Researchers have estimated approximately 8% of Americas have ever experienced long COVID, or lasting symptoms, following an acute COVID-19 infection. Now two recent international studies suggest that the percentage is much higher among healthcare workers and dental professionals.
40% prevalence in health workers globally
In the first study, published in BMJ Public Health, authors conducted a meta-analysis of 28 studies with a combined sample size of 6,481 healthcare workers (HCWs). Globally, HCWs have been at an increased risk for COVID-19 infections since the beginning of the pandemic in 2020, due to both exposure to the virus and work conducted in a high-stress environment that may exacerbate the risk of long-term post-viral symptoms.
The authors defined long COVID as prolonged symptoms and/or functional disability following SARS-CoV-2 infection for at least 4 weeks from onset of symptoms or from time of diagnosis, in people when SARS-CoV-2 infection was self-reported, clinically diagnosed, and/or diagnosed through a laboratory test. All studies were conducted before February 2022.
During an average follow up of 22 weeks, the pooled prevalence of long COVID among HCWs who had SARS-CoV-2 infection was 40% (95% confidence interval [CI], 29% to 51%). In three studies with follow up after 12 months, pooled prevalence dropped to 26% (95% CI, 7% to 46%).
The most common symptoms reported by HCWs were fatigue (35%), neurologic symptoms (25%), loss/decrease of smell and/or taste (25%), muscle ache (22%), and shortness of breath (19%).
“Given the high prevalence of long COVID among HCWs, policymakers need to assess the impact of long COVID on the workforce in their areas and prioritize care for this condition,” the authors wrote. “Additionally, the findings suggest the need for tailored interventions to manage workloads and ensure adequate rest for HCWs affected by long COVID.”
Dental workers also at risk
In a second study, a survey conducted in Germany reveals a 23% rate of long COVID among dental professionals, with higher rates in auxiliary personnel than in dentists. The study is published in Scientific Reports.
The study was based on responses from 267 team members from 186 German dental practices who answered an online questionnaire on vaccination status, confirmed COVID-19 diagnosis, and self-reported long COVID symptoms.
A COVID-19 infection after January 1st, 2021, was reported by 146 (54.7%) participants, of which 33 (22.6%) suffered from long COVID symptoms, the authors said.
There were lower vaccination rates among dental auxiliary personnel compared to dentists (95.9% compared to 84.2%), and the auxiliary personnel (including assistants and hygienists) had higher rates of long COVID compared to dentists.
“Individuals with long COVID symptoms were more often dental assistants (long COVID 48.5% vs. no long COVID 29.2%) or dental hygienists (15.2% vs. 8.0%) than dentists (36.4% vs. 62.8%),” the authors wrote.
Similar to the first study, the most common long COIVD symptoms were exhaustion, fatigue, and lack of concentration. Overall, vaccination seemed to be protective against long COVID in this study.
We observed a 10% difference in the incidence of long COVID between vaccinated and non-vaccinated dental team members.
“We observed a 10% difference in the incidence of long COVID between vaccinated and non-vaccinated dental team members,” the authors wrote. “However, due to the small number of subjects with long COVID, we can not conclusively determine if unvaccinated dental healthcare personnel are more susceptible to suffer from long COVID or experience more severe symptoms.”

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