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American foulbrood (AFB, Histolysis infectiosa perniciosa larvae apium, Pestis americana larvae apium), caused by the spore-forming bacterium Paenibacillus larvae , [lower-alpha 1] is a highly infectious honey bee brood disease. It is the most widespread and destructive of the honey bee brood diseases. It is globally distributed and burning of infected colonies is often considered as the only effective measure to prevent spreading of the disease.
Paenibacillus larvae is a rod-shaped bacterium visible only under a high power microscope. Larvae up to three days old become infected by ingesting spores present in their food. Young larvae less than 24 hours old are most susceptible to infection. Spores germinate in the gut of the larva and the vegetative form of the bacteria begins to grow and multiply until the midgut is massively filled with bacteria, resulting in a shortage of nutrients (commensal non-invasive phase). This is when P. larvae breaks through the midgut wall and enters the hemocoel of the larva, accompanied by the death of the larva (invasive phase). Now, the bacteria take nourishment from the dead larva and decompose it into a ropy mass (saprophytic phase). Once this decomposition results in a second shortage of nutrients, P. larvae produces millions of spores. The ropy mass dries down to a characteristic scale. This disease does not affect adult honey bees, but is highly infectious and deadly to bee broods. [3] [4]
Until 1906 American foulbrood was not differentiated from European foulbrood, and the condition was simply referred to as foulbrood. Thereafter, the terms European and American were used to distinguish the diseases. [5] However, the designations do not refer to the geographical distributions but to the areas where they were first investigated scientifically. [6] In 1907, it was demonstrated conclusively that the bacterium Bacillus larvae was the cause of American foulbrood disease by fulfilling Koch's postulates. [7] The geographical origin of AFB is unknown, but it is found almost worldwide. [8] [9]
Lab testing is necessary for definitive diagnosis, but a good field test is to touch a dead larva with a toothpick or twig. It will be sticky and "ropey" (drawn out). Foulbrood also has a characteristic odor, and experienced beekeepers with a good sense of smell can often detect the disease upon opening a hive. [10] However, this odour may not be noticeable until the disease is in an advanced stage. Since response and treatment is required as early as possible to protect other colonies, absence of odour cannot be relied on as indicating absence of foulbrood. Only regular and thorough inspection of the brood can identify the disease in its early stages. The most reliable disease diagnosis is done by sending in some possibly affected brood comb honey to a laboratory specialized in identifying honey bee diseases. [11]
When cleaning contaminated cells, bees distribute spores throughout the colony. Disease spreads rapidly throughout the hive as the bees, trying to remove the spore-laden dead larvae, contaminate brood food. Nectar stored in contaminated cells will contain spores and soon the brood chamber becomes filled with contaminated honey. As this honey is moved up into the supers, the entire hive becomes contaminated with spores. When the colony becomes weak from AFB infection, robber bees may enter and take contaminated honey back to their hives, thereby spreading the disease to other colonies and apiaries. [12] Beekeepers also may spread disease by moving equipment (frames or supers) from contaminated hives to healthy ones.
American foulbrood spores are extremely resistant to desiccation and can remain viable for more than 40 years in honey and beekeeping equipment. Therefore, honey from an unknown source should never be used as bee feed, and used beekeeping equipment should be assumed to be contaminated unless known to be otherwise. [13] [14]
European Union law requires all infected hives and equipment to be destroyed. [15] In the US, many State Apiary Inspectors require an AFB diseased hive to be burned completely. The spores can survive up to 40 years and are difficult to destroy.
