Coronavirus (COVID-19) updates, visitor restrictions and resources →

Rickettsial pox

  • Definition
    • Rickettsial pox is a disease spread by a mite. It causes a chickenpox-like rash on the body.

  • Causes
    • Rickettsial pox is caused by the bacteria, Rickettsia akari. It is commonly found in the United States in New York City and other city areas. It also has been seen in South Africa, Korea, and Russia.

      The bacteria are spread by the bite of a mite that lives on mice.

  • Symptoms
    • The disease begins at the site of the mite bite as a painless, firm, red lump (nodule). The nodule develops into a fluid-filled blister that bursts and crusts over. This lump may be up to an inch wide.

      Other symptoms include:

      • Discomfort in bright light (photophobia)
      • Fever and chills
      • Muscle pain (myalgia)
      • Rash that looks like chickenpox
      • Sweating

      The rash usually clears within a week.

  • Exams and Tests
    • The health care provider will do an examination to look for a rash similar to the one in chickenpox.

      Tests include:

      • Complete blood count (CBC)
      • Tests of blood serum (serologic studies)
  • Treatment
    • The goal of treatment is to cure the infection by taking antibiotics.

  • Outlook (Prognosis)
    • A full recovery is expected when antibiotics are taken as instructed.

  • Possible Complications
    • There are usually no complications if the infection is treated.

  • When to Contact a Medical Professional
    • Call your health care provider if you or your child has symptoms of rickettsial pox.

  • Prevention
    • Sanitary measures, especially controlling mice and their parasites, will prevent the spread of rickettsial pox.

  • References
    • Raoult D. Rickettsia akari (Rickettsial pox). In: Bennett JE, Dolin R, Mandell GL, eds. Principles and Practice of Infectious Diseases. 8th ed. Philadelphia, PA: Saunders Elsevier; 2014:chap 189.

      Reller ME, Dumler JS. Spotted fever and transitional group rickettsioses. In: Kliegman RM, Stanton BF, St. Geme JW III, et al., eds. Nelson Textbook of Pediatrics. 19th ed. Philadelphia, PA: Saunders Elsevier; 2011:chap 220.