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Endemic and tropical human bot infestations are relatively uncommon or unreported in the United States. We report two cases in Connecticut: an unusual furuncular and respiratory myiasis by the rabbit bot Cuterebra buccata (Fab.) (Diptera: Oestridae) in a 74-yr-old male and a case of human bot fly, Dermatobia hominis (L.) (Diptera: Oestridae), myiasis in a 4-yr-old female with a tropical travel history with her family. Identification of C. buccata was based morphologically, in part, on spinal armature and further corroborated by DNA sequencing of the mitochondrial COI gene and comparison to the National Center for Biotechnology Information GenBank DNA sequence database. The resulting annotated sequence data were deposited into the National Center for Biotechnology Information GenBank. The unique medical aspects, and limitations and specifics on bot fly larval habits and identification are discussed.

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AIMS: To investigate the immunoglobulin (Ig) G response after being fed upon by Cimex lectularius L. METHODS AND RESULTS: Participants were fed upon by three male C lectularius insects weekly for a month. Blood was obtained before the feeding and at the last feeding, which was used for immunoblots against bed bug salivary gland extract, with antihuman Immunoglobulin G (IgG) secondary antibodies. No consistent IgG changes developed in 11 humans serially fed upon by C lectularius. Two participants had new IgG responses to proteins at molecular weights of approximately 12-13 kDa, and one had an IgG response to a protein at approximately 40 kDa. At the last study visit, more intense IgG bands to proteins at molecular weights of 12-13 kDa had developed in 55% of participants (6/11) and at molecular weights of ≈30, ≈40 and ≈70 kDa in 45% (5/11) compared with the first study visit. Nitrophorin and apyrase were the most common C lectularius proteins identified with liquid chromatography-tandem mass spectrometry in both crushed bed bug salivary gland extract and post-bed bug feeding extract. CONCLUSIONS: Human participants did not have consistent IgG responses to crushed C lectularius salivary gland extract.

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Human bed bug infestations have undergone a recent global resurgence. The human antiparasitic drug ivermectin has been proposed as a strategy to help control bed bug infestations, but in vivo data are lacking. We allowed separate populations of the common bed bug, Cimex lectularius L., to feed once on a rabbit before and after it was injected subcutaneously with 0.3 mg/kg of ivermectin, and bed bug morbidity and mortality were recorded. Ivermectin levels in the rabbit were measured using high-performance liquid chromatography and mass spectroscopy. Ivermectin blood levels of ∼2 ng/mL caused reductions in bed bug fecundity, and levels of >8 ng/mL caused bed bug death and long-term morbidity including reductions in refeeding, mobility, reproduction, and molting. Gut bacterial cultures from the fed bed bugs showed that ivermectin altered the bed bug gut microbiome.

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The common bed bug, Cimex lectularius L., is a hematophagous ectoparasite that preferentially feeds on humans. Pharmaceuticals present in a person's blood may adversely affect C. lectularius when it feeds. We fed >10,000 C. lectularius on blood samples containing more than 400 different drug doses and drug combinations using an in vitro feeding system to determine insect mortality. The majority of drug doses approximated the peak plasma concentration in humans taking those drugs. Twenty-one drugs were found to cause >17% 12-14-day mortality compared to 8.5% mortality in the control (p < 0.05), but postliminary testing of three of the drugs, famotidine, ethambutol, and primaquine, did not demonstrate an increase in C. lectularius mortality. We also tested 23 drugs for their effects on C. lectularius fecundity. The results may have implications for understanding C. lectularius population dynamics in an infestation.

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Ixodes scapularis Say 1821, the primary vector of several human pathogens in the northeastern and upper Midwestern United States, has considerable genetic and morphological variation throughout its range. Recently, developmental or teratological abnormalities have been observed in this species for the first time, further complicating morphological identification. Here, we report the first evidence of nanism (dwarfism) in I. scapularis, found parasitizing a human host. We used molecular methods and scanning electron microscopy to identify the specimen. Morphological identification confirmed that the specimen is substantially smaller, approximately half the size, than a typical I. scapularis female. Here we discuss the recent reports of teratological abnormalities in I. scapularis, particularly from the Hudson River valley region of the northeastern United States, and highlight the need for additional studies of teratology in this important species and its potential implications in disease transmission.

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The recent resurgence of the common bed bug Cimex lectularius L. throughout western industrialized nations has been facilitated in part by the insect becoming pesticide-resistant. Novel control strategies, including xenointoxication, should be considered to combat C. lectularius. Ivermectin, a U.S. Food and Drug Administration (FDA)-approved treatment for several human parasites, and the antiparasitic drug moxidectin, currently being explored in human clinical trials, were evaluated for efficacy against C. lectularius. Results showed that C. lectularius fed on ivermectin or moxidectin blood concentrations of >25 ng/mL and had significantly higher mortality (50-100 %) than controls (0-6 %) by day 13. Bed bugs that survived a blood meal containing >2.5 ng/mL of ivermectin suffered long-term sequelae including reduced fecundity, feeding difficulty, and incomplete ecdysis. Some insects that survived a blood meal containing ≤75 ng/mL moxidectin were able to feed and reproduce.

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Seafarers are traveling workers, subject to unique exposures and generally isolated from adequate medical care. This case report of paederus dermatitis diagnosed at sea highlights the importance of a multidisciplinary diagnostic approach and telecommunication in providing remote medical advice to isolated traveling workers such as seafarers.

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