Last data update: Dec 02, 2024. (Total: 48272 publications since 2009)
Records 1-30 (of 274 Records) |
Query Trace: Fisher H H[original query] |
---|
Coccidioidomycosis transmission through solid organ transplantation (2013-2022): A report of the Organ Procurement and Transplantation Network ad hoc Disease Transmission Advisory Committee
Lee DH , Abidi MZ , Fisher C , Hughart AL , Toda M , Williams S , Berry GJ , Graves R , Handarova D , Ho CS , Kittleson M , Levi ME , Livelli T , Marboe CC , Annamabhotla P , Miller RA , Sharma T , Sellers MT , Taimur S , Te HS , Trindade AJ , Wood RP , Zaffiri L , Pouch SM , Danziger-Isakov L . Transpl Infect Dis 2024 e14406 BACKGROUND: Coccidioidomycosis is a fungal infection that poses a serious risk when transmitted through organ transplantation. We analyzed cases reported to the Organ Procurement and Transplantation Network ad hoc Disease Transmission Advisory Committee from 2013 to 2022. METHODS: Donors and/or recipients who had positive Coccidioides immitis/posadasii serology, pathology, and/or culture were included in this study. Cases adjudicated as 'proven' or 'probable' were analyzed for donor infection risk factors, the timing of infection, transmission by organ type, clinical manifestations, and recipient outcomes. Patient and facility identifiers were removed prior to review. RESULTS: During this time period, 73 potential instances of Coccidioides donor disease transmission events were reported. Among them, infection was transmitted from seven deceased donors to eight recipients. All seven deceased donors had prior infection or exposure to regions where coccidioidomycosis is endemic. Of 20 individuals receiving organs from these donors, eight developed infection, resulting in a 40% transmission rate. The median time to diagnosis post-transplant was 39 days. Disseminated disease occurred in six recipients, five of whom died from the infection. Notably, none of the recipients who received prophylactic antifungal treatment died from the infection. CONCLUSION: Despite its rarity, donor-derived Coccidioides infection is a serious concern, particularly due to the high mortality rate in the early post-transplant period. To mitigate these risks, a thorough assessment of donor exposure history, coupled with donor serology and bronchoalveolar lavage cultures, can effectively guide post-transplant antifungal prophylaxis. Prompt reporting is crucial to prevent Coccidioides infections among other recipients. |
Respiratory viruses associated with severe acute respiratory infection in children aged <5 years at a tertiary care hospital in Delhi, India during 2013-15
Aneja S , Singh V , Narayan VV , Gohain M , Choudekar A , Gaur B , DeBord KR , Whitaker B , Krishnan A , Broor S , Saha S , Iuliano AD . J Glob Health 2024 14 04230 BACKGROUND: With the increased availability of licensed vaccines for respiratory viruses such as severe acute respiratory syndrome coronavirus 2, respiratory syncytial virus (RSV), and influenza virus, a better understanding of the viral aetiology of severe acute respiratory infections (SARI) among children could help in optimising the use of these vaccines. We conducted a study among children aged <5 years hospitalised with SARI at a tertiary care children's hospital in north India and tested for common respiratory pathogens. METHODS: We randomly enrolled eligible SARI cases aged <5 years from August 2013 to July 2015. SARI cases were defined as either <7-day history of fever with cough or in children aged eight days to three months, a physician diagnosis of acute lower respiratory infection requiring hospitalisation. We also enrolled an age-group matched control without any acute illness in a 2:1 ratio from the outpatient clinic within 24 hours of case enrolment. Nasopharyngeal and/or oropharyngeal swabs were collected and tested using TaqMan Array Cards, a real-time reverse transcription polymerase chain reaction-based multi-pathogen testing platform for selected respiratory viruses among the enrolled cases and controls. We compared the prevalence of each pathogen among cases and controls using the χ(2) (χ(2)) or Fisher exact test (P < 0.05). We used logistic regression to estimate adjusted odds ratios (aORs) which were then used to calculate aetiologic fractions (EFs). RESULTS: We enrolled 840 cases and 419 outpatient controls. Almost half of the individuals in the whole sample were aged <6 months (n = 521, 41.4%). Females made up 33.7% of cases and 37.2% of controls. Viral detections were more common among cases (69%, 95% confidence interval (CI) = 66, 73) compared to controls (33%; 95% CI = 29, 38) (P < 0.01). RSV (n = 257, 31%; 95% CI = 28, 34%) was the most common virus detected among cases. Influenza A was detected among 24 (3%; 95% CI = 2, 4%), and influenza B among 5 (1%; 95% CI = 0, 1%) cases. The association between the virus and SARI was strongest for RSV (aOR = 23; 95% CI = 12, 47; EF = 96%). Antivirals were administered to 1% of SARI cases while 78% received antibiotics. CONCLUSIONS: Using a multi-pathogen molecular detection method, we detected respiratory viruses among more than two-thirds of children aged <5 years admitted with SARI in the Delhi tertiary care children's hospital. The guidelines for preventing and managing SARI cases among children could be optimised further with the improved availability of antivirals and vaccines. |
Transition to enteral triazole antifungal therapy for pediatric invasive candidiasis: Secondary analysis of a multicenter cohort study conducted by the Pediatric Fungal Network
