Honeybees are a primary pollinator of plants, including crops, fruits and vegetables. Our diets rely greatly on the work that bees do – in addition to the honey and wax bees produce themselves.
Sadly certain pesticides have been used in the past that affected bees negatively, although more recently governments have begun to ban such chemicals.
Bees are also susceptible to diseases and parasites. American or European Foulbrood can destroy a hive and, if unchecked, can spread between multiple hives.
However, varroa mites are the most common health problem for bees – a parasite which attaches to a bee larva and stays with it, sucking its blood and reducing its lifespan and effectiveness to the colony.
In recent years new treatments have been released to treat for varroa, some of which are easy to use and very effective.
http://www.nationalbeeunit.com has more information on bee health and action to take.