Search

We report an outbreak of equine piroplasmosis in southern Texas, USA, in 2009. Infection prevalence reached 100% in some areas (292 infected horses). Amblyomma cajennense was the predominant tick and experimentally transmitted Theileria equi to an uninfected horse. We suggest that transmission by this tick species played a role in this outbreak. [ABSTRACT FROM AUTHOR]

We report 28 species of ticks (Acari: Ixodida) from Colorado (CO). We include the soft ticks (Argasidae) Argas (Argas) cooleyi Kohls and Hoogstraal, Argas (Persicargas) radiatus Railliet, Carios (Alectorobius) concanensis (Cooley and Kohls), Carios (Alectorobius) kelleyi (Cooley and Kohls), Ornithodoros (Pavlovskyella) hermsi Wheeler et al., Ornithodoros (Pavlovskyella) parkeri Cooley, Ornithodoros (Pavlovskyella) turicata (Dugès), Otobius (Otobius) lagophilus Cooley and Kohls, and Otobius (Otobius) megnini (Dugès). We include the metastriate hard ticks (Ixodidae) Dermacentor (Americentor) albipictus (Packard), Dermacentor (Dermacentor) andersoni Stiles, Dermacentor (Dermacentor) parumapertus Neumann, Dermacentor (Dermacentor) variabilis (Say), Haemaphysalis (Aboimisalis) chordeilis (Packard), Haemaphysalis (Gonixodes) leporispalustris (Packard), and Rhipicephalus (Rhipicephalus) sanguineus Latreille. Prostriate hard ticks include Ixodes (Ixodiopsis) angustus Neumann, Ixodes (Phoeloioxdes) baergi Cooley and Kohls, Ixodes (Trichotoixodes) brunneus Koch, Ixodes (Scaphixodes) howelli Cooley and Kohls, Ixodes (Phoeloioxdes) kingi Bishopp, Ixodes (Phoeloioxdes) marmotae Cooley and Kohls, Ixodes (Ixodiopsis) ochotonae Gregson, Ixodes (Phoeloioxdes) sculptus Neumann, Ixodes (Ixodiopsis) soricis Gregson, Ixodes (Ixodes) spinipalpis Hadwen and Nuttall, Ixodes (Phoeloioxdes) texanus Banks, and Ixodes (Ixodiopsis) woodi Bishopp. Argas radiatus and Ixodes brunneus represent new state records. Review of collection reports revealed that inclusion of Ixodes (Multidentatus) auritulus (Neumann), Ixodes (Phoeloioxdes) cookei Packard, Ixodes (Phoeloioxdes) marxi Banks, and Ixodes (Ixodes) pacificus Cooley and Kohls is dubious or unconfirmed and, conversely, that C. concanensis and H. chordeilis have distributions that include CO. We list an additional five species occasionally detected and 13 exotic species intercepted in CO. Tick-host associations, geographical distributions, and medical/veterinary importance are included., (© The Author(s) 2020. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Phoretic deutonymphs (hypopi) of Schwiebea sp. mites were detected during examinations of questing adult and nymphal blacklegged ticks, Ixodes scapularis Say, from vegetation at two woodland sites in northeastern Wisconsin, USA, during May and June, 2014. Collection sites were in Marinette and Oconto Counties, respectively. These hypopi are evidently the first reported from ticks in the Western Hemisphere, and they seem to be most similar morphologically to the putatively Holarctic species Schwiebea nova (Oudemans)., (Published by Oxford University Press on behalf of Entomological Society of America 2015. This work is written by US Government employees and is in the public domain in the US.)

New distribution records for the Neotropical tick, Amblyomma triste Koch, are identified from 27 specimens in 18 separate collections. These collections originated from six now recognized geographical foci in two states in the United States (Cochise and Santa Cruz Counties, Arizona, and Brewster and Jeff Davis Counties, Texas) and from import cattle, Bos taurus L., presented for entry at the United States border and originating in three Mexican states (Coahuila, Durango, and Sonora). For at least 67 yr, A. triste has existed in some areas of the United States as a cryptic species, and specimens there have been confused with and identified as Gulf Coast ticks, Amblyomma maculatum Koch, even by noted tick specialists. Most of the records reported in this study were from reidentified, archived specimens of putative A. maculatum.

