Journal Information
Download PDF
More article options
Brief communication
DOI: 10.1016/j.bjid.2020.08.003
Open Access
Uncorrected Proof. Available online 14 September 2020
COVID-19 in health care workers in a university hospital during the quarantine in São Paulo city
Klinger Soares Faíco-Filho
Corresponding author

Corresponding author at: Rua Napoleão de Barros, 627 - Vila Clementino, 04024-002 São Paulo, Brazil.
, Joseane Mayara Almeida Carvalho, Danielle Dias Conte, Luciano Kleber de Souza Luna, Nancy Bellei
Universidade Federal de São Paulo, São Paulo, SP, Brazil
Article information
Full Text
Download PDF
Figures (1)
Tables (1)
Table 1. COVID-19 among health care workers in Hospital São Paulo.

Health care workers (HCW) are at a higher risk of being infected in their workplace. We diagnosed COVID-19 by RT-PCR for SARS-CoV-2 among 466 HCW from Hospital São Paulo who presented with influenza-like illnesses or any clinical suspicion of COVID-19 and analyzed the type of exposure and hospital occupation of 169 positive cases (36%). Data of HCW household locations were also obtained. Logistic workers had the highest rate of SARS-CoV-2 (p = 0.002), but nurse technicians had the highest rate among those reporting routine contacts with patients (p = 0.001). Doctors presented the lowest rate of infection, although living in most affected districts (p < 0.001). Policies and adequate training for all hospital employees may improve the prevention of the infection among all health care service categories.

Health care workers
Full Text

On March 11th, WHO declared COVID-19 as a pandemic. Two days after, the first case of COVID-19 was confirmed at Hospital São Paulo, a large university hospital in São Paulo city. On March 23rd, a quarantine was declared by the local authorities.1 SARS-CoV-2 infections increased in many metropolitan areas even with social distancing measures.

Health care workers (HCW) are at a higher risk of being infected in their workplace and at the community level as the outbreak expands in urban areas. We diagnosed COVID-19 among HCW and analyzed their type of exposure and household location in the city.2

From March 22nd to April 22nd, during the quarantine in the city, HCW from Hospital São Paulo presenting with influenza-like illnesses or any clinical suspicion of COVID-19 were evaluated at the HCW Medical Assistance Service as part of a routine surveillance after the pandemic was declared. Of note, 144 patients were hospitalized with a COVID19 diagnosis during this period.

Nasopharyngeal swabs were collected, immediately transported to the virology laboratory, and were tested by a specific polymerase chain reaction method for SARS-CoV-2 according to the CDC USA protocol.

HCW were categorized based on the type of exposure to patients (daily contact or not) and the hospital job occupation. Logistic workers included laundry, cleaning services, and security staff. Data regarding the HCW’ household locations were also obtained and analyzed according the residential administrative districts. Fig. 1 shows the general population of confirmed COVID-19 cases in São Paulo city, and the green areas with 120–238 cases were considered the most affected, having the highest risk of SARS-COV-2 transmission.

Fig. 1.



Statistical analysis: Student t-test, contingency table analysis calculated using chi-square or Fisher’s exact test was used, and a p-value <0.05 was considered statistically significant.

A total of 466 swabs for COVID-19 were analyzed, and 36% (n = 169) were Positive for SARS-CoV-2. The median age was 39.2 years and 71.8% were females (335/466). The positivity rate of each category according to exposure and job description is shown in Table 1.

Table 1.

COVID-19 among health care workers in Hospital São Paulo.

Daily contacts  Total (n = 466)  Positive (n = 169) (n/%)  Household high-risk area (n/%)  All areas 
Nurse technician*  128  57 (44.0)  6 (16.2)  37 
Nurse  54  16(29.0)  – 
Doctor  107  26(24.2)  13 (76.4)*  17 
Laboratory personnel  14  4(28.5)  – 
Physiotherapist  16  4(25.0)  2 (50%) 
Phonoaudiologist  2(66.6)  – 
No contacts
Administrative staff  90  28(31.1)  4 (28.5%)  14 
Logistic workersa,*  27  17(62.9)  4 (26.6%)  15 
Othersb  27  15(55.5)  2 (28.5%) 



Laundry, cleaning services, security staff.


Dentist, pharmacist, radiologist.


p-Value <0.05.

Logistic workers had the highest rate of SARS-CoV-2 infection (p = 0,0029), but nurse technicians had the highest rate among those reporting daily contact with patients (p = 0.0010).

We also analyzed the household geographic distribution of the HCW positive cases in the administrative districts of São Paulo. Fig. 1 shows different COVID-19 rates in the general population according to the City Health Office data distributed in the city and also the 106 out of 126 HCW positive cases distributed by household locations.3 Nineteen of these HCW lived near the hospital’s neighborhood, the most affected district by the outbreak. The available location of 106 HCW diagnosed with COVID-19 and their household locations are presented in Table 1. Doctors presented the lowest rate of infection although living in most affected districts (p < 0.001).

COVID-19 transmission among HCW is a common fact; China, Spain, and the USA have also observed a great number of affected HCW.4,5 Our COVID-19 study was conducted in a university hospital of a district in São Paulo with a high rate of confirmed cases during the quarantine.

Considering routine daily contact, nurse technicians were infected the most, probably due to many opportunities for exposure during their shift, although they had received training on the use of personal protective equipment. Unexpectedly, we found that the highest rate of infection was among personnel who had no direct patient contact. Logistic workers were less trained and/or unaware of the risks of COVID-19 transmission at the hospital. Quite often, administrative technicians and logistic workers are not provided with adequate training and personal protective equipment. In this sense, it is essential to implement health policies for professionals who do not have routine contact with patients.

Infection of HCW in the community cannot be ruled out, since many HCW live in high affected districts and many of the positive cases live in the hospital’s neighborhood. Liu et al. in their study about the aerodynamics of SARS-CoV-2 reported high levels of airborne RNA in areas prone to crowding, probably due to infected carriers in the crowd.6 However, logistic workers’ household locations were not significantly associated with the most affected COVID-19 districts (p > 0.05).

Limitations of this study include small sample size, short study time frame, and lack of some HCW data. Facilitating testing of symptomatic professionals, creating sick leave policies that are non-punitive, flexible, and consistent with public health guidance, and providing adequate training and protective equipment could improve the prevention of infection transmission to employees.

Conflicts of interest

The authors declare no conflicts of interest.

Chow EJ, Schwartz NG, Tobolowsky FA, et al. Symptom screening at illness onset of health care personnel with SARS-CoV-2 infection in King County, Washington. JAMA. Published online 17 April 2020.
Z. Wu, J.M. McGoogan.
Characteristics of and important lessons from the coronavirus disease 2019 (COVID-19) outbreak in China: summary of a report of 72 314 cases from the Chinese Center for Disease Control and Prevention.
JAMA, 323 (2020), pp. 1239-1242
W.J. Guan, Z.Y. Ni, Y. Hu, et al.
Clinical characteristics of coronavirus disease 2019 in China.
Y. Liu, Z. Ning, Y. Chen, et al.
Aerodynamic analysis of SARS-CoV-2 in two Wuhan hospitals.
Copyright © 2020. Sociedade Brasileira de Infectologia
The Brazilian Journal of Infectious Diseases

Subscribe to our newsletter

Article options
Cookies policy
To improve our services and products, we use cookies (own or third parties authorized) to show advertising related to client preferences through the analyses of navigation customer behavior. Continuing navigation will be considered as acceptance of this use. You can change the settings or obtain more information by clicking here.