Serial surveillance for SARS-CoV-2 in hospitalized antepartum women.

Objective

During New York City’s (NYC) first wave of COVID-19 in the spring of 2020, NewYork-Presbyterian Hospital/Columbia University Irving Medical Center instituted universal SARS-CoV-2 testing for all admitted pregnant women. No visitors were permitted on the antepartum unit during the peak of the pandemic. As local infection rates decreased, 1 support person was allowed for each patient. During NYC’s second COVID-19 wave, which began in October 2020, the 1-support-person policy was maintained. Owing to concerns that hospitalized pregnant women could be within the SARS-CoV-2 14-day incubation period on admission or could become infected by asymptomatic support persons, polymerase chain reaction (PCR) testing for SARS-CoV-2 via nasopharyngeal swabs was obtained every 5 days for all women at >23 weeks’ gestation who had prolonged hospitalizations for obstetrical indications. In this letter, we report the outcomes of repeat testing.

Study Design

From November 23, 2020, to March 3, 2021, results of all SARS-CoV-2 PCR swabs sent from the antepartum unit were collected. Serial testing was only performed for patients whose admission test was negative and who could require urgent delivery, because an unrecognized SARS-CoV-2 infection could have considerable anesthetic and neonatal implications. Results were evaluated in the context of the local 7-day positivity rate for our hospital’s ZIP code (10032). Our visitor policy is presented in the Table .

Table

Visitation guidelines for obstetrical units at NewYork-Presbyterian Hospital/Columbia University Irving Medical Center

- Support persons must be 18 y or older.

- One designated support person is selected by patient and, when possible, remains the same person throughout the admission.

- Upon arrival, support persons undergo temperature and symptom screening, screening for COVID-19 illness within the past 10 d, COVID-19 exposure within the past 14 d, and relevant travel history as per New York State Department of Health restrictions.

- Sick visitors are not permitted to enter the hospital.

- Upon arrival, support persons perform hand hygiene and must wear a surgical mask throughout their visit. If cloth masks are used, they must be worn over a surgical mask.

- Support persons must remain at the patient’s bedside throughout their visit.

- Visitation h for obstetrical patients are 24 h a day.

Zork. Serial surveillance for SARS-CoV-2 in hospitalized antepartum women. Am J Obstet Gynecol 2021.

Results

A total of 169 swabs were performed on 72 patients. None of these patients became SARS-CoV-2 positive during their hospitalization. Patients were retested an average of 2.34 times (range, 1–13). The 7-day positivity rate for our hospital’s zip code was 5.3% on November 28, 2020 and peaked at 10.2% on January 8, 2020. These rates were higher than the overall positivity rate for Manhattan and all of NYC during the same time.

Conclusion

Despite allowing visitors to the antepartum unit during a time of high local positivity rate for SARS-CoV-2, hospitalized pregnant women did not become infected. This may reflect the effectiveness of visitor screening for COVID-19 symptoms upon presenting to the hospital, the self-monitoring of symptoms by our patients’ family members, the enforcement of universal masking of patients and visitors, social distancing, and hand hygiene. This testing practice, intended to promote safety, proved to be costly in terms of testing resources and staff workload without adding clear benefit. In addition, several women refused repeat testing owing to discomfort. Similar findings were noted in a larger nonobstetrical patient population. Serial SARS-CoV-2 testing was performed every 5 days in 4580 hospitalized patients in a large tertiary care center, and 96.9% had negative results. Only 1% converted from a negative to a positive test during admission. We plan to continue to test all admitted pregnant women for SARS-CoV-2 and to perform a second test on hospital day 5, in case a patient is admitted during the incubation period for SARS-CoV-2. Subsequent testing for SARS-CoV-2 will be performed for patients with signs, symptoms, or exposure or in anticipation of delivery. We hope our experience will be useful to other institutions faced with similar challenges.