Mpox/Monkeypox - What the HZI experts say

Since mid-May 2022, several countries where mpox/monkeypox is not endemic have reported an accumulation of infections with the monkeypox virus. Cases have also been diagnosed in Germany, as of May 2023 around 3700 infections were recorded. Researchers at the Helmholtz Centre for Infection Research (HZI) are contributing their expertise to assessing the current situation and informing the public.

Monkeypox virus (MPXV) is related to the eradicated smallpox virus. Despite the name, monkeys are not the natural reservoir of the virus. Instead, rodents are probably the reservoir from which monkeys can also contract the virus. It is currently unknown via which animals the virus has jumped to humans in the current cases. On 23 July 2022, the World Health Organisation (WHO) declared the outbreak a Public Health Emergency of International Concern (PHEIC). The global health emergency was ended in May 2023.

Prof Fabian Leendertz, founding director of the Helmholtz Institute for One Health (HIOH) in Greifswald and head of the department "Ecology and Emergence of Zoonoses", studies the interface between animal health, the environment and human health. The HIOH is a site of the HZI, which is being established together with the University of Greifswald, the Greifswald University Medicine and the Friedrich-Loeffler-Institute, Federal Research Institute for Animal Health (FLI) as local founding partners. He assesses the current situation as follows:

"Unfortunately, the opportunity to contain this pathogen in time was missed. This shows that we have to take infectious diseases seriously worldwide and cannot assume that monkeypox in Africa, for example, has nothing to do with us."

Prof Fabian Leendertz, Founding Director of the HIOH

Mpox/Monkeypox is another health problem that puts an additional burden on health systems, costs a lot of money for research and countermeasures and will remain among us humans for a long time to come, says the zoonoses expert. In the past, he has already published studies on the occurrence of the mpox/monkeypox virus in chimpanzees (publication in Nature Microbiology) and sooty mangabey (publication in Emerging Infectious Diseases) in Cote d'Ivoire.

In another interview with Tagesschau, he comments on the transmission of the virus and symptoms: "The virus causes clear symptoms and with classical contact tracing, chains of infection can be traced to contain the outbreak."

The relationship of the monkeypox virus to the smallpox virus also has consequences for the vaccine. There is cross-reactivity between the viruses - the smallpox vaccine also protects well against monkeypox infection, although not 100%.

"Smallpox vaccination can provide protection against monkeypox infection for many decades or lead to milder clinical symptoms."

Prof. Luka Cicin-Sain, Head of the Department "Viral Immunology"

This is what Prof Luka Cicin-Sain, Head of the Department “Viral Immunology” at HZI, says about people who were vaccinated against smallpox in childhood. In the FRG, compulsory smallpox vaccination was lifted in 1976, in the GDR only in 1982. Most young people are no longer vaccinated against smallpox and therefore have no protection. Despite its name, the chickenpox virus does not belong to the smallpox family, but to the herpes viruses. A chickenpox infection or vaccination therefore also offers no protection against mpox/monkeypox.

Mpox/Monkeypox outbreak investigation in Nigeria 2017 - 2019

In 2017, a mpox/monkeypox outbreak was observed in several regions of Nigeria. The Department “Epidemiology” at HZI, headed by Prof Gérard Krause, then further developed the digital tool for disease control SORMAS (Surveillance, Outbreak Response Management and Analysis System) within a very short time and provided a mpox/monkeypox module. SORMAS helps to collect data on transmission routes and the geographical distribution of infection cases.

A research team led by Prof Gérard Krause was involved in the investigation of a mpox/monkeypox outbreak in Nigeria from 2017 to 2019 and also used the SORMAS digital system to contain the outbreak. The scientists published their findings in the journals The Lancet Infectious Diseasesand Emerging Infectious Diseases.

In November 2022, the WHO recommended the name mpox as a synonym for monkeypox. This article has been updated to reflect that decision.