A new study from the Center for Disease Dynamics, Economics and Policy sets out indicators that identify the populations at the highest risk for COVID-19 in India. The study appears on the preprint website medRxiv in April 2020.
Since the first case of COVID-19 appeared in India early this year, India closed down flights to and from China, placed travelers suspected to have the disease in quarantine, and eventually announced a complete lockdown on March 24, 2020. However, skepticism is widespread as to the success of the measure in arresting the spread of the virus in the country.
The Current Situation in India
As of April 30, 2020, there were over 34,000 cases and over a thousand deaths in India, and no signs that the spread or the number of cases is decreasing in many parts of the country. Testing is confined to a very small number of cases, at only 0.023 per 1,000 population. This means that in most cases, the disease is going unnoticed and undiagnosed.
Even so, the lockdown, which will have lasted 42 days by May 3, 2020, has reduced the rate of transmission by limiting mobility. However, the challenge will begin with its removal.
In the absence of an effective vaccine or therapeutic strategy, and none on the horizon soon, high-risk populations must be identified in order to take pre-emptive action and reduce the risk of the virus spread and consequent high mortality rates.
How Did the Researchers Identify Vulnerable Groups?
As India stares down the barrel of post-lockdown viral transmission, the CDDEP experts have come up with an analysis of high-risk groups based on several factors, broken down by districts.
The data came from the National Family Health Survey of India 2015-16 (NFHS-4), which covered over 600,000 households and almost 2.9 million people over the full range of states and union territories in India. It provides details of socioeconomic and demographic characteristics, as well as of health indicators and family planning measures.
The researchers in the current study focused on the almost 700,000 women and over 110,000 men aged roughly 15-50 years, for whom biomarkers of anemia, high blood pressure, and diabetes were measured. The results were extrapolated to the older age groups mentioned below, to obtain the ‘high health risk’ indicator.
The analysts broke up the population into four groups:
- 70-79 years
- 80 years and over
- Those with diabetes or high-risk for diabetes (abnormal glucose tolerance, blood sugar over 140 mg/dL)
- Those with high blood pressure (over 160/100 mm Hg, singly or combined measurements)
High socioeconomic/demographic risk
In addition to these details, the researchers examined the number of health centers run by the government and by private providers at all levels, along with the proportion of patients who chose private hospitals over public facilities. Finally, they extracted the district-wise population.
They also attempted to characterize the wealth of the population, using social and material indicators. These include the possession of a bicycle, car, television, or radio, among other things, belonging to a scheduled caste or scheduled tribe (typically backward communities in most socioeconomic areas), and the type of housing construction, presence of toilets, power and drinking water at the household level.
The population served per health center at each level was also included. The district-wise data came from the NFHS-4, but the district reassignment led the researchers to match this data with the new districts mapped under the National Rural Health Statistics of India 2017 (NHRS 2017).
Urban districts were left out as the NHRS did not cover them. They created a composite index from these various parameters to represent the risk presented by various socioeconomic and healthcare access factors working together at the district level. The health risk was represented by the morbidity statistics mentioned above.
The government of India has designated 170 districts as hotspots of COVID-19 (April 15, 2020). These account for more than 8 of every 10 COVID-19 cases either in India or in their respective states, or are experiencing high rates of infection.
What are the study findings?
The current risk assessment model identifies districts in southern, northern, and western Indian states as being at the highest health risk. These include Tamil Nadu, Kerala, Punjab, and Maharashtra.
The 170 hotspots correlate well with the districts identified to be at high risk. The reasons for the higher risk in these districts include the higher percentage of older people and chronic medical conditions like diabetes and hypertension.
Secondly, the highest socioeconomic and healthcare access risk levels are in the three states already identified as BIMARU (“sick”), namely, Bihar, Madhya Pradesh, and Uttar Pradesh.
These populations are more impoverished, more rural, with a higher proportion of scheduled caste and scheduled tribe groups, and live at a lower standard than is the average for the rest of India. They also have lower than average access to public health facilities.
The paradox is that these people are less likely to contract the illness but more likely by far to suffer severe consequences because of the widespread poverty and poor availability of healthcare.
Offering a predictive model
The researchers emphasize that policy changes based on these findings should carefully take into account potential risk factors not included in the current study. The study does set up a predictive model for potential high-risk areas of viral transmission, which may help to mitigate the impact by preventive measures.
medRxiv publishes preliminary scientific reports that are not peer-reviewed and, therefore, not be regarded as conclusive, guide clinical practice/health-related behavior, or treated as established information.