Recent discovery of widespread Ixodes affinis (Acari: Ixodidae) distribution in North Carolina with implications for Lyme disease studies

Ixodes affinis, which is similar morphologically to Ixodes scapularis, is widely distributed in North Carolina. Collections have documented this species in 32 of 41 coastal plain counties, but no piedmont or mountain counties. This coastal plain distribution is similar to its distribution in Georgia and South Carolina, where it is considered an enzootic vector of Borrelia burgdorferi sensu stricto. An updated list of hosts for I. affinis in the U.S.A. is included, increasing the number to 15 mammal and one bird species. The presence of questing adults of I. affinis from April to November reinforces the need for confirmed identifications of suspected tick vectors of Borrelia spirochetes collected during warm months.

Ectoparasites (sucking lice, fleas and ticks) of small mammals in southeastern Kenya

During 1998-2000, at least 14 species (n = 309) of small mammals were live-trapped and examined for ectoparasites in moist forests of the Taita and Shimba Hills and drier savannah habitats of Nguruman, southeastern Kenya. Ectoparasites were recorded from 11 species of mammals. Five species of sucking lice [Hoplopleura inexpectans Johnson, H. intermedia Kellogg & Ferris, Polyplax reclinata (Nitzsch), P. waterstoni Bedford and Schizophthirus graphiuri Ferris], six species of fleas (Ctenophthalmus leptodactylous Hubbard, Dinopsyllus grypurus Jordan & Rothschild, D. lypusus Jordan & Rothschild, Hypsophthalmus campestris Jordan & Rothschild, Listropsylla basilewskyi Smit and Xiphiopsylla lippa Jordan) and at least six species of ticks (Amblyomma sp., Haemaphysalis sp., Ixodes sp., I. alluaudi Neumann, I. cumulatimpunctatus Schulze, I. muniensis Arthur & Burrow and Rhipicephalus sp.) were recorded from these hosts. Four of the five species of sucking lice were host specific whereas P. reclinata was recorded from two different species of white-toothed shrews, Crocidura spp. Although fleas and ticks were less host specific, C. leptodactylous, D. grypurus and I. cumulatimpunctatus were only recorded from the murid rodent Praomys delectorum (Thomas), Amblyomma sp. was only recorded from the nesomyid rodent Beamys hindei Thomas, Rhipicephalus sp. was only recorded from the murid Lemniscomys striatus (L.) and I. muniensis was only recorded from the dormouse Graphiurus microtis (Noack). More species of ectoparasites and significantly greater infestation prevalences were recorded from small mammals in moist habitats compared with those from the savannah habitat. At least one of the fleas recorded, D. lypusus, is a known vector of Yersinia pestis Lehmann & Neumann, the causative agent of plague, which is present in the region.

The tick fauna of Sulawesi, Indonesia (Acari: Ixodoidea: Argasidae and Ixodidae)

Twenty-six species of ticks are reported from the island of Sulawesi (Celebes), Indonesia. These include two species of soft ticks (Argasidae), Carios batuensis and C. vespertilionis, and the following 24 species of hard ticks (Ixodidae): Amblyomma babirussae, A. breviscutatum, A. cordiferum, A. fimbriatum, A. helvolum, A. testudinarium, A. trimaculatum, A. varanense, Dermacentor atrosignatus, D. steini, Haemaphysalis celebensis, H. hystricis, H. kadarsani, H. papuana, H. psalistos, H. renschi, H. toxopei, H. wellingtoni, Ixodes cordifer, I. granulatus, Rhipicephalus haemaphysaloides, R. (Boophilus) microplus, R. pilans and R. sanguineus. This represents an almost three-fold increase in the number of tick species recorded (9) from Sulawesi since the last available list in 1950. The tick records reported herein represent a culmination of data from specimens in the U.S. National Tick Collection, new records of ticks from endemic tarsiers and associated vertebrates, and literature reviews. Collectively, the tick fauna of Sulawesi shows most affinities with the fauna of southeast Asia but there are distinct faunal elements that show relationships with other Indonesian islands, the Philippines or Australasia, as well as a few tick species with widespread geographical distributions. Some ticks known from Sulawesi have known or potential medical-veterinary significance. These include R. (B.) microplus which is a significant pest of cattle and a vector of the agents of bovine anaplasmosis, I. granulatus which is a vector of Langat virus and Lyme disease spirochetes and has been shown to harbor pathogenic rickettsiae in other parts of its range, and R. sanguineus which is a globally widespread ectoparasite of canines and a vector of canine pathogens and parasites.

