Why Lyme disease is common in the northern US, but rare in the south: The roles of host choice, host-seeking behavior, and tick density
- DOI
- Language of the publication
- English
- Date
- 2021-01-28
- Type
- Article
- Author(s)
- Ginsberg, Howard S.
- Hickling, Graham J.
- Burke, Russell L.
- Ogden, Nicholas H.
- Beati, Lorenza
- LeBrun, Roger A.
- Arsnoe, Isis M.
- Gerhold, Richard
- Han, Seungeun
- Jackson, Kaetlyn
- Maestas, Lauren
- Moody, Teresa
- Pang, Genevieve
- Ross, Breann
- Rulison, Eric L.
- Tsao, Jean I.
- Publisher
- PLOS
Abstract
Lyme disease is common in the northeastern United States, but rare in the southeast, even though the tick vector is found in both regions. Infection prevalence of Lyme spirochetes in host-seeking ticks, an important component to the risk of Lyme disease, is also high in the northeast and northern midwest, but declines sharply in the south. As ticks must acquire Lyme spirochetes from infected vertebrate hosts, the role of wildlife species composition on Lyme disease risk has been a topic of lively academic discussion. We compared tick–vertebrate host interactions using standardized sampling methods among 8 sites scattered throughout the eastern US. Geographical trends in diversity of tick hosts are gradual and do not match the sharp decline in prevalence at southern sites, but tick–host associations show a clear shift from mammals in the north to reptiles in the south. Tick infection prevalence declines north to south largely because of high tick infestation of efficient spirochete reservoir hosts (rodents and shrews) in the north but not in the south. Minimal infestation of small mammals in the south results from strong selective attachment to lizards such as skinks (which are inefficient reservoirs for Lyme spirochetes) in the southern states. Selective host choice, along with latitudinal differences in tick host-seeking behavior and variations in tick densities, explains the geographic pattern of Lyme disease in the eastern US.
Plain language summary
Infection prevalence of Lyme spirochetes in host-seeking ticks, an important component to the risk of Lyme disease, is also high in the northeast and northern midwest, but declines sharply in the south. As ticks must acquire Lyme spirochetes from infected vertebrate hosts, the role of wildlife species composition on Lyme disease risk has been a topic of lively academic discussion. We compared tick–vertebrate host interactions using standardized sampling methods among 8 sites scattered throughout the eastern US. Geographical trends in diversity of tick hosts are gradual and do not match the sharp decline in prevalence at southern sites, but tick–host associations show a clear shift from mammals in the north to reptiles in the south. Tick infection prevalence declines north to south largely because of high tick infestation of efficient spirochete reservoir hosts (rodents and shrews) in the north but not in the south. Minimal infestation of small mammals in the south results from strong selective attachment to lizards such as skinks in the southern states. Selective host choice, along with latitudinal differences in tick host-seeking behavior and variations in tick densities, explains the geographic pattern of Lyme disease in the eastern US.
Subject
- Health
Keywords
- Animals,
- Animals, Wild,
- Borrelia burgdorferi / physiology,
- Climate,
- Disease Reservoirs / microbiology,
- Disease Reservoirs / statistics & numerical data,
- Disease Vectors* / classification,
- Geography,
- Host Specificity / physiology,
- Host-Seeking Behavior / physiology*,
- Humans,
- Lizards / microbiology,
- Lyme Disease / epidemiology*,
- Lyme Disease / transmission,
- Mice,
- Population Density,
- Prevalence,
- Rats,
- Sciuridae / microbiology,
- Shrews / microbiology,
- Tick Infestations / epidemiology,
- Tick Infestations / microbiology,
- Tick Infestations / transmission,
- Ticks / microbiology,
- United States / epidemiology
Rights
Pagination
1-20
Peer review
Yes
Open access level
Gold
Identifiers
- Government document number
- 33507921
- ISSN
- 1545-7885
Article
- Journal title
- PLOS Biology
- Journal volume
- 19
- Journal issue
- 9
- Article number
- e3001396