SARS-CoV2 positive RT-PCR incidence in symptomatic healthcare workers, clinical evolution, outcome and household transmission, experience from a French hospital

Abstract

Although healthcare workers (HCW) have been particularly affected with the SARS-CoV2 all around the world, detailed data is still rare. Here, we explored rates of infection, clinical characteristics, occupational exposure and household transmission among all symptomatic HCW screened with PCR SARS-CoV2 between March 17th (the beginning French lockdown) and April 20th. This period coincides with the French highest epidemic period. SARS-CoV2 detection by nasopharyngeal swab using RT-PCR assay was proposed to symptomatic (new cough or dyspnea) HCW. Constants were gathered by a trained nurse. The survey together with clinical exam was performed by a physician. All patients with positive PCR were followed by phone call at D5, D7, D10, and D14 after illness onset. Data on occupational profile, living situation, household together with self-isolation and mask use at home were gathered as well as cases in the household. The epidemic curve was compared with the curve in general population during the same period. Factors associated with a positive PCR were explored by univariate and multivariate analyses. The incidence rate of symptomatic SARS-CoV2 was estimated of 5.5% (110/2000). A total of 110 (35%) symptomatic HCW of the 314 were tested positive, of them 9 (8%) were hospitalized. The local epidemic curve was similar with the one in general population with a peak around March 31st. ROC curve AUC was 0.65 for the presence of anosmia at screening, and 70% of positive HCW declared anosmia 7 days after onset versus 45% of HCW positive at screening ( P < 0.001). Factors independently associated in multivariate analysis with a positive PCR were occupational profile with direct patient facing (OR: 3.1 [1.1–8.8], P < 0.03), and presence of anosmia (OR: 5.7 [IC 3.1–10.6], P < 0.0001). Being a current smoker was associated with a negative PCR (0.3 [0.1–0.7], P = 0.005). Transmission from HCW to household members was reported in 9 (14%) cases, and 2 deaths occurred. Overall, self-isolation (a separate room) was possible in 52% of positive HCW and only 31% had the possibility to wear a mask. This is the first French study to report rates of infection in HCW during the peak of the SARS-CoV2 epidemic in France and the lockdown period underlying the risk related to occupational profile. Furthermore, this highlights the risk for HCW to household transmission and the lack of protection in the households during the peak of the epidemic.