Last data update: May 13, 2024. (Total: 46773 publications since 2009)
Records 1-22 (of 22 Records) |
Query Trace: Iverson C[original query] |
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Prevalent, protective, and convergent IgG recognition of SARS-CoV-2 non-RBD spike epitopes in COVID-19 convalescent plasma (preprint)
Voss WN , Hou YJ , Johnson NV , Kim JE , Delidakis G , Horton AP , Bartzoka F , Paresi CJ , Tanno Y , Abbasi SA , Pickens W , George K , Boutz DR , Towers DM , McDaniel JR , Billick D , Goike J , Rowe L , Batra D , Pohl J , Lee J , Gangappa S , Sambhara S , Gadush M , Wang N , Person MD , Iverson BL , Gollihar JD , Dye J , Herbert A , Baric RS , McLellan JS , Georgiou G , Lavinder JJ , Ippolito GC . bioRxiv 2020 Although humoral immunity is essential for control of SARS-CoV-2, the molecular composition, binding epitopes and effector functions of the immunoglobulin G (IgG) antibodies that circulate in blood plasma following infection are unknown. Proteomic deconvolution of the circulating IgG repertoire (Ig-Seq (1) ) to the spike ectodomain (S-ECD (2) ) in four convalescent study subjects revealed that the plasma response is oligoclonal and directed predominantly (>80%) to S-ECD epitopes that lie outside the receptor binding domain (RBD). When comparing antibodies directed to either the RBD, the N-terminal domain (NTD) or the S2 subunit (S2) in one subject, just four IgG lineages (1 anti-S2, 2 anti-NTD and 1 anti-RBD) accounted for 93.5% of the repertoire. Although the anti-RBD and one of the anti-NTD antibodies were equally potently neutralizing in vitro , we nonetheless found that the anti-NTD antibody was sufficient for protection to lethal viral challenge, either alone or in combination as a cocktail where it dominated the effect of the other plasma antibodies. We identified in vivo protective plasma anti-NTD antibodies in 3/4 subjects analyzed and discovered a shared class of antibodies targeting the NTD that utilize unmutated or near-germline IGHV1-24, the most electronegative IGHV gene in the human genome. Structural analysis revealed that binding to NTD is dominated by interactions with the heavy chain, accounting for 89% of the entire interfacial area, with germline residues uniquely encoded by IGHV1-24 contributing 20% (149 Å (2) ). Together with recent reports of germline IGHV1-24 antibodies isolated by B-cell cloning (3,4) our data reveal a class of shared IgG antibodies that are readily observed in convalescent plasma and underscore the role of NTD-directed antibodies in protection against SARS-CoV-2 infection. |
A cluster of health symptoms after a law enforcement operation: A case study
Chiu SK , Hornsby-Myers J , Iverson C , Trout D . Saf Health Work 2022 13 (4) 507-511 Law enforcement officers (LEOs) often encounter rapidly changing and uncontrolled situations that expose them to various hazards. A law enforcement agency requested an evaluation by the National Institute for Occupational Safety and Health (NIOSH) when multiple LEOs reported illness after executing a search warrant and taking a suspect into custody. NIOSH investigators interviewed LEOs and reviewed medical records, forensic laboratory results for collected evidence, and environmental testing results of samples taken after the operation. Two-thirds (25 of 38) of LEOs who participated in the operation reported 1 symptom. Eleven LEOs met a case definition for influenza-like illness (ILI). Members of one unit were more likely to have ILI than non-members (prevalence ratio (PR), 4.1; 95% confidence interval (CI): 1.3-13.0; p=0.01). Influenza vaccination was associated with a lower prevalence of ILI (PR, 0.2; 95% CI, 0.1-0.9; p =0.02). Preventing employees from working while ill and annual influenza vaccination might prevent similar occurrences. |
Factors beyond compensation associated with uptake of voluntary medical male circumcision in Zambia
Ong KS , Laube C , Mohan D , Iverson L , Kaonga A , Chituwo O , Kamboyi R , Kabila M , Toledo C . AIDS Behav 2022 27 (6) 1836-1848 Voluntary medical male circumcision (VMMC) provides partial protection against female-to-male transmission of HIV. The Maximizing the Impact of Voluntary Medical Male Circumcision in Zambia (MAXZAM) project was a phased implementation of a demand generation strategy for VMMC through economic compensation. Previously published findings showed increased uptake of VMMC when compensation was provided. This paper is a follow-up evaluation of the MAXZAM project exploring additional factors associated with uptake of VMMC. Factors found associated include the outreach setting in which men were approached, number of information sources seen, heard, or read about VMMC, their self-reported HIV risk behaviors, their self-reported intention to go through the procedure, and their behavioral-psychographic profile. The findings highlight the importance of considering general (e.g., intensifying mass communications and targeting specific settings) and person-centered demand generation approaches (e.g., considering the client's psychographic profile and HIV risk level) to maximize effect on VMMC uptake. |
Prevalent, protective, and convergent IgG recognition of SARS-CoV-2 non-RBD spike epitopes.