Soft ticks are medically important ectoparasites of birds and mammals that are found throughout the world. This report describes isolation and partial characterization of two embryonic cell lines, CCE2 and CCE3, from the seabird soft tick Carios capensis (Neumann). Sequencing of the mitochondrial 16S rRNA gene and karyology confirmed the lines were derived from C. capensis. CCE3 cells were diploid with a modal chromosome number of 20. The population doubling time for cell lines CCE2 and 3 in passage 40 was 6-9 d. A rickettsial endosymbiont, RCCE3, was co-isolated along with line CCE3. Nucleotide sequences of polymerase chain reaction (PCR) products generated using primers specific for rickettsial 17-kDa antigen, outer membrane protein (omp) A, ompB, and citrate synthase genes along with phylogenetic analyses demonstrated that RCCE3 is a previously uncultured endosymbiont. The rickettsia was identified as a symbiont of C. capensis, closely related to rickettsiae previously detected by PCR in C. capensis, Ornithodoros moubata (Murray) and Hemaphysalis sulcata Canestrini & Fanzago, a hard tick. RCCE3 caused a cytopathic effect in C. capensis host cells, and it was transferred to Ixodes scapularis Say cell line ISE6 for maintenance. The rickettsial endosymbiont was eliminated from CCE3 by treatment with oxytetracycline. Cell lines from C. capensis will be useful to researchers investigating interactions between soft ticks and microorganisms, soft tick physiology, and molecular biology. The rickettsia adds to the growing number of Rickettsia species that have been isolated in tick cell culture, and it is available for characterization.

Seabird soft ticks, Carios capensis (Ixodida: Argasidae), originally collected from coastal Georgia, USA, were allowed to ingest a blood meal from pekin ducklings (Anas domesticus) infected with WNV. After 35 days of extrinsic incubation, the ticks transmitted virus to naive ducklings. WNV was detected via plaque assay and RTPCR in ticks and in tissues and serum of ducklings 7 days post infestation.

Two previously reported PCR methods were evaluated to determine whether they are as sensitive and specific as conventional culture methods in detecting Salmonella spp. from feces. Bovine and equine feces were enriched overnight in brain heart infusion broth and assayed using PCR methods and primer sets described by other investigators. A total of 774 fecal specimens were tested using a primer set (invE-A primer set) that amplifies a region spanning the invasin E and A genes of Salmonella enterica serovar Typhimurium. A subset of these fecal specimens (306 of the 774 total) were tested using primers (hisJ primer set) that amplify a portion of the histidine transport J gene. The PCR required 24 h to obtain results, whereas it took 5 to 7 days to identify Salmonella spp. by culture. PCR detection of Salmonella spp. using the hisJ primers and the invE-A primers had a sensitivity of 93.3 and 80%, respectively, and a specificity of 85.6 and 98.6%, respectively, compared with bacterial culture. Amplification of 42 culture-negative fecal specimens (of 306 total specimens) generated a DNA fragment that corresponded to the molecular weight of the amplified hisJ gene. The hisJ-generated amplicons from six culture-negative and six culture-positive specimens were sequenced and analyzed using DNA sequence alignment and phylogenetic analysis software. A neighbor-joining dendrogram of the DNA sequences of both sets of hisJ amplicons revealed two distinct groups-one group of amplicons from culture-positive specimens identical to the hisJ gene of S. enterica serovar Typhimurium and a second group of amplicons from culture-negative specimens that were more closely related to hisJ of S. enterica serovar Typhimurium than to other hisJ sequences present in nucleotide databases.

