Babesia microti


Published on

Published in: Health & Medicine, Technology
  • Be the first to comment

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide
  • Prevalence?
  • Size range?
  • Upset stomach, diarrhea, vomiting, skin rash, etc.
  • Babesia microti

    1. 1. Babesia microti By Raz S. Abdulla 2 nd stage Bio dep. 2010-2011
    2. 2. Outline… <ul><li>Taxonomy </li></ul><ul><li>Babesiosis </li></ul><ul><li>Morphology </li></ul><ul><li>Geographic Distribution </li></ul><ul><li>Hosts </li></ul><ul><li>Life Cycle </li></ul><ul><li>Pathogenesis/Clinical Signs & Symptoms </li></ul><ul><li>Diagnosis </li></ul><ul><li>Treatment </li></ul><ul><li>References </li></ul>
    3. 3. Taxonomy <ul><li>Kingdom: Protista </li></ul><ul><li>Phylum: Apicomplexa </li></ul><ul><li>Class: Aconidasida </li></ul><ul><li>Order: Piroplasmida </li></ul><ul><li>Family: Babesiidae </li></ul><ul><li>Babesia microti </li></ul>
    4. 4. Babesiosis <ul><li>Prior to 1969 Babesia infections were rare and limited to B. divergens (a cattle parasite) and some others species that were parasitic in rodents. </li></ul><ul><li>It was only seen in splenectomized patients who had disabled immune systems as a result of the splenectomy. </li></ul><ul><li>1969, Nantucket Island, Mass: 1 st human Babesia infection in a non-splenectomized patient. </li></ul><ul><li>Hundreds of cases have been reported since. </li></ul>
    5. 5. Morphology <ul><li>Easily misdiagnosed as Plasmodium in areas high in Malaria prevalence due to its “ring shape” </li></ul><ul><li>Variation in shape and size </li></ul><ul><li>Do not produce pigment </li></ul>Intraerythrocytic Babesia microti
    6. 6. Geographic Distribution <ul><li>Worldwide </li></ul><ul><ul><li>Europe: B. divergens , most common </li></ul></ul><ul><ul><li>United States: B. microti , most common in NE and MW portions </li></ul></ul><ul><ul><ul><li>WA-1 strain recently found on west coast </li></ul></ul></ul><ul><ul><li>* May not be as prevalent in malaria-endemic countries* </li></ul></ul>
    7. 7. Hosts <ul><li>Definitive host: Humans or Deer tick </li></ul><ul><li>Vector: Ixodes scapularis (Deer tick) </li></ul><ul><li>Intermediate host: White-footed mouse and other rodents and Deer </li></ul><ul><ul><li>When the deer or mouse pop. increases, the tick pop. does too. </li></ul></ul>
    8. 8. Life Cycle <ul><ul><li>Babesia infected tick introduces sporozoites into the mouse host. </li></ul></ul><ul><ul><li>Sporozoites enter erythrocytes and undergo asexual reproduction (budding). </li></ul></ul><ul><ul><li>In the blood, parasites undergo male and female differentiation (micro- and macrogametes are formed). </li></ul></ul><ul><ul><li>The deer tick (definitive host) takes a blood meal ingesting gametes, which can now undergo fertilization within the gut, 5. resulting in sporozoite formation. Spread to salivary glands. </li></ul></ul>
    9. 9. Life Cycle Cont’d… <ul><li>6. During a blood meal, the tick infects the human host. Inoculation occurs by a tick larva, nymph or adult. </li></ul><ul><li>Sporozoites invade erythrocytes and a trophozoite differentiates, replicating asexually by budding: responsible for the </li></ul><ul><li>clinical manifestations. This </li></ul><ul><li>forms 2-4 merozoites which </li></ul><ul><li>eventually reinvade other RBCs. </li></ul><ul><li>Humans are for all practical purposes “dead-end” hosts, because subsequent transmission after the tick feeds on a human is unlikely. Human to human transmission is well recognized to occur through blood transfusions. Babesia can be transmitted in utero. </li></ul>
    10. 11. Pathogenesis (Signs & Symptoms) <ul><li>1-4 weeks (can last several weeks): fever, chills, headache, nausea, vomiting, and/or muscle aches (myalgia), hemolytic anemia, jaundice and splenomegaly. </li></ul><ul><li>May be mild in otherwise healthy people </li></ul><ul><li>May be asymptomatic </li></ul><ul><li>Severe form of Babesiosis may be life-threatening if untreated (usually people who have been splenectomized, the elderly, or who have impaired immune systems). </li></ul>
    11. 12. Diagnosis <ul><li>Microscopic examination: thick and thin blood smears stained with Giesma </li></ul><ul><li>Antibody detection: detects even low levels of parasitic invasion </li></ul><ul><ul><li>Indirect fluorescent antibody test (IFA) detects antibodies (IgM & IgG) of patients with B. microti infection </li></ul></ul><ul><ul><li>Recommended only if low levels of parasitemia or blood smear is inconclusive </li></ul></ul><ul><li>Diagnosis can be derived from molecular techniques, such as PCR </li></ul><ul><ul><li>Valuable in investigations of new Babesia species </li></ul></ul>
    12. 13. Treatment <ul><li>Clindamycin*: antibiotic with little or no side effects </li></ul><ul><li>Quinine or Atovaquone*: antiparasitic </li></ul><ul><li>Azithromycin*: antibiotic, some side effects </li></ul><ul><li>Clindamycin combined with Quinine is treatment of choice </li></ul><ul><li>* FDA approved, but considered investigational </li></ul>
    13. 14. <ul><li> </li></ul>ReferenceS