Caesarian section: a case-control study of postdischarge surveillance

OBJECTIVES

To ascertain the incidence of postoperative surgical site infection (SSI) following elective Caesarean section (CS) and to compare demographic characteristics and antibiotic administration between infected cases and noninfected control subjects.

METHODS

We conducted a retrospective case-control study of patients undergoing elective CS between 1996 and 2002 at a tertiary centre. Infection-control personnel attempted to contact by telephone all women who had had Caesarean sections, 1 month after their surgery. The women they reached were asked to complete a questionnaire based on CDC-validated criteria for infection to determine whether SSI had occurred. Control subjects without SSI were matched on the basis of having had an elective CS and by date of surgery. We then reviewed the hospital records of both groups.

RESULTS

Over the study period, 1250 elective Caesarean sections were performed and 124 infected cases were identified, giving an overall SSI incidence of 9.9%. Of the 342 women reviewed (124 cases, 218 control subjects), 23% received prophylactic intraoperative antibiotics. Cases and control subjects differed significantly in terms of estimated blood loss, with fewer control subjects having excessive blood loss (P = 0.04). Among those women receiving postoperative antibiotics, case subjects received a significantly higher number of doses than did control subjects (P = 0.003). The groups did not differ significantly in terms of overall antibiotic administration or other demographic variables.

CONCLUSIONS

The incidence of SSI following elective CS according to postdischarge surveillance was 9.9%, which is higher than expected for a low-risk procedure. Because follow-up was not possible for all cases, this incidence may be an underestimate. Underuse of antimicrobial prophylaxis may also be a contributing factor, because prophylactic antibiotics were administered in less than 25% of cases.