Social distancing, isolation and strict personal hygiene helped Jews overcome a typhus epidemic in the Warsaw Ghetto during World War II. That’s the conclusion of a historical-science study published in the July 24 issue of Science Advances.

The authors, who made use of mathematical modeling alongside historical documents, argue that education, explanation and behavior are more important than reliance solely on government decisions in controlling epidemics. Prof. Lewi Stone, a biomathematician from Tel Aviv University, led a research team that included colleagues from Hong Kong, Amsterdam and Berlin.

The Warsaw Ghetto was established in 1940 and at its peak it held around 450,000 people, crammed into an area about the size of Manhattan’s Central Park. Starvation, overcrowding and terrible conditions made the ghetto ripe for the spread of bacterial infection that lead to an outbreak of typhus – less infectious, but more lethal than the coronavirus that causes COVID-19.

In January 1941, a major typhus epidemic broke out in the ghetto. According to the study, 120,000 prisoners in the ghetto were infected with the disease, and around 30,000 died as a direct result of the illness. Many others died from a combination of typhus and starvation.

While a steep rise in the number of infections was expected in the winter of 1941, in October the infection curve began to fall, in an unexpected and even “mysterious” manner, according to Stone.

Stone used mathematical modeling in an attempt to determine whether the epidemic burned out naturally or was due to the actions of the ghetto’s doctors and prisoners. He discovered that the key lay in education, public health measures and the cooperation of residents. “There were many experienced physicians and specialists in the Warsaw Ghetto,” says Stone. One of them, Ludwik Hirszfeld, was an eminent Polish-Jewish bacteriologist and Nobel Prize nominee.

The out-of-control rampant spread of typhus followed quickly on the heels of the horrific starvation phase. Typhus is a bacterium (Rickettsia prowazekii) spread by its vector, the human body louse (Pediculus humanus humanus). The latter multiply prolifically under conditions of poor hygiene, filth, overcrowding, and cold weather—exactly the conditions of the ghetto. Given its population density and overall conditions, little wonder that the ghetto was commonly referred to as an “incubator” of disease and “breeder of epidemics.” Ludwik Hirszfeld, the eminent bacteriologist and Nobel Prize nominee living in the ghetto, had no doubts: “In the case of WW2, typhus was created by the Germans, precipitated by lack of food, soap, and water, and then—when one concentrates 400,000 wretches in one district, takes everything away from them, and gives them nothing, then one creates typhus. In this war, typhus is the work of the Germans”.

Lice thrive in large numbers on their human hosts, feed daily on their blood, and have rapid spatial spread, which allowed them to infest the entire cramped ghetto. For those infected, typhus typically has a ~14-day incubation period and results in a high fever, headache, muscle pain, nausea, chills, and extensive body rashes. As the disease progresses, increasing weakness and delirium develop, and in some cases, loss of consciousness. Death can result within a few days for the worst cases. Accounts may be found of sufferers jumping through windows in agony to their death. When the human host dies, the vector simply moves to another victim.

Forest fire dynamics

The ghetto’s population numbers fluctuated but, at times, contained at least 450,000 people in an area of 3.4 km2. This density is some 5- to 10-fold higher than the densest city in the world. In January to March 1941, the Germans forced 66,000 displaced refugees into the ghetto, soon after it was sealed. Initially, new arrivals were quarantined for 14 days to prevent typhus spread, but the practice was soon abandoned. From this moment, the epidemic was unstoppable. “The first signs of disease appeared among the [refugees] … who were crowded like animals into the institutional buildings. So high was the death rate in these places that they were popularly known as death points. It was not long before the first sparks of disease spread like a forest fire throughout the entire ghetto”. Surprisingly, this quote from 1950 might be the very first verbal model of a disease outbreak couched in terms of what would decades later became the physicists’ famous “forest fire” epidemic paradigm.

Sudden curtailment of the typhus outbreak

As shown in Fig. 1, unusually, in late October 1941, just at the onset of winter, the typhus epidemic rapidly began to curtail and collapse. The epidemic’s “turnaround” was completely unexpected since typhus infection normally accelerates during winter. As Emanuel Ringelblum, the ghetto’s chronicler, wrote (November 1941): “The typhus epidemic has diminished somewhat—just in the winter, when it generally gets worse. The epidemic rate has fallen some 40 per cent. I heard this from the apothecaries, and the same thing from doctors and the hospital.” The same feature was also recently noticed in the thoroughly researched book of Miriam Offer. Here, we use a modeling approach to help understand the epidemic’s unexpected collapse. Namely, we ask, did the epidemic naturally burn out? Or were other factors responsible?

The transmission dynamics of typhus in Warsaw Ghetto was usually through contact or close proximity to an already infected individual, as this allowed lice to pass from one host to another in the densely crowded ghetto. Residents were terrified of accidental contact and practiced social distancing.

For his study, Stone pored over piles of documents in archives and libraries throughout the world, in search of contemporary descriptions of the measures that were taken to fight the epidemic in the ghetto. He found evidence of training sessions on hygiene and infectious diseases as well as lectures on these topics in the medical school that operated secretly in the ghetto.

Sadly, nearly everyone who avoided typhus in the Warsaw Ghetto thanks to these measures was eventually murdered in the Nazi death camps. The study cites Hans Frank, the head of the General Government (Occupied Poland) in Poland during the war, as having said in 1943 “that the genocidal murder of 3 million Jews in Poland ‘was unavoidable for reasons of public health.’” It also quotes Jost Walbaum, the chief health officer of the General Government, as saying in October 1941 that “The Jews are overwhelmingly the carriers and disseminators of typhus infection…. There are only two ways [to solve this]. We sentence the Jews in the ghetto to death by hunger or we shoot them.”

Header: Warsaw Ghetto: Possibly corpse of starvation victim in front of building at Leszno 43 street – Bundesarchiv, Bild 101I-134-0771A-39 / Zermin / CC-BY-SA 3.0

Source: Ofer Aderet – HAARETZ

Original study: SCIENCE ADVANCES