Results of a survey for ixodid ticks and/or serum antibodies to Borrelia burgdorferi from 14 species of small to large mammals from eastern coastal areas of the United States are presented. Most samples were obtained from July 1987 through June 1989 (excluding December-March) at 3 locales: Assateague Is. National Seashore, Worcester Co., MD., and Accomack Co., VA. (approximately 38 degrees 05' N 75 degrees 10' W), and Cape Hatteras National Seashore, Dare Co., NC (approximately 35 degrees 30' N 76 degrees 35' W). Hosts sampled included opossums (Didelphis virginiana), least shrews (Cryptotis parva), gray foxes (Urocyon cinereoargenteus), red foxes (Vulpes vulpes), raccoons (Procyon lotor), feral cats (Felis sylvestris), feral horses (Equus caballus), sika deer (Cervus nippon), rice rats (Oryzomys palustris), white-footed mice (Peromyscus leucopus), meadow voles (Microtus pennsylvanicus), house mice (Mus musculus), norway rats (Rattus norvegicus) and jumping mice (Zapus hudsonius). An indirect fluorescent antibody test was used for testing sera from opossums, raccoons, and feral cats; enzyme-linked immunosorbent assays were used for sera from foxes, horses, deer, and house and white-footed mice. Antibodies to B. burgdorferi were found in all species tested from each locale. Seasonal data reinforce the contention that P. leucopus is a suitable sentinel species for B. burgdorferi. Ticks on hosts included Ixodes scapularis Say, I. texanus Banks, Dermacentor variabilis (Say), D. albipictus (Packard), and Amblyomma americanum (L.). Males comprised approximately 0-22 and 60-81% of Ixodes sp. and Amblyomma-Dermacentor adults collected from hosts, respectively. All stages of A. americanum, adult D. variabilis, and larval I. scapularis were collected from vegetation. The highest seropositivity rate (67%) was recorded for 45 P. leucopus at Assateague during July, approximately 1 mo. after peak nymphal I. scapularis intensity. Borrelia burgdorferi was isolated from 6 nymphal and 12 female I. scapularis collected from P. leucopus and C. nippon, respectively, on Assateague.

A taxonomic key, based on restriction enzyme analysis of the second internal-transcribed spacer (ITS-2) in the nuclear ribosomal DNA gene, was developed for identification of 17 Ixodes tick species in the United States. This key includes: Ixodes affinis Neumann, Ixodes angustus Neumann, Ixodes baergi Cooley and Kohls, Ixodes brunneus Koch, Ixodes cookei Packard, Ixodes dentatus Marx, Ixodes jellisoni Cooley and Kohls, Ixodes kingi Bishopp, Ixodes minor Neumann, Ixodes muris Bishopp and Smith, Ixodes pacificus Cooley and Kohls, Ixodes scapularis Say, Ixodes sculpularis Neumann, I. spinipalpis Hadwen and Nuttall, Ixodes texanus Banks, Ixodes uriae White, and Ixodes woodi Bishopp. A 900-bp fragment of the ITS-2 was amplified using the polymerase chain reaction. This fragment was then digested with the restriction enzymes MspI and CfoI, and the digested fragments were size fractionated on a 2.5% high-resolution agarose gel. A dichotomous key was developed based on digested fragment sizes relative to a standard set of size markers. Little intraspecific variation in restriction fragment banding patterns was detected.

Serum samples, collected from Peromyscus leucopus (white-footed mouse) or Peromyscus gossypinus (cotton mouse) during 1987 through 1990 in Florida, Georgia, Maryland, Mississippi, and North Carolina (USA), and in 1997 in southern Connecticut were analyzed by indirect fluorescent antibody (IFA) staining methods or Western blot procedures for antibodies to granulocytic ehrlichiae. Of the 82 sera from white-footed mice in Connecticut tested by IFA methods with either the BDS or NCH-1 strain of the human granulocytic ehrlichiosis (HGE) agent, 45 (55%) and 42 (51%) of the samples contained antibodies to these strains, respectively, at concentrations ranging from 1:80 to 1:2560. One (2%) of 43 sera from P. leucopus captured in Assateague Island (Maryland) had a titer of 1:80, while three (20%) of 15 sera from P. gossypinus, captured in Sapelo Island (Georgia) and four (40%) of 10 sera from cotton mice caught in Amelia Island (Florida) had antibodies to the NCH-1 strain at titers of 1:160 to 1:1,280. Fifty-five sera from P. leucopus in Cape Hatteras (North Carolina) and 30 sera from P. gossypinus in Mississippi were negative. Western blot analyses confirmed seropositivity for 19 (95%) of 20 mouse sera positive by IFA staining methods, including samples from both mouse species captured in Connecticut, Maryland, or Florida. There were key banding patterns to proteins having molecular masses of about 44, 80, 105, 110, or 120 kDa. Both serologic assays can be used to determine if mice have been exposed to granulocytic ehrlichiae. These rodents also may be useful in surveillance programs to identify endemic sites for HGE and in performing laboratory studies on immune responses to the etiologic agent.

