Is COVID-19 Herd Immunity Influenced by Population Densities of Cities?

Abstract

The objective of the current study is to compare between densely and sparsely populated cities in the context of herd immunity against the SARS-CoV-2 virus. The sample refers to 46 (45) densely populated (sparsely populated) Israeli cities and towns, whose population density is below (above) the median of 2388 persons sqkm, covering above 64.3% of the entire Israeli population. Findings suggest, on the one hand, a higher projected scope of morbidity per 10,000 persons in sparsely populated cities with zero prevalence of vaccination (37.79 vs. 17.61 cases per 10,000 persons). On the other hand, the outcomes propose a steeper drop in the scope of COVID-19 morbidity with higher vaccination rates in sparsely populated cities. Findings suggest that in terms of vaccination campaigns, below 60–70 percent vaccination rates, more efforts should be invested in sparsely populated cities. If, however, the 70 percent threshold is achieved, a further reduction in the scope of morbidity would require a higher (lower) rate of vaccination in densely populated (sparsely populated) cities.

Urban public health emergencies and the COVID-19 pandemic. Part 1: Social and spatial inequalities in the COVID-city

“…In contrast, the 1918 Spanish flu pandemic – which affected around 25% of the world’s population – occurred when less than one in five people lived in cities: moreover, the highest mortality from Spanish flu was in rural communities, with those in urban settlements seemingly enjoying a degree of inherited immunity thanks to exposure to previous waves of communicable disease and the H1N1 virus that caused Spanish flu. As such, the consensus that the improvement of sanitation and hygiene, underpinned by social distancing, can reduce the transmission of COVID-19 and future viruses, needs to be juxtaposed with the view that acquired immunity might rely on repeated exposure to the virus, with ‘herd’ immunity sometimes depicted as a more cost-effective, if contentious, alternative to vaccine-acquired immunity (see Arbel et al, 2022).…”