| hemocytic rickettsia-like organisms in ticks: serologic reactivity with antisera to ehrlichiae and detection of dna of agent of human granulocytic ehrlichiosis by pcr. | ixodid ticks were collected from connecticut, massachusetts, missouri, pennsylvania, rhode island, and british columbia (canada) during 1991 to 1994 to determine the prevalence of infection with hemocytic (blood cell), rickettsia-like organisms. hemolymph obtained from these ticks was analyzed by direct and indirect fluorescent antibody (fa) staining methods with dog, horse, or human sera containing antibodies to ehrlichia canis, ehrlichia equi, or rickettsia rickettsii. of the 693 nymphal and a ... | 1995 | 8567911 |
| some factors affecting infestation of white-tailed deer by blacklegged ticks and winter ticks (acari:ixodidae) in southeastern missouri. | a total of 5,669 ticks of 4 species was collected from 515 hunter killed, white-tailed deer. odocoileus virginianus (zimmerman), in southeastern missouri from 1993 through 1995. the american dog tick, dermacentor variabilis (say) (4 adults), the lone star tick, amblyomma americanum (l.) (57 adults, 2 nymphs), the blacklegged tick, ixodes scapularis (say) (3,120 adults), and the winter tick, dermacentor albipictus (packard) (2.059 adults, 436 nymphs, 1 larva) were collected. patterns of adult d. ... | 1997 | 9151505 |
| 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 sprin ... | 2000 | 11201355 |
| infection rates of amblyomma americanum and dermacentor variabilis by ehrlichia chaffeensis and ehrlichia ewingii in southwest missouri. | both ehrlichia chaffeensis and ehrlichia ewingii are causative agents of human ehrlichiosis. both pathogens are transmitted to humans through the bite of an infected lone star tick (amblyomma americanum). since missouri has a high incidence of human monocytic ehrlichiosis, we investigated the prevalence of e. chaffeensis- and e. ewingii-infected a. americanum and dermacentor variabilis (american dog tick) ticks to help assess the relative risk for humans exposed to these vectors. we used a neste ... | 2002 | 12653298 |
| detection of pathogenic ehrlichia in ticks collected at acquisition sites of human ehrlichiosis in missouri. | we collected 385 ticks from sites in missouri associated with human monocytic ehrlichiosis. using pcr, we detected e. chaffeensis or e. ewingii in 2 of 19 pools of adult amblyomma americanum, 0 of 32 pools of dermacentor variabilis, and 6 (18%) of 39 pools of unspeciated nymphal ticks from 3 of 6 sites associated with disease and one site not associated with disease. we also detected a variant of a. phagocytophila in one nymph pool. | 2004 | 15119113 |
| polymerase chain reaction detection of cytauxzoon felis from field-collected ticks and sequence analysis of the small subunit and internal transcribed spacer 1 region of the ribosomal rna gene. | cytauxzoon felis produces a disease in domestic cats in the midwest (u.s.a.), which often leads to a fatal outcome. although the clinical disease process is well described, there are still many unanswered questions about this organism. for example, it is unknown whether species of ticks other than dermacentor variabilis can serve as vectors for transmission. with recent reports of surviving cats from limited geographic areas, another relevant question is the potential for genetically less virule ... | 2005 | 15986625 |
| evidence supporting the presence of borrelia burgdorferi in missouri. | although lyme disease is commonly seen in the southcentral united states, the epidemiology of the disease is poorly defined there. the purpose of this study was to document the presence of borrelia burgdorferi in ticks collected in southeastern missouri and around the city of st. louis. spirochetes were detected and identified as b. burgdorferi by immunofluorescent antibody (ifa) tests using the monoclonal antibody h5332 in 1.9% of amblyomma americanum and 2.0% of dermacentor variabilis ticks co ... | 1994 | 7943575 |
| an acarologic survey and amblyomma americanum distribution map with implications for tularemia risk in missouri. | in the united states, tickborne diseases occur focally. missouri represents a major focus of several tickborne diseases that includes spotted fever rickettsiosis, tularemia, and ehrlichiosis. our study sought to determine the potential risk of human exposure to human-biting vector ticks in this area. we collected ticks in 79 sites in southern missouri during june 7-10, 2009, which yielded 1,047 adult and 3,585 nymphal amblyomma americanum, 5 adult amblyomma maculatum, 19 adult dermacentor variab ... | 2011 | 21363979 |
| distribution and prevalence of cytauxzoon felis in bobcats (lynx rufus), the natural reservoir, and other wild felids in thirteen states. | cytauxzoon felis, a protozoan parasite of wild and domestic felids, is the causative agent of cytauxzoonosis in domestic and some exotic felids in the united states. the bobcat (lynx rufus) is the natural reservoir for this parasite, but other felids such as florida panthers (puma concolor coryii) and domestic cats may maintain long-term parasitemias and serve as reservoirs. experimentally, two tick species, dermacentor variabilis and amblyomma americanum, have demonstrated the ability to transm ... | 2010 | 21071149 |
| a call for renewed research on tick-borne francisella tularensis in the arkansas-missouri primary national focus of tularemia in humans. | arkansas-missouri has emerged as the primary u.s. focus of tularemia, which is caused by the national institute of allergy and infectious diseases category a priority pathogen francisella tularensis, over the past 30 yr. there are several pieces of indirect evidence suggesting that a key role of ticks in the transmission of f. tularensis to humans in arkansas-missouri is the primary reason why tularemia has remained a prominent disease of humans in this two-state area while fading away from othe ... | 2007 | 17547223 |