Increased prescribing of antibiotics commonly used for respiratory infections, including azithromycin, ceftriaxone, and doxycycline was observed in nursing homes (NH) during the COVID-19 pandemic however antibiotic prescribing was not linked to resident diagnosis. Therefore, our objective was to characterize antibiotic prescribing in residents with SARS-CoV-2 infection in a large cohort of US NHs.We conducted a retrospective cohort study using PointClickCare (PCC) data containing longitudinal NH electronic health records. We included 4,891 NHs that reported ≥1 medication order/month from April 2020-November 2021. We identified the first onset of SARS-CoV-2 infection using ICD-10-CM diagnosis code U07.1. To validate the number of SARS-CoV-2 infections per facility captured in PCC, we compared the total number of SARS-CoV-2 infections documented in PCC to those reported to the National Healthcare Safety Network (NHSN). Antibiotic orders were determined to be associated with a SARS-CoV-2 infection if 3 days before or ≤7 days after diagnosis. We characterized the proportion of residents with a SARS-CoV-2 infection with an associated antibiotic by month.We included 2,086 (43%) NHs that had ≤20% difference in total number of SARS-CoV-2 infections documented in PCC and reported to NHSN. From April 2020-November 2021, a total of 118,180 residents with a SARS-CoV-2 infection were identified and 24% had an associated antibiotic prescription (N=27,972). The highest prescription rate (30%, 95% Confidence Interval [29%-31%]) was observed in April 2020 and varied by less than 8% from May 2020-November 2021 (Fig.1). The most commonly prescribed antibiotics were azithromycin (53%), doxycycline (13%) and ceftriaxone (10%). An antibiotic prescription was linked to up to a quarter of NH residents with SARS-CoV-2 infection, highlighting potential opportunities for avoiding unnecessary antibiotic prescribing for viral infections in NHs. Appropriate antibiotic prescribing in NH populations is important to reduce potential harm when antibiotics offer no treatment benefit to the resident. Identifying facility-level characteristics that lead to variability in antibiotic prescribing is a next step to inform antibiotic stewardship interventions.All Authors: No reported disclosures.

Zika virus is a cause of microcephaly and brain abnormalities (1), and it is the first known mosquito-borne infection to cause congenital anomalies in humans. The establishment of a comprehensive surveillance system to monitor pregnant women with Zika virus infection will provide data to further elucidate the full range of potential outcomes for fetuses and infants of mothers with asymptomatic and symptomatic Zika virus infection during pregnancy. In February 2016, Zika virus disease and congenital Zika virus infections became nationally notifiable conditions in the United States (2). Cases in pregnant women with laboratory evidence of Zika virus infection who have either 1) symptomatic infection or 2) asymptomatic infection with diagnosed complications of pregnancy can be reported as cases of Zika virus disease to ArboNET* (2), CDC's national arboviral diseases surveillance system. Under existing interim guidelines from the Council for State and Territorial Epidemiologists (CSTE), asymptomatic Zika virus infections in pregnant women who do not have known pregnancy complications are not reportable. ArboNET does not currently include pregnancy surveillance information (e.g., gestational age or pregnancy exposures) or pregnancy outcomes. To understand the full impact of infection on the fetus and neonate, other systems are needed for reporting and active monitoring of pregnant women with laboratory evidence of possible Zika virus infection during pregnancy. Thus, in collaboration with state, local, tribal, and territorial health departments, CDC established two surveillance systems to monitor pregnancies and congenital outcomes among women with laboratory evidence of Zika virus infection(dagger) in the United States and territories: 1) the U.S. Zika Pregnancy Registry (USZPR),( section sign) which monitors pregnant women residing in U.S. states and all U.S. territories except Puerto Rico, and 2) the Zika Active Pregnancy Surveillance System (ZAPSS), which monitors pregnant women residing in Puerto Rico. As of May 12, 2016, the surveillance systems were monitoring 157 and 122 pregnant women with laboratory evidence of possible Zika virus infection from participating U.S. states and territories, respectively. Tracking and monitoring clinical presentation of Zika virus infection, all prenatal testing, and adverse consequences of Zika virus infection during pregnancy are critical to better characterize the risk for congenital infection, the performance of prenatal diagnostic testing, and the spectrum of adverse congenital outcomes. These data will improve clinical guidance, inform counseling messages for pregnant women, and facilitate planning for clinical and public health services for affected families.