The region is home to some 4.5 million unimmunized or partially immunized children and most of them, or 97 per cent, live in India, Pakistan, and Afghanistan, the UN body said in a statement.
"With lockdowns in place as a part of the novel coronavirus response, routine immunizations have been severely disrupted, and parents are increasingly reluctant to take their children to health centres for routine jabs," Efe news quoted the statement as saying.
The agency warned that sporadic outbreaks of vaccine-preventable diseases, including measles and diphtheria, have been detected in parts of Bangladesh, Pakistan, and Nepal.
The region is also home to two of the last polio-endemic countries in the world, Afghanistan and Pakistan.
"Vaccine stocks are running dangerously low in some countries of the region as supply chains have been disrupted with travel bans and canceled flights. The manufacturing of the vaccines has also been disrupted, creating additional shortages," said
Many of the health facilities throughout the region for vaccination of millions of children were closed and outreach sessions suspended, adding to the challenge.
"As long as frontline health workers take the appropriate precautions, particularly washing their hands, there is no reason not to vaccinate," Rutter emphasized.
National mass vaccination campaigns have also been postponed across the region.
Bangladesh and Nepal have postponed their national measles and rubella campaigns, while Pakistan and Afghanistan have suspended their polio campaigns.
"We are very concerned about the impact of not getting children vaccinated," said Jean Gough, Director of Unicef ROSA.
"Many of these children are already vulnerable. While the COVID-19 virus does not appear to make many children seriously ill, the health of hundreds of thousands of children could be impacted by this disruption of regular immunization services. This is a very serious threat. Early action is key."
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