Voss WN , Hou YJ , Johnson NV , Delidakis G , Kim JE , Javanmardi K , Horton AP , Bartzoka F , Paresi CJ , Tanno Y , Chou CW , Abbasi SA , Pickens W , George K , Boutz DR , Towers DM , McDaniel JR , Billick D , Goike J , Rowe L , Batra D , Pohl J , Lee J , Gangappa S , Sambhara S , Gadush M , Wang N , Person MD , Iverson BL , Gollihar JD , Dye J , Herbert A , Finkelstein IJ , Baric RS , McLellan JS , Georgiou G , Lavinder JJ , Ippolito GC . Science 2021 372 (6546) 1108-1112 The molecular composition and binding epitopes of the immunoglobulin G (IgG) antibodies that circulate in blood plasma following SARS-CoV-2 infection are unknown. Proteomic deconvolution of the IgG repertoire to the spike glycoprotein in convalescent subjects revealed that the response is directed predominantly (>80%) against epitopes residing outside the receptor-binding domain (RBD). In one subject, just four IgG lineages accounted for 93.5% of the response, including an N-terminal domain (NTD)-directed antibody that was protective against lethal viral challenge. Genetic, structural, and functional characterization of a multi-donor class of "public" antibodies revealed an NTD epitope that is recurrently mutated among emerging SARS-CoV-2 variants of concern. These data show that "public" NTD-directed and other non-RBD plasma antibodies are prevalent and have implications for SARS-CoV-2 protection and antibody escape. |
Clinical, diagnostic, and epidemiological features of a community-wide outbreak of canine leptospirosis in a low-prevalence region (Maricopa County, Arizona)
Iverson SA , Levy C , Yaglom HD , Venkat HL , Artus A , Galloway R , Guagliardo SAJ , Reynolds L , Kretschmer MJ , LaFerla Jenni ME , Woodward P , Reindel AA , Tarrant S , Sylvester T , Klein R , Mundschenk P , Sunenshine R , Schafer IJ . J Am Vet Med Assoc 2021 258 (6) 616-629 OBJECTIVE: To describe clinical, diagnostic, and epidemiological features of an outbreak of leptospirosis in dogs in Maricopa County, Ariz, from January 2016 through June 2017. ANIMALS: 71 case and 281 control dogs. PROCEDURES: Cases were classified as confirmed, probable, suspect, or not a case on the basis of medical record data that fulfilled clinical, diagnostic, and epidemiological criteria. Potential exposures were assessed by owner survey. For the case-control investigation, control dogs were recruited through owner completion of a July 2017 survey. Summary statistics and ORs for case dog lifestyle factors were reported. RESULTS: 54 dogs were classified as confirmed and 17 as probable cases. For 4 dogs of a household cluster (5 confirmed and 3 probable), the highest microscopic agglutination titer was for serovar Djasiman (Leptospira kirschneri detected by PCR assay), and for 13 dogs of a community outbreak (49 confirmed and 14 probable cases), the highest titer was for serovar Canicola (Leptospira interrogans detected by PCR assay). The 44 case dogs included in the case-control investigation were 7.7 (95% CI, 3.5 to 16.7) and 2.9 times (95% CI, 1.3 to 6.6) as likely as control dogs to have visited dog daycare or to have been kenneled overnight at a boarding facility, respectively, 30 days prior to the onset of clinical signs or diagnosis. CONCLUSIONS AND CLINICAL RELEVANCE: Diagnostic and epidemiological findings indicated 2 outbreaks. Transmission where dogs congregated likely propagated the community outbreak. Outbreaks of leptospiral infections can occur in regions of low prevalence, and a dog's exposure to areas where dogs congregate should be considered when making Leptospira vaccination recommendations. |
Heat-associated mortality in a hot climate: Maricopa County, Arizona, 2006-2016
Iverson SA , Gettel A , Bezold CP , Goodin K , McKinney B , Sunenshine R , Berisha V . Public Health Rep 2020 135 (5) 631-639 OBJECTIVES: Maricopa County, Arizona (2017 population about 4.3 million), is located in the Sonoran Desert. In 2005, the Maricopa County Department of Public Health (MCDPH) established a heat-associated mortality surveillance system that captures data on circumstances of death for Maricopa County residents and visitors. We analyzed 2006-2016 surveillance system data to understand the characteristics and circumstances of heat-associated deaths. METHODS: We classified heat-associated deaths based on International Classification of Diseases, Tenth Revision codes (X30, T67.X, and P81.0) and phrases (heat exposure, environ, exhaustion, sun, heat stress, heat stroke, or hyperthermia) in part I or part II of the death certificate. We summarized data on decedents' demographic characteristics, years lived in Arizona, location of death (indoors vs outdoors), presence and functionality of air conditioning, and whether the decedent had been homeless. We examined significant associations between variables by using the Pearson χ(2) tests