Rapid introduction of Lyme disease spirochete, Borrelia burgdorferi sensu stricto, in Ixodes scapularis (Acari: Ixodidae) established at Turkey Point Provincial Park, Ontario, Canada

Borrelia burgdorferi sensu stricto (s.s.) was isolated from questing adult Ixodes scapularis Say ticks collected from Turkey Point Provincial Park (TPPP), Ontario, Canada during 2005-2006. DNA from ten (67%) of 15 pools of ticks was confirmed positive for B. burgdorferi s.s. using polymerase chain reaction (PCR) by targeting the rrf (5S)-rrl (23S) intergenic spacer region and OspA genes. This significant infection rate indicates an accelerated development of B. burgdorferi s.s. in TPPP, because this pathogen was not detected five years previously during sampling of the three motile life stages of I. scapularis. Our study provides the initial report of the presence of B. burgdorferi s.s. in TPPP, which is now endemic for Lyme disease. Ultimately, people and domestic animals are at risk of contracting Lyme disease when they frequent this park.

Gulf Coast ticks (Amblyomma maculatum) and Rickettsia parkeri, United States

Geographic distribution of Rickettsia parkeri in its US tick vector, Amblyomma maculatum, was evaluated by PCR. R. parkeri was detected in ticks from Florida, Georgia, Kentucky, Mississippi, Oklahoma, and South Carolina, which suggests that A. maculatum may be responsible for additional cases of R. parkeri rickettsiosis throughout much of its US range.

Robert Traub (1916-1996): additional publications and patronyms

Full citations are provided for four posthumously published papers coauthored or inspired by the late Robert Traub, the greatest authority on fleas and flea-borne diseases who ever lived. Seven additional patronyms, five posthumous and two newly discovered, bring to 41 the total number of taxa named for this preeminent medical entomologist.

Mixed infections, cryptic diversity, and vector-borne pathogens: evidence from Polygenis fleas and Bartonella species

Coinfections within hosts present opportunities for horizontal gene transfer between strains and competitive interactions between genotypes and thus can be a critical element of the lifestyles of pathogens. Bartonella spp. are Alphaproteobacteria that parasitize mammalian erythrocytes and endothelial cells. Their vectors are thought to be various biting arthropods, such as fleas, ticks, mites, and lice, and they are commonly cited as agents of various emerging diseases. Coinfections by different Bartonella strains and species can be common in mammals, but little is known about specificity and coinfections in arthropod vectors. We surveyed the rate of mixed infections of Bartonella in flea vectors (Polygenis gwyni) parasitizing cotton rats (Sigmodon hispidus) in which previous surveys indicated high rates of infection. We found that nearly all fleas (20 of 21) harbored one or more strains of Bartonella, with rates of coinfection approaching 90%. A strain previously identified as common in cotton rats was also common in their fleas. However, another common strain in cotton rats was absent from P. gwyni, while a rare cotton rat strain was quite common in P. gwyni. Surprisingly, some samples were also coinfected with a strain phylogenetically related to Bartonella clarridgeiae, which is typically associated with felids and ruminants. Finally, a locus (pap31) that is characteristically borne on phage in Bartonella was successfully sequenced from most samples. However, sequence diversity in pap31 was novel in the P. gwyni samples, relative to other Bartonella previously typed with pap31, emphasizing the likelihood of large reservoirs of cryptic diversity in natural populations of the pathogen.

