Overview of bee diseases and available treatment options · Overview of bee diseases and available treatment options ... are able to survive and perform their mission usually falls

Medicines for bees - What can EMEA do to increase availabilityLondon, 14 and 15 December 2009

Overview of bee diseases andavailable treatment options

Overview of bee diseases andavailable treatment options

Vlasta JenčičVeterinary Faculty, University of Ljubljana

Slovenia


HeadlinesHeadlinesintroductiondiseases of a honeybee colony

brood diseases: American and European foul brood, chalkbrood, stonebrood, sacbroodadult bee diseases: nosemosis, viral diseases, varrosis, acarosis, tropilelosispest: small hive bettle (Aethina tumida)Colony Collaps Disorder - CCD

conclusions


Health of honeybee colony?Health of honeybee colony?

one queen, couple of ten thousands of workers of different ages (drones and brood) are able to survive and perform their missionusually falls ill one group of the honeybeecolony or one age group of workers

brood diseasesadult bee diseases


Defence mehanisms of individual beeDefence mehanisms of individual beeanatomical and physiological barriers

cuticle and hairtracheal systemperitrophic membrane of the midgut

nonspecific immunityhaemocytes production of interferon

natural and acquired resistance to certain pathogens


Defence mechanisms of the bee colonyDefence mechanisms of the bee colony

hygienic behaviourdetection and removal of sick and dead broodremoval of debris and dead bees

propolisation of foreign bodies antimicrobial activity of propolis, honey and pollenantimicrobial activity of royal gellyhoneybees usually die out of the hiveemergency swarmingmechanisms of Indian bees towards varroamechanisms of African bees towards small hive beetle


Insufficient defence mechanismsInsufficient defence mechanismspoor beekeeping technology, migratory beekeeping, insufficient foraging and malnutrition, pharmaceutical substances in the hive, unprofessional medical treatmenturbanisationenvironmental pollutionagricultural technology: using of pesticides, herbicides and acaricides, planting of monocultures, genetically modified plants?climate changing - global warming: unusual vegetation in the inappropriate timeglobal trade


Diseases and pests of honeybeesDiseases and pests of honeybees

infectious diseasesviral diseasesbacterial diseasesfungal diseasesparasitical diseases

pestsnon infectious diseases - colony disorders


Council Directive 92/65/EECCouncil Directive 92/65/EEC

lays down the provisions for intra -Community trade in beessets out the health certification requirements for the import of bees from third countriesnotifiable diseases are:

American foul brood Aethina tumida (the small hive beetle)Tropilaelaps miteVarroosisAcarapisosisEuropean foul brood


Acarapisosis of honey beesAmerican foulbrood of honey beesEuropean foulbrood of honey beesSmall hive beetle infestation (Aethinatumida) Tropilaelaps infestation of honey beesVarroosis of honey bees

Terrestrial Animal Health CodeTerrestrial Animal Health Code


American foul broodAmerican foul brood

Paenibacillus larvae subsp. larvae a spore forming bacteriahighly contagiousoccurs at any time when brood is presentcan kill a colonyspreads to other coloniesspores are able to survive for many yearsare very resistant to disinfectants


healthy capped brood pattern


Signs of American foul broodSigns of American foul broodcapped brood is affected wax caps are sunken, perforated, moist and darker


Signs of American foul brood - cont.Signs of American foul brood - cont.sick larvae are light to dark brown, amorphousand can stretch even up to 3 cm


Eradication - preventionEradication - preventionAmerican foul brood is a notifiable diseasetreatment is not possible; antibiotics do not kill very resistant sporesantibiotics are not alloweddestruction of infected colonies is compulsoryproper preventing measures should be employed

maintenance of beekeeping hygiene regular examination of colonies


European foul broodEuropean foul broodMelissococcus pluton and many secundary bacteria: Paenibacillus alvei, Enterococcus faecalis, Brevibacillus laterosporus, Lactobacillus euridicethe disease could be serious or it disappearsusually it is stress-relatedno treatment - eradication - the same as American foul broodin some countries antibiotic treatment is permitted under certain circumstances: supervision byveterinarians and taking into account long withdrawal period: up to six month


Signs of European foul broodSigns of European foul brooduncapped brood is affected; larvae are twisted, yellow to brown and remain segmented