Bucayu RFT , Boge CLK , Yildirim I , Avilés-Robles M , Vora SB , Berman DM , Sharma TS , Sung L , Castagnola E , Palazzi DL , Danziger-Isakov L , Yin DE , Roilides E , Maron G , Tribble AC , Soler-Palacin P , López-Medina E , Romero J , Belani K , Arrieta AC , Carlesse F , Nolt D , Halasa N , Dulek D , Rajan S , Muller WJ , Ardura MI , Pong A , Gonzalez BE , Salvatore CM , Huppler AR , Aftandilian C , Abzug MJ , Chakrabarti A , Green M , Lutsar I , Knackstedt ED , Johnson SK , Steinbach WJ , Fisher BT , Wattier RL . J Pediatric Infect Dis Soc 2024 Of 319 children with invasive candidiasis, 67 (21%) transitioned from intravenous to enteral antifungal therapy. Eight (12%) transitioned back to intravenous antifungal therapy, one due to perceived treatment failure defined by clinical progression or worsening. Global treatment response at study completion was success in 66 participants transitioned to enteral therapy. |
Structure-based design of glycoprotein subunit vaccines for mumps
Loomis RJ , Lai YT , Sowers SB , Fisher B , Derrien-Colemyn A , Ambrozak DR , Tsybovsky Y , Crooke SN , Latner DR , Kong WP , Ruckwardt TJ , Plotkin SA , Kwong PD , Mascola JR , Graham BS , Hickman CJ , Stewart-Jones GBE . Proc Natl Acad Sci U S A 2024 121 (47) e2404053121 Mumps virus (MuV) is a highly contagious paramyxovirus that is endemic in most regions of the world and continues to cause outbreaks even in highly immunized populations. Outbreaks of mumps in countries with high measles, mumps, and rubella vaccination coverage have been attributed to waning immunity and antigenic differences between the Jeryl Lynn vaccine strain (genotype A) and circulating wild-type viruses. To obtain a subunit vaccine, we used structure-based design to engineer the mumps fusion (F) glycoprotein stabilized in its prefusion conformation (Pre-F) as well as a chimeric immunogen comprising Pre-F linked to mumps hemagglutinin neuraminidase (HN); in mice, both Pre-F antigen and the chimeric antigen elicited potent cross-reactive plaque reducing neutralizing titers to genotypes A, G, and H mumps. A crystal structure of mumps Pre-F at 2.16 Å resolution validated the stabilization strategy, while a post-fusion form of F was engineered as a comparator. Monoclonal antibodies to mumps Pre-F and HN were isolated from immunized mice; 7 of 14 Pre-F-specific antibodies and 9 of 15 HN-specific antibodies were capable of neutralizing genotype G MuV with a range of potencies. Additionally, 7 of 14 Pre-F-specific antibodies neutralized genotype A mumps. Structural and binding analyses of Pre-F-specific antibodies revealed binding to four discrete neutralizing antigenic sites and binding analyses of HN-specific antibodies revealed binding to five discrete neutralizing antigenic sites. Overall, the PreF and the chimeric Pre-F/HN immunogens are promising candidates to boost MMR-elicited immunity to mumps or as a next-generation vaccine. |
Heartland virus infection in elderly patient initially suspected of having ehrlichiosis, North Carolina, USA
Barbarin AM , Fisher TG , Reiskind MH , Williams C , Ayres BN , Burkhalter KL , Nicholson WL . Emerg Infect Dis 2024 30 (12) We report a patient in North Carolina, USA, with Heartland virus infection whose diagnosis was complicated by previous Ehrlichia chaffeensis infection. We identified E. ewingii-infected and Bourbon virus-infected tick pools at the patient's residence. Healthcare providers should consider testing for tickborne viruses if ehrlichiosis is suspected. |
Influenza A virus within-host evolution and positive selection in a densely sampled household cohort over three seasons
Bendall EE , Zhu Y , Fitzsimmons WJ , Rolfes M , Mellis A , Halasa N , Martin ET , Grijalva CG , Talbot HK , Lauring AS . Virus Evol 2024 10 (1) veae084 While influenza A virus (IAV) antigenic drift has been documented globally, in experimental animal infections, and in immunocompromised hosts, positive selection has generally not been detected in acute infections. This is likely due to challenges in distinguishing selected rare mutations from sequencing error, a reliance on cross-sectional sampling, and/or the lack of formal tests of selection for individual sites. Here, we sequenced IAV populations from 346 serial, daily nasal swabs from 143 individuals collected over three influenza seasons in a household cohort. Viruses were sequenced in duplicate, and intrahost single nucleotide variants (iSNVs) were identified at a 0.5% frequency threshold. Within-host populations exhibited low diversity, with >75% mutations present at <2% frequency. Children (0-5 years) had marginally higher within-host evolutionary rates than adolescents (6-18 years) and adults (>18 years, 4.4 × 10(-6) vs. 9.42 × 10(-7) and 3.45 × 10(-6), P < .001). Forty-five iSNVs had evidence of parallel evolution but were not over-represented in HA and NA. Several increased from minority to consensus level, with strong linkage among iSNVs across segments. A Wright-Fisher approximate Bayesian computational model identified positive selection at 23/256 loci (9%) in A(H3N2) specimens and 19/176 loci (11%) in A(H1N1)pdm09 specimens, and these were infrequently found in circulation. Overall, we found that within-host IAV populations were subject to genetic drift and purifying selection, with only subtle differences across seasons, subtypes, and age strata. Positive selection was rare and inconsistently detected. |
N95 filtering facepiece respirator reuse, extended use, and filtration efficiency