and logistic regression. RESULTS: During 2006-2016, MCDPH recorded data on 920 heat-associated deaths, 912 of which included location of injury. Of 565 (62%) heat-associated deaths that occurred outdoors, 458 (81%) were among male decedents and 243 (43%) were among decedents aged 20-49. Of 347 (38%) heat-associated deaths that occurred indoors, 201 (58%) were among decedents aged ≥65. Non-Arizona residents were 5 times as likely as Arizona residents to have a heat-associated death outdoors (P < .001). Of 727 decedents with data on duration of Arizona residency, 438 (60%) had resided in Arizona ≥20 years. CONCLUSIONS: Ongoing evaluation of interventions that target populations at risk for both outdoor and indoor heat-associated deaths can further inform refinement of the surveillance system and identify best practices to prevent heat-associated deaths. |
Clinical sequelae associated with unresolved tropical splenomegaly in a cohort of recently resettled Congolese refugees in the United States - multiple states, 2015-2018
Zambrano LD , Jentes E , Phares C , Weinberg M , Kachur SP , Basnet MS , Klosovsky A , Mwesigwa M , Naoum M , Nsobya SL , Samson O , Goers M , McDonald R , Morawski B , Njuguna H , Peak C , Laws R , Bakhsh Y , Iverson SA , Bezold C , Allkhenfr H , Horth R , Yang J , Miller S , Kacka M , Davids A , Mortimer M , Stauffer W , Marano N . Am J Trop Med Hyg 2020 103 (1) 485-493 Tropical splenomegaly is often associated with malaria and schistosomiasis. In 2014 and 2015, 145 Congolese refugees in western Uganda diagnosed with splenomegaly during predeparture medical examinations underwent enhanced screening for various etiologies. After anecdotal reports of unresolved splenomegaly and complications after U.S. arrival, patients were reassessed to describe long-term clinical progression after arrival in the United States. Post-arrival medical information was obtained through medical chart abstraction in collaboration with state health partners in nine participating states. We evaluated observed splenomegaly duration and associated clinical sequelae between 130 case patients from eastern Congo and 102 controls through adjusted hierarchical Poisson models, accounting for familial clustering. Of the 130 case patients, 95 (73.1%) had detectable splenomegaly after arrival. Of the 85 patients with records beyond 6 months, 45 (52.9%) had persistent splenomegaly, with a median persistence of 14.7 months (range 6.0-27.9 months). Of the 112 patients with available results, 65 (58.0%) patients had evidence of malaria infection, and the mean splenomegaly duration did not differ by Plasmodium species. Refugees with splenomegaly on arrival were 43% more likely to have anemia (adjusted relative risk [aRR]: 1.43, 95% CI: 1.04-1.97). Those with persistent splenomegaly were 60% more likely (adjusted relative risk [aRR]: 1.60, 95% CI: 1.15-2.23) to have a hematologic abnormality, particularly thrombocytopenia (aRR: 5.53, 95% CI: 1.73-17.62), and elevated alkaline phosphatase (aRR: 1.57, 95% CI: 1.03-2.40). Many patients experienced persistent splenomegaly, contradicting literature describing resolution after treatment and removal from an endemic setting. Other possible etiologies should be investigated and effective treatment, beyond treatment for malaria and schistosomiasis, explored. |
Identifying and mapping potentially adverse discontinuities in underground excavations using thermal and multispectral UAV imagery
Turner RM , MacLaughlin MM , Iverson SR . Eng Geol 2020 266 105470 Geotechnical mapping, rock mass characterization, and inspections of underground excavations are critical to ensuring that excavation geometry and ground support design are appropriate for stable conditions. A lack of access, poor timing, or hazardous conditions are all factors that can prohibit engineering personnel from collecting high-quality data in the field. Advances in unmanned aerial vehicles (UAV) and portable sensor technology now allow engineering personnel to remotely capture data from underground workings that can be used for developing designs, generating inputs for analyses, and making more informed decisions. Ground falls are a source of many accidents in the underground environment, and they are the focus of many geotechnical investigations and analyses. In this study, the authors investigated how portable UAV-mounted thermal and multispectral imagers could be used to detect and quantify adverse geological discontinuities in hard rock masses that are structurally controlled. Multiple thermal, multispectral, RGB (red, green, and blue), and LiDAR (light detection and ranging) data sets were captured from 5 flights in sub-level open stopes at the Barrick Golden Sunlight Mine in the state of Montana in the western United States of America. Using off-the-shelf software, the