A fatal flesh-eating disease is making its rounds in conflict-ridden Syria, owing to the rotting corpses dumped on the streets and the lack of medical services.

Leishmaniasis, currently spreading in ISIS-controlled areas in the country, is mainly transferred by bugs feeding on the dead bodies on the streets.

A media report says that the first case of leishmaniasis, caused by fly-transmitted protozoan parasites, first came out in September 2013. From there, Syrian activists had rung the alarm on over 500 individuals suffering from the dreaded disease by mid-2014.

Dilqash Isa of the Kurdish Red Crescent, in a separate news report, decries ISIS' terrorist acts as the culprit behind the quick spread of the disease.

"[These] included the killing of innocent people and dumping their corpses in streets," he says.

According to a Kurdish fighter, the disease hails from embattled locations Tal Hamis, Hon and Qosa. They reportedly did not have knowledge about leishmaniasis in the early part of their four years out on the battlefield.

The World Health Organization warned that aid agencies are scrambling to provide enough medical supplies to over 13 million Syrians in urgent need of attention and help.

"Despite our best efforts, health needs are escalating, and more than four years of crisis is causing the Syrian health system to deteriorate," warns WHO in an official statement, echoing an increased number of trauma cases, mental health needs, reproductive issues and diseases in the country stricken by civil war.

WHO estimates that 310 million individuals are at risk of the infection in six countries reporting more than 90 percent cases of visceral leishmaniasis, the most severe disease form that can be deadly if left untreated.

Also known as kala-azar, visceral leishmaniasis affects vital body organs and is marked by irregular episodes of fever, weight loss, spleen and liver enlargement, and anemia.