Biomedical subjects

J H Oliver

Publications and source records attributed to J H Oliver.

At least 19 recordsLinked to original sources

PubMed2003

An enzootic transmission cycle of Lyme borreliosis spirochetes in the southeastern United States.

Lyme borreliosis, or Lyme disease (LD), is a tick-borne zoonotic infection of biomedical significance, caused by Borrelia burgdorferi sensu lato (s.l.) spirochetes and transmitted by Ixodes species ticks. It usually circulates among wildlife vertebrate reservoirs and vector ticks but may infect humans, causing multisystem problems. In far western and northern North America, the host reservoirs, tick vectors, and genospecies of Borrelia are well known but not so in the southern U.S., where there is controversy as to the presence of "true" LD. Here we report the presence of the LD spirochete B. burgdorferi sensu stricto (s.s.) and Borrelia bissettii, three main reservoir hosts, and two enzootic tick vectors in the southeastern U.S. The two enzootic tick vectors, Ixodes affinis and Ixodes minor, rarely bite humans but are more important than the human biting "bridge" vector, Ixodes scapularis, in maintaining the enzootic spirochete cycle in nature. We also report extraordinary longevities and infections in the reservoir rodents Peromyscus gossypinus, Sigmodon hispidus, and Neotoma floridana.

Animals↗

PubMed2003

Mitochondrial sequence variation in Carlos capensis (Neumann), a parasite of seabirds, collected on Torishima Island in Japan.

Partial mitochondrial 16S ribosomal ribonucleic acid gene sequences in the ticks Carios capensis collected from black-footed albatross. Diomedea nigripes, colonies on Torishima Island, Japan (30 degrees 28'N, 140 degrees 18'E), were examined. The sequence was compared with those of C. capensis from Hawaii, South Carolina, and Texas. The sequences were all identical in ticks from Torishima and 2 from Hawaii. There were 2-3 transitions between the other Hawaiian and Texas ticks and Torishima specimens. Two transitions were also observed when compared with the ticks from South Carolina. The results suggest the possibility of gene flow between tick populations at each of the 2 geographic sites, which probably was accomplished by tick-infested migratory seabirds at their breeding sites. Sequence comparison analysis indicated that the C. capensis ticks are on the branch with C. marginatus and C. mexicanus ticks and not with Ornithodoros. This supports the revision suggested by Klompen and Oliver (1993).

Animals↗

PubMed2001

Cockroach allatostatin-like immunoreactivity in the synganglion of the American dog tick Dermacentor variabilis (Acari: Ixodidae).

Using immunocytochemistry based on a monoclonal antibody against Diploptera punctata allatostatin I and horseradish peroxidase-diaminobenzidine reaction, the presence of allatostatin-like immunoreactivity is demonstrated in the synganglion of Dermacentor variabilis females. The immunoreactive cells are located in the protocerebral, cheliceral, palpal, stomodeal, postesophageal, and opisthosomal regions of the synganglion. Strongly immunoreactive granules accumulate in the boundary area of the subganglia in the preesophageal part of the synganglion. This suggests that the immunoreactive materials may be released directly from there. In addition, a putative neurohemal area is found in the anterior area of the opisthosomal ganglion, where abundant immunoreactive materials are stored. Weak immunoreactivity and fewer immunoreactive cells are seen in newly molted females compared with one month old, unfed females. Thus, the immunoreactive products may be depleted during molting and synthesized in females before feeding.

Animals↗

PubMed2001

Interspecific and geographical variation in the sequence of rDNA expansion segment D3 of Ixodes ticks (Acari: Ixodidae).

