TY - JOUR
T1 - Human Seroprevalence of Tick-Borne Anaplasma phagocytophilum, Borrelia burgdorferi, and Rickettsia Species in Northern California
AU - Pascoe, Emily L.
AU - Stephenson, Nicole
AU - Abigana, Ashley
AU - Clifford, Deana
AU - Gabriel, Mourad
AU - Wengert, Greta
AU - Brown, Richard
AU - Higley, Mark
AU - Bloch, Evan M.
AU - Foley, Janet E.
N1 - Funding Information:
We thank the UC Davis student chapter of the Humane Society Veterinary Medical Association, Michael Clifford, undergraduate volunteers of the Foley laboratory, the Humboldt State student chapter of the western section of The Wildlife Society, the Greater Rural Rescue Society, the Hoopa Valley Tribe, Aaron Pole, Deborah Giraud, Anne Kjemtrup, Jennifer McQuiston, and Kerry Padgett. JEF and ELP acknowledge funding from the Pacific Southwest Regional Center of Excellence for Vector-Borne Diseases funded by the U.S. Centers for Disease Control and Prevention (Cooperative Agreement 1U01CK000516) and the UC Davis School of Veterinary Medicine. This study was also supported by the UC Davis Center for Companion Animal Health, John Muir Institute for the Environment, the Center for Vector-borne Diseases, and LymeDisease.org.
Publisher Copyright:
© Copyright 2019, Mary Ann Liebert, Inc., publishers 2019.
PY - 2019/12
Y1 - 2019/12
N2 - There is a paucity of data on human exposure to tick-borne pathogens in the western United States. This study reports prevalence of antibodies against three clinically important tick-borne pathogens (Borrelia burgdorferi, Anaplasma phagocytophilum, and Rickettsia spp.) among 249 people in five counties in northern California. Individuals from Humboldt County were recruited and answered a questionnaire to assess risk of exposure to tick-borne pathogens. Samples from other counties were obtained from a blood bank and were anonymized. Seventeen (6.8%) samples were seropositive for antibodies against at least one pathogen: five for A. phagocytophilum, eight for B. burgdorferi, and four for Rickettsia spp. Women and people aged 26-35 had higher seroprevalence compared to other demographic groups. Santa Cruz County had no seropositive individuals, northern Central Valley counties had three seropositive individuals (all against A. phagocytophilum), and Humboldt County had 14 (all three pathogens), a significant, four-fold elevated risk of exposure. The Humboldt County questionnaire revealed that a bird feeder in the yard was statistically associated with exposure to ticks, and lifetime number of tick bites was associated with increasing age, time watching wildlife, and time hiking. Three-quarters of respondents were concerned about tick-associated disease, 81.0% reported experiencing tick bites, and 39.0% of those bitten reported a tick-borne disease symptom, including skin lesions (76.4%), muscle aches (49.1%), joint pain (25.5%), or fever (23.6%). Despite high levels of concern, many individuals who had been bitten by a tick were not tested for a tick-borne pathogen, including those with consistent symptoms. We highlight the need for further research and dissemination of information to residents and physicians in Northern California regarding tick-associated disease, so that appropriate medical attention can be rapidly sought and administered.
AB - There is a paucity of data on human exposure to tick-borne pathogens in the western United States. This study reports prevalence of antibodies against three clinically important tick-borne pathogens (Borrelia burgdorferi, Anaplasma phagocytophilum, and Rickettsia spp.) among 249 people in five counties in northern California. Individuals from Humboldt County were recruited and answered a questionnaire to assess risk of exposure to tick-borne pathogens. Samples from other counties were obtained from a blood bank and were anonymized. Seventeen (6.8%) samples were seropositive for antibodies against at least one pathogen: five for A. phagocytophilum, eight for B. burgdorferi, and four for Rickettsia spp. Women and people aged 26-35 had higher seroprevalence compared to other demographic groups. Santa Cruz County had no seropositive individuals, northern Central Valley counties had three seropositive individuals (all against A. phagocytophilum), and Humboldt County had 14 (all three pathogens), a significant, four-fold elevated risk of exposure. The Humboldt County questionnaire revealed that a bird feeder in the yard was statistically associated with exposure to ticks, and lifetime number of tick bites was associated with increasing age, time watching wildlife, and time hiking. Three-quarters of respondents were concerned about tick-associated disease, 81.0% reported experiencing tick bites, and 39.0% of those bitten reported a tick-borne disease symptom, including skin lesions (76.4%), muscle aches (49.1%), joint pain (25.5%), or fever (23.6%). Despite high levels of concern, many individuals who had been bitten by a tick were not tested for a tick-borne pathogen, including those with consistent symptoms. We highlight the need for further research and dissemination of information to residents and physicians in Northern California regarding tick-associated disease, so that appropriate medical attention can be rapidly sought and administered.
KW - Anaplasma phagocytophilum
KW - Borrelia burgdorferi
KW - Lyme borreliosis
KW - Rickettsia rickettsii
KW - Rocky Mountain spotted fever
KW - anaplasmosis
UR - http://www.scopus.com/inward/record.url?scp=85075960390&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85075960390&partnerID=8YFLogxK
U2 - 10.1089/vbz.2019.2489
DO - 10.1089/vbz.2019.2489
M3 - Article
C2 - 31295054
AN - SCOPUS:85075960390
SN - 1530-3667
VL - 19
SP - 871
EP - 878
JO - Vector-Borne and Zoonotic Diseases
JF - Vector-Borne and Zoonotic Diseases
IS - 12
ER -