thermal, RGB, and multispectral images were processed to create individual three-dimensional point clouds and meshes, which were georeferenced using the LiDAR data. Discontinuities identified in the three-dimensional point clouds and meshes were mapped using tools found in the freeware CloudCompare. One of the thermal models identified wedges that had developed in the crown pillar of an open stope, and 4 of the multispectral models contained enough detail for mapping individual discontinuities. The results of this investigation indicate that these portable imagers are viable tools that can be used to aid engineering personnel in identifying and mapping adverse geological discontinuities and unique rock mass composition. The techniques for capturing, processing, and interpreting thermal and multispectral imagery captured in underground excavations are described in this paper and can be used as the basis for future investigations at individual underground sites. |
Knowledge, attitudes, and practices among veterinarians during an outbreak of canine leptospirosis-Maricopa County, Arizona, 2017
LaFerla Jenni M , Woodward P , Yaglom H , Levy C , Iverson SA , Kretschmer M , Jarrett N , Dooley E , Narang J , Venkat H . Prev Vet Med 2019 172 104779 Leptospirosis, caused by Leptospira spp., is a zoonotic bacterial disease important to both human and animal health. Six pathogenic serovars are currently known to commonly infect and cause disease in dogs in the United States. While canine leptospirosis infection is historically rare in Arizona (</=5 cases reported annually) (ADHS unpublished data) several clusters were reported in Maricopa County (MC) during February 2016-January 2017. Public health initiated an outbreak response and developed a knowledge, attitudes, and practices survey for veterinarians. The goals were to determine awareness and general attitudes about canine leptospirosis and to identify gaps in veterinarians' knowledge in treatment and prevention. We distributed a 40-question self-administered online survey to 1058 Arizona Veterinary Medical Association members, made available during February 9-May 15, 2017. We analyzed the results using Pearson's Chi-squared or Fisher's exact test; a P-value <0.05 was considered statistically significant. We analyzed 202 complete responses. Veterinarians from 10 (66%) of 15 Arizona counties were represented. MC practices were more likely to stock leptospirosis vaccine (80%) than other counties combined (58%) (P=0.004). The average composite knowledge score was 24.4 out of 38 (range 12-37, median 24); 49% of respondents demonstrated higher knowledge as defined by authors, largely in identification of leptospirosis risk factors (86%) and routes of exposure (73%). Fewer than half (45%) of respondents correctly identified the length of time bacteria can be shed in dogs' urine. Eighty-one percent of respondents demonstrated lower knowledge about clinical signs associated with leptospirosis; only 47% of respondents identified eight clinical signs commonly associated with leptospirosis. Sixty-one percent of MC respondents agreed that leptospirosis is an important canine disease in their geographic area, while only 40% of other county respondents agreed (P=0.03). Seventy percent of respondents identified diagnostic testing options. The majority correctly selected infection-control practices in line with recommendations from 2 national clinical guidelines. More respondents would recommend leptospirosis vaccination if dogs traveled or lived in rural areas (87-96%) than if dogs attended day care or were boarded (63%). We identified opportunities for education, including the local epidemiology of leptospirosis, transmission prevention strategies, vaccine safety, testing, clinical identification, and emerging risk factors. Our findings will help guide the design of educational materials for small animal veterinarians in Arizona regarding recommendations for prevention of animal and human leptospirosis infections; these efforts could also shift the culture of reporting companion animal diseases to improve future One Health collaborations. |
Despite high-risk exposures, no evidence of zoonotic transmission during a canine outbreak of leptospirosis
