Publications by authors named "Paige Adams"

We report an 85-year-old male patient with a medical history significant for psoriasis who presented with a thigh wound that expanded slowly over the course of 9 months. The patient was previously treated with amputation of hand digits for osteomyelitis. Histologic examination of the tissue sample revealed a broad ulceration with large areas of necrosis extending into the subcutis.

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subsp. serotypes are primarily involved in reptile-associated salmonellosis in humans. Here, we report the draft genome sequences of three subsp.

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Venezuelan equine encephalitis (VEE) complex alphaviruses are important re-emerging arboviruses that cause life-threatening disease in equids during epizootics as well as spillover human infections. We conducted a comprehensive analysis of VEE complex alphaviruses by sequencing the genomes of 94 strains and performing phylogenetic analyses of 130 isolates using complete open reading frames for the nonstructural and structural polyproteins. Our analyses confirmed purifying selection as a major mechanism influencing the evolution of these viruses as well as a confounding factor in molecular clock dating of ancestors.

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Chikungunya virus (CHIKV) is a positive sense, single stranded RNA virus in the genus Alphavirus, and the etiologic agent of epidemics of severe arthralgia in Africa, Asia, Europe and, most recently, the Americas. CHIKV causes chikungunya fever (CHIK), a syndrome characterized by rash, fever, and debilitating, often chronic arthritis. In recent outbreaks, CHIKV has been recognized to manifest more neurologic signs of illness in the elderly and those with co-morbidities.

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Irrigation water has been implicated as a likely source of produce contamination by Salmonella enterica. Therefore, the distribution of S. enterica was surveyed monthly in irrigation ponds (n = 10) located within a prime agricultural region in southern Georgia and northern Florida.

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Mayaro virus (MAYV) is an emerging, mosquito-borne alphavirus that causes a dengue-like illness in many regions of South America, and which has the potential to urbanize. Because no specific treatment or vaccine is available for MAYV infection, we capitalized on an IRES-based approach to develop a live-attenuated MAYV vaccine candidate. Testing in infant, immunocompetent as well as interferon receptor-deficient mice demonstrated a high degree of attenuation, strong induction of neutralizing antibodies, and efficacy against lethal challenge.

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The 2013 Produce Safety Rules in Food Safety Modernization Act (FSMA) require regular testing for generic Escherichia coli in agricultural water intended for pre-harvest contact with the edible portion of fresh produce. However, the use of fecal contamination indicators frequently does not correctly reflect distribution of foodborne pathogens such as Salmonella enterica, and ensuring food safety may require direct detection and enumeration of pathogens in agricultural settings. Herein we report the evaluation of different cost-effective methods for quantification, isolation, and confirmation of Salmonella in irrigation pond water and sediment samples.

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Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that causes major epidemics of rash, fever, and debilitating arthritis. Currently, there are no vaccines or antivirals available for prevention or treatment. We therefore generated 2 live-attenuated vaccine candidates based on the insertion of a picornavirus internal ribosome entry site (IRES) sequence into the genome of CHIKV.

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Salmonella and Campylobacter prevalence in stream networks of the Satilla River Basin (SRB) were monitored monthly from August 2007 to August 2009 to study relationships between these pathogens and land use, presence of poultry houses and wastewater treatment plant (WWTP) discharge. Salmonella and Campylobacter were detected at all 10 stream sites and the three sites at the sole wastewater treatment plant (WWTP) in the study area. In all, 43% (129/299) and 62% (96/156) of samples were positive for Salmonella and Campylobacter, respectively, with detection frequency increasing in downstream sites with more poultry production and influence of WWTP discharge.

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This research studied the occurrence of estrogens in the Upper Satilla watershed, Georgia, USA, which was impacted by poultry litter land application and discharge from a sewage treatment plant (STP) receiving poultry wastes. Over 14 months, four estrogens in stream water, sediment, suspended particles, and STP samples were quantified by LC/MS. Estrogens were consistently found in the STP influent with high concentrations while they were below the detection limits in the majority of stream water, suspended particles, and sediment.

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Campylobacter spp., especially Campylobacter jejuni, are common causal agents of gastroenteritis globally. Poultry, contaminated water, and fresh produce are considered to be the main sources for infection by this pathogen.

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Outbreaks of enteritis caused by Escherichia coli O157 associated with fresh produce have resulted in questions about the safety of irrigation water; however, associated risks have not been systematically evaluated. In this study, the occurrence and distribution of the human pathogen E. coli O157 from vegetable irrigation ponds within the Suwannee River Watershed in Georgia were investigated, and the relationship to environmental factors was analyzed.

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The long-term persistence of Modoc virus (MODV) infection was investigated in a hamster model. Golden hamsters (Mesocricetus auratus) were infected by subcutaneous inoculation with MODV, in which fatal encephalitis developed in 12.5% (2 of 16).

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Eastern equine encephalitis virus (EEEV) is a mosquito-borne alphavirus that causes sporadic, often fatal disease outbreaks in humans and equids, and is also a biological threat agent. Two chimeric vaccine candidates were constructed using a cDNA clone with a Sindbis virus (SINV) backbone and structural protein genes from either a North (SIN/NAEEEV) or South American (SIN/SAEEEV) strain of EEEV. The vaccine candidates were tested in a nonhuman primate (NHP) model of eastern equine encephalitis (EEE).