An analysis of fluctuating asymmetry was conducted on populations of the blacklegged tick Ixodes scapularis. The eight groups used in this study consisted of larvae and nymphs and males and females from the states of Minnesota, Massachusetts, Maryland, Missouri, North Carolina and Georgia and the F1 progenies of reciprocal crosses between ticks from Massachusetts and Georgia. Measurements included 16 larval, 19 nymphal, ten female and 12 male bilateral characters. Only five differences between the right and left bilateral characters had normal distributions with means of zero and differences in variances between the groups. These five characters included three setal lengths of the larvae, the spiracular plate length of females and the coxa I internal spur widths of males. Bivariate plots of character size ((R + L)/2) and asymmetry (R-L) showed no correlation. In the spiracular plate lengths of females and one of the setal lengths, ticks from Massachusetts had significantly less within-group variance than all the other groups. The only character in which fluctuating asymmetry was observed was the coxa I internal spur width of males, in which ticks from Minnesota, Missouri and North Carolina had significantly greater variance than the remaining groups; fluctuating asymmetry in this character may be explained by sexual selection. The cross progeny did not demonstrate any fluctuating asymmetry, as would be expected if the northern and southern forms of I. scapularis were true species. The virtual lack of fluctuating asymmetry in the characters used in this study further supports the conclusions of other studies which concluded that I. scapularis is a species with clinical variation and a broad geographic distribution.

A morphological study of the larval stage of the blacklegged tick, Ixodes scapularis, was conducted to further examine congruence between northern and southern morphotypes. Preliminary ANOVA revealed that 9 characters were not significantly different; thus 28 characters were used in analyses of a total of 8 groups of I. scapularis originally from Minnesota, Massachusetts, Maryland, Missouri, North Carolina, Georgia, F1 progeny of reciprocal crosses of ticks from Massachusetts and Georgia, and I. pacificus from California. Principal components (PC) analysis identified seven setal (sternal, preanal, 3 scutal, central, and marginal dorsal) and 3 nonsetal characters (interauricular distance, hypostome internal file, and coxa I internal spur) with positive static allometries. All Mahalanobis distances in canonical variate analyses (CVA) including and excluding I. pacificus and setal characters were significantly different. Scatterplots from PC and CVAs separated I. pacificus from all other groups in the first axis; the second function arranged groups in a pattern related to latitude. Unlike the results of previously reported nymphal analyses, no multivariate effect related to longitude was revealed; however, Missouri larvae had the shortest values for 2 setal and 9 nonsetal characters. As in nymphs, frequency polygons revealed an overlapping/continuous pattern, indicative of clinal geographic variation.

The blacklegged tick, Ixodes (Ixodes) scapularis Say, 1821, is redescribed, based on laboratory reared specimens originating in Bulloch County, Georgia. Information on distribution, host associations, morphological variation, and medical/veterinary importance is also presented. A great deal of recent work has focused on this species because it is the principal vector of the agent of Lyme disease (Borrelia burgdorferi Johnson, Schmidt, Hyde, Steigerwaldt & Brenner) in eastern North America. Its distribution appears to be expanding, and includes the state of Florida in the southeastern United States north to the provinces of Nova Scotia and Prince Edward Island, Canada, west to North and South Dakota, United States, and south to the state of Coahuila, Mexico. Although I. scapularis feeds on at least 125 species of North American vertebrates (54 mammalian, 57 avian, and 14 lizard species), analysis of the U.S. National Tick Collection holdings show that white-tailed deer, Odocoileus virginianus (Zimmermann), cattle, Bos taurus L., dogs, Canis lupus L., and other medium-to-large sized mammals are important hosts for adults as are native mice and other small mammals, certain ground-frequenting birds, skinks, and glass lizards for nymphs and larvae. This tick is a polytypic species exhibiting north-south and east-west morphological clines. Analysis of variance and Student-Newman-Keuls multiple comparisons revealed significant interpopulational variation that is expressed most significantly in the nymphal stage. Nymphs from northern (Minnesota, Massachusetts, Maryland) populations had relatively larger basis capituli with shorter cornua (except Maryland) than southern (North Carolina, Georgia) populations. Midwestern populations (Minnesota, Missouri) differed from eastern populations (Massachusetts, Maryland, North Carolina, Georgia) in idiosomal characters (broader scuta, larger coxae III, and IV). In addition to Lyme disease, this tick is also a primary vector of the agent of human and rodent babesiosis, Babesia microti Franca. Under laboratory conditions it has transmitted the agents of deer babesiosis, Babesia odocoilei Emerson & Wright, tularemia, Francisella tularensis McCoy & Chapin, and anaplasmosis, Anaplasma marginale Theiler. Moreover, I. scapularis can reach pest proportions on livestock, and females can cause tick paralysis in dogs.

