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Disease caused by parasites belonging to the genus Plasmodium

  • Incubation: period varies from 12 to 30 days depending on the species of plasmodium responsible for the infection. Plasmodium vivax is the most prevalent and typically takes about 14 days.
  • Symptoms: Typical symptoms are violent fever lasting six to eight hours that recur every two to three days (chills and fever cycles). Severe chills and shivering lasting approximately an hour, followed by high fever for one to two hours more. Left untreated anemia and enlargement of the spleen develop.
  • Diagnosis: with blood test by physician.
  • Treatment: with anti-malaria drugs.

Known Occurrences in Napa County

No locally contracted cases of malaria have occurred in Napa County in more than 65 years. The last imported cases occurred in 2006 (3 individuals).