Wang RC , Addo N , Degesys NF , Fahimi J , Ford JS , Rosenthal E , Harris AR , Yaffee AQ , Peterson S , Rothmann RE , DeAngelis J , Tolia V , Shah MN , Stephenson TB , Nogueira-Prewitt SJ , Yoon KN , Fisher EM , Raven MC . JAMA Netw Open 2024 7 (10) e2441663 This cohort study examines the association of reuse of N95 filtering facepiece respirators and N95 filtration efficiency. | eng |
"But then that's another barrier": A qualitative study of parent and provider perspectives on rural versus urban disparities in adolescent vaccination
Brewer SE , Cataldi JR , Perreira C , Nederveld A , Fisher MP , Furniss A , Williams C , O'Leary ST , Dempsey AF . Vaccine 2024 42 (26) 126456 PURPOSE: Vaccination rates are significantly lower among adolescents living in rural areas compared to those living in urban areas. The objective of this study was to understand the factors contributing to disparities in vaccination between adolescents in rural compared to urban areas. METHODS: Semi-structured qualitative interviews were conducted with parents and providers in 16 rural and 4 urban counties of Colorado. Interview questions followed the socioecological model of health and addressed personal, interpersonal, community, and environment/structural barriers and facilitators that impact adolescent vaccination rates. Qualitative content analysis with a directed content analysis approach was used. Urban and rural interviews were compared to identify barriers unique to rural communities. FINDINGS: Reported barriers included lack of vaccine access at primary care, lack of routine preventive care utilization, the need to take off time from work and school, and misinformation about vaccines. Barriers that were unique to rural communities included structural barriers such as lack of evening and weekend appointments, providers not stocking vaccines, short provider tenures, and costs; logistical barriers such as the need for multiple visits to multiple locations and distance and travel time; and beliefs and behaviors such as an overreliance on sports physicals (in lieu of preventive visits) and natural lifestyle cultures. CONCLUSIONS: There are unique challenges to adolescent vaccination in rural areas that contribute to fewer adolescents receiving their recommended vaccines. Addressing structural barriers may address this disparity. |
Risk of clade II mpox associated with intimate and nonintimate close contact among men who have sex with men and transgender adults - United States, August 2022-July 2023
Chard AN , Dalton AF , Diallo AO , Moulia DL , Deputy NP , Zecca IB , Quilter LAS , Kachur RE , McCollum AM , Rowlands JV , Britton AN , Fisher R , Chai SJ , Licherdell E , Still WL , Morris AL , Castilho JL , Markus TM , Morrow AS , Danza P , Hansen AP , Ali SI , Wegner CW , Weber R , Betancourt GS , Zipprich J , Sutton M , Pathela P , Hawkins S , Wendel KA , Feldstein LR . MMWR Morb Mortal Wkly Rep 2024 73 (40) 896-902 A global outbreak of clade II mpox associated with sexual contact, disproportionately affecting gay, bisexual, and other men who have sex with men (MSM), has been ongoing since May 2022. Information on types of contact most associated with transmission is limited. This report used data from a multijurisdictional vaccine effectiveness case-control study of sexually active persons aged 18-49 years who identified as MSM or transgender, collected during August 2022-July 2023. Odds of mpox associated with selected types of intimate and nonintimate close contact with a person with mpox were estimated. Among 457 case-patients and 1,030 control patients who met minimum data requirements, 150 (32.8%) case-patients and 57 (5.5%) control patients reported close contact with a person with mpox and were included in this analysis. Adjusted odds of mpox were 5.4 times as high among those who reported having condomless receptive anal sex with a person with mpox, compared with participants who reported close contact with a person with mpox and no condomless receptive anal sex with that person (OR = 5.4; p = 0.031). Although the mpox vaccine is highly effective, vaccination coverage remains low; a multifaceted approach to prevention remains important and should include vaccination promotion, safer sex practices, and increasing awareness that mpox continues to circulate. |
Total outward leakage of face-worn products used by the general public for source control
Yang W , Myers W , Bergman M , Fisher E , Ryan KJ , Vollmer B , Portnoff L , Zhuang Z . Am J Infect Control 2024 BACKGROUND: During COVID-19 pandemic, the general public used any face-worn products they could get to overcome the shortage of N95 respirators and surgical masks. These products, often not meeting any standards, raised concerns about their effectiveness in reducing the spread of respiratory viruses. METHODS: This study quantified total outward leakage (TOL) of units from nine face-worn product categories used by members of the general public. A benchtop system was devised to test two units from each category on two different-sized headforms with silicone elastomer skin. Each unit was donned five times per headform. RESULTS: Both face-worn product category and headform size significantly affected TOL (P-Value <0.05). The TOL of tested face-worn products varied from 10% to 58% depending on both model and headform size. Face-worn products donned on the medium headform had a higher mean TOL compared to those donned on the larger headform. CONCLUSIONS: Overall, single-layer cloth masks are the least effective measure for source control due to their highest TOL among the tested face-worn products. Three-layer disposable face masks may be a favorable option for source control among the public. A standard should be developed for face-worn product design and manufacturing to accommodate different facial sizes. |
