Factors Associated with SARS-CoV-2 Infection among Oral Health Team Professionals

Factors associated with SARS-CoV-2


Introduction
SARS-CoV-2, the virus discovered in December 2019 in Wuhan, China, is the pathogen responsible for the Coronavirus Disease of 2019 .In March 2020, COVID-19 was categorized by the World Health Organization as the pandemic with the largest impact in the current century.It has introduced challenges to the routines of health professionals [1,2].
As the respiratory tract is the principal form of infection by SARS-CoV-2, the risk of transmission becomes extremely high in clinical dental practice.Besides close contact between the professional and the patient, the routine work process includes the use of equipment that disperses aerosols of potentially contaminated body fluids into the environment [3][4][5][6][7].
Hence, strict biosafety recommendations were published during the pandemic [8,9], including the suspension of elective services, avoiding the use of devices that generate aerosols, a strict use of personal protection equipment (PPE) and the inclusion of additional protection, such as N95/NFFP/or similar masks and face shields [4][5][6].However, besides the clinical occupational risk, socioeconomic factors can increase the risk of SARS-CoV-2 infection and deserve greater attention [10].
Studies about SARS-CoV-2 infection in odontology [4,6,7] have been directed at dental surgeons (DS), and little is known about the realities of dental hygienists (DH) and dental assistants (DA), mainly working in essential services such as primary health care (PHC).Hence, the objective of this study was to analyze the prevalence of and the factors associated with the SARS-CoV-2 disease among oral health teams (OHT) in the public dental health system in 2020.

Study Design
A cross-sectional web survey was conducted in September 2020 with OHT professionals at Clinics I and II of the 11 public health clinics (HC) under the responsibility of the Brazilian Israeli Charitable Society Albert Einstein Hospital (Sociedade Beneficente Israelita Brasileira Hospital Albert Einstein), in the south zone of the city of São Paulo, SP, Brazil.

Sample and Data Collection
Dental surgeons (DS), dental assistants (DA), and dental hygienists (DH) were included in the study.
Those who were on leave during the data-gathering period of the study were excluded.
A questionnaire was created on a digital platform and sent via institutional email to each subject in the sample, obtained from the human resources department.The questionnaire contained 32 questions about sociodemographic, work, and behavior factors.The data about SARS-CoV-2 infection was confirmed through RT-PCR exams.
The dependent variable of the study was the diagnosis of SARS-CoV-2 infection, dichotomized into: "confirmed" and "unconfirmed".The independent variables were divided into three categories: 1. Sociodemographic: sex (male or female); age (in years); education level (high school/technical school or college/post-graduate); household income (determined by the median income); relation of the number of inhabitants per room (less than 1, or greater than or equal to 1); comorbidities (yes or no); and having a relative diagnosed with COVID-19 (yes or no).
The general prevalence of SARS-CoV-2 infection was 20.3% and by job category, DS (3.8%), DH (30.0%), and DA (33.3%).In addition, SARS-CoV-2 infection was associated with professionals with a lower education level (p=0.011) and lower salary level (p=0.027)(Table 1).Most participants were were dental surgeons (40.6%), used private transportation to go to work (64.1%), and commuted for up to 1 hour (62.5%).During the pandemic, the professionals were not reallocated to another service (84.4%), nor did they change their duties (70.3%).They did not feel safe to carry out their job (51.6%) and were afraid of SARS-CoV-2 infection (85.9%).In relation to the information about COVID-19, 96.9% felt informed, 92.2% received information from the institution, and 98.4% took one or more e-learning courses about COVID-19.SARS-CoV-2 infection was associated with DAs and DHs (p=0.025), the use of public transportation to commute to work (p=0.009), and no access to information on the internet (p=0.027)(Table 2).PPE was made available by the employer for more than 80.0% of all the OHT professionals surveyed.
Hair nets, glasses, and disposable gowns were the most available PPE, and face shields (15.9%) were the least available (Figure 1).Regarding the condition/quality of the PPE, glasses were the highest rated (100.0%) and face shields were the lowest rated (30.5%) (Figure 2).

