Pakistani authorities and United Nations agencies said Thursday they will immunise 63 million children against measles in the biggest such campaign in history.
The virulent disease is one of the deadliest threats to young people in Pakistan, claiming the lives of 58 children a day, but vaccination coverage here is currently only 69 percent.
"It is the largest immunization campaign in the world. I think it will show a lot of results," health minister Nasir Khan told a news conference in Islamabad.
The campaign targeting all children aged up to 13 years is due to start on Monday in southwestern Baluchistan province. It will cover the whole country by March 2008, officials said.
It involves the Pakistani government, the UN Children's Fund (UNICEF) and the UN World Health Organisation.
Volunteers will travel to schools and Islamic seminaries known as madrassas to give children the measles jabs, while government-run clinics will be also be used as vaccination centres.
Medics will make special plans to reach isolated mountain and desert communities.
"This is the largest campaign in the history of Pakistan and probably the largest globally. It is very different from the routine measles injection campaigns," UNICEF programme communication officer Melissa Corkum told AFP.
"We will have to achieve high coverage, ensure high social mobilisation and safe vaccination to significantly reduce child mortality and morbidity," she added.
A pilot campaign in Pakistan in March reached 95 percent of targeted children, she said.
The relatively low vaccination levels in Pakistan mean it has regular outbreaks of measles, which kills up to 10 percent of its victims, causes male sterility and weakens children's immunity.
Around one million Pakistani children catch measles every year and nearly 21,000 die from it.
The previous largest anti-measles campaign took place last year in Bangladesh, where 33.5 million children were targeted, UNICEF said.
The United Nations said in January that measles deaths have fallen by 60 percent worldwide since 1999, from 873,000 to 345,000, largely due to a decline in Africa.
Measles was the world's single most lethal infectious disease before an effective vaccine emerged in 1963.