Regulatory elements in SEM1-DLX5-DLX6 (7q21.3) locus contribute to genetic control of coronal nonsyndromic craniosynostosis and bone density-related traits
Nicoletti P , Zafer S , Matok L , Irron I , Patrick M , Haklai R , Evangelista JE , Marino GB , Ma'ayan A , Sewda A , Holmes G , Britton SR , Lee WJ , Wu M , Ru Y , Arnaud E , Botto L , Brody LC , Byren JC , Caggana M , Carmichael SL , Cilliers D , Conway K , Crawford K , Cuellar A , Di Rocco F , Engel M , Fearon J , Feldkamp ML , Finnell R , Fisher S , Freudlsperger C , Garcia-Fructuoso G , Hagge R , Heuzé Y , Harshbarger RJ , Hobbs C , Howley M , Jenkins MM , Johnson D , Justice CM , Kane A , Kay D , Gosain AK , Langlois P , Legal-Mallet L , Lin AE , Mills JL , Morton JEV , Noons P , Olshan A , Persing J , Phipps JM , Redett R , Reefhuis J , Rizk E , Samson TD , Shaw GM , Sicko R , Smith N , Staffenberg D , Stoler J , Sweeney E , Taub PJ , Timberlake AT , Topczewska J , Wall SA , Wilson AF , Wilson LC , Boyadjiev SA , Wilkie AOM , Richtsmeier JT , Jabs EW , Romitti PA , Karasik D , Birnbaum RY , Peter I . Genet Med Open 2024 2 PURPOSE: The etiopathogenesis of coronal nonsyndromic craniosynostosis (cNCS), a congenital condition defined by premature fusion of 1 or both coronal sutures, remains largely unknown. METHODS: We conducted the largest genome-wide association study of cNCS followed by replication, fine mapping, and functional validation of the most significant region using zebrafish animal model. RESULTS: Genome-wide association study identified 6 independent genome-wide-significant risk alleles, 4 on chromosome 7q21.3 SEM1-DLX5-DLX6 locus, and their combination conferred over 7-fold increased risk of cNCS. The top variants were replicated in an independent cohort and showed pleiotropic effects on brain and facial morphology and bone mineral density. Fine mapping of 7q21.3 identified a craniofacial transcriptional enhancer (eDlx36) within the linkage region of the top variant (rs4727341; odds ratio [95% confidence interval], 0.48[0.39-0.59]; P = 1.2E-12) that was located in SEM1 intron and enriched in 4 rare risk variants. In zebrafish, the activity of the transfected human eDlx36 enhancer was observed in the frontonasal prominence and calvaria during skull development and was reduced when the 4 rare risk variants were introduced into the sequence. CONCLUSION: Our findings support a polygenic nature of cNCS risk and functional role of craniofacial enhancers in cNCS susceptibility with potential broader implications for bone health. |
Survival of children with critical congenital heart defects in the National Birth Defects Prevention Study
Forestieri NE , Olshan AF , Oster ME , Ailes EC , Fundora MP , Fisher SC , Shumate C , Romitti PA , FLiberman R , Nembhard WN , Carmichael SL , Desrosiers TA . Birth Defects Res 2024 116 (9) e2394 BACKGROUND: Critical congenital heart defects (CCHDs) are associated with considerable morbidity and mortality. This study estimated survival of children with nonsyndromic CCHDs and evaluated relationships between exposures of interest and survival by CCHD severity (univentricular or biventricular function). METHODS: This analysis included 4380 infants with CCHDs (cases) born during 1999-2011 and enrolled in the National Birth Defects Prevention Study, a multisite, population-based case-control study of major birth defects. Cases were linked to state death files. Nonparametric Kaplan-Meier survival functions were used to estimate 1- and 5-year survival probabilities overall and by severity group (univentricular/biventricular) stratified by demographic and clinical exposure variables of interest. The log-rank test was used to determine whether stratified survival curves were equivalent. Survival and 95% confidence intervals (CIs) were also estimated using Cox proportional hazards modeling adjusted for maternal age, education, race/ethnicity, study site, and birth year. RESULTS: One- and five-year survival rates were 85.8% (CI 84.7-86.8) and 83.7% (CI 82.5-84.9), respectively. Univentricular 5-year survival was lower than biventricular case survival [65.3% (CI 61.7-68.5) vs. 89.0% (CI 87.8-90.1; p < 0.001)]. Clinical factors (e.g. preterm birth, low birthweight, and complex/multiple defects) were associated with lower survival in each severity group. Sociodemographic factors (non-Hispanic Black race/ethnicity, <high school education, smoking, and lower household income) were only associated with survival among biventricular cases. CONCLUSIONS: Mortality among children with CCHDs occurred primarily in the first year of life. Survival was lower for those with univentricular defects, and social determinants of health were most important in predicting survival for those with biventricular defects. |
Public willingness to mask and vaccinate in the future: Results from a 2023 nationally representative survey of US adults
