The Virtual Antimicrobial stewardship Team (VAT) study aims to evaluate, in a randomized controlled trial (RCT), the effect of a weekly virtual antimicrobial stewardship (AMS) intervention on the appropriateness of prescribing antibiotics for nursing home (NH) residents with urinary tract infections (UTI), respiratory tract infections (RTI) or skin and soft tissue infections (SSTI) compared to standard care for NH residents in Dutch NHs in the provinces of North-Holland and Flevoland. The secondary aim is to identify barriers and facilitators to implement a stewardship intervention and subsequently develop an implementation guide.

Rationale: Antimicrobial stewardship interventions have been extensively studied in hospital settings and have proven effective in reducing the number of infections with multidrug resistant micro-organisms and are also cost-effective. Therefore, AMS teams are mandatory in Dutch hospitals.

The effectiveness of an antimicrobial stewardship intervention is variable in previous studies. Also due to the perceived high workload and costs, AMS has hardly been implemented in Dutch NHs. In order to take the next step towards implementation of AMS in NHs, causality between AMS and reduction in inappropriate antibiotic prescriptions should be demonstrated. The investigators want to evaluate the process and value of the VAT approach to facilitate optimal implementation of VAT in other NHs.

Objective: To demonstrate the efficacy of weekly virtual antimicrobial stewardship team meetings in reducing inappropriate antibiotic prescriptions in Dutch NHs.

Study design: randomized, non-blinded, controlled, multicenter trial.

Study population: Clinicians working in NHs in the provinces North Holland and Flevoland.

Intervention: The VAT consists of at least a clinical microbiologist and a clinician from the NH. Ideally, a pharmacist will also attend. They conduct a weekly (digital) meeting for nine months to evaluate the antibiotic prescriptions of the clinician attending the VAT meeting, based on a standardized protocol according to the current national guidelines.

Main study parameters/endpoints: The primary outcome is the number of inappropriate antibiotic prescriptions, assessed based on an algorithm of the current clinical infection treatment guidelines, antimicrobial susceptibility test results, and clinical characteristics. Each antibiotic prescription is a record and for each record will be assessed whether the antibiotic prescription is appropriate or not. Secondary outcome measures are the incidence rate (IR) of antibiotic prescriptions and facilitators and barriers to VAT implementation.

Inclusion Criteria of clinicians:

• Working in nursing homes in the North Holland-Flevoland region and being authorized to prescribe.
• Agreeing to being randomized to intervention or control group.
• Working in a nursing home that has a medication prescription system from which prescriptions can easily be obtained for VAT meetings.
• Working in a nursing home that is connected to a microbiology lab, .that participates in this study and offers VAT meetings.
• Expected to be employed for at least four months from date of randomization.

Inclusion Criteria of antibiotic prescriptions:

• All prescriptions for antibiotics with a therapeutic indication regarding urinary tract infections, respiratory tract infections or skin and soft tissue infections for residents of nursing homes, prescribed by clinicians participating in the study, during the study period.

Exclusion Criteria of antibiotic prescriptions:

• Prescriptions for antibiotics with a prophylactic purpose.
• Prescriptions given by clinicians not participating in the study
• Prescriptions prescribed outside the study period.