
==== Front
Lancet Reg Health Am
Lancet Reg Health Am
Lancet Regional Health - Americas
2667-193X
Elsevier

S2667-193X(24)00196-0
10.1016/j.lana.2024.100869
100869
Comment
Health inequities in COVID-19: insights from Rio de Janeiro's marginalised communities
Cerqueira-Silva Thiago thiago.silva@lshtm.ac.uk
ab∗
Pescarini Julia M. a
a Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, UK
b Instituto Gonçalo Moniz, Fiocruz, Salvador, Bahia, Brazil
∗ Corresponding author. Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London. UK. thiago.silva@lshtm.ac.uk
16 8 2024
9 2024
16 8 2024
37 10086925 6 2024
15 7 2024
6 8 2024
© 2024 The Author(s)
2024
https://creativecommons.org/licenses/by-nc-nd/4.0/ This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
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pmcDespite the global impact of COVID-19, there has been a lack of research focusing on the most vulnerable communities worldwide, which have been disproportionately affected both by the disease's burden and its economic consequences.1 In Brazil, approximately 8% of the population, or 16 million people, live in slums, mostly located in major cities and with a large population working in the informal sector.2 In this issue of The Lancet Health—Regional Americas, Coelho et al.3 and Azambuja et al.4 investigated COVID-19 household transmission and risk factors for long COVID, respectively, in some of Rio de Janeiro's marginalised communities.

Coelho et al. enrolled 2024 people from nearly 600 households in Complexo de Manguinhos (ranked 122nd out of 126 neighbourhoods in Rio de Janeiro's Human Development Index) between November 2020 and 2021, before the Omicron variant emerged in Brazil. To evaluate the chain of COVID-19 transmission, they collected a variety of socioeconomic variables and found an increased risk of transmission in overcrowded households with lower incomes, as well as lower transmission among people who had received at least one dose of a COVID-19 vaccine. Importantly, they suggest that the well-established conditional cash transfer programme (Bolsa Família Programme–BFP) was associated with lower extra-household transmission, whereas receiving Auxílio Emergencial did not show the same association.

Similarly, Azambuja et al. recruited 710 people from Complexo da Maré (ranked 123rd out of 126 neighbourhoods in Rio de Janeiro's Human Development Index), between November 2021 and May 2022 to assess factors associated with long COVID. In this study, they defined long COVID as symptoms lasting more than three months, and the study sample was composed of people infected with Delta and Omicron variants, which can have different clinical profiles.5 Their overall findings are consistent with the literature, identifying female sex and comorbidity as risk factors for long COVID, and vaccination as a protective factor.6,7

Both studies confirmed the beneficial role of COVID-19 vaccines in reducing COVID-19 transmission and lowering the risk of developing long COVID, highlighting the importance of vaccines as essential tools to protect communities both individually and as a public health measure. However, despite Brazil's universal and well-established immunisation programme, many individual risk factors likely influence susceptibility to COVID-19 infection and its complications.

People living in slums frequently exhibit wide disparities in income, working conditions, and access to healthcare. Coelho et al. demonstrated these heterogeneities in the risk of COVID-19 transmission based on poverty indicators. They analysed a sample in which almost one-third were recipients of BFP, who are people experiencing poverty or extreme poverty, and who are usually included in a broader context of social and health assistance that comprises the conditionalities of the programme. As a result, Coelho et al.'s findings could also be explained by BFP's improved connection to primary health care, in contrast to the unconditional cash transfer of Auxílio Emergencial,8 which was granted to all people who were vulnerable to the effects of COVID-19, including informal workers, micro-entrepreneurs, and BFP recipients. Moreover, the study found an increased risk of extra-household transmission among those using public transport, which was more prevalent among the poorest study participants. These results were expected due to the excessive and widespread reduction in public transport fleets across major cities in Brazil, ignoring the higher demand for public transport in urban peripheries compared to central areas, resulting in frequently overcrowded transport.9,10

Azambuja et al. also introduced the links between poverty and COVID-19 sequelae, suggesting that lower education was associated with lower quality of life and a higher prevalence of long COVID. However, the inclusion of detailed socioeconomic data could have improved their findings. During the COVID-19 pandemic, vulnerable communities faced limited healthcare access and economic insecurity,11 exacerbating the impact of COVID-19 and increasing the risk of developing long COVID due to difficulties in taking extended breaks from work, resulting in an inability to adequately rest after COVID-19, a known risk factor for long COVID.7 Further investigation into the relationship between socio-vulnerability, access to healthcare, and long COVID should be undertaken.

In the context of historically marginalised populations in Brazil, the government's response to future epidemics must combine our strong immunisation programme with comprehensive policies that sensibly tackle the socioeconomic determinants of health and effectively reduce health disparities.

Contributors

TCS wrote the initial draft of the manuscript. JP further revised the manuscript.

Declaration of interests

The authors declare no competing interests.
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References

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