6,502
edits
Changes
→Treatment
Anthelmintic drugs are used in the control of fasciolosis. Not all flukicides are effective against each parasitic developmental stage, and so some may not be suitable for use in an outbreak of acute disease. Triclabendazole, a benzimidazole, is the flukicide with the broadest spectrum of activity against both immature and adult ''[[Fasciola hepatica]]'' and is therefore used to control acute disease. However, triclabendazole-resistant fluke populations are beginning to emerge. Albendazole, closantel, clorsulon and nitroxanyl all have a narrower spectrum of activity, primarily against adult fluke.
Anthelmintic drugs are used in the control of fasciolosis. Not all flukicides are effective against each parasitic developmental stage, and so some may not be suitable for use in an outbreak of acute disease. Triclabendazole, a benzimidazole, is the flukicide with the broadest spectrum of activity against both immature and adult ''[[Fasciola hepatica]]'' and is therefore used to control acute disease. However, triclabendazole-resistant fluke populations are beginning to emerge. Albendazole, closantel, clorsulon and nitroxanyl all have a narrower spectrum of activity, primarily against adult fluke.
There are two objectives to anthelmintic control of fluke in sheep and cattle. The first is to limit shedding of fluke eggs onto snail habitats, whcih is achieved by the use of any adulticidal drug in late winter/early spring. The second aim is to protect animals grazing metacercariae-contaminated pasture against fluke infection, and the approach to this is not so simplistic. Here, the choice of drug, the timing of treatment and dosing interval is dependent on: a) whether acute or chronic disease is the (anticipated) problem; b) the likely intensity of challenge, based on local knowledge or fluke forecasting and c)the peristence of the selected drug.
There are two objectives to anthelmintic control of fluke in sheep and cattle. The first is to limit shedding of fluke eggs onto snail habitats, whcih is achieved by the use of any adulticidal drug in late winter/early spring. The second aim is to protect animals grazing metacercariae-contaminated pasture against fluke infection, and the approach to this is not so simplistic. Here, the choice of drug, the timing of treatment and dosing interval is dependent on: a) whether acute or chronic disease is the (anticipated) problem; b) the likely intensity of challenge, based on local knowledge or fluke forecasting and c)the peristence of the selected drug. When treating for chronic fasciolosis, it is important to provide good quality nutrition following anthelmintic dosing.
Previously, molluscicides have been employed to control fasciolosis and were successful. Hoever, these are now infrequently used. This is in part due to the need for application before the likely impact of fluke can be predicted, potentially creating an uneccessary cost. Molluscides can also be difficult to use effectively since careful application is needed to avoid rapid recolonisation of treated land from any habitat that has been missed.
'''Alternative strategies'''
*An ability to recognise and define the extent of snail habitats allows alternative cost-effective control options such as fencing and drainage
If the fuke is present treat with triclabendazole, which is effective against all stages of Fasciola hepatica. Treatment should be applied in September/October and again in January, if faecal egg count is still postitive. One may also treat against adult only stages in May/June, preventing any future pasture contamination. However, do not use the same treatment in September/October as used in May/June, as resistance to drugs is becoming a real problem within the UK due to overuse. If it has been a particularly wet season, it may be necessary to treat again, as Fasciola hepatica becomes more prevalent under such conditions.
Isolation and treatment of all new animals entering from another farm has also be shown to be effective. Other control measures include fencing off wet areas, and increasing soil drainage.
'''Vaccination'''
'''Vaccination'''
*A recombinant vaccine providing approximately 70% protection for cattle is being developed
*A recombinant vaccine providing approximately 70% protection for cattle is being developed
*It exerts its effect by stimulating a range of immune responses not normally seen in chronically infected animals (including TH1-type responses)
*It exerts its effect by stimulating a range of immune responses not normally seen in chronically infected animals (including TH1-type responses)
==Prognosis==
==Prognosis==