The Traveller in Tick Friendly Environments

The number of reported cases of Rocky Mountain Spotted Fever (RMSF) in the United States has tripled since 2010. While the disease is mostly found in 8 states (Oklahoma, Tennessee, Arkansas, Maryland, Virginia and North and South Carolina), it is generally accepted that it might be found in any State.

Reports of RMSF in California

Two reports of RMSF like disease have recently been reported in Northern California. While the cases cannot be viewed as “classical RMSF” they can still be attributed to rickettsial disease transmitted by a tick. Neither had evidence of a typical tick bite lesion but both had symptoms consistent with rickettsial disease. Both cases required intensive care in hospital.

Spotted Fever Group rickettsial disease is notifiable in California but very few cases are reported annually.

The 2 cases are a good reminder of the need to reduce tick exposure when undertaking activities in “tick friendly” environments at certain times of the year. The first case involved a golfer whose activities were close to a national park. He needed to enter vegetation to retrieve his golf balls. In the second case, the individual had been camping. He had remembered seeing a tick on his body but couldn’t remember a tick bite.

TICK-BORNE DISEASES GLOBALLY

Ticks are found worldwide. More than 900 species have been identified. Less than 30 are known to transmit disease to humans. They mostly feed on wild animals. Humans are accidental hosts when they trespass into their environment.