SARS-CoV-2 outbreak in German meat processing plant: Transmissions took place over long distances in air-conditioned working areas

24 Jul 2020 | Source: Helmholtz Centre for Infection Research (HZI)

Transmission via aerosols occurred over more than eight meters – housing conditions of workers of secondary importance

In a joint study of the Helmholtz Centre for Infection Research (HZI), the University Medical Center Hamburg-Eppendorf (UKE), and the Heinrich-Pette-Institute, Leibniz Institute for Experimental Virology (HPI), the origins of the first SARS-CoV-2 outbreak in May 2020 at Tönnies in Rheda-Wiedenbrück, Germany's largest meat processing complex, were investigated. The study results have now been published on the preprint platform SSRN. A publication in a peer-reviewed journal will follow.

The results reconstruct the initial transmission events in May 2020: Originating from a single employee, the virus was transmitted to several other workers within a radius of more than eight meters. The main transmission took place in the deboning area for beef quarters, where air is circulated and cooled to ten degrees Celsius. In contrast, the housing conditions of the workers did not play a significant role during the investigated phase of the outbreak.

In addition, an analysis of the virus sequences shows that all SARS-CoV-2 infected persons from the May 2020 infection cluster share a unique and novel set of eight mutations, which has not been reported so far.

"Our results indicate that the conditions within the deboning work area of the meat processing plant - namely the low temperature, low fresh air supply and constant air circulation through the air-conditioning system in the hall, together with hard physical work - promoted the aerosol transmission of SARS-CoV-2 particles over greater distances,” says Prof Adam Grundhoff, co-author of the study and research group leader at the HPI. “It is very likely that these factors in general play a significant role in the globally occurring outbreaks in meat or fish processing plants. Under these conditions, a distance of 1.5 to 3 meters alone is obviously not sufficient to prevent transmission."

About the Heinrich Pette Institute, Leibniz-Institute for Experimental Virology

The Heinrich Pette Institute, Leibniz Institute for Experimental Virology (HPI) investigates the biology of human pathogenic viruses with the aim of unraveling the molecular mechanisms that control viral life cycles and virus induced pathogenesis. The institute applies basic experimental research to develop new approaches for contemporary treatments of viral infections such as AIDS, influenza and hepatitis but also of emerging viral diseases.

The HPI was established by the philanthropist Philipp F. Reemtsma and the neurologist Heinrich Pette in 1948. The institute is a non-profit, independent research foundation that is part of the Leibniz Association.

The HPI is a member of DZIF, the German Center for Infection Research.Further information you can find here


Thomas Günther, Manja Czech-Sioli, Daniela Indenbirken, Alexis Robitailles, Peter Tenhaken, Martin Exner, Matthias Ottinger, Nicole Fischer, Adam Grundhoff, Melanie M. Brinkmann. Investigation of a superspreading event preceding the largest meat processing plant-related SARS-Coronavirus 2 outbreak in Germany. SSRN, 2020.