25 Health researchers, conservationists as well as other experts acknowledge primates are vulnerable, often fatally, to human respiratory diseases. In some African countries, viruses, some of which were tracked to humans and present only mild symptoms in them, have sickened and even killed apes.

The letter issued on wildlife urged countries with wild ape populations to consider halting wildlife tourism and minimizing field work, although an expert said that the sites would require additional financing to ensure critical personnel stay on the ground to avoid other threats to apes the major ones being poaching and deforestation.

A statement released by the International Union for the Conservation of Nature on March 15 “strongly” recommends that no human beings come within 10 metres, or around 33 feet of the great apes. It also advises that no person who has been infected or who has been in direct contact with the sick in the past 14 days should be allowed to visit the sites of great apes.

Dominic Travis, the co-author of the letter, said the letter also pointed towards zoos and sanctuaries that house great apes. Usually, staff at these facilities were trained to deal with disease outbreaks and risks, both at refuges in Africa and in well-funded Western zoos, where he said exhibits are also built to keep out human pathogens. But the pandemic is serious and he clarified that this is not to suggest that everybody has the money to cope with it.