An infectious disease transmitted by a mite and characterized by a "chickenpox-like" rash .

Causes, incidence, and risk factors

Rickettsialpox is caused by Rickettsia akari , and it is commonly found ( endemic ) in the United States in New York City and other urban areas. It also has been recognized in South Africa, Korea, and Russia. It is transmitted by the bite of a mite which lives on mice ( Liponyssoides sanguineus ). The disease begins at the site of the mite bite as a non-tender, firm, red nodule that develops into a vesicle (fluid-filled blister ) which then bursts and crusts over. This lesion may be large -- almost up to an inch across. Several days later, the patient develops a fever and chills with sweating (diaphoresis), and muscle pain (myalgia). Over the next 2 to 3 days, a rash develops with many small versions of the initial lesion which resemble the chickenpox rash. These lesions clear up within a week.

Signs and tests

Physical examination confirms the presence of a rash that resembles chicken pox . Tests include:

Treatment

Expectations (prognosis)

Full recovery is expected.

Complications

There are usually no complications if the disorder is treated.

Calling your health care provider

Call your health care provider if your child has symptoms suggestive of rickettsial pox.

Prevention

Sanitary measures, especially with regard to control of mice and their parasites, will prevent spread of rickettsialpox.