The ticks (Acari: Ixodida: Argasidae, Ixodidae) of Paraguay

The ticks reported in Paraguay, which are here reviewed, can be categorized as 'endemic or established' (Argas persicus or a sibling species, Ornithodoros hasei, O. rostratus, O. rudis, O. talaje/O. puertoricensis, Amblyomma aureolatum, Am. auricularium, Am. brasiliense, Am. cajennense, Am. calcaratum, Am. coelebs, Am. dissimile, Am. dubitatum, Am. incisum, Am. longirostre, Am. nodosum, Am. ovale, Am. pacae, Am. parvum, Am. pseudoconcolor, Am. rotundatum, Am. scutatum, Am. tigrinum, Am. triste, Dermacentor nitens, Haemaphysalis juxtakochi, H. leporispalustris, Ixodes loricatus, Rhipicephalus microplus, and Rh. sanguineus), 'probably endemic or established' (Ar. miniatus, Ar. monachus, Am. argentinae, Am. humerale, Am. naponense, Am. oblongoguttatum, Am. pseudoparvum, I. aragaoi/I. pararicinus, I. auritulus, I. luciae), or 'erroneously reported from Paraguay' (O. coriaceus, Am. americanum and Am. maculatum). Most Paraguayan tick collections have been made in the Chaco phyto-geographical domain, in the central part of the country. Argas persicus or a related species, Am. cajennense, D. nitens, Rh. microplus and Rh. sanguineus are important parasites of domestic animals. Ornithodoros rudis, Am. aureolatum, Am. brasiliense, Am. cajennense, Am. coelebs, Am. incisum, Am. ovale and Am. tigrinum have all been collected from humans. In terms of public health, the collections of Am. cajennense and Am. triste from humans may be particularly significant, as these species are potential vectors of Rickettsia rickettsii and Ri. parkeri, respectively.

Haemodipsus brachylagi n. sp. (Phthiraptera: Anoplura: Polyplacidae), a new sucking louse from the pygmy rabbit in Nevada

The male and female of Haemodipsis brachylagi n. sp. (Phthiraptera: Anoplura) are described from specimens collected from a pygmy rabbit, Brachylagus idahoensis (Merriam) (Lagomorpha: Leporidae), from Nevada. Morphological features that differentiate the new species from other known species of Haemodipsus are elucidated, and an identification key to both sexes of the 3 species now known from this genus in North America is included. Geographical distributions of the other 4 species of Haemodipsus known from other parts of the world are highlighted.

Association of Bartonella with the fleas (Siphonaptera) of rodents and bats using molecular techniques

Bartonella spp. are putatively vector-borne bacterial agents of humans and animals. Fleas have been incriminated as vectors of Bartonella spp. and are suspected of transmitting Bartonella of rodents and bats, but some of these Bartonella spp. have not yet been directly detected in wild caught fleas. We report the molecular detection of Bartonella tribocorum, Bartonella vinsonii subsp. vinsonii, and two novel genotypes of Bartonella from the fleas Xenopsylla cheopis, Ctenophthalmus pseudagyrtes, Sternopsylla texanus, or Orchopeas howardi.

Epifaunistic arthropod parasites of the four-striped mouse, Rhabdomys pumilio, in the Western Cape Province, South Africa

Flea, lice, mite, and tick species associated with 510 Rhabdomys pumilio were collected at 9 localities in the Western Cape Province, South Africa. The aims of the study were first to quantify the species richness, prevalence, and relative mean intensity of infestation of epifaunistic arthropod species associated with R. pumilio, and second to determine temporal variations in the mean abundance of the parasitic arthropods. Each mouse was examined under a stereoscopic microscope and its parasites were removed, identified, and quantified. The epifaunal population was made up of more than 25,000 individuals and included 8 flea, 1 sucking louse, 11 mite, and 13 ixodid tick species. Female-biased sex ratios were noted for 9 (30%) of the ectoparasite species. Three undescribed mite and 1 undescribed tick species were recovered, and new locality records for 2 flea, the louse, and 2 mite species were documented. A phoretic host association between a nonparasitic mite species, Psylloglyphus uilenbergi kivuensis, and 3 flea species, Chiastopsylla rossi, Hypsophthalmus temporis, and Listropsylla agrippinae, was recorded. The mean abundance of the parasitic mite and insect species were higher during the cold wet season, whereas ticks were more numerous during the warm dry months. The large number of ectoparasite species on R. pumilio, a locally abundant and regionally widespread species, is of medical and veterinary importance particularly in relation to the transmission of pathogens such as Anaplasma marginale, Babesia caballi, and Babesia canis to domestic animals; Rickettsia conori; Yersinia pestis; and the viral disease Crimean-Congo hemorrhagic fever to humans.