A morphological study of postlarval stages of the blacklegged tick, Ixodes scapularis Say, was conducted to examine congruence between northern (formerly I. dammini Spielman, Clifford, Piesman & Corwin) and southern morphotypes. The character set totaled 17 for females, 25 for males, and 28 for nymphs. Populations from 6 geographic areas, F1 progeny from reciprocal crosses between I. scapularis from Massachusetts and Georgia, and I. pacificus Cooley & Kohls from California were measured. Characters, except cornua length in nymphs, were positively correlated with PC1, indicating it was a general-size eigenvector. Characters used previously by others to distinguish northern and southern forms had a highly positive allometric relationship to general size. In canonical variate analysis (CVA) of nymphs, canonical score 1 (CAN1) discriminated I. pacificus from all other groups, canonical score 2 (CAN2) discriminated the remaining groups in a pattern that correlated with latitude, and canonical score 3 (CAN3) separated the western (Minnesota and Missouri) from the eastern groups. Size-free CVA indicated that north-south discrimination was size dependent, but that variation between Missouri and all other groups was not size related. Mahalanobis distances between groups within stages were significant with the exception of the 2 groups of female progeny of reciprocal crosses (Massachusetts x Georgia). Analysis of variance and Student-Newman-Keuls tests revealed that each geographic population differed from all other groups in at least 1 nymphal character. Nymphs from northern areas (Minnesota, Massachusetts, Maryland) differed from those from southern areas (Missouri, North Carolina, Georgia) in characters associated with the basis capitulum (longer intercornua and interauricular distances, basis capituli, and hypostome internal files, larger auriculae, but shorter cornua). Western populations (Minnesota, Missouri) differed from eastern populations in idiosomal characters (broader scutum, larger coxae III and IV). Frequency polygons of characters with the greatest differences indicated that data are continuous and geographic variation is overlapping. Thus, the data support the previous contention of conspecificity of I. scapularis and I. dammini. I. scapularis appears to be a polytypic species with a widespread geographic distribution exhibiting north-south and east-west morphological clines in eastern North America.

This is the first report of natural infection by Borrelia burgdorferi in the cotton rat Sigmodon hispidus. Nine B. burgdorferi isolates were obtained from ear tissues, urinary bladders, or both, by culturing tissues in BSKII medium. The rat from which the SI-3 isolate was cultured was from the same site (Sapelo Island, Georgia) as an infected cotton mouse Peromyscus gossypinus and Ixodes scapularis tick reported previously. The 8 B. burgdorferi isolates from rats in Florida included 1 (AI-1) from Amelia Island, 1 (FD-1) from Faver-Dykes State Park, and 6 (MI-3 through MI-8) from Merritt Island. The distance between Sapelo Island and Merritt Island is approximately 400 km. All B. burgdorferi isolates were characterized by indirect immunofluorescence using monoclonal antibodies to OspA (H3TS, H5332) and OspB (H5TS, H6831), polymerase chain reaction detection of specific B. burgdorferi B-31 DNA target sequences (ospA, fla, and a random chromosomal sequence), and sodium dodecyl sulfate-polyacrylamide gel electrophoresis of spirochetal proteins. The phenotypic and genotypic characteristics of the isolates are discussed, as well as the probable importance of the cotton rat as a reservoir for B. burgdorferi in the southern United States.

The isolation of the Lyme disease spirochete (Borrelia burgdorferi) from the southeastern United States is reported. Three isolates, two from cotton mice (Peromyscus gossypinus) and one from the black-legged tick (Ixodes scapularis), were recovered from Sapelo Island, Georgia, in July and September 1991. The spirochetes were characterized by indirect fluorescent antibody assay using a battery of five monoclonal antibodies, by sodium dodecyl sulfate/polyacrylamide gel electrophoresis (SDS/PAGE) of whole cell lysates, and by the polymerase chain reaction (PCR) assay using primers for three DNA target sequences found in B. burgdorferi reference strain B-31. Transmission experiments indicate that the three Georgia isolates can infect experimentally inoculated hamsters and mice. Tick transmission of one of the isolates has been attempted so far; I. scapularis transmitted isolate SI-1 from hamsters to mice, but the lone-star tick, Amblyomma americanum, did not.

