As India surpassed the two lakhmark of daily cases in mid April 2021, a political brawl broke out between the union government and some states over an alleged shortage of vaccines. This is adding to a series of setbacks in India’s trystwithCovid-19. Health Ministers of several states have accused the union government of limiting supplies to their states. Additionally, states are struggling with an acute shortage of oxygen when there has been a rise in both the caseload and the fatality rates.

Given the insufficient health supplies to treat the everincreasing cases, it is imperative to have the population vaccinated.The government launched the Covid-19 immunization program, starting with frontline workers and gradually moving down the infection risk hierarchy. Close to 113 million people have received the first dose at the time of writing, and 19 million people have completed both doses.

The union government has decided toopen the vaccine programme for all adults starting from 1 May. The government has a target to immunize 250 million people by the end of July 2021. Thus, it is important to have a systematic process forvaccine allocation across the states. There have been announcements promoting immunization like Tika Utsavand others; however, there is no transparency about the distribution of vaccines across the country. The statewide data of vaccines distributed so far indicatethat vaccines were initially distributed proportionate to active cases, and later on a need-based model is being followed.

The states are now being provided with vaccines based upon their utilization in the previous days. Here we have discussed a matrix formula for vaccine allocation that holds a robust and scientific nature. The need and allocation of vaccines across the states dependon their population size, exposure, and vulnerability to the pandemic. Here, we have used a set of 6 indicators covering the three dimensions: demography, severity of current wave,and vulnerability towards infection.

All three dimensions are given equal weights in order to compute an aggregatescore that is nothing but a proposed share of vaccines to be provided to a state or a union territory. Demographic dimension is measured by percentage distribution of India’s population age 45 or above across the states and UTs. In the absence of census data, figures for the year 2021 are derived from thelatest Population Projections for India and States report and the fourth round of the National Family Health Survey.

The severity aspect is covered by the percentage distribution of total confirmed cases and deaths attributed to Covid-19 in the last two weeks. The same is collated from covid19india.org, an independent aggregator of Covid-19 related data, and the official website of the Ministry of Health and Family Welfare. State of vulnerability is estmatedon the basis of three indicators- percentage share of population age 45 and above with multimorbid conditions, proportion rural population not covered by community health centers, and percentage distribution of India’s urban population across the states and UTs.

A wide range of literature suggests that the increased share of urban dwellers and older adults with multimorbidity conditions as well as lack of access to quality healthcare increases the vulnerability of infections and deaths attributed to SARSCoV-2. Data for urban population and multimorbidity are obtained from Population Projections for India and Longitudinal Ageing in India Study reports.

The distribution of rural population ideally uncovered by CHCs has been calculated based on the standards prescribed by National Health Mission (NHM) by obtaining the state-wise number of CHCs from Rural Health Statistics report 2019-20 and rural population total from Population Projections for India and States report. As per NHM norms,one CHC is supposed to serve 120,000 populations in plain areasand 80,000 populations in hilly/tribal areas.

For states with a significant combination of plain and hilly/tribal areas, we have considered the threshold of 100,000 populations to be covered by a CHC. Rural population exceeding the productof number of CHCs and standard population covered by a CHC is defined as rural population not covered by CHCs. According to this proposed formula, the top five states that seem to be in dire need of vaccines are Maharashtra, Uttar Pradesh, Karnataka, Bihar, and West Bengal.

As an aggregate, these five states should be receiving 50 per cebt of the total vaccines given the high vulnerability in these states; however, the existing figures of first vaccine dose indicate that they are receiving only 37 per cent of the total share. There is an inequality in distribution and the rising fatality each passing day leaves no room for error. Moving on to individual states, the states of Delhi and Maharashtra are getting only 56 and 57 per cent of the proposed share, indicative of a massive deficit in vaccination coverage.

The states of Tamil Nadu, Uttar Pradesh, Punjab, and Bihar are entitled to about 70 per cent of the proposed share, standing at a deficit of 30 per cent vaccine coverage. On the other hand, Karnataka, Chhattisgarh, Jharkhand, Andhra Pradesh, Telangana, and West Bengal even out with the proposed formula and are receiving the ideal vaccine coverage.

The states of Madhya Pradesh, Meghalaya, Nagaland, Haryana, Kerala, Uttarakhand, Jammu & Kashmir, and Gujarat are receiving a relatively higher share of vaccination. In contrast, larger states such as Odisha and Rajasthan and smaller states like Himachal Pradesh, Mizoram, Arunachal Pradesh, Tripura, and Sikkim are receiving much more doses, 200 per cent or more of the proposed share.

The current formula of vaccine distribution among states is not clear; it seems to be determined based on vaccines utilized on a preceding days.It is crucial to adopt a scientific calculation for vaccine allocation, transparent and inclusive of various severities around the disease. To establish a logic, we have computed an integrated formula that acknowledges six predictors of disease severity and assigned equal weights to each of them.

The distribution within states can further be computed using similar criteria assessing the spread and severity in various cities to administer the vaccines accordingly. It may be noted that the proposed formula here allocates vaccines based on the severity of the pandemic in the last two weeks in a particular state. It is suggested to update these valuesevery week and change the allocation of vaccines accordingly. Also, considering the allowances for younger age groups, the demographic factor can be modified accordingly to get respective values.

Lastly, the vaccines must be utilized to their maximum capacity without any wastage. A positive behavior towards vaccine was seen during the phase of increased risks and fear in Italy; however, residents developed hesitancy and doubts about vaccine over time. Hence, given the current surge phase in India, it is essential to have a wellequipped system covering the maximum population with the doses. The government needs to devise a more strategic immunization program that encourages more people, especially the vulnerable ones, and results in minimum wastage.

(The writers are with the International Institute of Population Sciences, Mumbai)