Three new fleas from Sulawesi, Indonesia (Siphonaptera: Pygiopsyllidae & Ceratophyllidae)

Gryphopsylla maxomydis n. sp. (Pygiopsyllidae), Medwayella rubrisciurae n. sp. (Pygiopsyllidae) and Macrostylophora theresae n. sp. (Ceratophyllidae) are described from endemic rodents in Sulawesi. Gryphopsylla maxomydis was collected from the murids Maxomys musschenbroekii and Paruromys dominator in Central Sulawesi (Sulawesi Tengah). However, M. musschenbroekii appears to be the true host of this flea because it has spiny pelage and G. maxomydis shows morphological adaptations for parasitizing spiny hosts including a remarkable "beak-like" structure on the head. This adatation is similar to a beak-like structure on the head of Gryphopsyllo hopkinsi (Traub) which parasitizes the spiny murid Maxomys whiteheadi in Borneo (Sabah). Medwayella rubrisciurae was collected from the large tree squirrel Rubrisciurus rubriventer in Central Sulawesi and this represents the first report of this flea genus in Sulawesi. Macrostylophora theresce was recorded from the murids Bunomys fratrorum, P. dominator and Rattus xanthurus in North Sulawesi (Sulawesi Utara); most other members of this flea genus parasitize squirrels in the Oriental and Palaearctic zoogeographical regions.

A spotted fever group Rickettsia from an exotic tick species, Amblyomma exornatum (Acari: Ixodidae), in a reptile breeding facility in the United States

Adults and nymphs of Amblyomma exornatum Koch (Acari: Ixodidae), an exotic African tick of monitor lizards, were collected from a Gray's monitor lizard, Varanus olivaceus Hallowell, that died in a reptile facility in Alabama. Nine adult ticks were tested by polymerase chain reaction for rickettsial agents. DNA from a novel spotted fever group Rickettsia was amplified and sequenced from one of the nine ticks. The novel Rickettsia was most similar to "Rickettsia anan," which is associated with Amblyomma from Asia. The detection of a spotted fever group Rickettsia in exotic ticks emphasizes the potential threat posed by the importation and propagation of exotic animals in the United States.

Distribution and characterization of Borrelia burgdorferi isolates from Ixodes scapularis and presence in mammalian hosts in Ontario, Canada

The blacklegged tick, Ixodes scapularis Say (Acari: Ixodidae), has a wide geographical distribution in Ontario, Canada, with a detected range extending at least as far north as the 50th parallel. Our data of 591 adult I. scapularis submissions collected from domestic animals (canines, felines, and equines) and humans during a 10-yr period (1993-2002) discloses a monthly questing activity in Ontario that peaks in May and October. The Lyme disease spirochete Borrelia burgdorferi Johnson, Schmidt, Hyde, Steigerwalt & Brenner was detected in 12.9% of I. scapularis adults collected from domestic hosts with no history of out-of-province travel or exposure at a Lyme disease endemic area. Fifty-three isolates of B. burgdorferi were confirmed positive with polymerase chain reaction by targeting the rrf (5S)-rrl (23S) gene. Using DNA sequencing of the ribosomal species-specific rrf (5S) -rrl (23S) intergenic spacer region, all isolates belong to the pathogenic genospecies B. burgdorferi sensu stricto (s.s.). Nucleotide sequence analysis of a 218- to 220-bp amplicon fragment exhibits six cluster patterns and, collectively, these isolates branch into four phylogenetic cluster groups for both untraveled, mammalian hosts and those with travel to the northeastern United States (New Jersey and New York). Four of five geographic regions in Ontario had strain variants consisting of three different genomic cluster groups. Overall, our molecular characterization of B. burgdorferi s.s. shows genetic heterogeneity within Ontario and displays a connecting link to common strains from Lyme disease endemic areas in the northeastern United States. Moreover, our findings of B. burgdorferi in I. scapularis reveal that people and domestic animals may be exposed to Lyme disease vector ticks, which have wide-ranging distribution in eastern and central Canada.

