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COVID-19 transmissibility during labor and vaginal delivery

Published:October 11, 2022DOI:https://doi.org/10.1016/j.ajogmf.2022.100770

      OBJECTIVE

      The COVID-19 pandemic raised uncertainty about the appropriate personal protective equipment (PPE) required for healthcare personnel (HCP) in the labor and delivery unit (L&D).

      Centers for Disease Control and Prevention. Infection control guidance for healthcare professionals about coronavirus (COVID-19). 2019. Available at: https://www.cdc.gov/coronavirus/2019-nCoV/infection-control.html. Accessed December 10, 2021.

      ,

      World Health Organization. Infection prevention and control during health care when novel coronavirus (nCoV) infection is suspected. 2020. Available at: https://www.who.int/publications/i/item/infection-prevention-and-control-during-health-care-when-novel-coronavirus-(ncov)-infection-is-suspected-20200125. Accessed December 10, 2021.

      Given the mechanism of SARS-CoV-2 transmission, providers involved in procedures that produce respiratory aerosols (eg, intubations) are instructed to wear N95 respirators.
      • Klompas M
      • Baker MA
      • Rhee C.
      Airborne transmission of SARS-CoV-2: theoretical considerations and available evidence.
      ,
      • Klompas M
      • Baker M
      • Rhee C.
      What is an aerosol-generating procedure?.
      The Centers for Disease Control and Prevention and the American College for Obstetricians and Gynecologists speculate that labor and vaginal delivery, which often involve heavy breathing and expulsive effort, may produce aerosols, however, limited data are available to inform PPE recommendations.
      • Mok T
      • Harris E
      • Vargas A
      • et al.
      Evaluation of respiratory emissions during labor and delivery: Potential Implications for Transmission of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2).
      This study aimed to assess the prevalence of SARS-CoV-2 RNA in L&D during routine obstetrical care to better characterize the exposure risk.

      STUDY DESIGN

      We performed a cross-sectional examination of SARS-CoV-2 RNA presence during routine care of SARS-CoV-2 positive patients in L&D. All admitted patients were screened for COVID-19 per hospital protocol; positive patients admitted for labor met the inclusion criteria. We collected the following samples during both the first and second stage of labor: (1) near air sample <6 feet from patient's face, (2) far air sample >6 feet from patient's face, and (3) PPE surface swab from the outermost facemask or face shield of the primary nurse. Two specimens were collected during the second stage only, namely (4) provider air sample from the delivering provider's lapel and (5) agar plate placed on the delivery table. The presence of SARS-CoV-2 RNA was determined using reverse transcriptase–polymerase chain reactions. The presence or absence of a face mask on the patient was recorded.

      RESULTS

      Samples from the air, PPE, and agar plates were collected during 5 vaginal deliveries of COVID-19 positive patients (Table). Throughout collection, 1 patient wore a face mask continuously, 3 wore their face masks inconsistently, and 1 did not wear a face mask. Each patient had a missing specimen owing to logistical or clinical limitations. One specimen tested positive for SARS-CoV-2 RNA, which was the agar plate from the vaginal delivery of the patient not wearing a face mask. All other samples yielded negative tests.
      Table 1Presence of SARS-CoV-2 RNA in specimens collected from COVID-19 positive patients in the labor and delivery unit
      Mahn Hawks. SARS-CoV-2 exposure during labor and delivery. Am J Obstet Gynecol MFM 2022.
      Patient mask statusNear
      Near air sample <6 ft from patient face
      Far
      Far air sample >6 ft for patient face
      PPE
      PPE swab of outermost face PPE (mask or shield) of primary registered nurse
      LaborDeliveryLaborDeliveryLaborDeliveryProvider
      Delivery provider air sample
      Agar plate
      Agar plate placed on delivery table at onset of second stage of labor throughout delivery.
      1Consistently presentxxxxx
      2Intermittently absentxx
      3Intermittently absentx
      4Consistently absentxx+
      5Intermittently absentxxxx
      All results were obtained using reverse transcriptase–polymerase chain reactions (RT-PCR).
      (−), negative RT-PCR result for SARS-CoV-2 RNA; (+), positive RT-PCR results for SARS-CoV-2 RNA; (X), specimen not collected.
      a Near air sample <6 ft from patient face
      b Far air sample >6 ft for patient face
      c PPE swab of outermost face PPE (mask or shield) of primary registered nurse
      d Delivery provider air sample
      e Agar plate placed on delivery table at onset of second stage of labor throughout delivery.

      CONCLUSION

      SARS-CoV-2 RNA was not detected in any air or PPE specimens collected during delivery of COVID-19 positive patients in the L&D regardless of patient masking. However, the detection of RNA on a delivery table of an unmasked patient indicates that viral spread occurs in a radius >6 ft from the patient during routine obstetrical care, which poses a risk of exposure to SARS-CoV-2 for HCP and supports the use of N95 respirators while providing patient care in the L&D. This study is limited by the small sample size and, because it was performed early in the pandemic, limited information on the positive test results such as cycle threshold or viral strain. Additional information from patients, including symptoms, presence of face mask, and viral strain data, is needed to more precisely inform PPE guidelines during the ongoing COVID-19 pandemic.

      References

      1. Centers for Disease Control and Prevention. Infection control guidance for healthcare professionals about coronavirus (COVID-19). 2019. Available at: https://www.cdc.gov/coronavirus/2019-nCoV/infection-control.html. Accessed December 10, 2021.

      2. World Health Organization. Infection prevention and control during health care when novel coronavirus (nCoV) infection is suspected. 2020. Available at: https://www.who.int/publications/i/item/infection-prevention-and-control-during-health-care-when-novel-coronavirus-(ncov)-infection-is-suspected-20200125. Accessed December 10, 2021.

        • Klompas M
        • Baker MA
        • Rhee C.
        Airborne transmission of SARS-CoV-2: theoretical considerations and available evidence.
        JAMA. 2020; ([Epub ahead of print])
        • Klompas M
        • Baker M
        • Rhee C.
        What is an aerosol-generating procedure?.
        JAMA Surg. 2021; 156: 113-114
        • Mok T
        • Harris E
        • Vargas A
        • et al.
        Evaluation of respiratory emissions during labor and delivery: Potential Implications for Transmission of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2).
        Obstet Gynecol. 2021; 138: 616-621