A less radical method of containing the spread of disease is burning only the frames and comb and thoroughly flame scorching the interior of the hive body, bottom board and covers. Dipping the hive parts in hot paraffin wax or a 3% sodium hypochlorite solution (bleach) also renders the AFB spores innocuous. [16] It is also possible to sterilize an infected hive without damaging either the structure of the hive or the stores of honey and pollen it contains by sufficiently lengthy exposure to an atmosphere of ethylene oxide gas, as in a closed chamber, as hospitals do to sterilize equipment that cannot withstand steam sterilization. [17]
Antibiotics, in non-resistant strains of the pathogen, can prevent the vegetative state of the bacterium forming. Drug treatment to prevent the American foulbrood spores from successfully germinating and proliferating is possible using oxytetracycline hydrochloride (Terramycin). [18] Another drug treatment, tylosin tartrate, was approved by the US Food and Drug Administration (FDA) in 2005. [19]
Chemical treatment is sometimes used prophylactically, but this is a source of considerable controversy because certain strains of the bacterium seem to be rapidly developing resistance. [20] In addition, hives that are contaminated with millions of American foulbrood spores have to be prophylactically treated indefinitely. Once the treatment is suspended, the American foulbrood spores germinate successfully again leading to a disease outbreak.
Alternative treatments are currently under investigation. One example is phage therapy. [21] Another promising approach might be the use of lactic acid-producing bacteria as a treatment for AFB. [22] [23] [24] [25] [26] However, further research is still indispensable to prove the effectiveness of these methods in the field.
In January 2023, the United States Department of Agriculture approved the world's first vaccine for bees. The vaccine protects the bees from foulbrood and is dispensed by adding an inactive version of the bacteria to royal jelly consumed by worker bees, who feed the queen bee, who in turn passes immunity to her offspring. It was developed by biotech company Dalan Animal Health. [27]
Bees are winged insects closely related to wasps and ants, known for their roles in pollination and, in the case of the best-known bee species, the western honey bee, for producing honey. Bees are a monophyletic lineage within the superfamily Apoidea. They are currently considered a clade, called Anthophila. There are over 20,000 known species of bees in seven recognized biological families. Some species – including honey bees, bumblebees, and stingless bees – live socially in colonies while most species (>90%) – including mason bees, carpenter bees, leafcutter bees, and sweat bees – are solitary.
A beehive is an enclosed structure in which some honey bee species of the subgenus Apis live and raise their young. Though the word beehive is used to describe the nest of any bee colony, scientific and professional literature distinguishes nest from hive. Nest is used to discuss colonies that house themselves in natural or artificial cavities or are hanging and exposed. The term hive is used to describe an artificial/man-made structure to house a honey bee nest. Several species of Apis live in colonies. But for honey production, the western honey bee and the eastern honey bee are the main species kept in hives.
Beekeeping is the maintenance of bee colonies, commonly in man-made beehives. Honey bees in the genus Apis are the most commonly kept species but other honey producing bees such as Melipona stingless bees are also kept. Beekeepers keep bees to collect honey and other products of the hive: beeswax, propolis, bee pollen, and royal jelly. Other sources of beekeeping income include pollination of crops, raising queens, and production of package bees for sale. Bee hives are kept in an apiary or "bee yard".
An apiary is a location where beehives of honey bees are kept. Apiaries come in many sizes and can be rural or urban depending on the honey production operation. Furthermore, an apiary may refer to a hobbyist's hives or those used for commercial or educational usage. It can also be a wall-less, roofed structure, similar to a gazebo which houses hives, or an enclosed structure with an opening that directs the flight path of the bees.
A queen bee is typically an adult, mated female (gyne) that lives in a colony or hive of honey bees. With fully developed reproductive organs, the queen is usually the mother of most, if not all, of the bees in the beehive. Queens are developed from larvae selected by worker bees and specially fed in order to become sexually mature. There is normally only one adult, mated queen in a hive, in which case the bees will usually follow and fiercely protect her.
Bee pollen, also known as bee bread and ambrosia, is a ball or pellet of field-gathered flower pollen packed by worker honeybees, and used as the primary food source for the hive. It consists of simple sugars, protein, minerals and vitamins, fatty acids, and a small percentage of other components. Bee pollen is stored in brood cells, mixed with saliva, and sealed with a drop of honey. Bee pollen is harvested as food for humans and marketed as having various, but yet unproven, health benefits.
In beekeeping, a Langstroth hive is any vertically modular beehive that has the key features of vertically hung frames, a bottom board with entrance for the bees, boxes containing frames for brood and honey and an inner cover and top cap to provide weather protection. In a Langstroth hive, the bees build honeycomb into frames, which can be moved with ease. The frames are designed to prevent bees from attaching honeycombs where they would either connect adjacent frames, or connect frames to the walls of the hive. The movable frames allow the beekeeper to manage the bees in a way which was formerly impossible.