Guagliardo SAJ , Iverson SA , Reynolds L , Yaglom H , Venkat H , Galloway R , Levy C , Reindel A , Sylvester T , Kretschmer M , LaFerla Jenni M , Woodward P , Beatty N , Artus A , Klein R , Sunenshine R , Schafer IJ . Zoonoses Public Health 2019 66 (2) 223-231 Leptospirosis is a bacterial zoonosis that affects many mammals, including humans and dogs; dogs can transmit the bacteria to humans, but the frequency of transmission and highest risk exposures are poorly understood. During 2016-2017, the Maricopa County Department of Public Health, Arizona Department of Health Services and Centers for Disease Control and Prevention investigated the zoonotic potential of a canine leptospirosis outbreak in the Phoenix metro area. We identified symptomatic persons exposed to canine leptospirosis cases by conducting active and passive surveillance. We tested dog owners (n = 9) and animal care providers (n = 109) for serological evidence of Leptospira spp. infection (via the microscopic agglutination test [MAT]) and interviewed these persons about their specific exposures to canine cases and general exposures to canine blood and urine. Through surveillance, seven symptomatic persons were identified; six were tested and all were negative by MAT, and of these six, four persons were negative by PCR (two did not have PCR testing). All serosurvey participants (n = 118) were also seronegative. Among animal care providers, bare skin contact with urine/blood from a canine case was reported by 23.2%; two persons reported dog urine splashing in their face. Veterinary technicians were more likely to have bare skin contact with blood from a canine case compared to veterinarians and boarding facility staff (p < 0.001). Infection control practices were inconsistent; when working with specimens from a canine leptospirosis case, 44.6% of participants reported always wearing gloves when working with urine (i.e., collecting specimens), and 54.5% always wore gloves when working with blood. Veterinary technicians were also most likely to engage in all activities involving potential urine/blood contact, such as conducting laboratory tests (p < 0.01). We therefore recommend that veterinary technicians specifically receive targeted education about infection control practices. Our results suggest that dog-to-human transmission of leptospirosis is uncommon. |
Community-wide recreational water-associated outbreak of cryptosporidiosis and control strategies - Maricopa County, Arizona, 2016
Iverson SA , Fowle N , Epperson G , Collins J , Zusy S , Narang J , Matthews J , Hlavsa MC , Roellig D , Sylvester T , Klein R , Sunenshine R . J Environ Health 2018 81 (4) 14-21 We describe a 2016 community-wide recreational water-associated cryptosporidiosis outbreak investigation and response in Maricopa County, Arizona. Persons with a laboratory-confirmed illness were interviewed using a standardized questionnaire that assessed exposures 2 weeks before symptom onset. A convenience sample of managers and operators of chlorine-treated public aquatic facilities was surveyed regarding permanent supplemental treatment systems for Cryptosporidium. Among 437 cases identified (median age 12, range <1-75 years), 260 persons were interviewed. Public-treated recreational water was the most frequently reported exposure (177, 68%) of interviewed persons; almost 1 in 5 (43, 17%) swam when diarrhea was ongoing. After the 2016 outbreak, managers of some facilities expressed intentions to install supplementary water treatment systems, and by May 2017, at least one large facility installed an ultraviolet light system. Strategies to prevent additional illness included community messaging, education, and targeted remediation of affected facilities on the basis of interviews. Challenges to remediation during a cryptosporidiosis outbreak in a large jurisdiction with primarily outdoor pools underscore the importance of promoting healthy swimming practices that help prevent contamination from occurring. |
Talaromycosis (penicilliosis) in a cynomolgus macaque
Iverson WO , Karanth S , Wilcox A , Pham CD , Lockhart SR , Nicholson SM . Vet Pathol 2018 55 (4) 300985818758468 A sexually mature Chinese-origin female Macaca fascicularis assigned to the high-dose group in a 26-week toxicology study with an experimental immunomodulatory therapeutic antibody (a CD40 L antagonist fusion protein) was euthanized at the scheduled terminal sacrifice on study day 192. The animal was healthy at study initiation and remained clinically normal throughout the study. On study day 141, abnormal clinical pathology changes were found during a scheduled evaluation; splenomegaly was detected on study day 149 and supported by ultrasound examination. At the scheduled necropsy, there was marked splenomegaly with a nodular and discolored appearance. Cytologic examination of a splenic impression smear revealed yeast-like organisms within macrophages. Histologically, there was disseminated systemic granulomatous inflammation with 2- to 3-mum oval, intracytoplasmic yeast-like organisms in multiple organs identified as Talaromyces (Penicillium) marneffei. This organism, not previously reported as a pathogen in macaques, causes an important opportunistic infection in immunosuppressed humans in specific global geographic locations. |
Notes from the Field: Cluster of Acute Flaccid Myelitis in Five Pediatric Patients - Maricopa County, Arizona, 2016.
