Stephen M. Rich

Dr. Stephen M. Rich

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Research Focus & Metrics

Academic Career Length

26Years (2001-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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5 January 2015 in Proceedings of the National Academy of Sciences
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Journal Article
Closed access
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MEMostafa A. Elfawal
Mostafa A. Elfawal
MTMelissa J. Towler
Melissa J. Towler
NRNicholas G. Reich
Nicholas G. Reich
PWPamela J. Weathers
Pamela J. Weathers
SRStephen M. Rich
Stephen M. Rich
Significance: Evolution of malaria parasite drug resistance has thwarted efforts to control this deadly disease. Use of drug combinations has been proposed to slow that evolution. Artemisinin is a favorite drug in the global war on malaria and is frequently used in combination therapies. Here we show that using the whole plant ( Artemisia annua ) from which artemisinin is derived can overcome parasite resistance and is actually more resilient to evolution of parasite resistance; i.e., parasites take longer to evolve resistance, thus increasing the effective life span of the therapy.

1 August 2016 in Vector-Borne and Zoonotic Diseases
Verified
Journal Article
Open access
GXGuang Xu
Guang Xu
TMThomas N. Mather
Thomas N. Mather
CHCraig S. Hollingsworth
Craig S. Hollingsworth
SRStephen M. Rich
Stephen M. Rich
A passive surveillance of tick-borne pathogens was conducted over a 7-year period (2006–2012), in which a total of 3551 ticks were submitted to the University of Massachusetts for PCR testing. The vast majority of these ticks were Ixodes scapularis from Massachusetts ( N = 2088) and hence were the focus of further analysis. Two TaqMan duplex qPCR assays were developed to test I. scapularis ticks for the presence of three human pathogens: Borrelia burgdorferi , Anaplasma phagocytophilum , and Babesia microti . I. scapularis submissions were concentrated from Cape Cod, the eastern half of the state outside of the Boston metropolitan area, parts of Franklin and Hampshire counties along the Quabbin Reservoir watershed, and southwestern Berkshire county. Differences in seasonal activity pattern were observed for different developmental stages of I. scapularis . The largest proportion of tick bite victims were age 9 years and under. Nymphal ticks were found more often on lower extremities of their hosts, while more adult ticks were found on the head. Overall infection rate of B. burgdorferi , A. phagocytophilum , and B. microti in human-biting ticks was 29.6%, 4.6%, and 1.8%, respectively. B. burgdorferi -infected ticks were widely distributed, but A. phagocytophilum - and B. microti -infected I. scapularis were found mainly in the eastern half of the state. We found that 1.8%, 1.0%, and 0.4% of ticks were coinfected by B. burgdorferi and A. phagocytophilum , B. burgdorferi and B. microti , and A. phagocytophilum and B. microti , respectively, and 0.3% of ticks had triple coinfection.

5 October 2001 in Molecular and Biochemical Parasitology
Verified
Journal Article
Closed access
XFXiaochuan Feng
Xiaochuan Feng
SRStephen M. Rich
Stephen M. Rich
STSaul Tzipori
Saul Tzipori
GWGiovanni Widmer
Giovanni Widmer

23 May 2018 in Diversity
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Journal Article
Open access
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WTWilliam Tang
William Tang
GXGuang Xu
Guang Xu
COCharles W. O’brien
Charles W. O’brien
MCMichael Calonje
Michael Calonje
NFNico Franz
Nico Franz
SRStephen M. Rich
Stephen M. Rich
Two major lineages of beetles inhabit cycad cones in the New World: weevils (Curculionoidea) in the subtribe Allocorynina, including the genera Notorhopalotria Tang and O’Brien, Parallocorynus Voss, Protocorynus O’Brien and Tang and Rhopalotria Chevrolat, and beetles in the family Erotylidae, including the genus Pharaxonotha Reitter. Analysis of the 16S ribosomal RNA (rRNA) mitochondrial gene as well as cladistic analysis of morphological characters of the weevils indicate four major radiations, with a probable origin on the cycad genus Dioon Lindl. and comparatively recent host shifts onto Zamia L. Analysis of the 16S rRNA gene for erotylid beetles indicates that an undescribed genus restricted to New World Ceratozamia Brongn. is the most early-diverging clade, and this lineage is sister to a large radiation of the genus Pharaxonotha onto Zamia, with apparent host shifts onto Dioon and Ceratozamia. Analysis of beetles are in accord with current models of continental drift in the Caribbean basin, support some proposed species groupings of cycads, but not others, and suggest that pollinator type may impact population genetic structure in their host cycads.

22 January 2022 in Insects
Verified
Journal Article
Open access
PDF file
CLChu-Yuan Luo
Chu-Yuan Luo
PPPatrick Pearson
Patrick Pearson
GXGuang Xu
Guang Xu
SRStephen M. Rich
Stephen M. Rich
A wide range of pathogens, such as bacteria, viruses, and parasites can be transmitted by ticks and can cause diseases, such as Lyme disease, anaplasmosis, or Rocky Mountain spotted fever. Landscape and climate changes are driving the geographic range expansion of important tick species. The morphological identification of ticks is critical for the assessment of disease risk; however, this process is time-consuming, costly, and requires qualified taxonomic specialists. To address this issue, we constructed a tick identification tool that can differentiate the most encountered human-biting ticks, Amblyomma americanum, Dermacentor variabilis, and Ixodes scapularis, by implementing artificial intelligence methods with deep learning algorithms. Many convolutional neural network (CNN) models (such as VGG, ResNet, or Inception) have been used for image recognition purposes but it is still a very limited application in the use of tick identification. Here, we describe the modified CNN-based models which were trained using a large-scale molecularly verified dataset to identify tick species. The best CNN model achieved a 99.5% accuracy on the test set. These results demonstrate that a computer vision system is a potential alternative tool to help in prescreening ticks for identification, an earlier diagnosis of disease risk, and, as such, could be a valuable resource for health professionals.

5 June 2023 in Vector-Borne and Zoonotic Diseases
Verified
Journal Article
Open access
GXGuang Xu
Guang Xu
EFErik Foster
Erik Foster
FRFumiko Ribbe
Fumiko Ribbe
AHAndrias Hojgaard
Andrias Hojgaard
RERebecca J. Eisen
Rebecca J. Eisen
SRStephen M. Rich
Stephen M. Rich
In 2011, Ehrlichia muris eauclairensis (EME) was described as a human pathogen spread by the blacklegged tick, Ixodes scapularis . Until very recently, its reported distribution was limited to the upper midwestern United States, mainly in Minnesota and Wisconsin. In this study, we report the detection of EME DNA in 4 of 16,146 human biting I. scapularis ticks submitted from Massachusetts to a passive tick surveillance program. Active tick surveillance yielded evidence of EME local transmission in the northeastern United States through detection of EME DNA in 2 of 461 host-seeking I. scapularis nymphs, and in 2 white-footed mice ( Peromyscus leucopus ) of 491 rodent samples collected in the National Ecological Observatory Network (NEON) Harvard Forest site in Massachusetts.