The base sequence of the rDNA D3 expansion segment and flanking H14 stem varies between six species of Ixodes ticks (Acari: Ixodidae) where only 33 invariant sites occur among sequences of 123-203 bases in length. Multiple copies of D3 were sequenced from localities across the geographical ranges of four species to investigate deep population genetic structure. Two species, I. pacificus, from western North America, and I. ricinus, from Europe, have no sequence variation indicating a lack of deep genetic structure. One species, I. scapularis, from eastern North America has two forms of the D3 sequence that are distributed differently among northern vs. southern populations, suggesting recent divergence and hybridization. I. persulcatus, from Eurasia, has sequence variation between localities of the order of that observed between other species, suggesting a long history of population isolation and deep genetic structure. With the exception of I. scapularis, sequence variation was not observed within localities. This indicates that cellular processes underpinning concerted evolution have homogenized populations and species for particular rDNA sequence variants.

Animals↗

PubMed2001

Genetic heterogeneity of Borrelia burgdorferi sensu lato in the southern United States based on restriction fragment length polymorphism and sequence analysis.

Fifty-six strains of Borrelia burgdorferi sensu lato, isolated from ticks and vertebrate animals in Missouri, South Carolina, Georgia, Florida, and Texas, were identified and characterized by PCR-restriction fragment length polymorphism (RFLP) analysis of rrf (5S)-rrl (23S) intergenic spacer amplicons. A total of 241 to 258 bp of intergenic spacers between tandemly duplicated rrf (5S) and rrl (23S) was amplified by PCR. MseI and DraI restriction fragment polymorphisms were used to analyze these strains. PCR-RFLP analysis results indicated that the strains represented at least three genospecies and 10 different restriction patterns. Most of the strains isolated from the tick Ixodes dentatus in Missouri and Georgia belonged to the genospecies Borrelia andersonii. Excluding the I. dentatus strains, most southern strains, isolated from the ticks Ixodes scapularis and Ixodes affinis, the cotton rat (Sigmodon hispidus), and cotton mouse (Peromyscus gossypinus) in Georgia and Florida, belonged to Borrelia burgdorferi sensu stricto. Seven strains, isolated from Ixodes minor, the wood rat (Neotoma floridana), the cotton rat, and the cotton mouse in South Carolina and Florida, belonged to Borrelia bissettii. Two strains, MI-8 from Florida and TXW-1 from Texas, exhibited MseI and DraI restriction patterns different from those of previously reported genospecies. Eight Missouri tick strains (MOK-3a group) had MseI patterns similar to that of B. andersonii reference strain 21038 but had a DraI restriction site in the spacer. Strain SCGT-8a had DraI restriction patterns identical to that of strain 25015 (B. bissettii) but differed from strain 25015 in its MseI restriction pattern. Strain AI-1 had the same DraI pattern as other southern strains in the B. bissettii genospecies but had a distinct MseI profile. The taxonomic status of these atypical strains needs to be further evaluated. To clarify the taxonomic positions of these atypical Borrelia strains, the complete sequences of rrf-rrl intergenic spacers from 20 southeastern and Missouri strains were determined. The evolutionary and phylogenetic relationships of these strains were compared with those of the described genospecies in the B. burgdorferi sensu lato species complex. The 20 strains clustered into five separate lineages on the basis of sequence analysis. MI-8 and TXW-1 appeared to belong to two different undescribed genospecies, although TXW-1 was closely related to Borrelia garinii. The MOK-3a group separated into a distinct deep branch in the B. andersonii lineage. PCR-RFLP analysis results and the results of sequence analyses of the rrf-rrl intergenic spacer confirm that greater genetic heterogeneity exists among B. burgdorferi sensu lato strains isolated from the southern United States than among strains isolated from the northern United States. The B. andersonii genospecies and its MOK-3a subgroup are associated with the I. dentatus-cottontail rabbit enzootic cycle, but I. scapularis was also found to harbor a strain of this genospecies. Strains that appear to be B. bissettii in our study were isolated from I. minor and the cotton mouse, cotton rat, and wood rat. The B. burgdorferi sensu stricto strains from the south are genetically and phenotypically similar to the B31 reference strain.

Animals↗

PubMed2001

Radiologist performance in the diagnosis of internal hernia by using specific CT findings with emphasis on transmesenteric hernia.