Discussion
The prevalence of SARS-CoV-2 infection among oral health professionals was high, and well above the general population [11,12], and produced results that were discrepant with studies done with DSs in Italy (0.25%) [13] and the United States (16%) [7].This fact may be due to methodological differences, the time of the survey, and the phase of the epidemic curve in each country and the locally adopted preventative measures.
It should be taken into consideration that in São Paulo, SP, at the time of the study, the Municipal Health Secretariat only allowed emergency clinical dental procedures at the SUS (Sistema Único de Saúde) public health network [13].Thus, income inequalities can play an important role in the impact of COVID-19 in Brazil, through these contextual effects [14][15][16], even among health professionals.
The greater levels of SARS-CoV-2 infection among oral health professionals at the technical level, i.e., with lower levels of education, corroborate current findings [17][18][19].The education level influences knowledge, behaviors, and appropriate practices related to preventing infection in the work environment and outside of it [20,21].However, the work process in this context must also be considered: two people are recommended to reduce the amount of working time and the risk in the procedure.This increases the risk of similar aerosols.The technical team also washes and sterilizes the materials and cleans the room [9].Thus, they can be more prone to SARS-CoV-2 infection [22][23][24].
The use of public transportation like the bus, train, and metro was associated with SARS-CoV-2 infection.Thus the method of transportation becomes a work factor as important as the clinic environment itself.In this sense, health services need to rethink their professionals' methods of transportation, which put their own health and that of their colleagues and users at risk.Different from the health services that adopted the use of PPE and strict biosafety protocols [4][5][6][7] to reduce the risks of infection, the precautions taken on public transportation depend on the actions of public entities and the adherence of the users [25,26].This fact is further compounded in studies done in a cosmopolitan city like São Paulo.
As found in the literature [13,[24][25][26][27], the health professionals feel informed about COVID-19; they have access to the necessary PPE and evaluated it as being of good quality.However, they showed a high prevalence of feeling unsafe, afraid, and anxious about the risk of infection, as shown in other studies [21,23].
This factor can explain the high levels of adherence to adopting preventative measures, for example, the use and a more careful removal of PPE, which culminates in the decrease of infection [20,21,28].
Regarding limitations, this study excluded people who were on leave, which could have excluded people with symptoms and no diagnosis.However, it should be highlighted that all the participants of this study are on strategic family health teams working in public health clinics, explaining why they work 40 hours per week and receive good salaries as compared to other Brazilian cities.This is why they nearly always work exclusively at this job, which can reduce the understanding about the possibility of infection at other workplaces.

Conclusion
The prevalence of SARS-CoV-2 was high among oral health professionals in primary health care

2 .
Work: job category (DS, DA, or DH); private (car, bicycle, on foot) or public (bus, metro, train) method of transportation used to commute and the commute time (up to 1 hour or over 1 hour); PPE availability and quality.3. Behavior: safety (yes or no); fear of infection (yes or no); feels informed about COVID-19 (yes or no); sources of information (institutional, TV, internet, others).Data Analysis The data was analyzed using IBM SPSS Statistics for Windows, Version 21.0 (IBM Corp., Armonk, NY, USA).Descriptive (absolute and relative frequencies) and inferential analyses (chi-squared or Fisher's exact test) (p<0.05) were performed.Ethical Clearance The study was approved by the Committee of Ethics in Research of the Municipal Health Secretariat of São Paulo (Protocol No. 4.363.698).

Figure 1 .
Figure 1.Distribution of the availability of personal protection equipment (PPE) for oral health team professionals.São Paulo-SP, 2020.

Figure 2 .
Figure 2. Distribution of the condition/quality of personal protection equipment (PPE) available to the oral health team professionals.
-2 infection, in this study, was associated with the technical job category (DH and DA), in people with lower income, lower education level, and who used public transportation to commute to work.

(
PHC) and was associated with sociodemographic factors, such as a lower salary and education level, and work factors, such as the category of technical professional and the use of public transportation.The professionals showed a high prevalence of ongoing education, mainly e-learning, and the availability of high-quality PPE.In spite of feeling prepared for the work process during the COVID-19 pandemic, they felt unsafe, afraid, and anxious about the risk of infection.

Table 2 . Work and behavior factors associated with SARS-CoV-2 infection among oral health team professionals.
*Fisher's exact test (p<0.05).