SteelFisher GK , Findling MG , Caporello HL , Stein RI , Lubell KM , Fisher AM , Lane LA , Boyea A , Espino L , Sutton J . Health Secur 2024 22 (4) 311-323 The enduring spread of COVID-19 and other respiratory viruses highlights a need for greater focus on long-term public willingness to perform protective behaviors. Although COVID-19 is no longer considered a public health emergency of international concern, it is unknown whether people in the United States plan to continue protective behaviors to protect themselves and others against infection. To inform planning and communications, we used a nationally representative survey of 1,936 US adults to examine attitudes and intentions toward future vaccination and mask-wearing. A majority believed COVID-19 vaccines were safe (73%) and effective in protecting against serious illness (72%). One-third (33%) had strong intentions to get an updated COVID-19 vaccine most years in the future. Among those with weaker intentions (n=1,287), many cited concerns about safety (71%) and efficacy (64%), lack of trust in institutions (64%), or beliefs that prior vaccination or infection protected them (62%). Approximately two-thirds (69%) of respondents believed masks were effective in protecting the wearer from getting COVID-19, and a majority appeared moderately receptive to future public mask-wearing, particularly when there was proximate risk of infection from COVID-19 (67%) or other respiratory viruses (59%). Men, non-Hispanic White adults, younger adults, rural residents, and adults with higher incomes, without college degrees, and without serious medical conditions or physical limitations were more likely to indicate resistance toward future COVID-19 vaccination and/or mask-wearing. Findings support tailored messaging to address concerns and opportunities among different populations, as well as support for communications programs and community engagement to motivate future uptake. |
Development of an experimental technique to determine the barrier performance of medical gloves when stretched
Soo JC , Portnoff L , Bickson J , Fisher EM . Ann Work Expo Health 2024 Protective clothing standards, such as test methods published by ASTM International, play an integral role in ensuring the performance of personal protective equipment. The standard tests are not without limitations and are periodically reviewed and often updated. Some tests may not be reflective of in-use conditions. A new test cell was designed using sanitary fixtures to evaluate the effect of glove stretch on barrier performance using fluorescein solution as the challenge agent for enhanced visualization and fluorometer detection. Domed-shaped and flat screens were developed to permit and limit glove stretch within the test cell. The barrier performance of glove swatches was evaluated for both stretched and unstretched states. Latex, nitrile, and vinyl glove models of various thicknesses were evaluated. The tests were conducted following pressure and time parameters specified in ASTM F903, ASTM F1670, and ASTM F1671. Fluorescein solution movement, which may occur through penetration, was measured using a fluorometer. Glove stretch caused a reduction in glove thickness ranging from 16% to 40%. Overall, 21 sample failures were found (16.7%; n = 126) regardless of test condition. Nitrile gloves provided better barrier efficacy with the lowest failure rates (2.38%; 1 failure out of 42) compared to latex (19.4%; 7 failures out of 36) and vinyl gloves (27.1%; 13 failures out of 48). Differences in failure rates between stretched and unstretched gloves were insignificant; however, the latex material showed a 2.5 times increase in failures when stretched compared to unstretched. The new test apparatus was able to differentiate between the barrier performance of different glove materials. The use of a domed screen allowed the gloves to stretch, a condition that better represents the state of gloves when in use. Analysis of samples collected from the glove surface opposite to the exposure may provide a way to assess chemical permeation in addition to penetration. |
Identifying a level of neutralizing antibody that correlates with protection from clinical mumps disease during a 2017 mumps outbreak among military service members
Sowers SB , Clemmons NS , Mercader S , Nielsen L , Colley H , Jordan NN , Bettger CC , Masters NB , Markelz AE , Hickman CJ . Open Forum Infect Dis 2024 11 (7) ofae329 BACKGROUND: In 2017, a mumps outbreak occurred in a US military barracks. Serum collected at service entry was used to compare pre-exposure with presumptive vaccine-induced antibody levels from persons who developed mumps (cases) and potentially exposed persons who did not develop mumps (non-cases). Sufficient information to determine levels of exposure during the outbreak was not available. METHODS: Pre-outbreak serum samples from the Department of Defense Serum Repository were available from 254 potentially exposed service members. Twelve developed clinical symptoms and had post-outbreak serum collected. All sera were tested with a mumps-specific enzyme immunoassay for immunoglobulin M, immunoglobulin G (IgG), and IgG avidity. The neutralizing antibodies to vaccine strain (Jeryl Lynn [JL], genotype A) and wildtype virus (genotype G) was assessed by a plaque reduction neutralization test. A Fisher exact test and receiver operator characteristic curve were used to analyze the antibody response for non-cases and mumps cases. RESULTS: Eight mumps cases were laboratory confirmed. Pre-outbreak neutralizing antibody titers to JL and genotype G mumps virus and pre-outbreak IgG index values were proportionately lower for most cases as compared with exposed non-cases. When compared with potentially exposed non-cases, cases with clinical symptoms had greater odds of having a pre-outbreak JL titer <41 and a genotype G titer <16. CONCLUSIONS: We identified potential correlates of protection for mumps neutralizing antibody titers against JL and genotype G mumps viruses. |
Successful distribution of tecovirimat during the peak of the mpox outbreak - Los Angeles County, June 2022-January 2023