Iverson SA , Ostdiek S , Prasai S , Engelthaler DM , Kretschmer M , Fowle N , Tokhie HK , Routh J , Sejvar J , Ayers T , Bowers J , Brady S , Rogers S , Nix WA , Komatsu K , Sunenshine R . MMWR Morb Mortal Wkly Rep 2017 66 (28) 758-760 In 2016, CDC saw an increase in cases of acute flaccid myelitis (AFM); 144 persons in 37 states and the District of Columbia were confirmed to have AFM. After investigations in California (1) and Colorado (2) in 2014, CDC characterized AFM as an acute flaccid paralysis (AFP) distinguishable by magnetic resonance imaging (MRI) abnormalities of the gray matter of the anterior and posterior spinal cord segments, involving one or more spinal segments (3). Although certain viruses (e.g., nonpoliovirus enteroviruses, adenoviruses, and West Nile virus) can cause rare cases of AFP, and findings from the 2014 outbreak investigations indicated that enterovirus D68 (EV-D68) was temporally associated with AFM, no viral etiology for AFM has been definitively established (3). In September 2016, an acute care hospital in Arizona notified the Maricopa County Department of Public Health (MCDPH) of a suspected case of AFM and subsequent cluster of 11 children who were evaluated with similar neurologic deficits; differential diagnoses included transverse myelitis and AFM. The Maricopa County Department of Public Health, in cooperation with the Arizona Department of Health Services, CDC, the Translational Genomics Research Institute (TGen, Flagstaff, Arizona), and the acute care hospital, initiated an investigation to confirm AFM cases and identify an etiology. | The 2015 Council of State and Territorial Epidemiologists and CDC case definition for probable AFM requires acute onset of flaccid limb weakness and cerebrospinal fluid (CSF) pleocytosis (CSF white blood cell [WBC] count >5/mm3 when corrected for red blood cells). A confirmed case must have an MRI demonstrating lesions restricted primarily to the gray matter of the spinal cord, in addition to acute onset of flaccid limb weakness (4). Based on medical chart abstraction and review of the MRI images, a CDC neurology subject matter expert verified four confirmed cases of AFM and one probable case. Among the six patients whose cases did not meet the AFM confirmed or probable case definition, two had focal limb weakness and pleocytosis (CSF WBC = 7/mm3 and 22/mm3, respectively), but MRI results indicated alternative etiologies (acute disseminated encephalomyelitis and neuromyelitis optica, respectively). The case that met the probable case definition had pleocytosis (CSF WBC = 7/mm3), but MRI findings were inconsistent with AFM, and no other plausible diagnosis was identified. |
Using molecular characterization to support investigations of aquatic facility-associated outbreaks of cryptosporidiosis - Alabama, Arizona, and Ohio, 2016
Hlavsa MC , Roellig DM , Seabolt MH , Kahler AM , Murphy JL , McKitt TK , Geeter EF , Dawsey R , Davidson SL , Kim TN , Tucker TH , Iverson SA , Garrett B , Fowle N , Collins J , Epperson G , Zusy S , Weiss JR , Komatsu K , Rodriguez E , Patterson JG , Sunenshine R , Taylor B , Cibulskas K , Denny L , Omura K , Tsorin B , Fullerton KE , Xiao L . MMWR Morb Mortal Wkly Rep 2017 66 (19) 493-497 Cryptosporidiosis is a nationally notifiable gastrointestinal illness caused by parasitic protozoa of the genus Cryptosporidium, which can cause profuse, watery diarrhea that can last up to 2-3 weeks in immunocompetent patients and can lead to life-threatening wasting and malabsorption in immunocompromised patients. Fecal-oral transmission of Cryptosporidium oocysts, the parasite's infectious life stage, occurs via ingestion of contaminated recreational water, drinking water, or food, or following contact with infected persons or animals, particularly preweaned bovine calves (1). The typical incubation period is 2-10 days. Since 2004, the annual incidence of nationally notified cryptosporidiosis has risen approximately threefold in the United States (1). Cryptosporidium also has emerged as the leading etiology of nationally notified recreational water-associated outbreaks, particularly those associated with aquatic facilities (i.e., physical places that contain one or more aquatic venues [e.g., pools] and support infrastructure) (2). As of February 24, 2017, a total of 13 (54%) of 24 states reporting provisional data detected at least 32 aquatic facility-associated cryptosporidiosis outbreaks in 2016. In comparison, 20 such outbreaks were voluntarily reported to CDC via the National Outbreak Reporting System for 2011, 16 for 2012, 13 for 2013, and 16 for 2014. This report highlights cryptosporidiosis outbreaks associated with aquatic facilities in three states (Alabama, Arizona, and Ohio) in 2016. This report also illustrates the use of CryptoNet, the first U.S. molecularly based surveillance system for a parasitic disease, to further elucidate Cryptosporidium chains of transmission and cryptosporidiosis epidemiology. CryptoNet data can be used to optimize evidence-based prevention strategies. Not swimming when ill with diarrhea is key to preventing and controlling aquatic facility-associated cryptosporidiosis outbreaks (https://www.cdc.gov/healthywater/swimming/swimmers/steps-healthy-swimming.html). |
Volumetric measurement of rock movement using photogrammetry
