A human lung, preserved in a jar for more than 100 years, helped scientists trace the history of measles.
According to the website Live Science, the lung in question was kept at the Museum of Medical History in Berlin, Germany, and belonged to a two-year-old child who died with measles in 1912.
A team of scientists at the Robert Koch Institute decided to take samples of the virus from the lung tissue and used the genetic material – the oldest genome of measles already sequenced – to learn more about the origins of this pathogen.
In the scientific study, published last week in the journal Science, researchers estimate that measles could have diverged from its closest known relative, the virus Rinderpest, in 528 B.C.
In statements to the same website, Sébastien Calvignac-Spencer, a virologist and one of the authors of the research, says that this new estimate suggests that the virus may be “more than a thousand years older than any previous estimate”.
Previous studies have predicted that measles and Rinderpest, which caused rinderpest, separated from their most recent common ancestor between the 11th and 12th centuries. However, the Persian physician Muhammad ibn Zakariya al-Razi also wrote a clinical description of measles in the 10th century.
The authors of this new scientific study point out that, before they found the sample aged 108, the oldest measles genome ever sequenced was dated 1954.
Based on when rinderpest and measles diverged, the “first possible date for the establishment of measles in human populations” occurred around the 6th century BC, although the exact date on which the virus first infected people, remain unknown.
The study authors noted that, about 2000 and 2500 years ago, humans began to build large enough villages to maintain a measles outbreak, offering the virus the opportunity to settle.
Measles tends to disappear in communities of less than 250,000 individuals, as residents quickly become immune or die of the disease, so that “small human populations could only serve as dead-end hosts,” they wrote.