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Venezuelan equine encephalitis virus (VEEV) has been the causative agent for sporadic epidemics and equine epizootics throughout the Americas since the 1930s. In 1969, an outbreak of Venezuelan equine encephalitis (VEE) spread rapidly from Guatemala and through the Gulf Coast region of Mexico, reaching Texas in 1971. Since this outbreak, there have been very few studies to determine the northward extent of endemic VEEV in this region.

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Venezuelan equine encephalitis (VEE) is a re-emerging, mosquito-borne viral disease with the potential to cause fatal encephalitis in both humans and equids. Recently, detection of endemic VEE caused by enzootic strains has escalated in Mexico, Peru, Bolivia, Colombia and Ecuador, emphasizing the importance of understanding the enzootic transmission cycle of the etiologic agent, VEE virus (VEEV). The majority of work examining the viral determinants of vector infection has been performed in the epizootic mosquito vector, Aedes (Ochlerotatus) taeniorhynchus.

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Chikungunya virus (CHIKV) is the mosquito-borne alphavirus that is the etiologic agent of massive outbreaks of arthralgic febrile illness that recently affected millions of people in Africa and Asia. The only CHIKV vaccine that has been tested in humans, strain 181/clone 25, is a live-attenuated derivative of Southeast Asian human isolate strain AF15561. The vaccine was immunogenic in phase I and II clinical trials; however, it induced transient arthralgia in 8% of the vaccinees.

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Animal agriculture in watersheds produces manure bacteria that may contaminate surface waters and put public health at risk. We measured fecal indicator bacteria (commensal Escherichia coli and fecal enterococci) and manure pathogens (Salmonella and E. coli 0157:H7), and physical-chemical parameters in pond inflow, within pond, pond outflow, and pond sediments in three ponds in agricultural watersheds.

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Antiviral compounds that increase the resistance of host tissues represent an attractive class of therapeutic. Here, we show that squalamine, a compound previously isolated from the tissues of the dogfish shark (Squalus acanthias) and the sea lamprey (Petromyzon marinus), exhibits broad-spectrum antiviral activity against human pathogens, which were studied in vitro as well as in vivo. Both RNA- and DNA-enveloped viruses are shown to be susceptible.

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The invasive and fully antigenic trophoblast of the chorionic girdle portion of the equine fetal membranes has the capacity to survive and differentiate after transplantation to ectopic sites. The objectives of this study were to determine i) the survival time of ectopically transplanted allogeneic trophoblast cells in non-pregnant recipient mares, ii) whether equine chorionic gonadotropin (eCG) can be delivered systemically by transplanted chorionic girdle cells, and iii) whether eCG delivered by the transplanted cells is biologically active and can suppress behavioral signs associated with estrus. Ectopically transplanted chorionic girdle survived for up to 105 days with a mean lifespan of 75 days (95% confidence interval 55-94) and secreted sufficient eCG for the hormone to be measurable in the recipients' circulation.

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In situ and in vitro experiments were performed to assess the effects of solar radiation and predation by indigenous microflora on the relative die-off rates of a toxigenic strain of Escherichia coli O157:H7, commensal E. coli, and fecal enterococci in surface waters from ponds in agricultural watersheds. The objective of these experiments was to discern a mechanism of persistence of E.

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Mosquito surveillance was carried out in three forested regions of Trinidad during July 2007-March 2009. A total of 185,397 mosquitoes representing at least 46 species was collected, divided into pools of 1-50 mosquitoes according to species and sex, and screened for arboviruses using cytopathic effect assays on Vero cell monolayers. Eighty-five viruses were isolated, including members of the genera Alphavirus (Mucambo virus; MUCV) and Orthobunyavirus (Caraparu, Oriboca, Bimiti, and Wyeomyia viruses).

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Eastern equine encephalitis virus (EEEV; family Togaviridae, genus Alphavirus) is an arbovirus that causes severe disease in humans in North America and in equids throughout the Americas. The enzootic transmission cycle of EEEV in North America involves passerine birds and the ornithophilic mosquito vector, Culiseta melanura, in freshwater swamp habitats. However, the ecology of EEEV in South America is not well understood.

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Chikungunya virus (CHIKV), a mosquito-borne alphavirus, has traditionally circulated in Africa and Asia, causing human febrile illness accompanied by severe, chronic joint pain. In Africa, epidemic emergence of CHIKV involves the transition from an enzootic, sylvatic cycle involving arboreal mosquito vectors and nonhuman primates, into an urban cycle where peridomestic mosquitoes transmit among humans. In Asia, however, CHIKV appears to circulate only in the endemic, urban cycle.

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Western equine encephalitis virus (WEEV) is a zoonotic alphavirus that circulates in western North America between passerine birds and mosquitoes, primarily Culex tarsalis. Since it was isolated in 1930, WEEV has caused tens of thousands of equine deaths in addition to thousands of human cases. In addition because WEEV is a virus of agricultural importance in addition to a public health threat, we developed two live-attenuated chimeric vaccine candidates that have been shown to be immunogenic and efficacious in mouse models.

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