PURPOSE: To evaluate the performance of radiologists in the diagnosis of internal hernia with specific computed tomographic (CT) findings. MATERIALS AND METHODS: Abdominal CT scans obtained in 42 patients were retrospectively reviewed by three radiologists. The case group consisted of 18 patients with internal hernias (two paraduodenal, 16 transmesenteric); the comparison group was 24 patients with no internal hernia. Images were reviewed in a random and blinded fashion. Individual and group performance was evaluated with receiver operating characteristic (ROC) analysis, and interobserver agreement was measured with Cronbach coefficient alpha. Individual CT signs relevant as predictors of transmesenteric hernia were identified with logistic regression analysis and ranked by their odds ratio and P values. RESULTS: Both paraduodenal hernias were diagnosed by all readers on the basis of CT signs, including a retrogastric saclike mass of small-bowel loops. Diagnosis of transmesenteric hernia was more difficult and variable, with an average accuracy of area under the ROC curve (A(z)) of 77%, sensitivity of 63%, and specificity of 76%. CT signs of transmesenteric hernia were recognized consistently (Cronbach coefficient alpha >or= 0.80) and included a cluster of dilated small-bowel segments and stretching and displacement of mesenteric vessels. Coexisting volvulus and ischemia were diagnosed with low sensitivity (46% and 43%, respectively) but high specificity (96% and 98%, respectively). CONCLUSION: Diagnosis of internal hernia with CT remains difficult. Special attention should be given to the clustering of bowel loops, the mesenteric vessels, and signs of small-bowel obstruction.

Adolescent↗

PubMed2001

Ticks (Acari: Ixodidae) and spirochetes (spirochaetaceae: spirochaetales) recovered from birds on a Georgia Barrier Island.

From September 1997 through July 1999, 300 individuals and 46 species of birds were mist-netted and screened for ticks and spirochetes on St. Catherine's Island, Liberty County, GA. Seventy-six (25%) of the birds were parasitized by a meal intensity of 4.6 ticks. Seasonally, more birds were infested with ticks during the summer (50% in 1998, 34% in 1999) than in spring (15% in 1998, 11% in 1999) or fall (21% in 1997, 20% in 1998), mainly because of severe infestations on some birds by immature stages of the lone star tick, Amblyomma americanum (L.), during this season. Eight species ofticks were recovered from 14 species of birds during this study: A. americanum (74 nymphs, 168 larvae); the blacklegged tick, Ixodes scapularis Say (11 nymphs, 28 larvae), the Gulf Coast tick, Amblyomma maculatum Koch (two nymphs, 29 larvae); Ixodes minor Neumann (16 larvae); the rabbit tick. Haemaphysalis leporispalustris (Packard) (one nymph, 14 larvae); the bird tick Ixodes brunneus Koch (two larvae); the American dog tick, Dermacentor variabilis (Say) (one nymph); and Ixodes affinis Neumann (one larva). The Carolina wren was parasitized by more species of ticks (seven) than any other bird species, followed by the northern cardinal (five), white-throated sparrow (four) and painted bunting (three). Spirochetes were isolated in BSK II medium from one tick (a nymphal A. americanum) and from skin biopsies of 12 (4%) of the individual birds (three downy woodpeckers, three northern waterthrushes, two Carolina wrens, one American redstart, one pine warbler, one Swainson's thrush, and one white-eyed vireo) all in fall 1997. This concentrated phenology of spirochete isolations might reflect periodic amplification or recrudescence of spirochetes in reservoir avian hosts.

Animals↗

PubMed2001

Host associations of ticks parasitizing rodents at Borrelia burgdorferi enzootic sites in South Carolina.

