An ongoing measles epidemic in Pakistan is claiming hundreds of children’s lives, reports the BBC. Doctors say that this is the worst epidemic they’ve seen in 20 years, with more than 70 new patients arriving daily. Some parents unknowingly wait to bring their child to the hospital after it is too late for medical staff to provide much help, especially if advanced pneumonia or meningitis has set in.

Between January to April this year, Pakistan reports that 239 children have died, the BBC writes. But the epidemic kicked off well before the new year. Al Jazeera reports:

The latest figures from the World Health Organization (WHO) show the number of measles cases in Pakistan has increased from 4,000 in 2011 to 14,000 in 2012. Of those, 306 died last year – up from 64 deaths in 2011.

Lack of vaccines, experts believe, accounts for much of the epidemic’s intensity. According to Al Jazeera, worldwide vaccination campaigns resulted in a 74 percent drop in measles deaths between 2000 and 2010. Some areas of Pakistan hit the hardest have only a 58 percent vaccination rate, the BBC reports. Some families cite lack of time or means to get their children vaccinated, though massive measles vaccination campaigns have been underway in the country for several years. The BBC writes:

While doctors here say families need to take more responsibility for ensuring their children are vaccinated, they accept the official vaccination programmes have often been badly managed, leading to people missing out.

According to Al Jazeera, some families are also suspicious of vaccination programs.

The reason for their suspicion is that, in 2010, the CIA set up a phony vaccination drive against Hepatitis B to help track Osama bin Laden. A Pakistani doctor was recruited to carry out the work in poor villages. His goal was to gain entry to the compound where bin Laden was suspected of hiding and get DNA samples from those living there. The programme apparently failed. And the doctor is now serving 33 years for treason. Some groups say the vaccination programmes are used to sterilise Muslims, or cause them harm. The Taliban has repeatedly threatened health workers involved in vaccination work. And in recent weeks, a number of health workers have been shot dead. It is unclear who is behind the attacks.

Aid workers are undeterred, however. According to the BBC, 2.6 million children have received vaccines in Pakistan over the past few weeks, and in June another 11 million are due to arrive. Health workers hope this push will finally get the epidemic under control.

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