As some experiments suggest lizards are refractory to infection with Borrelia, it appears likely their involvement in the enzootic cycle is more complex and species-specific.While B. burgdorferi is most associated with ticks hosted by white-tailed deer and white-footed mice, Borrelia afzelii is most frequently detected in rodent-feeding vector ticks, and Borrelia garinii and Borrelia valaisiana appear to be associated with birds. Both rodents and birds are competent reservoir hosts for B. burgdorferi sensu stricto. The resistance of a genospecies of Lyme disease spirochetes to the bacteriolytic activities of the alternative complement pathway of various host species may determine its reservoir host association.Several similar but apparently distinct conditions may exist, caused by various species or subspecies of Borrelia in North America. A regionally restricted condition that may be related to Borrelia infection is southern tick-associated rash illness (STARI), also known as Masters disease. Amblyomma americanum, known commonly as the lone-star tick, is recognized as the primary vector for STARI. In some parts of the geographical distribution of STARI, Lyme disease is quite rare (e.g., Arkansas), so people in these regions experiencing Lyme-like symptoms—especially if they follow a bite from a lone-star tick—should consider STARI as a possibility. It is generally a milder condition than Lyme and typically responds well to antibiotic treatment.In recent years there have been 5 to 10 cases a year of a disease similar to Lyme occurring in Montana. It occurs primarily in pockets along the Yellowstone River in central Montana.
In case of failure, guidelines recommend retreatment with injectable ceftriaxone. Several months after treatment for Lyme arthritis, if joint swelling persists or returns, a second round of antibiotics may be considered; intravenous antibiotics are preferred for retreatment in case of poor response to oral antibiotics. Outside of that, a prolonged antibiotic regimen lasting more than 28 days is not recommended as no evidence shows it to be effective. IgM and IgG antibody levels may be elevated for years even after successful treatment with antibiotics. As antibody levels are not indicative of treatment success, testing for them is not recommended.Facial palsy may resolve without treatment; however, antibiotic treatment is recommended to stop other Lyme complications. Corticosteroids are not recommended when facial palsy is caused by Lyme disease. In those with facial palsy, frequent use of artificial tears while awake is recommended, along with ointment and a patch or taping the eye closed when sleeping.About a third of people with Lyme carditis need a temporary pacemaker until their heart conduction abnormality resolves, and 21% need to be hospitalized. Lyme carditis should not be treated with corticosteroids.People with Lyme arthritis should limit their level of physical activity to avoid damaging affected joints, and in case of limping should use crutches. Pain associated with Lyme disease may be treated with nonsteroidal anti-inflammatory drugs (NSAIDs). Corticosteroid joint injections are not recommended for Lyme arthritis that is being treated with antibiotics.