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From the 1995 International Lyme Conference held in Vancouver BC
Satyendra Nath Banerjee, MD
Head, Vector-borne Diseases
British Columbia Centre for Disease Control
Isolation of Borrelia burgdorferi in British Columbia During 1992-1994
S.N. Banerjee, M. Banerjee, K. Fernando, M.Y. Dong, M. Altamirano and J.A. Smith. Provincial Laboratory, BC-CDC
The survey of ticks in B.C. during 1988 to 1991 was limited to adult ticks. In 1992 we began trapping rodents in 20 selected sites and juvenile ticks were retrieved from them. Tick guts as well as six organs from rodents, viz., ear, bladder, kidney, spleen, liver and heart were cultured in BSK II medium with antibiotics. All isolates were immunostained with Mab for P31, P34, P39 and P41 ag. SDS-PAGE profiles, PCR for OSPA gene and DNA sequence of 16SrRNA gene were analyzed for all axenic cultures. Up to 1991 when we had only adult ticks for culture, no spirochete was isolated 0/1360 (0%). In 1992 B. burgdorferi (Bb) was isolated from 1/539 (0.2%) ticks and 0/28 (0%) mice. In 1993 20/2086 (1%) ticks and 11/243 (4.5%) mice had Bb. In 1994, 7/691 (1%) ticks and 9/211 (4.1%) mice had Bb. SDS-PAGE protein profiles of isolates were comparable to that of Bb. All Bb were positive by Mab tests and by PCR for OSPA. DNA sequences of 16SrRNA gene were similar to Bb-B31. Bb was isolated from I. angustus and I. pacificus ticks. The presence of spirochetes in juvenile and adult ticks as well as in rodents suggests establishment of Bb in B.C. Our results show that culture of host organs and culture of juvenile ticks retrieved from hosts may be more successful than culture of adult ticks only.
Patricia Daly, MD, FRCPC
Associate Director, Epidemiology
B.C. Centre for Disease Control
Lyme Disease in British Columbia
Patricia Daly(1), Satyen Banerjee(2), Craig Stephen(1) (1) Communicable Disease Epidemiology Services, British Columbia Centre for Disease Control; (2) Provincial Laboratory, British Columbia Centre for Disease Control
In June, 1994, borreliosis was made a reportable disease under the Communicable Disease Regulations of the Health Act in the province of British Columbia. This action was taken because of several pieces of evidence. Since 1988, there have been several cases of clinically suspected Lyme disease with positive serology for Borrelia burgdorferi who appear to have acquired Lyme disease from within the province. At the same time, studies have identified the presence of tick species in British Columbia that are known to transmit B. burgdorferi. Further studies, which are ongoing, have revealed the presence of B. burgdorferi in several tick species form the southwest coastal regions of the province, as well as in deer mice hosts. The case definition to be used for reporting purposes is that developed by the Canadian consensus conference on Lyme disease in 1991 (CDWR 1991; 17(13):66). Based on the Canadian consensus conference guidelines, British Columbia is considered an endemic area for Lyme disease, although the geographical boundaries for endemicity have not been defined and will require further study.
Raj Gill, BSc
Health Science Officer, Provincial Laboratories
B.C. Centre for Disease Control
Lyme Disease Cases Acquired in British Columbia 1992-1994
Raj Gill, Satyendra Banerjee and Maya Banerjee
Research on Lyme borreliosis in British Columbia has been on going since 1986. Our first positive case was a 2 year old female from Burns Lake in 1988. Two patients were found to be positive in 1989; a 44 year old female from Salt Spring Island and a 71 year old female form Galiano Island. Only on 46 year old male was positive in 1992 from Kootenay Lake. In 1993, three cases were reported; one 58 year old female from Oliver, a 74 year old female from Nanaimo and a 66 year old male from Cortes Island. As of October 1994 4 cases have been confirmed; two males from Agassiz and Lumby and 2 females form Port Coquitlam and Port Moody. This makes a total of 11 cases of Lyme disease acquired in B.C. during 1988-1994 out of a total of 43 cases seen at the Provincial Laboratory, B.C.C.D.C. Only 2 cases showed the classical EM rash, most patients were febrile with headache, fatigue and muscle pain. Elderly patients presented with arthralgia and myalgia. All patients were positive by the ELISA method and confirmed by Western Blot sets and clinical diagnosis by physicians. It is pertinent to note that during 1993-94 Dr. S. Banerjee's Vector Borne Disease Laboratory isolated B. burgdorferi the etiologic agent from the deer mice Peromyscus maniculatus and two species of ticks viz. Ixodes pacificus and I. angustus collected from the places where cases were identified. On the basis of our findings and the Lyme disease consensus report on case definitions, B.C. should be considered an endemic area for Lyme disease.
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