Colpodella spp.–like Parasite Infection in Woman, China

The phylum Apicomplexa comprises intracellular protozoa that include many human pathogens. Their nearest relatives are chromerids and colpodellids. We report a case of a Babesia spp.–like relapsing infection caused by a newly described microorganism related to the Apicomplexa. This case is highly suggestive of a previously undescribed type of colpodellid that infects vertebrates

Effects of tick control by acaricide self-treatment of white-tailed deer on host-seeking tick infection prevalence and entomologic risk for Ixodes scapularis-borne pathogens

We evaluated the effects of tick control by acaricide self-treatment of white-tailed deer on the infection prevalence and entomologic risk for three Ixodes scapularis-borne bacteria in host-seeking ticks. Ticks were collected from vegetation in areas treated with the 4-Poster device and from control areas over a 6-year period in five geographically diverse study locations in the Northeastern United States and tested for infection with two known agents of human disease, Borrelia burgdorferi and Anaplasma phagocytophilum, and for a novel relapsing fever-group spirochete related to Borrelia miyamotoi. Overall, 38.2% of adults and 12.5% of nymphs were infected with B. burgdorferi; 8.5% of adults and 4.2% of nymphs were infected with A. phagocytophilum; and 1.9% of adults and 0.8% of nymphs were infected with B. miyamotoi. In most cases, treatment with the 4-Poster device was not associated with changes in the prevalence of infection with any of these three microorganisms among nymphal or adult ticks. However, the density of nymphs infected with B. burgdorferi, and consequently the entomologic risk for Lyme disease, was reduced overall by 68% in treated areas compared to control areas among the five study sites at the end of the study. The frequency of bacterial coinfections in ticks was generally equal to the product of the proportion of ticks infected with a single bacterium, indicating that enzootic maintenance of these pathogens is independent. We conclude that controlling ticks on deer by self-application of acaricide results in an overall decrease in the human risk for exposure to these three bacterial agents, which is due solely to a reduction in tick density. © Copyright 2009, Mary Ann Liebert, Inc

ITMS CAPABILITIES IN ISOMER ANALYSIS .3. CHARACTERIZATION OF METHYL AND DIMETHYL DERIVATIVES OF 8-DESMETHYLSESELINE, POTENTIAL ANTIPROLIFERATIVE AGENTS, BY TANDEM MASS-SPECTROMETRY

Two sets of isomeric pyranocoumarins and pyranochromones have been studied by both electron impact and collision-induced dissociation. The daughter spectra were obtained by ion trap mass spectrometry experiments. Characteristic fragments were obtained in electron impact that allowed differentiation between the chromone and the coumarin systems. Distinction between isomers in each set was achieved by collision-induced daughter spectra of selected parent ions

Quantitative PCR for detection of Babesia microti in Ixodes scapularis ticks and in human blood

Babesia microti, the primary cause of human babesiosis in the United States, is transmitted by Ixodes scapularis ticks; transmission may also occur through blood transfusion and transplacentally. Most infected people experience a viral-like illness that resolves without complication, but those who are immunocompromised may develop a serious and prolonged illness that is sometimes fatal. The geographic expansion and increasing incidence of human babesiosis in the northeastern and midwestern United States highlight the need for high-throughput sensitive and specific assays to detect parasites in both ticks and humans with the goals of improving epidemiological surveillance, diagnosis of acute infections, and screening of the blood supply. Accordingly, we developed a B. microti-specific quantitative PCR (qPCR) assay (named BabMq18) designed to detect B. microti DNA in tick and human blood samples using a primer and probe combination that targets the 18S rRNA gene of B. microti. This qPCR assay was compared with two nonquantitative B. microti PCR assays by testing tick samples and was found to exhibit higher sensitivity for detection of B. microti DNA. The BabMq18 assay has a detection threshold of 10 copies per reaction and does not amplify DNA in I. scapularis ticks infected with Babesia odocoilei, Borrelia burgdorferi, Borrelia miyamotoi, or Anaplasma phagocytophilum. This highly sensitive and specific qPCR assay can be used for detection of B. microti DNA in both tick and human samples. Finally, we report the prevalence of B. microti infection in field-collected I. scapularis nymphs from three locations in southern New England that present disparate incidences of human babesiosis.Lindsay Rollend, Stephen J. Bent, Peter J. Krause, Sahar Usmani-Brown, Tanner K. Steeves, Sarah L. States, Timothy Lepore, Raymond Ryan, Fil Dias, Choukri Ben Mamoun, Durland Fish, and Maria A. Diuk-Wasse

Larval and nymphal tick burdens on <i>Peromyscus leucopus</i> expressed as mean tick count per mouse.

<p>Tick burdens are presented as best fit curves to field derived data from Block Island, RI (top) and Connecticut (bottom) sampled populations (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0115494#pone.0115494.s002" target="_blank">S2 Fig</a>.).</p

Threshold curves for <i>Babesia microti</i> survival at different locations and mouse infection prevalences with <i>Borrelia burgdorferi</i> strain BL206.

<p>This figure shows differences in threshold curves, representing where <i>R</i>₀ = 1, and associated 95% confidence intervals (dotted curves), that separate regions of <i>s_N</i> and <i>c</i> where <i>B. microti</i> is expected to emerge and regions where it is expected to fade out. Threshold curves are contour curves where <i>R</i>₀ is plotted as a function of two variables: the proportion of fed infected larvae that survive to become infectious feeding nymphs, <i>s_N</i>, and the proportion of ticks feeding on <i>Peromyscus leucopus</i>, <i>c.</i> Plots indicate effects of location specific (Block Island and Connecticut) timing of tick activity as well as <i>B. burgdorferi</i> strain BL206 strain prevalence in mice (low  = 0.3 and high  = 0.8) on <i>R</i>₀. Coinfection significantly enhances the likelihood of <i>B. microti</i> establishment in Connecticut and on Block Island when <i>B. burgdorferi</i> prevalence among <i>P. leucopus</i> is high (0.80) (confidence bounds do not overlap). Differences in threshold curves for <i>B. burgdorferi</i> strain B348 are shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0115494#pone.0115494.s003" target="_blank">S3 Fig</a>.</p

Effect of coinfection on larval acquisition of <i>Babesia microti</i>.

<p>The results show the prevalence of <i>B. microti</i> in xenodiagnostic ticks that fed on mice infected with <i>B. microti</i> alone compared to mice coinfected with <i>B. microti</i> and <i>Borrelia burgdorferi</i> strain BL206 (A) or <i>B. burgdorferi</i> strain B348 (B). <i>B. microti</i> parasitemia in mice infected with <i>B. microti</i> alone or <i>B. microti</i> and <i>B. burgdorferi</i> strain B348 are shown in inset above B. The error bars indicate 95% confidence intervals.</p

Laboratory study design.

<p><i>Peromyscus leucopus</i> mice were infected with <i>Babesia microti</i> alone (Group 1 [8 mice]) or coinfected with <i>B. microti</i> and one of two strains of <i>Borrelia burgdorferi:</i> BL206 (Group 2 [3 mice]) or B348 (Group 3 [8 mice]). Xenodiagnosis was performed at 7, 14, 21, 28, 42 days. <i>B. microti</i> infection was determined in ticks at 7, 14, 21, 28, 42 days by qPCR. <i>B. microti</i> infection was determined in mouse blood at weeks 7, 14, 28, 42 days by flow cytometry.</p