Ear infection plagued people in Israel 15,000 years ago, study finds

Illustration of a longitudinal cross section of the ear and the region of interest where signs for ear infection were examined (a "healthy" ear) (photo credit: ARIEL POKHOJAEV/DEPARTMENT OF ANATOMY&ANTHROPOLOGY/SACKLER FACULTY OF MEDICINE/TEL AVIV UNIVERSITY)
Illustration of a longitudinal cross section of the ear and the region of interest where signs for ear infection were examined (a "healthy" ear)
(photo credit: ARIEL POKHOJAEV/DEPARTMENT OF ANATOMY&ANTHROPOLOGY/SACKLER FACULTY OF MEDICINE/TEL AVIV UNIVERSITY)
Once an extremely dangerous illness, ear infections have been plaguing humanity for at least fifteen millennia: A group of Tel Aviv University researchers found that the inhabitants of ancient Israel suffered from it already 15,000 years ago.
Ear infections can be studied in a precise way because they leave very specific signs in the middle ear which can only be caused by it, Dr. Hila May of the Department of Anatomy and Anthropology at TAU’s Sackler Faculty of Medicine and the Dan David Center for Human Evolution and Biohistory Research explained to The Jerusalem Post.
“However, in the past in order to examine the middle ear in a skull, the skull had to be opened and therefore damaged. New technologies that we have in our labs have allowed us to overcome the challenge,” May, who is the lead author of a study recently published in The International Journal of Osteoarchaeology, further pointed out. Other authors of the paper include Katarina Floreanova, Efrat Gilat and Ilan Koren.
The scholars employed a videoscope featuring a flexible tube equipped with a micro-camera at the end to explore the ear canal and the middle ear. Moreover, the skull remains were scanned with a high-resolution micro-CT.
The group examined over 220 skulls from a local population dating from six different periods between 15,000 to 2,000 years ago.
They found out that the frequency of the illness declined as the population’s lifestyle transitioned from hunter-gathering to sedentary: among the hunter-gathers, the morbidity was about 70%, which declined to 60% among early farmers. However, a new peak was registered around 6,000 years ago, increasing the percentage of specimens presenting signs of ear infections to 80%. Then once more the infection rate decreased and it stabilized at around 50%, the same where it stands today.
If the more stable life initially allowed those ancient populations to be less affected by infections, some factors, including a decrease in temperatures and an increase in rainfall, but also the poor living conditions, with men and animals crammed together in small spaces, probably caused the illness to increase. When the conditions improved again, the morbidity went down.
All the skulls came from excavations conducted in Israel.
“Studying samples from Israel presented the advantage that all those ancient individuals lived under similar conditions since we are speaking about a small region, even though the climate conditions changed over the time with the Chalcolithic period presenting a more rigid weather, which might have been part of the reason for a higher morbidity at that time,” the researcher said.
May pointed out that all the examined skulls were from adults, but that the marks left by the infection in the middle ear would have not disappeared even if the individual had developed the illness as a young child, as it is common to this day, although thanks to the discovery of antibiotics, the consequences are way less severe.
“Learning about diseases’ history and how they behaved in the past helps us understand how diseases develop, appear or disappear,” she concluded. “An ear infection is something that we have suffered from since forever because of our anatomy. Understanding how ancient populations lived with it and what factors were the most influential is relevant to this day.”