Benton DJ , Iverson SR , Martin LA , Johnson JC , Raffaldi MJ . Int J Min Sci Technol 2015 26 (1) 123-130 NIOSH ground control safety research program at Spokane, Washington, is exploring applications of photogrammetry to rock mass and support monitoring. This paper describes two ways photogrammetric techniques are being used. First, photogrammetric data of laboratory testing is being used to correlate energy input and support deformation. This information can be used to infer remaining support toughness after ground deformation events. This technique is also demonstrated in a field application. Second, field photogrammetric data is compared to crackmeter data from a deep underground mine. Accuracies were found to average 8. mm, but have produced results within 0.2. mm of true displacement, as measured by crackmeters. Application of these techniques consists of monitoring overall fault activity by monitoring multiple points around the crackmeter. A case study is provided in which a crackmeter is clearly shown to have provided insufficient information regarding overall fault ground deformation. Photogrammetry is proving to be a useful ground monitoring tool due to its unobtrusiveness and ease of use. |
Prepregnancy obesity and primary cesareans among otherwise low-risk mothers in 38 U.S. states in 2012
Declercq E , MacDorman M , Osterman M , Belanoff C , Iverson R . Birth 2015 42 (4) 309-18 BACKGROUND: The United States has recently experienced increases in both its rate of obesity and its cesarean rate. Our objective was to use a new item measuring prepregnancy body mass index (BMI) on the U.S. Standard Certificate of Live Birth to examine at a population level the relationship between maternal obesity and primary cesarean delivery for women at otherwise low risk for cesarean delivery. METHODS: By 2012, 38 states with 86 percent of United States births had adopted the U.S. Standard Certificate. The sample was limited to the 2,233,144 women who had a singleton, vertex, term (37-41 weeks) birth in 2012 and no prior cesarean. We modeled the likelihood of a primary cesarean by BMI category, controlling for maternal socio-demographic and medical characteristics. RESULTS: Overall, 46.4 percent of otherwise low-risk mothers had a prepregnancy BMI in the overweight (25.1%) or obese (21.3%) categories, with the obese category distributed as follows: obese I (BMI 30.0-34.9, 12.4%); obese II (BMI 35.0-39.9, 5.5%); and obese III (BMI 40+, 3.5%). Obesity rates were highest among American Indian and Alaska Native (32.5%) and non-Hispanic black mothers (30.5%). After adjustment for demographic and medical risks, the adjusted risk ratios (95% confidence intervals) of cesarean for low-risk primiparas were: 1.61 (1.60-1.63) for obese I, 1.86 (1.83-1.88) for obese II, and 2.21 (2.18-2.25) for obese III mothers compared with mothers in the normal weight category. DISCUSSION: A relationship between prepregnancy obesity and primary cesarean delivery among relatively low-risk mothers remained even after controlling for social and medical risk factors. |
Modelling blast induced damage from a fully coupled explosive charge
Onederra IA , Furtney JK , Sellers E , Iverson S . Int J Rock Mech Min Sci 2013 58 73-84 This paper presents one of the latest developments in the blasting engineering modelling field the Hybrid Stress Blasting Model (HSBM). HSBM includes a rock breakage engine to model detonation, wave propagation, rock fragmentation, and muck pile formation. Results from two controlled blasting experiments were used to evaluate the code's ability to predict the extent of damage. Results indicate that the code is capable of adequately predicting both the extent and shape of the damage zone associated with the influence of point-of-initiation and free-face boundary conditions. Radial fractures extending towards a free face are apparent in the modelling output and matched those mapped after the experiment. In the stage 2 validation experiment, the maximum extent of visible damage was of the order of 1.45 m for the fully coupled 38-mm emulsion charge. Peak radial velocities were predicted within a relative difference of only 1.59% at the nearest history point at 0.3 m from the explosive charge. Discrepancies were larger further away from the charge, with relative differences of -22.4% and -42.9% at distances of 0.46 m and 0.61 m, respectively, meaning that the model overestimated particle velocities at these distances. This attenuation deficiency in the modelling produced an overestimation of the damage zone at the corner of the block due to excessive stress reflections. The extent of visible damage in the immediate vicinity of the blasthole adequately matched the measurements. (C) 2012 Elsevier Ltd. All rights reserved. |
The National Amyotrophic Lateral Sclerosis (ALS) registry
Antao VC , Horton DK . J Environ Health 2012 75 (1) 28-30 A myotrophic lateral sclerosis (ALS) is a progressive and often fatal neuromuscular disease. Most people die within 2–5 years of being diagnosed with ALS (Mitsumoto, Chad, & Pioro, 1998). Community concerns about perceived clusters of cases of ALS have challenged public health agencies to consider the possible contribution of environmental contaminants to the development of this disease. The general categories of possible environmental risk factors that have been investigated include heavy metals, trace elements, solvents and other volatile organic chemicals, ionizing and non-ionizing radiation, and agricultural chemicals. | Several investigations have been conducted of heavy metal exposure, particularly lead, as a risk factor for ALS. Some case-control studies