Chaos in war-torn Yemen is obscuring the "horrific" extent of the coronavirus epidemic in the country, leaving scientists to make educated guesses at the number of deaths caused by the disease based on burials. The estimates are grim: the crippled city of Aden alone has likely seen a five-fold increase in deaths since COVID-19 arrived.

The international aid group Doctors Without Borders has issued a stark warning about the severity of the health crisis in the crowded southern port city. The group, known by its French acronym MSF, supports 17 hospitals across the country Yemen, including two COVID-19 treatment centers in Sanaa and Aden.

"The number of deaths occurring in the COVID-19 treatment center that MSF runs in Aden, Yemen, speaks to a wider catastrophe unfolding in the city," the group said in a statement, calling on the United Nations and donor countries "to do more urgently to help the response."

"The situation in Aden is bad, for lack of other words. We have no beds anymore," Claire Ha-Duong, head of the MSF mission in Yemen, told CBS News. "The problem is that in private hospitals [COVID-19] patients are refused and there is very little capacity for other patients in other hospitals."

She said MSF initially had to refuse one patient admission to a hospital because there was literally no space. "He stayed at the door for hours until, it's horrible to say, one patient died and then one bed was free."