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and this is applicable too. Lyme/Borreliosis in Deer Stalkers in the UK Lyme/Borreliosis is a zoonotic disease spread by the bite of a tick infected with spirochaetal bacteria Borrelia species (which apart from the normal nucleolar DNA have plasmids . These are separate entities of DNA in the body of the bacteria) Ticks have a 3 stage lifecycle over a 3 year period. Eggs hatch into larvae (6 legs) blood meal,nymph (8 legs ) blood meal,adult (8 legs) blood meal egg laying. If at any stage the ticks pick up an infection that line of ticks carry the infection through all stages ( vertical transmission ) blood meals are normally taken from mammals and birds When an infected tick bites a patient, say human a sequence of events takes place.Borrelia species are attached to the tick gut and the blood releases them to move to the salivary glands ( tick moves from ground temperature to body heat ) Simultaneously the outer surface protein changes from OSP A to OSP C. This is the reason the tick must be attached for 36 hours or more Tick saliva is anaesthetic,anticoagulant and contains a protein SALP15 ( homologues in Ixodes ricinus ticks) which coats the bacteria as they pass into the host's body and is disseminated by the blood throughout the body. This protein protects the bacteria from triggering an immediate immune response.This is a SIGNIFICANT FEATURE Borreilia bacteria causing disease Borrelia burgdorferi ( Bb ).....mainly arthritis Borrelia garinii ( Bg )...mainly nervous Borrelia afzelii ( Ba )...mainly skin newly diagnosed species Borrelia valaisiana ( Bv )...skin ? Borrelia spielmanii ( Bs )....skin ? Symptoms of Lyme/Borreliosis Stage 1 Early localised disease. Symptoms start one to two weeks after the tick bite. Earliest sign is Erythema migrans so-called " bull's eye " rash.A central spot of red which is warm to touch. not raised and non painful, as it progresses outwards centre goes pale. This is pathognomonic (definite Lyme /Borreliosis ) Only occurs in 30-80 % of cases.A blood sample at this stage is useless as body immune response delayed ( refer SALP15 ) FALSE NEGATIVE Stage 2 Early disseminated Lyme/Borreliosis Occurs weeks after the tick bite. Flu like symptoms Chills Fever Sweating Enlarged lymph glands Vision changes Sore throat Fatigue headaches General malaise Rash may appear over the body other than the position of the tick bite Neurological signs Numbness, tingling in muscles, Bell's palsy and cardiac disturbance Stages 1 and 2 can overlap. Stage 3 Late disseminated disease Severe headaches Arthritis in one or more large joints Disturbance of heart rhythm Short term memory loss Difficulty concentrating Mental fogginess Problems following conversations Numbness in arms,legs,feet Diagnosis CLINICAL EM diagnostic Blood tests Elisa initial test confirmed by Western blot polymerase chain reaction PCR As the symptoms are non specific mainly full history and lifestyle assessment is paramount. If in doubt treat. Recommended treatment high dose doxycycline. Most effective 200mg twice daily for a month. Precautions. Photosensitisation protect against strong light.No alcohol. Marmite to supplement gut products lost by gut sterilisation Criticisms of diagnostic criteria Blood samples submitted to laboratory are taken before antibodies develop ( delayed immune response ) Specific challenging material ( probes ) Bg has 7 different serovariants Dedicated protocols: American protocols not appropriate for European diagnoses Lyme/Borreliosis is the most common tick borne disease in Europe, must be taken seriously as grossly under diagnosed Only in Scotland and Rep of Ireland a notifiable disease not rest of UK Reference papers Clinical Microbiology Review 2005 July 18 (3) 484-509 Journal of Clinical Microbiology Dec 1999 vol 37 no 12 4086-4092 J Clin Micro 2014 Oct 52 (100 3755-3762 J Clin Micro 2000 June vlo 38 no6 2097-2102 FEMS Immun Med Microbiology 49 ( 2007 ) 13-21 Clinical Infectious Diseases 2013 57 93) 333-340 |