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Babesiosis risk factors

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]Associate Editor(s)-in-Chief: Ilan Dock, B.S.

Overview

Overview

Babesiosis may be transmitted/contracted during all months of the year. However there is correlation between heightened rates of patient infection, spring, and the summer.

The most potent risk factors in the development of Babesiosis are a combined effort between environment and season. Babesia parasites are transmitted via tick bites in tick-populated areas. Transmission occurs more frequently during the spring and summer in correlation with heightened periods of tick activity. Other risk factors include repeated exposure to the following potential I. scapularis and Ixodes rodent hosts; white-footed deer mice, rats, voles, chipmunks, and field mice.[1][2]


Further examples of Babesia mammalian hosts also include deer populations. Although unlike the rodent transmission, transmission of Babesia from deer to human populations is likely a result of an infected nymph bite. Reduction tactics therefore include reduced contact and increased proximity from rodent, deer, and tick populations in endemic areas.

Another risk factor, though rare, may be attributed to the transmission of Babesiosis via blood transfusion. In certain cases, Babesiosis is asymptomatic and contaminated blood may inadvertently be drawn from donors within endemic areas. Furthermore case reports also indicate rare occurrences of transmission via transplacental and perinatal pathways. [3]

Age may be an associated risk factor as well. A recent study performed by the Central for Disease Control and Prevention (CDC), identifies 62 years as the median age of reported babesiosis cases in the United States.[1]


Furthermore the study incorporated patients with ages ranging from infantry (less than a year) to individuals of over 100 years. Of the observed cases, 65% were documented as males and 32% as female. However no further determinations were provided about the correlations between age, sex and a heightened risk of contracting the disease.[1]


Common risk factors

Common risk factors

  • Being bitten by an infected tick
  • Residing in an endemic area, primarily the Northeastern, United States coast
  • Repeated exposure to common I. scapularis and Ixodes hosts; white-footed deer mice, rats, voles, chipmunks, and field mice
  • Outdoor recreational activity during seasons of high tick activity
Less common risk factors

Less common risk factors

  • Patients with a medical history including a splenectomy or any immunocompromising diseases
  • Receiving a blood transfusion from a donor residing in an endemic area
  • Elderly individuals are more susceptible to infection (Most cases occur within patients of 50 to 60 years)


References

References

  1. 1.0 1.1 1.2 Babesiosis Epidemiology. Center for Disease Control and Prevention (2015). http://www.cdc.gov/parasites/babesiosis/data-statistics/index.html. Accessed December 8, 2015.
  2. Babesiosis Disease. For Health Professionals. Center for Disease Control and Prevention(2015). http://www.cdc.gov/parasites/babesiosis/disease.htmlAccessed December 8, 2015.
  3. Babesiosis. For Health Professionals. Centers for Disease Control and Prevention (2015). http://www.cdc.gov/parasites/babesiosis/health_professionals/index.html Accessed on December 08, 2015

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