Data | Lower COVID-19 fatality rate in rural areas not necessarily due to lower share of co-morbidities among rural population

People wait in a queue to register their names to have their nasal swab samples taken to test for COVID-19 in Jammu. (Source: AP)

India’s COVID-19 Case Fatality Rate (CFR) has been on a decline. The country’s CFR (deaths/cases) reduced from 2.97% on June 30 to 1.64% on September 15.

One reason could be the fact that, despite a rapid rise in rural cases in recent months, a similar increase in rural deaths was not observed. Is the CFR lower in rural areas as the share of population with co-morbidities is lower compared to urban areas?

A district-wise analysis shows that this is not necessarily so. The relation between CFR and diabetes prevalance in rural areas is mild and somewhat negatively correlated. This lends credence to the argument that there is more to low CFR in rural areas, perhaps explained by lower reporting of deaths.

Persistently low rural CFR

The CFR in rural and semi-rural districts has always remained lower than in urban and semi-urban districts. Notably, despite a case surge in rural areas in August and September, the rural CFR continued to remain low.

Data | Rural CFR chart 1

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Lower rural co-morbidities

The share of male population* with co-morbodities such as diabetes and hypertension is higher in urban areas than rural areas, data from NFHS-4 (2015-16) show.

Data | Rural CFR chart 2 

Relative to diabetes

The chart plots the % of men with high blood sugar levels against the CFR in rural and semi-rural districts. There is a mild negative correlation between the indicators. Thus, counter-intuitively, the CFR was in fact lower in many districts where the % of men with high sugar levels was higher.

Data | Rural CFR chart 3 

Relative to hypertension

The chart plots the % of men with ‘slightly above normal’ hypertension levels against the CFR in rural and semi-rural districts. There is a very weak positive correlation between the two indicators, showing that the CFR is not necessarily linked to prevalence of hypertension.

Data | Rural CFR chart 4 

*Note: Since the combined indicator was unavailable with the NFHS, numbers for men were chosen for representation. However, a similar analysis for women concurred with the above conclusions. Analysis was also done for varying levels of sugar and BP and gave similar results.