Pakistan has recorded a 70% drop in polio cases.

As at October, officials said that Pakistan had its highest number of cases for 15 years - which came to 200 cases across the country, mostly due to militant attacks. However, so far in 2015 there have been about 25 cases.

Most polio infections are in the north-western tribal region where militants have targeted health teams.

The militants accuse doctors of being spies and say the vaccinations are part of a Western plot to sterilise Muslims.

According to prime ministerial polio adviser Ayesha Raza, while it had taken time to eradicate militancy in North Waziristan, the rewards from doing so were "already visible in the polio programme"

In a chat with BBC, Raza said polio samples from high-incidence zones - which used to be positive for months on end - were now testing negative again.

She added that the Federally Administered Tribal Areas (Fata) had only reported seven cases so far this year while Karachi had reported none.

Officials say that in recent months there has also been a clear decline in the number of attacks on polio teams, and a number of men involved in such attacks have been arrested.

Meanwhile, in related news, Nigeria has reported no new cases this year, while Afghanistan has only reported one.