O'Neil MJ , Archer R , Danza P , Fisher R , Bagwell DA , Younis I , Kulkarni S , Rubin Z , Kim M , Balter S , Terashita D , Kim J , Singhal R , Hancz D , Gausche-Hill M , Shah NK . MMWR Morb Mortal Wkly Rep 2024 73 (24) 546-550 Tecovirimat is the first-line antiviral treatment recommended for severe mpox or for persons with mpox who are at risk for severe disease; tecovirimat is available in the United States under an expanded access investigational new drug (IND) protocol. During the 2022-2023 mpox outbreak, local U.S. health jurisdictions facilitated access to tecovirimat. In June 2022, Los Angeles County (LAC) rapidly developed strategies for tecovirimat distribution using existing medical countermeasure distribution networks established by the Public Health Emergency Preparedness Program and the Hospital Preparedness Program, creating a hub and spoke distribution network consisting of 44 hub facilities serving 456 satellite sites across LAC. IND patient intake forms were analyzed to describe mpox patients treated with tecovirimat. Tecovirimat treatment data were matched with case surveillance data to calculate time from specimen collection to patients receiving tecovirimat. Among 2,281 patients with mpox in LAC, 735 (32%) received tecovirimat during June 2022-January 2023. Among treated patients, approximately two thirds (508; 69%) received treatment through community clinics and pharmacies. The median interval from specimen collection to treatment was 2 days (IQR = 0-5 days). Local data collection and analysis helped to minimize gaps in treatment access and facilitated network performance monitoring. During public health emergencies, medical countermeasures can be rapidly deployed across a large jurisdiction using existing distribution networks, including clinics and pharmacies. |
Viewpoint: Can qPCR replace the standard plaque assay in the ASTM F1671 to assess personal protective equipment barrier performance?
Di Giuseppe M , Fisher EM , Greenawald L , Pollard JP . Int J Cloth Sci Technol 2024 36 (3) 385-392 |
HIV self-test performance evaluation among priority populations in rural Mozambique: Results from a community-based observational study
De Schacht C , Lucas C , Paulo P , Naftal Fernando A , Ernesto Chinai J , Silva WP , Amane G , Sultane T , Honwana N , Malimane I , Couto A , Yu Z , Wester CW . PLoS One 2024 19 (6) e0305391 BACKGROUND: In 2021, Mozambique initiated community-based oral HIV self-testing (HIVST) to increase testing access and uptake among priority groups, including adult males, adolescents, and young adults. Within an HIVST pilot project, we conducted a performance evaluation assessing participants' ability to successfully conduct HIVST procedures and interpret results. METHODS: A cross-sectional study was performed between February-March 2021 among employees, students (18-24 years of age), and community members, using convenience sampling, in two rural districts of Zambézia Province, Mozambique. We quantified how well untrained users performed procedures for the oral HIVST (Oraquick®) through direct observation using a structured checklist, from which we calculated an HIVST usability index (scores ranging 0-100%). Additionally, participants interpreted three previously processed anonymous HIVST results. False reactive and false non-reactive interpretation results were presented as proportions. Bivariate analysis was conducted using Chi-square and Fisher exact tests. RESULTS: A total of 312 persons participated (131[42%] community members, 71[23%] students, 110[35%] employees); 239 (77%) were male; the mean age was 28 years (standard deviation 10). Average usability index scores were 80% among employees, 86% among students, and 77% among community members. Main procedural errors observed included "incorrect tube positioning" (49%), "incorrect specimen collection" (43%), and "improper waiting time for result interpretation" (42%). From the presented anonymous HIVST results, 75% (n = 234) correctly interpreted all three results, while 9 (3%) of study participants failed to correctly interpret any results. Overall, 36 (12%) gave a false non-reactive result interpretation, 21 (7%) a false reactive result interpretation, and 14 (4%) gave both false non-reactive and false reactive result interpretations. Community members generally had lower performance. CONCLUSIONS: Despite some observed testing procedural errors, most users could successfully perform an HIVST. Educational sessions at strategic places (e.g., schools, workplaces), and support via social media and hotlines, may improve HIVST performance quality, reducing the risk of incorrect interpretation. |
Assessment of glove stretch and storage temperature on fentanyl permeation: Implications for standard test methods and PPE recommendations
Fisher EM , Streeter RT , Hofacre KC , Greenawald LA , Yoon NK , Soo JC , Keyes PH . J Occup Environ Hyg 2024 1-10 The National Institute for Occupational Safety and Health recommends the use of nitrile gloves with a minimum thickness of 5.0 ± 2.0 mil [0.127 ± 0.051 millimeters] in situations where it is suspected or known that fentanyl or other illicit drugs are present. However, there is limited data available on fentanyl permeation through gloves. Current test methods used to measure fentanyl permeation do not consider the effect of glove fit and flexion. Furthermore, first responders need to have PPE readily available in the field, and storage conditions may affect the protective performance of the gloves. The objective of this study was to evaluate the effects of glove stretch and storage temperatures on glove durability and barrier performance