Dear Editor,
Brazil faces a severe economic, social and politic crisis, and consequently is one of the leading countries with the greatest number of cases and deaths due to COVID-19 caused by SARS-CoV-2.1 Despite infectious diseases affect mainly socially and economically vulnerable people,2 there is few data about the frequency of SARS-CoV-2 infection among them. Therefore, between July and October 2020, we investigated the prevalence of SARS-CoV-2 among recyclable waste collectors, homeless people, immigrants and refugees, LGBTQ people, sex workers, people using illicit drugs, and patients with HIV in Goiânia, a large city in Midwest Brazil.
All participants were interviewed, and samples of oropharynx and nasopharynx were collected for the detection of RNA-SARS-CoV-2. RNA extraction from SARS-CoV-2 was performed using the QIAamp Viral RNA Mini Kit (Qiagen, Maryland, USA), and real-time quantitative polymerase chain reaction (RT-PCR) was performed using AgPath-IDTM One-Step RT-PCR Reagents (Thermo Fisher Scientific, Massachusetts, USA). The assays were performed using probes from the 2019-nCoV kit (Integrated DNA Technologies, San Diego, USA).
This project was approved by the Research Ethics Committee (process no. 4145237).
A total of 517 individuals were recruited and 510 agreed to participate in the study (Table 1 ). The median age was 33 years (interquartile range [IQR]: 22 years), and 57.8% were male. The majority of individuals (79.2%) were non-white. The median number of years of formal education was 10 (IQR: 6), and the monthly income was approximately 222 US$ (IQR: 198).
Table 1.
RNA-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among 493 vulnerable individuals in Midwest region.
| Characteristic | n | RNA-SARS-CoV-2 (+) | % |
|---|---|---|---|
| Age (median; IQR) | 493 | 29 (15) | |
| Education (years) (median; IQR) | 493 | 12 (5) | |
| Monthly income (US$) (median; IQR) | 493 | 213 (202) | |
| Population subgroup | |||
| LGBTa | 79 | 12 | 15.2 |
| Recycled waste collectors | 145 | 23 | 15.9 |
| Immigrants/refugees | 121 | 57 | 47.1 |
| Homeless | 131 | 3 | 2.3 |
| Sex workers | 4 | 0 | |
| Illicit drug users | 10 | 0 | |
| PLWHIVb | 6 | 0 | |
| Gender | |||
| Female | 208 | 41 | 19.7 |
| Male | 285 | 54 | 18.9 |
| Color | |||
| White | 104 | 22 | 21.2 |
| Non-white | 389 | 73 | 18.8 |
LGBT: lesbian, gay, bisexual, transexual; PLWHIV: people living with HIV.
IQR: interquartile range.
In 17 samples, the results of RT-PCR were inconclusive. RNA-SARS-CoV-2 was positive in 95/493 (19.3%; 95% CI: 16.0–23.0) samples. The frequency of SARS-CoV-2 positivity was higher among immigrants/refugees (47.1%), followed by recycled waste collectors (15.9%) and LGBT (15.2%) subgroups (Table 1).
Currently, Brazil is the epicenter of the COVID-19 pandemic in Latin America1 and, as observed in other contagious diseases, socially and economically vulnerable populations are disproportionately affected.2 We detected RNA-SARS-CoV-2 in samples of 19.3% (95% CI: 16.0–23.0) of the individuals, and this increased to 37.3% (95% CI: 27.7–48.1) among those who reported with at least one COVID-19 sign and symptom. This is close to that observed among symptomatic Brazilian healthcare workers in São Paulo (42.4%; 95% CI: 36.9–48.1),3 a regional COVID-19 epicenter. It is noteworthy that healthcare workers are frontline professionals in coping with the COVID-19 pandemic.
In this study, immigrants were the groups most affected, following by LGBT and recycled waste collectors. Therefore, the COVID-19 pandemic represents an additional challenge to be overcome by them, considering that unemployment, precarious housing, and food conditions have intensified their social, economic, and health difficulties, mirroring the existing social inequality. Thus, face masks, water and soap/sanitizer for hand hygiene, social distancing, and more recently the access to COVID-19 vaccine are challenges for these individuals.
The high frequency of COVID-19 reinforces the priority of this population for vaccination against SARS-CoV-2 in Brazil, as well as the necessity to improve the tracking of new cases, such as expanded testing and the creation of useful public policies aimed at vulnerable populations.
Funding/support statement
This study was funded by the National Council on Scientific and Technological Development/Conselho Nacional de DesenvolvimentoCientífico e Tecnologico (CNPq).
And Foundation for Research Support in Goias/Fundaçao de Amparo a Pesquisa de Goiás.
Declaration of competing interest
None.
References
- 1.World Health Organization . 8 July 2021. WHO coronavirus disease (COVID-19) dashboard.https://covid19.who.int/ [Internet].Data last updated: 5:52pm CET. [cited 2021 Jul 8]. Available from: [Google Scholar]
- 2.Engels D., Zhou X. Neglected tropical diseases: an effective global response to local poverty-related disease priorities. Infect Dis Poverty. 2020;9(1):10. doi: 10.1186/s40249-020-0630-9. [Internet] [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Buonafine C.P., Paiatto B.N.M., Leal F.B., de Matos S.F., de Morais C.O., Guerra G.G., et al. High prevalence of SARS-CoV-2 infection among symptomatic healthcare workers in a large university tertiary hospital in São Paulo, Brazil. BMC Infect Dis. 2020;20(1):917. doi: 10.1186/s12879-020-05662-8. https://bmcinfectdis.biomedcentral.com/articles/10.1186/s12879-020-05662 [Internet] [cited 2021 mar 15]. Available from: [DOI] [PMC free article] [PubMed] [Google Scholar]