ChalkbroodChalkbroodis caused by the fungus Ascosphaera apisit invades larvae and kills them when they have been cappedaffected larvae release millions of spores they adhere to combs and to adult beesfungus can remain infectious for long timeno medical treatmentmaintaining good beekeeping hygiene andstrong colonies is the best way of the control


Signs of chalkbroodSigns of chalkbroodinfected larvae are hard, chalky-white andmottled grey to blackwe can see dead larvae on the floor at thehive entrance


StonebroodStonebroodis caused by the fungus Aspergillus flavusand A. fumigatuspathogenic also to adult bees and other insects, birds and mammalsaffected brood is mummifiedmummies are hard and solid as a stone

zoonosis - beekeepers should protect themselvesurgent destruction of the affected colonies!


is disease caused by the virus Moratoraetatulaeinfected larvae do not pupate and remain stretched with heads towards the top of their cellsthere is no specific treatmentif much of the brood is affected the queen should be replaced from the uninfected colony

SacbroodSacbrood


Signs of sacbroodSigns of sacbrood

typical gondola shape infected larva which iseasily removed


Viral diseasesViral diseasesChronic Paralysis Virus

abnormal trembling motion of the wingshave reduced body hair, appear darker and shiny

Acute Paralysis Virusis more virulentaffected bees die quickly

Israeli Acute Paralysis Virus (2004)strongly related to Colony Collaps Disorder (CCD)

many others viruses…no medical treatment


NosemosisNosemosisis a disease of the digestive tract caused by a spore forming protozoan Nosema apischronic infection weakens the bees, shortens the productive life of the workers, and reduces their ability to produce brood foodresult is a decreased honey productionqueen and drone activities are reducedacute infection results in dysentery, defecating in the hive and increased winter losses


Nosemosis - contNosemosis - cont

Nosema apis is present in most apiaries; even if the infection is not obvious it causes significant damage in apicultureis highly contagious and it spreads in the bee colony, within the colonies and withmigrating beekeeping to long distancesimproper beekeeping technology increases the risk of the disease and bee loses and decreasing of the production


Nosemosis - Nosema ceranaNosemosis - Nosema cerana

primarly parasite of Asian bee Apis cerana1994 on Apis mellifera in Spain2006 in France, Germany, United StatesN. cerana and N. apis differ on spore morphology; they are recognised by genetic sequencingN. cerana is more virulent than N. apisit is linked (not yet proved) to the Colony Collapse Disorder


TreatmentTreatmentFumagillin produced by fermentation of Aspergillus fumigatus is highly effective to the vegetative stage N. apis

possible site effects on human healthno MRLs established in the EU countries it is (was) not allowed

research of the alternative methods of treatmenttransfering the infected colony to disenfectedcombs and hive is the best control measure


PreventionPreventionmaintaining strong and vital bee coloniesregular replacment of the old combsdisinfection of combs and equipmentarranging proper water suppliesproper feeding and food suppliesavoiding disturbing colonies during winterregular checking the infection and thediseasemany others….


VarrosisVarrosiscaused by the mite Varroa destructor - varroaoriginaly parasite of Asian honeybees Apiscerana which have developed natural resistancevarroa feeds with hemolimfe of bees and larvae - prefers drone brood; larvae and bees are weakened and less immunocompetentvarroa could be a vector of other bee pathogenesif we do not help, honeybee colony dies within 1 to 3 years


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developementof V. destructor

Source: http://maarec.psu.edu/pest&disease/pest13.gif


Signs of varrosisSigns of varrosisheavy infested pupas die and are removedif they survive, bees show different body deformationsare smaller and less vitalare less resistant to other diseaseshave shorter life


Signs of varrosis on bee colonySigns of varrosis on bee colonyreduced number of adult beesneglected and dead brood, abnormal brood patternmany varroa in the hive


Control strategyControl strategyinfected bee colonies cannot recoverthe mite population has to be kept within such a level that colony is not biologically and economically affectedthe biology of honeybee, varroa and their interactions has to be fully understoodbeekeeping management has to be understoodthe level of varroa infestation has to be monitored regularly


Control strategy - cont.Control strategy - cont.control is demanding because the host and the parasite are similar in their biology varroa is in the cupped brood majority of the lifemore than the method, proper organisation of the control is important:

all beekeepers in the area should treat varroa at the same time with the same medicine

it is necessary to mind the quality of honeybee productsit is necessary to mind beekeeper safety - the protective clothes are obligatory


Control methodsControl methods

biotehnical methodsdrone brood removalcomb trapingmanny others

use of chemicalssynthesised chemicalsnatural substances

combination of both - integrated varroa controlproblem - not authorised substances!


