Gender
TABLE 3 : Odds Ratios Among High-Risk and Low-Risk HCW for Gender and Comorbidities
not significantly associated with risk-group status of HCW ( Table 3 ). There were no cases of heart disease , chronic kidney disease , or chronic liver disease reported among low-risk HCW .
Odds Ratio
Male 1.82 1.09-3.04 Chronic Disease Lung 0.32 0.17-0.64 Diabetes 0.55 0.21-1.41 Hypertension 0.63 0.38-1.06 Other Immunosuppression 0.99 0.34-2.93 Exposed to Person with COVID-19 7.30 3.84-13.88
TABLE 4 : SARS-CoV-2 IgG Overall Positivity with Breakdown by Hospital and Exposure Level
SARS-CoV-2 IgG was positive in nine of 1,042 ( 0.86 %) HCW ( Table 4 ). The rate was similar across all four institutions ( Table 4 ). SARS-CoV-2 IgG was positive in five of 835 ( 0.60 %) HCW in the high-risk group and four of 176 ( 2.27 %) HCW in the lowrisk group . Lower seroprevalence in the high-risk versus low-risk group was not statistically significant ( p = 0.054 ). None of the 31 EVS workers who participated tested positive . Environmental service workers were excluded from seroprevalence analysis due to absence of risk stratification ( Table 4 ). Of nine HCW who tested positive , two had previously tested positive by SARS-CoV-2 PCR .
DISCUSSION
95 % Confidence Interval
SARS-CoV-2 IgG Test Positive Negative Total J . W . Ruby Memorial Hospital 2 ( 0.40 %) 497 ( 99.60 %) 499 United Hospital Center 2 ( 0.89 %) 222 ( 99.11 %) 224 Berkeley Medical Center 5 ( 2.59 %) 188 ( 97.41 %) 193 Camden Clark Medical Center 0 ( 0.00 %) 126 ( 100.00 %) 126 All Hospitals 9 ( 0.86 %) 1033 ( 99.14 %) 1042 High Risk Exposure 5 ( 0.60 %) 830 ( 99.40 %) 835 Low Risk Exposure 4 ( 2.27 %) 172 ( 97.73 %) 176 EVS Workers 0 ( 0.00 %) 31 ( 100.00 %) 31 All HCW 9 ( 0.86 %) 1033 ( 99.14 %) 1042
EVS : Environmental service workers ; HCW : Healthcare workers
SARS-CoV-2 IgG antibodies typically develop one to three weeks after infection . A positive antibody test suggests a person has previously been infected with SARS- CoV-2.3 Seroprevalence has been widely studied since the inception of this pandemic . 14 – 16 Seropositivity appears to induce some future immunity , though characterizing this immunity is still ongoing . Immunity due to previous infection does appear to vary based on age and pre-existing conditions as well as time since previous infection . 17 To our knowledge , this is the largest study of seroprevalence in Appalachia given its multi-center design , and the first of its kind in WV .
The COVID-19 vaccination was first introduced to high-risk populations , including HCW , in December 2020 . 11 Since its introduction , there have been public health challenges in improving vaccination rates . In Eastern Kentucky and WV , surveys have shown that 52.3 % of HCW are accepting of COVID-19 vaccination . 18 This study preceded vaccination availability , but it is currently unclear if vaccination rates will improve in WV . Future work could include evaluating the seroprevalence among vaccinated HCW . This study can help build HCW confidence in the safety of their work environments and the adequacy of their PPE by showing the equivalent seroprevalence despite risk level of work . Interestingly , EVS workers had zero seroprevalence . This may be because of limited interaction with patients , but given their exposure to many regions of the hospital , PPE likely helped them prevent transmission as well .
Additionally , one important element of this study is that it was conducted with suboptimal utilization of PPE during crisis standards of care . This necessitated the reuse of CAPR shields and reprocessing of N95 masks despite their single use design . The superimposition of a supply chain crisis on the imminent need for PPE , required clinically guided interventions for different levels of exposure that maximized the available PPE supply and its useful life . Intubation , non-invasive ventilation , nebulized therapies , and high-flow nasal cannula use on COVID-19 patients were areas of uncertain aerosol generation that required careful thought to determine whether a respirator or a simple surgical mask would be needed . This also created challenges with HCW ’ perception that PPE was being rationed , with subgroups such as medical students and residents being excluded from directly interacting with COVID-19 patients to minimize PPE utilization . Therefore , this study further highlighted that despite suboptimal supply and protracted reuse of disposable PPE , these measures still provided substantial protection against COVID-19 seroconversion . Additionally , our findings counteract the widespread ongoing doubt during the period the study was conducted regarding the effectiveness of PPE for COVID-19 transmission .
West Virginia Medical Journal • March 2024 • 17