Comparing Contributions of Passive and Active Tick Collection Methods to Determine Establishment of Ticks of Public Health Concern Within Illinois

Abstract

In Illinois, between 1990 and 2017, tick-borne diseases in humans increased 10-fold, yet we have insufficient information on when and where people are exposed to vector ticks (Ixodida: Ixodidae). The aims of our research were to compare contributions of passive and active tick collection methods in determining establishment of ticks of public health concern and obtain information on tick distributions within Illinois. We used three surveillance strategies within the Illinois Tick Inventory Collaboration Network to gather information about the ticks of public health concern: 1) passive collection (voluntary submission by the public); 2) systematic collection (biweekly active surveillance); and 3) special collections (active collections in locations of special interest). Of collected adult and nymphal ticks, 436 were from passive collections, 142 from systematic collections, and 1,270 from special collections. Tick species distribution status changed in 36 counties. Our data provide noteworthy updates to distribution maps for use by public health agencies to develop prevention and control strategies. Additionally, the program built a network of collaborations and partnerships to support future tick surveillance efforts within Illinois and highlighted how the combination of the three surveillance strategies can be used to determine geographic spread of ticks, pinpoint locations in need of more surveillance, and help with long-term efforts that support phenology studies.

Effects of Climate on the Variation in Abundance of Three Tick Species in Illinois

“…Between May 2018 and November of 2019, ticks were collected via dragging eventsat sites in 24 central and 24 southern Illinois counties ( Fig. 1 ; Table 1 ; Supp Table 1 [online only ]) in the study area ( Lyons et al 2021 ). Researchers dragged 1 m 2 white canvas flags with trailing ‘fingers’ along both sides of three established transects of 100 m, for a total of 600 m 2 dragged per site, per visit ( Lyons et al 2021 ).…”

“…1 ; Table 1 ; Supp Table 1 [online only ]) in the study area ( Lyons et al 2021 ). Researchers dragged 1 m 2 white canvas flags with trailing ‘fingers’ along both sides of three established transects of 100 m, for a total of 600 m 2 dragged per site, per visit ( Lyons et al 2021 ). Every 10–15 m, researchers stopped to check the drag cloth for any ticks.…”

Monitoring Trends in Distribution and Seasonality of Medically Important Ticks in North America Using Online Crowdsourced Records from iNaturalist

“…Most of the iNaturalist observations were adult specimens, presumably because these are easier to detect and photograph, and this passive surveillance method is therefore less effective at collecting information on immature tick stages. As a result, the seasonal observations of ticks gained from iNaturalist data describe the documented phenology of the adult stages of tick species in North America [ 1 , 22 , 34 , 40 , 41 , 49 , 50 , 51 , 77 , 78 ]. This will have implications for the suitability of tick occurrence data from iNaturalist in informing the risk from diseases that are epidemiologically linked to nymphal stages of ticks.…”

“…Passive surveillance systems, in which tick specimens found on humans and animals are submitted to researchers by members of the public or veterinary and medical practices, have contributed significantly to knowledge of tick distribution, seasonal activity, host associations, and pathogen infection prevalence in North America, and can act as early warning systems for the introduction, establishment, and expansion of species of public health or veterinary concern [ 19 , 24 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 ]. Results from passive tick surveillance have been demonstrated to correlate well with the distribution of tick-borne diseases [ 7 , 29 , 45 , 52 , 53 , 54 ] and tick abundance from active surveillance [ 55 ].…”

Northward Expansion ofAmblyomma americanum(Acari: Ixodidae) into Southern Michigan

“…Recently, breeding populations of A. americanum have been documented in southern New England (Stafford et al 2018, Telford et al 2019) and in states surrounding the Great Lakes, established populations of have been spreading northwards in Illinois (Gilliam et al 2020, Lyons et al 2021), Indiana (Wojan et al 2021), and Ohio (Fitak et al 2014). Although there have been increases in A. americanum detected by the public in Wisconsin (Christenson et al 2017) and southern Ontario (Nelder et al 2019), established populations have not yet been declared in those areas (at the time of manuscript submission).…”