For the first time in Pakistan's history all the previous month's environmental samples for polio have tested negative – a sign of progress in the campaign to eradicate the virus, according to an official.
New immunisation campaigns
A total of 40 samples were collected from 14 cities in mid-April under the supervision of the World Health Organisation and analysed at the National Health Institute, said Dr Rana Safdar, the head of the National Emergency Operation Centre. WHO officials could not immediately be reached for comment.
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Last year 22 percent of environmental samples tested positive, and 9 percent tested positive in the first quarter of 2016.
Safdar said the negative samples represent a "significant achievement" but that complete eradication would require more "consistent efforts". He said new immunisation campaigns have been planned in vulnerable areas starting in July, after the end of the fasting month of Ramadan.
Past immunisation campaigns have been met with resistance by Islamic extremists, who have spread conspiracy theories that the vaccines are part of a plot to sterilise children or gather intelligence for western nations.
Read: Pakistani parents arrested for refusing polio vaccination
Islamic militants have attacked vaccination centres and health workers taking part in the campaigns.
Eleven cases reported
But Safdar said outreach programmes supported by religious scholars have helped to combat the propaganda, bringing the refusal rate down from 1.5 percent to 0.05 percent over the last two years.
Pakistan and Afghanistan are among the only countries in the world where polio is endemic. Eleven polio cases have been reported so far this year in Pakistan, compared to 54 last year. The highly infectious virus mainly affects small children, and can cause paralysis.
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