ABSTRACT
Borrelioses are arthropod-borne illnesses that are caused by spirochetes of the Borrelia genus and that may be acquired world-wide. Two major fonns ofborreliosis are clinically manifest: 1) relapsing fevera febrile illness with a recurrent fever pattern but generally few other systemic manifestations for most patients, and 2) Lyme disease - a potentially multi-system illness that may have several clinical presentations depending on which organ system is sufficiently diseased. Both of these illnesses are modestly well-studied, especially Lyme disease which is endemic in most well-developed countries. Although borrelioses may be considered by some to be emerging diseases, they are by no means new infections. Indeed there are several early descriptions of each that have been published many decades or even a century before the discovery of the causative spirochete and the interest that has grown exponentially over the last two decades. Relapsing fever has been recognized on most continents, but citations of infection have been generally few on a yearly basis in westernized countries. Large outbreaks in underdeveloped Africa continue, but many outbreaks were recorded in the past, mostly associated with the military or the impoverished during times of war (1). Lyme spirochetes have been detected by genetic amplification techniques in"archived European ticks which date back to 1884 (2). Lyme disease was essentially recognized in its complexity by the 1980s when the etiological agent, Borrelia burgdoiferi, was discovered and then exploited for diagnostic purposes. Lyme disease is now both a fascinating disease and a relatively common illness in several regions of the world. Although there have been many interesting findings and publications that explored relapsing fever spirochetes much before the recent interest in Lyme disease, it was the emergence of the latter which placed research and endeavour in the area of borrelioses to the forefront. Whereas much of the exploratory science is contemporary, the spirochetes and their vectors are likely to have existed in nature for as long as animals have inhabited the earth. One can clearly attribute activity in this field to the new discoveries from the last two decades, but one must
one must acknowledge that growing and spreading human populations have also forced the contact of people with elements in nature to an unprecedented level.
