Monkeypox continues to spread, and the first infection is now also being diagnosed in Germany. Is this a cause for concern, is the world facing a new pandemic? Scientists advise contact tracing and vigilance, but so far see no cause for concern.

Monkeypox is appearing outside of Africa for the first time. After several cases appeared in Great Britain last week, more and more countries are also reporting infections. They include Portugal, Spain, Italy, Sweden, Belgium, the USA, Canada and Australia. The first monkeypox infection has now also been registered in Germany. In the most recent Epidemiological Bulletin, the RKI warns of the pathogen and calls for suspected cases to be reported immediately.

How bad can it get? Has the virus become more dangerous for humans, are there drugs against it and is there even a threat of a new pandemic? Three scientists have given the Science Media Center (SMC) their assessment.

“We have not had any major outbreaks of monkeypox in Europe so the current development is unusual,” said Charlotte Hammer, College Position Fellow in Emerging Infectious Diseases at Downing College Cambridge. “Previously, cases of monkeypox in Europe were usually very sporadic and associated with travelers returning from Nigeria, for example.”

Little is currently known about monkeypox because the research is underfunded and underrepresented, she says. “Currently, about 1,500 cases are known, which means that our knowledge is only based on a few cases.”

“We urgently need good epidemiological data to understand whether and how the cases are related,” says Hammer. “Sequencing the genomes of the monkeypox viruses would also be important, because then we could see whether there were any indications of a change in the pathogen, and which ones for example, suggest better portability. Sequence data also help to identify chains of infection and to get clues to the origin.

She thinks it makes sense to make it compulsory to report monkeypox. “An important point is contact tracing, which is currently also being carried out intensively in the affected countries and is a core function of the healthcare system.” Hammer expects further cases, “if the transmission paths are via close physical contact, as previously assumed, a major outbreak is rather unlikely.”

Fabian Leendertz already recognizes an epidemic, but it is very unlikely that it will last long. “The cases of contact tracing can be well isolated and there are also drugs and effective vaccines that can be used if necessary,” says the founding director of the Helmholtz Institute for One Health (HIOH), Greifswald, and head of the project group “Epidemiology of Highly Pathogenic Microorganisms”. at the Berlin RKI.

The disease is also easy to diagnose, since there are usually quite typical skin changes. “The various PCR systems are also well established; the sequencing of the entire genome is unproblematic and serological methods are also available.”

Gerd Sutter from the Institute for Infectious Medicine and Zoonoses, Ludwig-Maximilians-Universität Munich (LMU), also estimates the risk of a major monkeypox epidemic in Germany to be low. Primary infections are zoonotic in origin. This means that they usually take place through direct contact with wild animals, for example when hunting and preparing venison.

Despite its name, the original animal reservoir of the pathogen cannot be found in monkeys. They are “also victims like ourselves,” says Fabian Leendertz. The main suspects are African rodents. Among other things, there were reports that the virus had been found in squirrels.

The cases of monkeypox currently observed in Europe are most likely infections that were originally brought in from Nigeria. “Human-to-human transmission is possible and usually requires direct contact with infected people,” says Sutter. “Transmission through aerosols is experimentally possible, but plays at most a subordinate role in natural infection.”

Transmissions of monkeypox are therefore “relatively inefficient compared to other infections such as influenza or Covid-19 and, in connection with adequate measures for diagnosis and contact determination, usually only lead to the formation of short chains of infection.”

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