Reciprocal crosses between Ixodes dammini Spielman, Clifford, Piesman & Corwin from Massachusetts and Ixodes scapularis Say from Georgia produced offspring through the F3 generation when the experiment was discontinued. Reciprocal I. dammini x Ixodes pacificus Cooley & Kohls (California) and I. scapularis x I. pacificus crosses produced F1 progeny; however, all progeny were sterile. Assortative mating experiments between I. dammini and I. scapularis indicated that males and females of both species mated with the opposite sex of heterospecific or conspecific ticks when there was a choice. Conventional discriminant analysis of morphometric measurements of ticks from Georgia, North Carolina, Maryland, Massachusetts, and two populations of F1 hybrids indicated that there were recognizable differences. However, size-free (sheared) discriminant analysis indicated that these differences were largely size-dependent, with much overlap of the four eastern and two hybrid populations but no overlap with I. pacificus from California. Analysis of chromosomes (morphology and C band) indicated no differences between the Georgia and Massachusetts populations but showed a difference between them and the California population of I. pacificus. Analysis of isozymes showed that the genetic identity value for the Georgia and Massachusetts populations was within the normal range for conspecific populations, whereas the California population indicated congeneric but not conspecific relatedness to the Georgia and Massachusetts populations. Life cycle data collected under similar laboratory conditions showed no differences in length of feeding and molting periods among Georgia, Massachusetts, and California populations. These data and results of the work of other authors on tick host preferences and vector competence indicate that I. dammini is not a valid species separate from I. scapularis. Because the name Ixodes scapularis Say, 1821, has priority over the name Ixodes dammini Spielman, Clifford, Piesman & Corwin, 1979, I. dammini is relegated to a junior subjective synonym of I. scapularis (based on Article 23 of the International Code of Zoological Nomenclature).

Serologic studies were conducted to determine whether white-footed mice (Peromyscus leucopus) and cotton mice (Peromyscus gossypinus) contained serum antibodies to Borrelia burgdorferi, the causative agent of Lyme borreliosis. Enzyme-linked immunosorbent assays detected antibodies to this spirochete in 35.7 and 27.3% of 56 P. leucopus and 535 P. gossypinus serum samples, respectively, collected in Connecticut, North Carolina, South Carolina, Georgia, Florida, Alabama, and Mississippi. Antibody titers ranged from 1:160 to greater than or equal to 1:40,960. On the basis of adsorption tests, the antibodies detected appeared to be specific to Borrelia spirochetes. Seropositive rodents in the eastern and southern United States, areas where human cases of Lyme borreliosis have been reported, indicate a widespread geographic distribution of B. burgdorferi or a closely related spirochete.

Ornithodoros (Alectorobius) capensis Neumann, an ectoparasite of seabirds found circumglobally in the tropics and subtropics, has become established along the southeastern seacoast of the United States. The tick has been found feeding primarily on brown pelicans, Pelecanus occidentalis, but also has been found on the laughing gull, Larus atricilla, and the American oystercatcher, Haematopus palliatus. We report here the presence of O. (A.) capensis from New Hanover and Brunswick counties (near the mouth of the Cape Fear River) in North Carolina, to the Charleston Harbor area of South Carolina and thence south to Cumberland Island (a barrier island) in Camden County, Georgia, just north of the Florida state line.

An enzyme-linked immunosorbent assay (ELISA) was developed to detect serum antibodies to Borrelia burgdorferi, the causative agent of Lyme borreliosis, in deer (Odocoileus virginianus) and raccoons (Procyon lotor). Blood samples were collected from these mammals in Connecticut, Maryland, North Carolina, Georgia and Florida. Seropositivity for deer was highest in Connecticut (56% of 353 sera) and Maryland (51% of 35 sera). Raccoons in Connecticut, Maryland, North Carolina, and Florida also had antibodies to B. burgdorferi, but prevalence of positive sera was highest in Maryland (79% of 14 samples). Based on adsorption tests, the immunoglobulins detected in these mammals were probably specific to B. burgdorferi. The ELISA was more sensitive than an indirect fluorescent antibody staining method and was more suitable for analyzing large numbers of serum samples.

New host and distributional records, seasonal activities in Georgia, laboratory rearing data, and taxonomic description of nymphal and larval Ixodes affinis are presented. Our data expand the list of known natural hosts of this species, record for the first time several natural hosts of larvae and nymphs, provide information on feeding periods of all stages, preecdysial intervals, preovipositional, ovipositional, and incubational periods, as well as provide information on fecundity. The immatures are fully described and SEM micrographs of them are presented.