Lyme spirochetes have been found in ticks at the British Museum-from 1896!!

    Charing Cross and Westminster Medical School, Department of
Biochemistry, London, U.K.

    The distribution of Borrelia burgdorferi sensu lato, the Lyme
borreliosis agent, was surveyed in British ticks in the collection of
the Natural History Museum, London. Alcohol-preserved specimens of
eight species of ticks known to attack humans were studied: Ixodes
ricinus, I. hexagonus, I. uriae, I. trianguliceps, Dermacentor
reticulatus, Haemaphysalis punctata, Rhipicephalus sanguineus and
Argas vespertilionis. The sample comprised all life stages and
originated from a wide range of host species, collection dates
(1896-1994) and geographical localities in England, Scotland and
Wales. Borrelia burgdorferi s.l. DNA, detected by a polymerase chain
reaction that targeted the outer surface protein A gene, was found in
all eight species.

The overall proportion of PCR-positive specimens ranged from 7.8% for I.
hexagonus (mostly from mustelids and hedgehogs) to 98.3% for I. uriae
(mostly from seabirds). Borrelia burgdorferi s.l. DNA was found for the
first time in the bat parasite A. vespertilionis (85.3%). The spirochaete
is newly recorded in British populations of I. trianguliceps (97.4%,
mostly from voles, mice and shrews), D. reticulatus (12.5% from dog and
man) and R. sanguineus (30% from dogs and human dwellings). Of the four
tick species with larvae available for testing, examples of I. ricinus, I.
uriae and A. vespertilionis were PCR positive, as were significantly more
nymphs than adults of I. ricinus, I. hexagonus and A. vespertilionis.
Analyses showed that B. burgdorferi s.l. has been consistently present in
British tick populations since at least 1897. Ticks positive for B.
burgdorferi s.l.

DNA were collected in all months of the year, throughout Britain, and were
found on a wide range of mammal and bird species. PCR positivity does not
prove vector or reservoir competence, but the use of archived material has
demonstrated an extensive range of host-tick relationships involving B.
burgdorferi s.l. in Britain for > 100 years.