Ectoparasites of free-ranging pumas and jaguars in the Paraguayan Chaco

Ectoparasites were collected from seven puma (Puma concolor) and seven jaguar (Panthera onca) live-captures (each representing six different animals) in the Paraguayan Chaco from 2002 to 2004. The same five species of ectoparasites were recovered from both host species: the flea, Pulex simulans (total on both hosts combined=30 male, 49 female), and the ticks, Amblyomma cajennense (1 male, 4 female, 46 nymphs, 241 larvae), Amblyomma parvum (42 male, 25 female), Amblyomma tigrinum (1 male, 7 female, 34 larvae) and Amblyomma triste (4 male). There were no statistical differences between the prevalences (percent of hosts infested) for any of these ectoparasite species between the two host species, and only P. simulans showed a significantly higher mean intensity (mean no. of each ectoparasite species per infested host) on one of the host species (jaguar). Clearly, these two large carnivores share similar ectoparasite faunas in the Paraguayan Chaco. However, both carnivores occupy large geographical distributions in the New World and this study, combined with the few previous studies, suggests that their ectoparasite faunas differ slightly in different parts of their respective ranges.

Hard tick calreticulin (CRT) gene coding regions have only one intron with conserved positions and variable sizes

Calreticulin (CRT) is a unique eukaryotic gene. The CRT gene product, calreticulin, was first identified as a calcium binding protein in 1974, but further investigations have indicated that CRT protein performs many functions in cells, including involvement in evading the host's immune system by parasites. Many studies of CRT have been published since the molecule was first discovered; however, the CRT gene exon-intron structure is only known for a limited number of ectoparasite species. In this study, we compared tick CRT genomic sequences to the corresponding cDNA from 28 species and found that 2 exons and 1 intron are present in the tick CRT gene. The intron position is conserved in 28 hard ticks, but intron size and nucleotide sequences vary. Three tick introns possess duplicated fragments and are twice as long as other introns. All tick CRT introns obey the GT-AG rule in the splice-site junctions and are phase 1 introns. By comparing tick CRT introns to those of fruit fly, mouse, and human, we conclude that tick CRT introns belong to the intron-late type. The number and size of CRT introns have increased through the evolution of eukaryotes.

Distribution, seasonality, and hosts of the Rocky Mountain wood tick in the United States

Anaplasma marginale Theiler is a tick-borne pathogen that causes anaplasmosis in cattle. There are approximately 20 tick species worldwide that are implicated as vectors of this pathogen. In the United States, Dermacentor andersoni Stiles and Dermacentor variabilis (Say) are the principal vectors. The risk of transmission of anaplasmosis to cattle has been largely based on the distribution of D. andersoni in the United States. We developed a centralized geographic database that incorporates collection records for D. andersoni from two large national databases. We reviewed the geographic records in each database and postings from MEDLINE and AGRICOLA to produce a national county-level distribution map based on a total of 5,898 records. The records spanned the period from 1903 through 2001 with the majority between 1921 to 1940. Populations of D. andersoni were recorded from 267 counties in 14 states and were distinguished as either established or reported. We found 180 counties with established populations of D. andersoni and 87 counties with reported occurrences in 14 states with the majority of established populations reported from Montana, Idaho, and Oregon. D. andersoni populations in the United States currently extend from the western portions of Nebraska and the Dakotas westward to the Cascade Mountains and from the northern counties of Arizona and New Mexico northward to the Canadian border. The data will be useful for identifying regions at increased risk of acquiring anaplasmosis in the United States. Based upon the database collection records, we also present a summary of recorded hosts for D. andersoni and comments on its seasonal occurrence.

Ticks parasitizing reptiles in the Bahamas

Two species of reptile ticks, Amblyomma dissimile Koch and Amblyomma torrei Pérez Vigueras (Acari: Ixodidae), are reported from the Bahama Islands for the first time. The widespread neotropical (including the Caribbean and southern Florida) A. dissimile was recovered on Andros Island from three species of reptiles all for the first time: the Andros iguana Cyclura cychlura cychlura Cuvier, the Andros curly tail lizard Leiocephalus carinatus coryi Schmidt, and the Andros boa Epicrates striatus fowleri Sheplan and Schwartz. The iguana tick A. torrei, previously known only from Cuba, Puerto Rico and the Cayman Islands, was recovered in the Exuma Islands from the Exuma iguana Cyclura cychlura figginsi Barbour. Mean numbers of ticks per host were as high as 36.6 on Mangrove Cay, Andros Island, and 25.8 on Pasture Cay in the Exuma Islands.