Classification recommendations of the ZKBS: The influenza D virus

In a statement from April 2020, the Central Commission for Biological Safety (ZKBS) addressed the evaluation of the influenza D virus (FLUDV). To date, antibodies against the virus have been detected primarily in farm animals such as cattle, pigs, goats, sheep, horses, and dromedaries. It is assumed that cattle are the natural reservoir of the virus, as up to 80 percent of tested cattle were seropositive. Furthermore, antibodies against the virus have been detected in animals in Europe, North America, Africa, and Asia, thus FLUDV is widespread worldwide. The influenza D virus is primarily associated with the sometimes fatal enzootic bronchopneumonia (bovine influenza) in cattle. However, recent studies on experimentally infected calves show rather mild symptoms. It is therefore suspected that bovine influenza is not caused by FLUDV infections, but that the virus merely exacerbates the course of a disease caused by bacteria. Infections of other host animals are asymptomatic. Antibodies to FLUDV have also been detected in humans. Approximately 10 percent of the general population is seropositive. This rate sometimes rises significantly, particularly after an outbreak of infection in cattle. Furthermore, a seroprevalence of over 90 percent is reached, particularly among workers who handle cattle on a daily basis. However, symptomatic disease in humans is not known. The ZKBS recommends classifying the influenza D virus in risk group 2 for genetic engineering work, citing its broad host range, low animal pathogenicity, and previously unknown disease in humans.

We have sent you the complete statement from the ZKBS here linked.