Two Studies Offer Information on How COVID-19 Presents in Healthcare Workers
In a surprising finding, Chinese researchers determined that healthcare workers not on the frontlines might have been more susceptible to COVID-19 than those providing direct patient care. A Dutch study, meanwhile, reported a high rate of mild disease in hospital employees. Here is more information.
WUHAN, CHINA – Healthcare workers not on the frontlines might have been more susceptible to novel coronavirus infection than those providing direct patient care, according to the new study, something researchers say “differed from observation of previous viral disease epidemics.”
A report in JAMA Network Open discusses exposure details and clinical characteristics of health care workers with COVID-19 in Wuhan, China, which was the site of the first outbreak.
Huazhong University of Science and Technology-led researchers conducted a single-center case series including 9,684 health care workers, 110 of whom had COVID-19. The authors note “a higher rate of infection was found among those working in the low-contagion area during the early stage of the disease outbreak, especially among nurses younger than 45 years. Most health care workers with COVID-19 had non-severe disease, with an asymptomatic carrier prevalence of 0.9% and a mortality rate of 0.9%.”
The study suggests routine screening could be helpful in identifying asymptomatic carriers.
A structured questionnaire was used to collect epidemiological, and demographic information from Jan. 1, 2020 to Feb. 9, 2020. Clinical, laboratory, and radiologic information was collected from electronic medical records, and 335 medical staff were randomly sampled to estimate the prevalence of subclinical infection among a high-risk, asymptomatic population. Samples from surfaces in health care settings were also collected.
Researchers determined that healthcare workers at Tongji Hospital had an infection rate of 1.1%. Of them, 70 (71.8%) were women, and they had a median (interquartile range) age of 36.5 (30.0-47.0) years.
“Seventeen (15.5%) worked in fever clinics or wards, indicating an infection rate of 0.5% (17 of 3110) among first-line HCWs,” the authors write. “A total of 93 of 6574 non–first-line HCWs (1.4%) were infected. Non–first-line nurses younger than 45 years were more likely to be infected compared with first-line physicians aged 45 years or older (incident rate ratio, 16.1; 95% CI, 7.1-36.3; P < .001).”
The study points out that the prevalence of subclinical infection was 0.74% (1 of 135) among asymptomatic first-line HCWs and 1.0% (2 of 200) among non–first-line HCWs. The authors also emphasize that no environmental surfaces tested positive.
Most, 84.5%, of HCW with COVID-19 had non-severe disease, while 1 (0.9%) died. The five most common symptoms were fever (67 [60.9%]), myalgia or fatigue (66 [60.0%]), cough (62 [56.4%]), sore throat (55 [50.0%]), and muscle ache (50 [45.5%]). The main routes of exposure for HCWs were determined to be contact with indexed patients (65 [59.1%]) and colleagues with infection (12 [10.9%]) as well as community-acquired infection (14 [12.7%].
“In this case series, most infections among HCWs occurred during the early stage of disease outbreak,” researchers conclude. “That non–first-line HCWs had a higher infection rate than first-line HCWs differed from observation of previous viral disease epidemics. Rapid identification of staff with potential infection and routine screening among asymptomatic staff could help protect HCWs.”
Tongji Hospital is a large comprehensive tertiary hospital in Wuhan with more than 7,000 beds and 9,648 staff members. It was designated for the treatment of patients with COVID-19 during the epidemic outbreak.
“Frontline HCWs could be at high risk of infection because of close contact with these patients,” researchers suggest. “Moreover, HCWs with infection could cause secondary transmission among patients, family members, and the community. Therefore, it is important to investigate the infection risk of HCWs and the clinical characteristics of affected cases.”
A Dutch study, meanwhile, looked at the prevalence and clinical presentation of coronavirus disease 2019 among health care workers with self-reported fever or respiratory symptoms in two Dutch hospitals within two weeks after the first patient with coronavirus disease 2019 was detected in the Netherlands. The cross-sectional study, also published by JAMA Network Open, included 1353 health care workers with self-reported fever or respiratory symptom; 6% were determined to be infected with SARS-COV2. Most healthcare workers with coronavirus disease 2019 experienced mild disease, and only 53% reported fever, according to the authors.
“The high prevalence of mild clinical presentations, frequently not including fever, suggests that the currently recommended case definition for suspected coronavirus disease 2019 should be used less stringently,” the study concludes.