HILO — A long-simmering threat to Hawaii Island’s honeybees has resurfaced.
American foulbrood, a disease caused by bacteria that infects bee larvae, was discovered in a hive in Volcano last week. A case was reported on Maui in March. Last year, there were two cases on Oahu and one reported in Waimea.
Found around the world (it originated in Europe but was first scientifically identified in the United States), American foulbrood is considered the most destructive honeybee brood disease. Onset is typically slow as bacteria infect and kill larvae, but a colony also can be weakened quickly.
There is no cure for the disease and the spores that eventually become bacteria can live up to 80 years.
“You wouldn’t see it outside the hive,” said Lauren Rusert, apiary section chief for the Hawaii Department of Agriculture. “You’d have to go in your hive and you look inside the bee cells. It’d look almost like a brown melted larva instead of the pearly white C-shaped larva.”
A simple on-site test for American foulbrood involves sticking a small toothpick or twig into a bee cell. If the twig comes out with rope-like goo stuck to it, the hive is likely diseased.
“It also smells really putrid,” Rusert said. “It smells like a dead animal.”
Follow-up testing can be done in a laboratory to confirm diagnosis.
The Volcano case was found during a regular beekeeper inspection conducted by staff of the state’s Hawaii Apiary Program.
“We look for it any time we go into any hive; it’s first on the radar,” said Noelani Waters, one of the staffers on the site visit. “We have pretty trained eyes, so … we knew right away what we were looking at.”
“You can be a beekeeper for 20 years and have never seen this disease,” Rusert said. “There are probably a lot more cases out there, but we only visit so many beekeepers.”
American foulbrood has been in Hawaii for nearly 100 years. In the 1930s, a statewide outbreak nearly wiped out all of Hawaii’s honeybees.
“We had very viable honey production in Hawaii and it (American foulbrood) spread so fast,” said Corey Yost, who keeps hives in Keaau with her husband. “There just wasn’t enough information about what to do and what not to do.”
Yost is a member of the Big Island Beekeepers Association. During a meeting Monday, Waters gave an overview of American foulbrood and what steps beekeepers should take to protect their hives.
Notification of the new case also was sent to beekeepers via a voluntary registry managed by HAP. There are about 135 people on the Big Island who are part of the registry. Beekeeper names are kept confidential.
“Everybody should be in the ‘keep clean and don’t transfer anything’ stage,” Yost said. “It’s a heartbreaking disease because there’s really nothing you can do (if hives are infected).”
The spore is resistant to antibiotics, so treatment in that manner will keep bees alive but not rid a hive of the root bacteria. The hive weakens, but because it is still active, its honey and other resources remain in place.
“Other bees come and rob their hives for resources, and take it (American foulbrood) back to a healthy hive,” Rusert said. “The cycle just goes on and on.”
“We recommend burning the hive if it’s there, by digging a bonfire pit or a big hole around the hive,” she said. “Bees are pets to people; it’s really devastating.”
Email Ivy Ashe at iashe@hawaiitribune-herald.com.