A total of 237 rodents was collected in 4 regions of South Carolina from July 1994 through December 1995. Eight species were collected, including cotton mouse, hispid cotton rat, eastern woodrat, marsh rice rat, white-footed mouse, eastern harvest mouse, golden mouse, and black rat. Of the 1,514 ticks recovered from these hosts, Ixodes minor Neumann, including larvae, nymphs, and adults, was the most abundant species, representing 54% of the total. Only immature stages of other tick species were found, including larvae and nymphs of Dermacentor variabilis (Say), Amblyomma maculatum Koch, Ixodes affinis Neumann, and Ixodes scapularis Say. All 5 tick species parasitized cotton mice, cotton rats, and woodrats, which were the most important small mammal hosts for ticks at the localities studied. Rice rats were hosts of A. maculatum, D. variabilis, and L. minor. Amblyomma maculatum was more strongly associated with cotton rats than other rodent species. Ixodes scapularis was most strongly associated with cotton mice, and I. minor was more strongly associated with both woodrats and cotton mice than other species of rodents. Ixodes minor parasitized hosts in the Coastal Zone only, where among spirochete-infected hosts, it was present in significantly greater numbers than other ticks. Furthermore, I. minor was the only tick species that showed a statistically significant positive association with spirochetal infection in rodents. More I. affinis parasitized spirochete-infected hosts than I. scapularis, but fewer than I. minor. The findings discussed herein provide evidence that implicates I. minor as the possible primary enzootic vector of the Lyme disease spirochete Borrelia burgdorferi Johnson, Schmid, Hyde, Steigerwalt and Brenner in the Coastal Zone of South Carolina. They also indicate that the high level of B. burgdorferi infection in rodents from this region may be a function of the combined involvement of I. minor, I. affinis, and I. scapularis in the enzootic transmission of the spirochete.

Animals↗

PubMed2001

Using CT and cholangiography to diagnose biliary tract carcinoma complicating primary sclerosing cholangitis.

OBJECTIVE: The objective of our study was to determine the value of CT and cholangiography for diagnosing biliary tract carcinoma complicating primary sclerosing cholangitis. MATERIALS AND METHODS: One hundred thirteen abdominal CT examinations and cholangiograms in 45 patients with primary sclerosing cholangitis, including 18 patients with established biliary tract carcinoma, were analyzed for tumor. Four radiologists who were unaware of the presence or absence of carcinoma rated each study as to the probability of malignancy. Receiver operating characteristic curve analysis was used to assess the diagnostic performance of CT and cholangiography, the value of imaging signs, and the degree of inter-observer variation in interpretation. Sensitivity and specificity values were calculated. RESULTS: CT outperformed cholangiography in the detection of carcinoma. The average area under the receiver operating characteristic curve was 0.82 for CT and 0.57 for cholangiography (p = 0.003). Sensitivity and specificity for detecting carcinoma using CT were good, with average values of 82% and 80%, respectively. Average sensitivity and specificity for cholangiography were 54% and 53%, respectively. The most reliable sign of tumor on CT was a discrete mass. Progressive biliary dilatation on sequential studies was the most useful sign on cholangiography. Interobserver agreement assessed using the Cronbach alpha was fair for cholangiography and good for CT. CONCLUSION: CT provides good sensitivity and specificity and significantly outperforms cholangiography in detecting biliary tract carcinoma complicating primary sclerosing cholangitis. Despite limitations, CT and cholangiography provide useful information not otherwise available in the treatment of patients with primary sclerosing cholangitis.

Adult↗

PubMed2001

Reactivity of serum samples of dogs and horses tested by use of class-specific recombinant-based enzyme-linked immunosorbent assays for detection of granulocytic ehrlichiosis.