Medicines have to be authorisedMedicines have to be authorised

authorisation requires an exact scientific evaluation to prove that the medicine is not harmful to the:

consumersbeekeepershoneybeesenvironment


Authorisation Authorisation EMEA - European Agency for the Evaluation of Medical ProductsCVMP - Committee for Veterinary Medical ProductsMRLs for all the veterinary drugs should be established - some exceptionsanimals are divided into the major / minor use and the major / minor species - MUMS; also honeybees are included for the MUMS already obtained data could be evaluated or can be acquired from the academic or other institutes and estimated by the CVMP


ResistenceResistence

Source: http://beebase.csl.gov.uk/pdfs/managing_varroa.pdf


Some substances evaluated by EMEASome substances evaluated by EMEA

IIThymolIIOxalic acidIIMentholIILactic acidNo recemendationFumagillinIIFormic acid

HoneyIIFlumetrin (Bayvarol)Honey1000IIICymiazole (Apitol)Honey100ICoumaphos (Perizin)Honey200IAmitraz (Apivar)

FoodMRL (ppb)AnnexVeterinary drug


Acarine disease - Acaraposis apiumAcarine disease - Acaraposis apium

mite Acarapis woodi (Rennie) completes its life cycle within the prothoracic tracheae of young bees andfeeds with hemolimfemites can be observed under microscopemale: 11-12 days; female: 14-15 daysinfestation is not obvious during summer time, but it spreads among the bees in the colony; the infested bees have a shorter life span


Signs of acarine diseaseSigns of acarine disease

are obvious late in winter and early in spring when bees begin to fly out of the hive bees cannot fly, they crawl and die if the winter is long there are not enough bees to maintain the temperature in the winter cluster, and the entire colony diestreatment: today it would be possible to use the medicines for systemic varroa treatment

in EU the disease does not pose a problemcurrently!


darkened infestedtracheaeobstructed by mites in various developmentstages


Tropilelaps infestation of honeybeesTropilelaps infestation of honeybeesmites from the genes Tropilelaps are parasites of honeybee brood primarily of Apis dorsataTropilelaps clarae and T. mercedesae are damaging pests also to Apis melliferaan infestation can be easily recognised either visually on bees or by examining hive debrisclinical signs of the disease are similar to varrosistreatment is similar to that of varroa

it is an exotic diseases to EU; the contingency plan should be provided


Small hive beetle (Aethina tumida)Small hive beetle (Aethina tumida)

an exotic pest to EU (probably Portugal, 2004); a serious threat to European apicultureit multiplies in the infested colony and destroys combs and colonyits origin is in Africa where it does not cause much harm, however in America where it was introduced in 1998 has already destroyed thousands of coloniestreatment is similar to that of varroain EU the contingensy plan should be provided


Colony Collapse Disorder - CCDColony Collapse Disorder - CCDmysterious honeybee disease (syndrome) of theworldwide concernsudden disappearance of beesno dead bees inside or around the hivequeen and brood are leftpollen and honey are not robbedminimal evidence of wax moth

probably combination of many factors all losses are not CCD


ConclusionsConclusionswe need different beekeeping strategy

different feeding programmore frequent comb changeseducation of beekeepers

more research on honeybee biology and physiologymaybe we are not always right

research on honeybee medicinesalternative treatmentsthe methods should be in accordance of honeybee biologymore experimentsare honey bees really “MUMS”


Bees are a type of fly, hardworking, createdby God to provide man with all neededhoney and wax. Amongst all God's beingsthere are none so hard working and usefulto man with so little attention needed forits keep as the bee.

Anton Janša (1734-1773)


Thank you for Your attentionThank you for Your attention


SourcesSourcesGliński Z., Jarosz J.:Infection and immunity in the honeybee Apis mellifera, Apiacta, 2001, 36 (1), 12 - 24 http://www.utahcountybeekeepers.org/Other%20Files/Information%20Articles/Managing%20Varroa%20UK%20Article.pdfhttp://www.fdbka.co.uk/foul.pdfhttp://en.wikipedia.org/wiki/Diseases_of_the_honey_beehttp://en.wikipedia.org/wiki/Anton_Jan%C5%A1aothers

Overview of bee diseases and available treatment options · Overview of bee diseases and available treatment options ... are able to survive and perform their mission usually falls

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