Bee colony tested positive on American foulbrood

Published on
June 1, 2021

The National Reference Laboratory (NRL) for bee diseases has identified an outbreak of the infectious bee disease American foulbrood by culturing samples collected from a beekeeper in the province of Groningen. The bee colony is being exterminated. Outbreaks of American foulbrood are rare in the Netherlands.

American foulbrood (AFB) is a bacterial brood disease affecting honey bees and is one of the four notifiable bee diseases. Beekeepers with a suspected case of the disease are required to report it through the animal disease notification portal. AFB only affects the larvae in the beehive. Adult bees are not infected by the spores of the bacteria. When infected with the disease, the honeycomb will have unevenly distributed and sealed brood cells with some concave cell lids. The cells will be filled with off-white or yellow-brown mucus threads and will have a glue-like odour.

Combating American foulbrood

Outbreaks are dealt with by beekeepers themselves, with the help of bee health coordinators, overseen by the Netherlands Food and Consumer Product Safety Authority (NVWA). To support beekeepers in combating the disease, the Ministry of Agriculture, Health and Food Quality has banned the movement of bee colonies within three kilometres of the site of the infection. This ban will be in place for at least 30 days.

National Reference Laboratory for bee diseases

The National Reference Laboratory for bee diseases is a statutory research task carried out jointly by bee experts at Wageningen Plant Research (WPR, bees@wur) and veterinary researchers at Wageningen Bioveterinary Research (WBVR). Outbreaks of American foulbrood occur less than once a year in the Netherlands. The disease is caused by the Paenibacillus larvae bacteria, which produces large quantities of spores in an outbreak. These spores can be distributed in various ways, including through the exchange of infected hive materials and through bee escapes and robbing. The spores are also very persistent and can remain latent in a bee colony for a long time. There have been 73 outbreaks of AFB since 1990.