OBJECTIVE: To test serum samples of dogs and horses by use of class-specific recombinant-based ELISA for establishing a diagnosis of granulocytic ehrlichiosis attributable to infection with organisms from the Ehrlichia phagocytophila genogroup. SAMPLE POPULATION: Serum samples from 43 client-owned dogs and 131 horses (81 with signs of acute illness and 50 without signs of disease). PROCEDURE: Serum samples were analyzed, using ELISA with a recombinant 44-kd protein antigen for IgM and IgG antibodies to the human granulocytic ehrlichiosis (HGE) agent (NCH-1 strain). Western blot analyses, using infected human promyelocytic leukemia cells, were conducted on 38 serum samples of horses and 11 serum samples of dogs to verify reactivity to the 44-kd peptide. RESULTS: IgM or IgG antibodies to the HGE agent were detected in 5 to 28% of dog serum samples and 5 to 37% of horse serum samples. Thirty-five of 38 (92%) horse serum samples had corresponding results on both tests (2 positive results for 26 samples and 2 negative results for 9 samples), using an ELISA for IgG antibodies or immunoblotting for total immunoglobulins. All 11 serum samples of dogs had positive results for both methods. CONCLUSION AND CLINICAL RELEVANCE: These ELISA with recombinant 44-kd antigen are suitable for detecting IgM or IgG antibodies to the HGE agent in serum samples of dogs and horses. Positive results for serum samples of horses from Connecticut, New York, Virginia, and Georgia indicate that the HGE agent is widely distributed in tick-infested areas of the eastern United States.

Animals↗

PubMed2000

Host utilization and seasonal occurrence of Dermacentor species (Acari:Ixodidae) in Missouri, USA.

A total of 3,235 Dermacentor variabilis (Say) specimens were collected from birds, mammals, and by dragging vegetation, and 2,683 D. albipictus (Packard) ticks were collected from deer from 1993 to 1996. Peak seasonal occurrence of adult D. variabilis was from May through July with a precipitous decrease in August. Nymphal D. variabilis populations peaked in June. Peak activity of larvae was bimodal, with one activity peak during late summer (September) and a second peak in winter or early spring. The raccoon, Procyon lotor (L.), was the principal host of adults followed by the Virginia opossum, Didelphis virginiana Kerr. Rodents and the eastern cottontail rabbit, Sylvilagus floridanus (J. A. Allen), were the primary hosts of nymphs. The marsh rice rat, Oryzomys palustris (Harlan), was the principal host of larvae followed by the pine vole, Microtus pinetorum (Le Conte), and white-footed mouse, Peromyscus leucopus (Rafinesque). All stages of D. albipictus were found only on white-tailed deer, Odocoileus virginianus (Zimmermann). Numbers of adult and nymphal D. albipictus peaked in November, whereas larvae peaked in September.

Animals↗

PubMed2000

Isolation, cultivation, and characterization of Borrelia burgdorferi from rodents and ticks in the Charleston area of South Carolina.

Twenty-eight Borrelia burgdorferi isolates from the Charleston, S.C., area are described. This represents the first report and characterization of the Lyme disease spirochete from that state. The isolates were obtained from December 1994 through December 1995 from the tick Ixodes scapularis, collected from vegetation, and from the rodents Peromyscus gossypinus (cotton mouse), Neotoma floridana (eastern wood rat), and Sigmodon hispidus (cotton rat). All isolates were screened immunologically by indirect immunofluorescence with monoclonal antibodies to B. burgdorferi-specific outer surface protein A (OspA) (antibodies H5332 and H3TS) and B. burgdorferi-specific OspB (antibodies H6831 and H614), a Borrelia (genus)-specific antiflagellin antibody (H9724), Borrelia hermsii-specific antibodies (H9826 and H4825), and two polyclonal antibodies (one to Borrelia species and another to B. burgdorferi). Six of the isolates were analyzed by exposing Western blots to monoclonal antibodies H5332, H3TS, H6831, and H9724. All isolates were also analyzed by PCR with five pairs of primers known to amplify selected DNA target sequences specifically reported to be present in the reference strain, B. burgdorferi B-31. The protein profiles of six of the isolates (two from ticks, one from a cotton mouse, two from wood rats, and one from a cotton rat) also were compared by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. We conclude that the 28 Charleston isolates are B. burgdorferi sensu stricto based on their similarities to the B. burgdorferi B-31 reference strain.

