According to a study, the origin of the international Mpox (formerly monkeypox) outbreak in 2022 dates back a long time.

Due to a striking change in the pattern and frequency of mutations, it can be assumed that the pathogen has been circulating among people since at least 2016, researchers report in the journal “Science”. According to the team, the way in which outbreaks are handled should be adjusted based on the observations. Global surveillance is necessary if the virus is to be eliminated in humans.

As the WHO recently reported, the number of registered Mpox cases in the European region has recently increased significantly again: 229 cases were observed there in September, an increase of 660 percent compared to August. At the peak of 2022, there were more than 8,000 registered cases per month in the region.

The WHO particularly highlighted Portugal, Spain, the United Kingdom, Germany and Ireland for this September. There is no official information that the cases and clusters reported in these countries are related to a known event. Otherwise, the WHO reports inconsistent developments depending on the region. In Germany, the outbreak is now taking place particularly in Berlin; the authorities there have reported around three dozen detections since the last week of July.

More than 91,000 Mpox infections in 115 countries

Mpox has long been considered a disease that is transmitted to humans through contact with rodents in West and Central Africa, the team writes in “Science.” Cases were treated as independent entries from the animal kingdom with subsequent limited transmission among humans. This remains true for one of the Mpox virus clades, writes the team led by Áine O’Toole from the University of Edinburgh. For clade IIb, however, most cases since 2016 are likely the result of human-to-human transmission. In many countries there are no options for identifying cases.

From May 2022 onwards, unexpectedly large numbers of people became infected with Mpox in many countries without known reservoirs in the animal world – including Germany. Numerous mutations were noticeable in samples from that time compared to older virus sequences. The study describes the multiple increased mutation rate as a result of the ongoing confrontation with the human immune system.

The most noticeable symptom of the disease are blisters and pustules on the skin. The World Health Organization (WHO) declared an international health emergency because of Mpox last year. This was ended again in May 2023 after the number of cases fell significantly. In total, the WHO recorded more than 91,000 Mpox infections in 115 countries and almost 160 deaths from January 2022 to the end of September 2023.

Mpox viruses are transmitted through close physical contact. According to the WHO, men who have sex with men were predominantly affected by the outbreak. According to a database from the Robert Koch Institute, a total of almost 3,740 cases have been reported in this country, 3,671 of which occurred in 2022.