against fentanyl. Nine nitrile glove models previously shown to be resistant to fentanyl permeation were selected for this investigation. These nine models were stretched 25% in one linear direction, to consider glove fit and flexion, and tested against fentanyl hydrochloride permeation. Additionally, four of the nine glove models were stored at 48 °C, 22 °C, and -20 °C, and evaluated for tensile strength, ultimate elongation, and puncture resistance after up to 16 wk of storage and fentanyl permeation after up to 8 wk of storage. At least one sample for six of the nine tested models had maximum permeation over the test method fail threshold when stretched. The tested storage temperatures showed no effect on glove tensile strength, ultimate elongation, and puncture resistance. The findings of this study can be used to inform PPE recommendations, with consideration to storage practices and proper sizing for first responders with potential exposure to fentanyl and other illicit drugs. The results of this study can be used to assess the need for new standard test methods to evaluate the barrier performance of gloves and shelf-life determination with consideration to glove fit. |
Literature review of pathogen agnostic molecular testing of clinical specimens from difficult-to-diagnose patients: Implications for public health
Downie DL , Rao P , David-Ferdon C , Courtney S , Lee JS , Kugley S , MacDonald PDM , Barnes K , Fisher S , Andreadis JL , Chaitram J , Mauldin MR , Salerno RM , Schiffer J , Gundlapalli AV . Health Secur 2024 To better identify emerging or reemerging pathogens in patients with difficult-to-diagnose infections, it is important to improve access to advanced molecular testing methods. This is particularly relevant for cases where conventional microbiologic testing has been unable to detect the pathogen and the patient's specimens test negative. To assess the availability and utility of such testing for human clinical specimens, a literature review of published biomedical literature was conducted. From a corpus of more than 4,000 articles, a set of 34 reports was reviewed in detail for data on where the testing was being performed, types of clinical specimens tested, pathogen agnostic techniques and methods used, and results in terms of potential pathogens identified. This review assessed the frequency of advanced molecular testing, such as metagenomic next generation sequencing that has been applied to clinical specimens for supporting clinicians in caring for difficult-to-diagnose patients. Specimen types tested were from cerebrospinal fluid, respiratory secretions, and other body tissues and fluids. Publications included case reports and series, and there were several that involved clinical trials, surveillance studies, research programs, or outbreak situations. Testing identified both known human pathogens (sometimes in new sites) and previously unknown human pathogens. During this review, there were no apparent coordinated efforts identified to develop regional or national reports on emerging or reemerging pathogens. Therefore, development of a coordinated sentinel surveillance system that applies advanced molecular methods to clinical specimens which are negative by conventional microbiological diagnostic testing would provide a foundation for systematic characterization of emerging and underdiagnosed pathogens and contribute to national biodefense strategy goals. |
Surveillance for emerging and reemerging pathogens using pathogen agnostic metagenomic sequencing in the United States: A critical role for federal government agencies
Downie DL , Rao P , David-Ferdon C , Courtney S , Lee JS , Quiner C , MacDonald PDM , Barnes K , Fisher S , Andreadis JL , Chaitram J , Mauldin MR , Salerno RM , Schiffer J , Gundlapalli AV . Health Secur 2024 The surveillance and identification of emerging, reemerging, and unknown infectious disease pathogens is essential to national public health preparedness and relies on fluidity, coordination, and interconnectivity between public and private pathogen surveillance systems and networks. Developing a national sentinel surveillance network with existing resources and infrastructure could increase efficiency, accelerate the identification of emerging public health threats, and support coordinated intervention strategies that reduce morbidity and mortality. However, implementing and sustaining programs to detect emerging and reemerging pathogens in humans using advanced molecular methods, such as metagenomic sequencing, requires making large investments in testing equipment and developing networks of clinicians, laboratory scientists, and bioinformaticians. In this study, we sought to gain an understanding of how federal government agencies currently support such pathogen agnostic testing of human specimens in the United States. We conducted a landscape analysis of federal agency websites for publicly accessible information on the availability and type of pathogen agnostic testing and details on flow of clinical specimens and data. The website analysis was supplemented by an expert review of results with representatives from the federal agencies. Operating divisions within the US Department of Health and Human Services and the US Department of Veterans Affairs have developed and sustained extensive clinical and research networks to obtain patient specimens and perform metagenomic sequencing. Metagenomic facilities supported by US agencies were not equally geographically distributed across the United States. Although many entities have work dedicated to metagenomics and/or support emerging infectious disease surveillance specimen collection, there was minimal formal collaboration across agencies. |