Animals↗

PubMed2000

Extrahepatic metastases of hepatocellular carcinoma.

PURPOSE: To determine the relative frequency, incidence, and locations of metastases of hepatocellular carcinoma (HCC), correlate extrahepatic metastatic disease with intrahepatic tumor staging, and determine the computed tomographic (CT) manifestations of HCC metastases. MATERIALS AND METHODS: CT findings in 403 consecutive patients with HCC at our institution since 1992 were reviewed retrospectively. One hundred forty-eight patients with extrahepatic metastatic HCC were identified, and the locations, sizes, and attenuation and enhancement characteristics of the lesions were recorded. RESULTS: A majority (128 [86%] of 148) of patients with extrahepatic HCC foci had either intrahepatic stage IVA tumor (112 [76%] patients) or an intrahepatic stage III tumor (16 [11%] patients) at the occurrence of metastases. The most frequent site of the first detectable metastasis was the lung (58 [39%] patients). Tabulation of all extrahepatic metastatic sites showed the most common to be the lung in 81 (55%) patients, the abdominal lymph nodes in 60 (41%) patients, and the bone in 41 (28%) patients. CONCLUSION: The lung, abdominal lymph nodes, and bone are the most common sites of extrahepatic metastatic HCC. Most extrahepatic HCC occurs in patients with advanced intrahepatic tumor stage (stage IVA). Incidental extrahepatic lesions at CT in patients with stage I or II intrahepatic HCC are unlikely to represent metastatic HCC.

Adolescent↗

PubMed2000

Pretransplantation surveillance for possible hepatocellular carcinoma in patients with cirrhosis: epidemiology and CT-based tumor detection rate in 430 cases with surgical pathologic correlation.

PURPOSE: To determine the prevalence of clinically unsuspected hepatocellular carcinoma (HCC) with advanced cirrhosis and assess the sensitivity of helical computed tomographic (CT) surveillance for tumor detection in these patients. MATERIALS AND METHODS: Prospective direct correlation of CT findings with explanted liver specimen findings was performed in 430 transplant recipients with cirrhosis. The prevalence of clinically unsuspected HCC according to liver disease cause was evaluated. Serum alpha-fetoprotein (AFP) values in patients with and those without tumor were recorded. Prospective and retrospective CT tumor detection was evaluated with respect to CT technique and time from CT to transplantation. RESULTS: HCC was found in 59 (14%) of 430 transplant recipients without suspicion of tumor before referral for transplantation. HCC was most prevalent with hepatitis B (27%) and hepatitis C (22%). Serum AFP values were not sensitive for detection of most small tumors. With triphasic helical CT, the prospective and retrospective rates of identifying patients with tumor were 59% and 68%, respectively; the prospective and retrospective tumor nodule detection rates were 37% and 44%, respectively. Tumor detection rates were highest with CT performed within 67 days before transplantation. CONCLUSION: Clinically unsuspected HCC is most prevalent with cirrhosis secondary to hepatitis B or C, and, when evaluated at CT, is best detected with triphasic contrast material-enhanced helical imaging performed within 67 days before transplantation.

Adolescent↗

PubMed2000

Prevalence of Ehrlichia chaffeensis (Rickettsiales: Rickettsiaceae) in Amblyomma americanum (Acari: Ixodidae) from the Georgia coast and Barrier Islands.

Human monocytic ehrlichiosis is an emerging zoonosis caused by infection with Ehrlichia chaffeensis Anderson, Dawson, Jones & Wilson, which is transmitted to mammals by ixodid ticks. Prevalence of infected ticks and distribution of infection foci indicate relative risk of human exposure to ehrlichiosis and may be influenced by factors such as geographic isolation, human disturbance, and the availability of suitable mammalian reservoir hosts. To test, this, individual and pooled lone star ticks, Amblyomma americanum (L.), were collected from three populations from the Georgia coast (1 mainland site and two barrier islands) and screened for E. chaffeensis. A species-specific, nested polymerase chain reaction (PCR) assay was used to amplify a 572 bp fragment of the E. chaffeensis 16S rRNA gene from infected ticks. PCR product specificity was confirmed by nucleotide sequencing. Our results showed the prevalence of infected ticks to be 0.0% (n = 151), 0.9% (n = 111), and 9.3% (n = 129) for Sapelo Island, St. Catherine's Island, and Fort McAllister, respectively.