Nosema apis is a microsporidian, a small, unicellular parasite recently reclassified as a fungus that mainly affects honey bees. It causes nosemosis, also called nosema, which is the most common and widespread of adult honey bee diseases. The dormant stage of N. apis is a long-lived spore which is resistant to temperature extremes and dehydration, and cannot be killed by freezing the contaminated comb. Nosemosis is a listed disease with the Office International des Epizooties (OIE).
Varroa destructor, the Varroa mite, is an external parasitic mite that attacks and feeds on honey bees and is one of the most damaging honey bee pests in the world. A significant mite infestation leads to the death of a honey bee colony, usually in the late autumn through early spring. Without management for Varroa mite, honey bee colonies typically collapse within 2 to 3 years in temperate climates. These mites can infest Apis mellifera, the western honey bee, and Apis cerana, the Asian honey bee. Due to very similar physical characteristics, this species was thought to be the closely related Varroa jacobsoni prior to 2000, but they were found to be two separate species after DNA analysis.
Aethina tumida,commonly known as small hive beetle (SHB), is a beekeeping pest. It is native to sub-Saharan Africa, but has spread to many other regions, including North America, Australia, and the Philippines.
This page is a glossary of beekeeping.
Galleria mellonella, the greater wax moth or honeycomb moth, is a moth of the family Pyralidae. G. mellonella is found throughout the world. It is one of two species of wax moths, with the other being the lesser wax moth. G. mellonella eggs are laid in the spring, and they have four life stages. Males are able to generate ultrasonic sound pulses, which, along with pheromones, are used in mating. The larvae of G. mellonella are also often used as a model organism in research.
Beekeeping in New Zealand is reported to have commenced in 1839 with the importing of two skep hives by Mary Bumby, a missionary. It has since become an established industry as well a hobby activity.
Colony collapse disorder (CCD) is an abnormal phenomenon that occurs when the majority of worker bees in a honey bee colony disappear, leaving behind a queen, plenty of food, and a few nurse bees to care for the remaining immature bees. While such disappearances have occurred sporadically throughout the history of apiculture, and have been known by various names, the syndrome was renamed colony collapse disorder in early 2007 in conjunction with a drastic rise in reports of disappearances of western honey bee colonies in North America. Beekeepers in most European countries had observed a similar phenomenon since 1998, especially in Southern and Western Europe; the Northern Ireland Assembly received reports of a decline greater than 50%. The phenomenon became more global when it affected some Asian and African countries as well. From 1990 to 2021, the United Nation’s FAO calculated that the worldwide number of honeybee colonies increased 47%, reaching 102 million.
Beekeeping is first recorded in Ireland in the seventh century. It has seen a surge in popularity in modern times, with the membership of beekeeping associations exceeding 4,500. The median average number of hives per beekeeper is three hives, while the average honey output per hive is 11.4 kg. The growth in the practice has occurred despite increased pressures on bees and beekeepers due to parasites, diseases and habitat loss.
Paenibacillus alvei is a species of bacteria within the order Bacillales. Like other species within the genus Paenibacillus, strains of this species grow in novel, vortex-like, or branched patterns. This species is associated with the honey bee disease European foulbrood.
Sacbrood virus or SBV disease is an infectious disease caused by the Morator aetatulas virus that affects honey bee larvae. When sick, the colony declines gradually with few or no replacement workers, costing 20-80% of honey production.
Heather Hendrickson is a microbiologist and an Associate Professor in the School of Biological Sciences at the University of Canterbury in Christchurch, New Zealand. She previously worked at Massey University, Auckland, New Zealand. Her research is focussed on the evolution of bacterial cell shape, and the discovery of bacteriophages that can attack antibiotic-resistant bacteria and the bee disease American foulbrood.
Paenibacillus larvae is a species of bacterium, found worldwide, which causes American foulbrood, a fatal disease of the larvae of honeybees. It is a Gram-positive, rod-shaped bacterium, which forms spores which can remain viable for at least thirty-five years.
