Robert S. Lane
Professor and Entomologist
411 Wellman Hall
Phone #: (510) 642-4385
FAX #: (510) 642-7428
blane@nature.berkeley.edu
Research Interests
We have been studying the ecology, epidemiology and control of tick-borne
diseases, particularly the spirochete (bacterium) that causes Lyme disease
(LD). LD is currently the most commonly reported vector-borne infection
in California, the United States, and in other temperate regions of the
world. The broad objectives of this research are intended to clarify the
basic mechanisms by which the LD spirochete is maintained and distributed
including the various modes of transmission to humans and other animals;
to determine what behavioral and environmental factors place people at risk
for acquiring this spirochete; and to evaluate control methodologies for
reducing such risk.
We found that the LD spirochete is maintained in a transmission cycle that
differs basically from that in the upper midwestern and northeastern United
States. Woodrats and kangaroo rats (vs. white-footed mice) serve as reservoir
hosts, 3 species of ticks (vs. one species) maintain and distribute the
spirochete, and the spirochetes themselves are generally much more variable
than those from the East. Factors that contribute to risk of infection include
cutting wood, exposure to leaf litter in hardwood forests, and other outdoor
activities that place people in direct contact with the habitats of the
primary tick vector. These findings underscore the need for vector ecologists
and epidemiologists to study the disease on a regional basis before locally
effective control methodologies can be developed and implemented to protect
human health.
Additionally, a new species of tick-borne spirochete was discovered during
these studies that may be the cause of epizootic bovine abortion, a disease
that has been estimated to cause annual losses of $5-15 million to the cattle
industry in California alone. Other tick-borne diseases currently or previously
investigated by us in collaboration with others include Colorado tick fever,
Rocky Mountain spotted fever, ehrlichiosis, relapsing fever, tularemia,
human babesiosis, and tick paralysis.
Current Projects
Several ongoing projects are aimed at expanding our knowledge of the
relationship of various isolates of LD spirochetes (and other microbial
agents) to their tick vectors and vertebrate hosts. Spirochetes isolated
from ticks and wildlife are being characterized antigenically and genetically,
and the infectivity of selected isolates for vertebrates and ticks determined.
The ability of human and nonhuman-biting ticks to acquire, maintain, and
transmit the LD spirochete, and the role of rodents and lizards in perpetuating
it, are being evaluated experimentally as well as in the field. Intrinsic
and extrinsic factors that contribute to the vector efficiency of different
ticks and the reservoir competence of rodents also are being assessed. Life
history studies of all stages of the western black-legged tick, the primary
vector of the LD spirochete to humans in the Far West, are under way preparatory
to modelling the population dynamics of this important vector.
Another current focus is to elucidate human risk of exposure to vector ticks
along hiking trails and in picnic areas of several heavily-used parklands
and other recreational areas in the San Francisco Bay region. Moreover,
peridomestic exposure to vector ticks is being evaluated ecologically and
seroepidemiologically in rural communities endemic for LD.
The ultimate goal of this research is to use the basic knowledge gleaned
from the foregoing projects to develop and implement strategies for reducing
human exposure to tick-borne agents. One method currently being tested is
the delivery of an oil-based formulation of permethrin to wild rodents via
bait stations to reduce the abundance of their associated vector ticks.
Another method being evaluated for the same purpose is the use of prescribed
(controlled) burning in brushlands where ticks abound. It is anticipated
that either one or both of these methods may eventually prove to be useful
as part of an integrated program for reducing tick abundance in rural settings
or where suburbs abut on natural areas.
Selected Publications
Lane, R.S., Burgdorfer,W., Hayes, S.F., and Barbour, A.G. 1985. Isolation
of a spirochete from the soft tick, Ornithodoros coriaceus: a possible agent
of epizootic bovine abortion. Science 230:85-87.
Lane, R.S., Piesman, J., and Burgdorfer, W. 1991. Lyme borreliosis: relation
of its causative agent to its vectors and hosts in North America and Europe.
Annu. Rev. Entomol. 36:587-609.
Brown, R.N. and Lane, R.S. 1992. Lyme disease in California: a novel enzootic
transmission cycle of Borrelia burgdorferi. Science 256:1439-1442.
Lane, R.S., Manweiler, S.A., Stubbs, H.A., Lennette, E.T., Madigan, J.E.,
and Lavoie, P.E. 1992. Risk factors for Lyme disease in a small rural community
in northern California. Am. J. Epidemiol. 136:1358-1368.
Persing, D.H., Herwaldt, B.L., Glaser, C., Lane, R.S., Thomford, J.W., Mathiesen,
D., Krause, P.J., Phillip, D.F., and Conrad, P.A. 1995. Infection with a
Babesia-like organism in northern California. N. Engl. J. Med. 332:298-303.
Current Graduate Students:
- Kurstin Graham
- Ted Slowik
- Douglas Kain
- Caryl Waggett
Current Postdoctoral Fellow:
Current Staff Research Associates:
- Leslie Casher
- Esther Omi-Olsen
- Joyce Kleinjan
- Kerry Padgett
- Mary Mesirow
- Judith Pascocello