Between 1940 and 1943, over 90,000 Jews died in the Warsaw Ghetto of starvation and disease. But that number could have been much higher if not for the efforts of doctors and ghetto officials who managed to stop a typhus epidemic in its tracks, a new study suggests.

An international group of researchers wanted to know why a deadly typhus outbreak in the ghetto fizzled in 1941. They recently published their research in Science Advances.

The Nazis scapegoated Jews as supposed disease vectors to justify placing them in the ghetto in 1940 and 1941. Then, they increased the chances that Jews would contract and spread disease to one another. Over 400,000 people were packed into just 1.3 square miles and given starvation rations — only 200 calories per person, per day.

Sure enough, typhus, which is transmitted by lice bites, spread through the ghetto with a pace compared to that of a forest fire by contemporary observers.

But instead of accelerating with the onset of winter, cases suddenly dropped 40 percent.

Why? To simulate the epidemic, the researchers used a model that assumes people are either susceptible, exposed to, infected with or recovering from a disease being transmitted in a community, then assumed a 25 percent reporting rate consistent with historical reports. Their simulation matched data recorded by epidemiologists and medical specialists within the ghetto.

If nothing had intervened, researchers estimate the epidemic would have ballooned to about 196,000 cases peaking in January 1942. Instead, 80,000 to 110,000 residents were infected and the epidemic peaked in October 1941.

Behavioral response must have driven the decrease, researchers conclude. Public health education campaigns, social distancing, a community feeding program that distributed slightly higher amounts of food and a push to help people identify, monitor and quell lice are possible reasons the epidemic stalled.

“The Warsaw Ghetto residents were completely unaware of what had been achieved,” the researchers write. Tragically, an even worse fate was ahead for most of those who survived. Nearly all of the Warsaw Ghetto’s residents were deported to concentration, forced labor and extermination camps, and about 7,000 were killed during an armed uprising in 1943 during the ghetto’s liquidation.