As on May 30, 120 days since the first case was reported in Kerala, the number of cases in India has shot up to 1,65,345 and deaths to 4,707. The number of cases reported across the world stands at 5.8 million, and India has the ninth highest number of cases reported. This despite the country being in a nationwide lockdown since March 25.
Even as nearly 66% of the Indian population is in rural areas, the large majority of cases reported so far are from a few cities. The airborne route of transmission, primarily droplet transmission, and high population density seen in urban areas provide a fertile ground for the virus to spread. The high prevalence of comorbidities in people living in urban areas is responsible for the higher deaths.
Interactive map of confirmed coronavirus cases in India |State-wise tracker for coronavirus cases, deaths and testing rates
Dr. Ashish Awasthi from the Public Health Foundation of India (PHFI), Gurgaon, and Dr. Dileep Mavlanka, Director of the Indian Institute of Public Health, Gandhinagar, found 20 of 739 districts accounting for over 67% of cases and over 77% mortality. They reported the findings in a blog posted on BMJ Global Health. The blog post is not peer-reviewed. They used COVID-19 data retrieved from covid19india.org, a crowdsourced platform for COVID-19 data, Census data of 2001 and 2011 to extrapolate urban population, population density and population above 60 years, and finally, the 2015-16 National and Family Health Survey data for district level comorbidity information.
They found nearly 51% cases and over 53% deaths were from just five cities — Mumbai, Delhi, Ahmedabad, Chennai and Thane. All cities that have reported more cases have a population density of 1,036 to 28,220 persons per sq. km, while 15 out of 20 hotspot districts have more than 50% urban population.
In Mumbai, which has the highest case burden, four people sleep in a single room in more than 31% households, they note. Many studies have shown that most virus spread occurs in enclosed spaces and with prolonged exposure, particularly in households. This seems to be particularly true in the case of Mumbai.
However, India has a low case fertility rate and the fewer deaths per million population. With 3.4 deaths per million, India has one of the lowest figures compared with other countries such as Belgium (805), Italy and the U.K. (545) and France (437). Totally, 130 countries have death per million more than the Indian average, they note.
However, the picture changes completely when deaths per million in 10 of top 20 districts are taken into consideration. With 87 deaths per million, Ahmedabad has a greater number of deaths than any other city. Mumbai is close behind with 85 deaths per million. The number of deaths per million in these two cities is more than 25 times the national average. In comparison, Kolkata has 43.1 deaths per million population. It is surprising that Indore (28) and Pune (24.2) have more deaths per million than Chennai (19.8).
Some of reasons for higher mortality figures in these cities could be late detection of cases, lack of timely access to healthcare facilities or larger spread of the virus in the community. The first death in Gujarat was reported from Ahmedabad on March 22 when only 18 cases were reported. Gujarat also has the second highest case fatality ratio in the country after West Bengal. In Chennai, according to media reports, on March 28 when 12 deaths were reported, apparently 50% of deaths happened within 48 hours of a positive test result.
“In our analysis, high urban proportion and population density were significantly correlated with the COVID-19 burden in districts having the highest burden of COVID-19. It appears COVID-19 is spreading only in a limited number of large cities/districts with high population density. A tiny proportion of the cases are in rural areas or small cities and towns,” they write.