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Abstract The COVID‐19 outbreak in 2020 resulted in rapidly rising infection rates with high associated mortality rates. In response, several epidemiological studies aimed to define ways in which the spread and severity of COVID‐19 can be curbed. As a result, there is a steady increase in the evidence linking greenspaces and COVID‐19 impact. However, the evidence of the benefits of greenspaces or greenness to human wellbeing in the context of COVID‐19 is fragmented and sometimes contradictory. This calls for a meta‐analysis of existing studies to clarify the matter. Here, we identified 621 studies across the world on the matter, which were then filtered down to 13 relevant studies for meta‐analysis, covering Africa, Asia, Europe, and the USA. These studies were meta‐analyzed, with the impacts of greenness on COVID‐19 infection rate quantified using regression estimates whereas impacts on mortality rates were measured using mortality rate ratios. We found evidence of significant negative correlations between greenness and both COVID‐19 infection and mortality rates. We further found that the impacts on COVID‐19 infection and related mortality are moderated by year of publication, greenness metrics, sample size, health and political covariates. This clarification has far‐reaching implications for policy development toward the establishment and management of green infrastructure for the benefit of human wellbeing.

Whilst the human population is declining in some parts of the world, the African population is growing tremendously despite recurrent epidemics and global pandemics. Since African population density is higher where plant diversity is high and 80% of the African population relies on herbal medicine, the resilience of the African population in the context of disease outbreaks may be linked to a strong tie of Africans with nature. However, is the potential effect of such a tie well established in the scientific discourse? To investigate this question, we followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We found that very few studies tested the relationships between greenspaces and human health conditions on the continent. Out of the 54 African countries, studies that investigate the link between greenspaces and health are from only six countries and the earliest study was published only in 2013, indicating the recency of research on this subject in Africa. These few studies, not only report mixed findings but are also heterogeneous in terms of their design (longitudinal versus cross-sectional), the choice of predictors and health outcomes as well as how these variables are measured. This review showed that there is a paucity of studies on the greenspace and human health nexus on the continent, making it difficult i) to establish or generalise the relationships between greenspaces and human health conditions in Africa, and ii) to investigate the mechanisms driving the effects of nature on human wellbeing in Africa. To fuel interests and guide future research on the continent, the rate of knowledge generation needs to be rapidly increased, and this requires first the identification of current barriers. Second, we need to update curricula at African universities to include statistical modelling which can fuel interest into more hypothesis-driven (rather than just descriptive) studies.