Living in a busy city doesn’t increase your chances of getting Covid-19, but overcrowding does, a new study reveals.
Researchers analyzed cases in Tehran, Iran, one of the pandemic’s early epicenters, using data from AC-19, Iran’s national Covid ‘tracing’ app.
AC-19, which was pulled from Google’s app store last year over alleged concerns about government espionage, tracks positive cases and deaths by geographic location.
After examining the link between density and virus transmission in the city, the researchers found that “density alone cannot be considered a risk factor.”
The experts emphasize the difference between high urban density – a large number of people living in an urbanized area – and overpopulation.
Pictured, screenshots from the AC-19 mobile app. The right figure shows the state of the pandemic distribution at the city level and the left one shows the situation at the national level. The density alone did not explain the geographic distribution pattern of confirmed Covid-19 cases and deaths in Tehran’s 22 municipal districts
High urban density is a large number of people living in an urbanized area.
Researchers emphasize the difference between urban destination and overpopulation.
“What causes the spread of infectious diseases during a pandemic is overpopulation, which can occur even in low-density districts,” said author Amir Reza Khavarian-Garmsir of the University of Isfahan.
Overpopulation diminishes the ability to distance themselves socially, while high urban density does not necessarily.
“ What drives the spread of infectious diseases during a pandemic is overpopulation that works differently from density and can also occur in low-density neighborhoods, ” the team said in their paper, published in Sustainable cities and society
As a result, metropolitan areas and densely populated zones may also be safe during the pandemic, as density alone cannot be considered a risk factor for Covid-19.
The authors of the study, from Hiroshima University in Japan and the universities of Tehran and Isfahan in Iran, conducted the analysis during the first months of the pandemic.
The data set consisted of the number of confirmed cases up to April 4, 2020 and June 27, 2020 and deaths up to June 27, 2020.
The researchers assessed whether certain variables affected infection rates in Tehran’s 22 districts and approximately 8.6 million residents.
The geographic location of Tehran and Iran and the level of income in Tehran’s 22 municipal districts. Images taken by Statistical Center of Iran (2016) authors and Google Satellite images
They used ‘structural equation modeling’ (SEM), which uses multiple factors to indicate the influence of unobservable variables, such as the likelihood of following public health recommendations, along with measurable factors, such as easy access to medical facilities.
Density alone could not explain the geographic distribution pattern of confirmed Covid-19 cases and deaths in Tehran’s 22 municipal districts, they found,
However, responsible civic behavior is still needed to combat the pandemic in densely populated urban environments to avoid overpopulation.
They also found that the demographic structure of a population – age, social and economic class, access to resources – has far more impact than simply how dense a population is.
The death rate was higher in districts with a higher proportion of older people, while a car owner or someone with a college degree may also be less vulnerable to the disease, they reveal.
There are some drawbacks to the study, the researchers said, mainly the availability and accuracy of data.
The coronavirus pandemic evolved so quickly in the early months that tracking may not capture the full picture.
Map shows the location of Covid-19 deaths on June 27 last year in the city of Tehran, Iran
Shortage and cost testing, as well as a relative lack of severe symptoms in children and young adults, may have skewed the number of truly positive cases.
“It may be too early to draw any definitive conclusions, so future research should continue to explore the relationship between urban density and infectious disease transmission patterns,” said study author Nabi Moradpour at the University of Tehran.
The researchers hope their work will help policymakers develop guidelines for the benefit of people in so-called ‘compact cities’ – metropolitan areas.
“The next step is to further investigate the effects of urban density in other contexts,” said study author Ayyoob Sharifi of Hiroshima University.
‘We are also trying to investigate the long-term effects of the pandemic on compact urban development policy.’
IRAN’S CONTACT TRACING APP RETIRED ‘ABOUT SPYING CONCERNS’
According to reports, AC-19, Iran’s national Covid ‘tracking’ app, has been pulled from the Google Play Store due to concerns about espionage.
Google removed the app on March 9, 2020 – about a week before it was released by the Iranian government.
Users accused the Iranian government of using the pandemic to trick citizens into installing the app, one said research by ZDNet
The Iranian government is said to have collected telephone numbers and real-time geolocation data of its citizens.
AC-19 was also developed by Smart Land Strategy, a company that previously built other apps for the Iranian regime, the report said.
However, ZDNet found the software to be free of spyware.
Sources familiar with Play Store policies also said the app was most likely removed due to a misleading claim that it could detect infections.
AC-19 has also been made available through a dedicated website and other third-party app stores.
According to Sharifi et al (2021), more than four million Iranians have installed the application on their smartphones.