COVID-19 mortality rates in South America related to environmental factors

ABSTRACT

The COVID-19 pandemic started its outbreak in South America in mid-February 2020, causing hundreds of thousands of deaths within a period of 8 months. This ecological study aimed to investigate whether environmental factors like air quality and climate could explain the variability in COVID-19 mortality rate across 36 South American cities spanning different climate regimes. The cities’ climate and air pollution background were characterised using daily data from surface weather stations and tropospheric column NO₂ from OMI (Ozone Monitoring Instrument). Results indicate a drop in NO₂ concentrations in six metropolitan areas in the first month of the epidemics, following the mobility restrictions. Temperature and NO₂ exposure were positively associated with deaths by COVID-19, with mortality rate ratios (MRR) of 1.25 (95% CI 1.20–1.30) and 1.02 (95% CI 1.01–1.03), respectively, in the 100^th epidemic day. The positive association between temperature and deaths related to COVID-19 suggest that the likely protective effect of temperature on virus spread was overwhelmed by the influence of socioeconomic conditions, access to health care, cultural aspects and effectiveness of social distancing policies.

KEYWORDS:

• COVID-19
• air quality
• climate
• mortality

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplementary material

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