demonstrated a positive association between past exposure to lead and risk of ALS (Armon, Kurland, Daube, & O’Brien, 1991; Kamel et al., 2002; Roelofs-Iverson, Mulder, Elveback, Kurland, & Molgaard, 1984). Also, the epidemiologic literature offers some support for an association between ALS and past exposure to organic solvents (Gunnarsson, Lindberg, Söderfeldt, & Axelson, 1991; McGuire et al., 1997). | In addition, certain occupations, such as military work, have been listed as a risk factor for ALS (Nicholas et al., 1998; Schulte, Burnett, Boeniger, & Johnson, 1996; Sutedja et al., 2009; Weisskopf et al., 2005). Several other potential risk factors have been evaluated in the scientific literature including infectious agents (Fang et al., 2011), nutritional intake (Okamoto, Kihira, Kobashi et al., 2009; Wang et al., 2011; Woolsey, 2008), physical activity, and trauma (Beghi et al., 2010; Okamoto, Kihira, Kondo et al., 2009; Piazza, Siren, & Ehrenreich, 2004; Strickland, Smith, Dolliff, Goldman, & Roelofs, 1996). | The uncertainty about the incidence and prevalence of ALS, as well as the lack of knowledge about the role of environmental exposures in the etiology of ALS, has created a need for structured data collection. In 2008, President Bush signed the ALS Registry Act into law, allowing the Agency for Toxic Substances and Disease Registry (ATSDR) to create the National ALS Registry. The purpose of the registry is to quantify the incidence and prevalence of ALS in the U.S., describe the demographics of persons with ALS, and examine risk factors for the disease. |
Recognition and diagnosis of Cryptococcus gattii infections in the United States
Iverson SA , Chiller T , Beekmann S , Polgreen PM , Harris J . Emerg Infect Dis 2012 18 (6) 1012-5 TO THE EDITOR: An outbreak of Cryptococcus gattii cryptococcosis has been ongoing in the US Pacific Northwest (PNW) since 1999. In contrast to C. neoformans infections, which typically cause meningitis in HIV-infected persons, outbreak-associated C. gattii infections occur primarily in persons without HIV and often cause pneumonia. Sporadic, nonoutbreak-associated C. gattii infections often cause meningitis and have been reported outside the PNW. The prevalence of both types of C. gattii infection in the United States is unknown because diagnostic practices and awareness vary among physicians. |
Serological response to Bartonella species in febrile patients from Nepal
Myint KS , Gibbons RV , Iverson J , Shrestha SK , Pavlin JA , Mongkolsirichaikul D , Kosoy MY . Trans R Soc Trop Med Hyg 2011 105 (12) 740-2 The Bartonella-associated illnesses are spread world-wide and involve a broad spectrum of signs and symptoms in humans. Several Bartonella species have been shown to be responsible for cases of febrile illnesses. Little information exists on distribution of Bartonella species and their role in human diseases in Nepal. Our preliminary study, a retrospective serological survey of archived specimens, suggests that Bartonella antibodies are prevalent among febrile patients in the Kathmandu Valley of Nepal. |
Combining culture techniques for Bartonella: the best of both worlds
Lynch T , Iverson J , Kosoy M . J Clin Microbiol 2011 49 (4) 1363-8 In this study we compared some common Bartonella culturing methodologies using four diverse species causing human illnesses. Based on a review of the literature, we focused on three major inconsistencies between protocols: base media, cell co-culture and temperature. Our data showed that B. tamiae demonstrated temperature-dependent growth limitations between common culturing conditions only 2 degrees C apart. Additionally, growth of B. quintana was significantly enhanced by the presence of mammalian cell co-culture within mammalian culture conditions, however when the media was modified to incorporate insect culture-based media, co-culturing with mammalian cells was no longer needed. In this study, we were able to overcome these temperature and cell dependent limitations and accommodate all of the strains tested by combining mammalian culture-based media with insect culture-based media. |
Acute arboviral infections in Guinea, West Africa, 2006
Jentes ES , Robinson J , Johnson BW , Conde I , Sakouvougui Y , Iverson J , Beecher S , Bah MA , Diakite F , Coulibaly M , Bausch DG . Am J Trop Med Hyg 2010 83 (2) 388-94 Acute febrile illnesses comprise the majority of the human disease burden in sub-Saharan Africa. We hypothesized that arboviruses comprised a considerable proportion of undiagnosed febrile illnesses in Guinea and sought to determine the frequency of arboviral disease in two hospitals there. Using a standard case definition, 47 suspected cases were detected in approximately 4 months. Immunoglobulin M antibody capture enzyme-linked immunosorbent assays and plaque-reduction neutralization assays revealed that 63% (30/47) of patients were infected with arboviruses, including 11 West Nile, 2 yellow fever, 1 dengue, 8 chikungunya, and 5 Tahyna infections. Except for yellow fever, these are the first reported cases of human disease from these viruses in Guinea and the first reported cases of symptomatic Tahyna infection in Africa. These results strongly suggest that arboviruses circulate and are common causes of disease in Guinea. Improving surveillance and laboratory capacity for arbovirus diagnoses will be integral to understanding the burden posed by these agents in the region. |
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