A massive wave of coronavirus infections is blasting through the world's largest prison population in the United States even as officials begin opening up their economies, saying the disease has plateaued.

According to an AFP report, one prison in Marion, Ohio has become the most intensely infected institution across the country, with more than 80 per cent of its nearly 2,500 inmates, and 175 staff on top of that, testing positive for Covid-19.

Coronavirus deaths are on the increase in jails and penitentiaries across the country, with officials having few options — they are unable to force adequate distancing in crowded cells and facing shortages of medical personnel and personal protective gear everywhere.