Animals↗

PubMed2000

Molecular phylogenetic analysis of ixodid ticks based on the ribosomal DNA spacer, internal transcribed spacer 2, sequences.

An internal transcribed spacer (ITS2) sequence between the 5.8S and 28S rRNA genes was used to estimate the phyletic relationships among Ixodes spp. tick vectors of Lyme disease-causing Borrelia spirochetes. Analysis indicates that Borrelia burgdorferi sensu lato species associated with Lyme disease are found mainly in ticks of the Ixodes ricinus species complex. Other closely related tick species are not known to transmit the Borrelia-that cause Lyme disease in humans, but they appear to have a specific association with other closely related Borrelia species. There is a high degree of concordance in the phylogenetics of Borrelia taxa and the phylogenetic relationships among Ixodes ticks.

Animals↗

PubMed2000

Tick infestations of birds in coastal Georgia and Alabama.

Mist-netted birds were examined for ticks on Jekyll Island, Glynn Co., Georgia (32 bird species) in 1996-1998, and at Fort Morgan, Baldwin Co., Alabama (36 species) in 1998 during fall migration. Sixty-two (14.7%) of 423 birds from Jekyll Island and 22 (13.3%) of 165 birds from Fort Morgan were infested with ticks. The mean number of ticks per infested bird was 2.0 on Jekyll Island and 6.3 at Fort Morgan. Ten species of birds were infested with ticks on Jekyl1 Island where 87% of all ticks were recovered from 3 species: the common yellowthroat (Geothlypis trichas), gray catbird (Dumetella carolinensis), and northern waterthrush (Seiurus noveboracensis). Eight species of birds were infested with ticks at Fort Morgan where 83% of all ticks were recovered from 3 species: the brown thrasher (Toxostoma rufum), swamp sparrow (Melospiza georgiana), and common yellowthroat. Six species of ticks (Amblyomma americanum, Amblyomma maculatum, Haemaphysalis leporispalustris, Ixodes brunneus, Ixodes minor, and Ixodes scapularis) were recovered from the Georgia birds, whereas 3 species (A. maculatum, H. leporispalustris, and Ixodes dentatus) were recovered from the Alabama birds. Attempts to isolate Borrelia burgdorferi sensu stricto, the etiologic agent of Lyme borreliosis, from Ixodes spp. ticks recovered from birds were unsuccessful.

Alabama↗

PubMed2000

Host association and seasonal activity of Amblyomma americanum (Acari: Ixodidae) in Missouri.

From June 1993 through June 1996, 2,260 adult, 4,426 nymphal, and 2,178 larval lone star ticks Amblyomma americanum (L.) were collected in Missouri from vertebrate hosts and by dragging a cloth over vegetation. Prevalence, mean intensity, and relative abundance of each stage varied among hosts. The relative abundance of adult lone star ticks was highest on white-tailed deer, but this stage was also collected from raccoons, opossum, red fox, coyotes, and wild turkey. Nymphs were collected from gray squirrels, eastern cottontail rabbits, opossums, red fox, Carolina wren, and bobwhite quail, but the highest relative abundance occurred on wild turkey, white-tailed deer, and raccoons. Eastern cottontail rabbits, white-tailed deer, raccoons, and squirrels had the highest relative abundance of larval lone star ticks, but they were also found on opossums and wild turkey. The activity of adult lone star ticks was greatest from May through July. The activity for nymphs was highest from May through August, and for larvae, July through September.

Animals↗