Among 30 Borrelia known species, Borrelia afzelii is one of four which are likely to infect humans causing a variant of Lyme disease.
Borrelia afzelii is a species of Borrelia, a bacterium that can infect various species of vertebrates and invertebrates. B. afzelii and B. garinii are the primary causes of Lyme disease in Europe and Asia. Coinfection by this Borrelia species with one or more pathogens can occur, carried by the vector, which appears to be in most cases the tick. In Europe the related genospecies Borrelia afzelii is associated with both EM and acrodermatitis chronica atrophicans (ACA), and several European studies have found compelling evidence for B. afzelii infection in patients with morphea.
EM stands for Erythema migrans which is a rash that frequently appears as one of the first symptoms of Lyme disease. It's typically a circular red area that sometimes clears in the middle, forming a bull's-eye pattern. It can spread up to 12 inches across and may be warm to the touch. It's not usually itchy or painful and may appear in more than one place on the body.
Approximately 70% to 80% of people with Lyme disease, which is spread by ticks, will develop erythema migrans. It will usually show up at the site of a tick bite within 3 to 30 days after being bitten. It will gradually expand, although it doesn't always appear the same on everyone.
ACA stands for Acrodermatitis chronica atrophicans and is the third or late stage of European Lyme borreliosis. This unusual progressive fibrosing skin process is caused by an ongoing active infection with Borrelia afzelii.
Borrelia afzelii p100 - IgG
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