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Analysis of five rounds of the National Family Health Survey (1993-2021) reveals that the prevalence of unvaccinated children increased in the north-eastern states and in Uttar Pradesh, Bihar and Maharashtra Maharasthra between the two most recent surveys1.

Children who missed a single dose of vaccine against diphtheria, tetanus or pertussis in the first year of life were referred to as zero-dose or unvaccinated. For most states, the relative reduction in zero-dose children was higher in rural than urban areas, says an international research team.

Scientists, led by S. V. Subramanian and Sunil Rajpal, analysed the vaccination status of 125,619 children aged 12 to 23 months from the national survey data between 1992 and 2021.

The team, which included researchers at Flame University in Pune, India, and Harvard University in the United States, found that nearly 1.37 million children remained unvaccinated in 2021. In absolute terms, this is a decrease from 26.8% to 6.6%.

In 1993, the occurrence of zero-dose children was highest in Jharkhand, Bihar, Rajasthan, Uttar Pradesh and all the north-eastern states.

Between 2016 and 2021, the prevalence of unvaccinated children increased in 10 states, including several high-performing states and union territories, such as Punjab, Telangana, Kerala, Puducherry, Chandigarh and Sikkim. In 2021, 53% of the zero-dose children lived in Uttar Pradesh, Bihar, and Maharashtra.

The COVID-19 pandemic, geographical barriers and lack of awareness disrupted vaccination drives in Meghalaya, Nagaland, Mizoram and Arunachal Pradesh, increasing the number of unvaccinated children in these states.

The researchers say that awareness camps and programmes such as Intensified Mission Indradhanush 4.0, a national initiative to improve immunisation, can protect children against vaccine-preventable diseases.