Until recently, the staff of the poliovirus eradication campaign call centre in Islamabad would have received around 4,000 daily calls at the height of a vaccination push. The phones now ring as many as 70,000 times a day as staff instead hand out advice and information about Covid-19.

Likewise a nationwide surveillance network of doctors that once sought telltale signs of childhood polio paralysis now searches for suspicious coughs and fevers that could signal coronavirus infection.

Pakistan's internationally funded polio eradication programme has swung behind the country's efforts to tackle the pandemic.

Earlier this month, the Global Polio Eradication Initiative (GPEI) announced it would halt vaccination operations to stop door-to-door teams spreading the new illness, and instead dedicate staff and resources to tackling the pandemic.

The programme has for years received huge international investment and interest. Despite struggling to finally stamp out poliovirus, it is considered one of the best organised and most accountable parts of Pakistan's health infrastructure.