Birth prevalence of sickle cell disease and county-level social vulnerability - sickle cell data collection program, 11 States, 2016-2020
Kayle M , Blewer AL , Pan W , Rothman JA , Polick CS , Rivenbark J , Fisher E , Reyes C , Strouse JJ , Weeks S , Desai JR , Snyder AB , Zhou M , Sutaria A , Valle J , Horiuchi SS , Sontag MK , Miller JI , Singh A , Dasgupta M , Janson IA , Galadanci N , Reeves SL , Latta K , Hurden I , Cromartie SJ , Plaxco AP , Mukhopadhyay A , Smeltzer MP , Hulihan M . MMWR Morb Mortal Wkly Rep 2024 73 (12) 248-254 Sickle cell disease (SCD) remains a public health priority in the United States because of its association with complex health needs, reduced life expectancy, lifelong disabilities, and high cost of care. A cross-sectional analysis was conducted to calculate the crude and race-specific birth prevalence for SCD using state newborn screening program records during 2016-2020 from 11 Sickle Cell Data Collection program states. The percentage distribution of birth mother residence within Social Vulnerability Index quartiles was derived. Among 3,305 newborns with confirmed SCD (including 57% with homozygous hemoglobin S or sickle β-null thalassemia across 11 states, 90% of whom were Black or African American [Black], and 4% of whom were Hispanic or Latino), the crude SCD birth prevalence was 4.83 per 10,000 (one in every 2,070) live births and 28.54 per 10,000 (one in every 350) non-Hispanic Black newborns. Approximately two thirds (67%) of mothers of newborns with SCD lived in counties with high or very high levels of social vulnerability; most mothers lived in counties with high or very high levels of vulnerability for racial and ethnic minority status (89%) and housing type and transportation (64%) themes. These findings can guide public health, health care systems, and community program planning and implementation that address social determinants of health for infants with SCD. Implementation of tailored interventions, including increasing access to transportation, improving housing, and advancing equity in high vulnerability areas, could facilitate care and improve health outcomes for children with SCD. |
Tubal sterilization and cervical cancer underscreening in the United States
Holt HK , Martinez G , Reyes MF , Saraiya M , Qin J , Sawaya GF . J Womens Health (Larchmt) 2024 Background: Tubal sterilization is more commonly utilized by racial/ethnic minority groups and has been implicated in underscreening for cervical cancer. The objective is to determine if prior tubal sterilization is a risk factor for cervical cancer underscreening. Methods: National Survey of Family Growth dataset from 2015 to 2019 used for analysis; data were weighted to represent the 72 million women in the U.S. population aged 22-49. Chi-square tests, Fisher exact tests, and logistic regression were used for analysis. The primary predictor variable was tubal sterilization which was categorized into no previous sterilization, sterilization completed <5 years ago, and sterilization completed ≥5 years ago. The outcome variable was underscreened versus not underscreened. Other predictor variables included age, household income as a percent of federal poverty level, previous live birth, primary care provider, and insurance status. Results: Prevalence of tubal sterilization completed 5 or more years ago was 12.5% and varied by most measured characteristics in univariate analyses. Approximately 8% of women were underscreened for cervical cancer. In multivariable analyses, women with a tubal sterilization 5 or more years ago had 2.64 times the odds (95% confidence interval = 1.75-4.00) of being underscreened for cervical cancer compared with women who did not have a tubal sterilization. Conclusions: Approximately 4.3 million women ages 22-49 in the United States are potentially underscreened for cervical cancer and women with previous tubal ligation ≥5 years ago are more likely to be underscreened. These results may inform the need for culturally sensitive public health messages informing people who have had these procedures about the need for continued screening. |
Equivalency of PDM3700 and PDM3600 dust monitors
Tuchman DP , Mischler SE , Cauda EG , Colinet JF , Rubinstein EN . Min Metall Explor 2024 The PDM3600 and PDM3700 are two closely related person-wearable dust monitors manufactured by Thermo Fisher Scientific. Both are based on tapered element oscillating microbalance technology and provide nearly real-time, mass-based readings of respirable dust concentrations. From a monitoring perspective, the primary difference between the models is the PDM3600 has an integrated cap lamp with attached inlet, while the PDM3700 has no cap lamp and a revised inlet attaches to the worker’s lapel. Using coals of varied origin and employing a wide range of concentrations, side-by-side measurements from these instruments were collected under controlled laboratory conditions and then compared. By use of ordinary least squares and weighted least squares regression methods, followed by mixed model analysis, results suggest there is no statistically significant or practical difference in instrument performance. The two monitors are equivalent for the field dust concentration measurements for which they were designed. © This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply 2024. |
Cost-effectiveness of expanded latent TB infection testing and treatment: Lynn City, Massachusetts, USA
Beeler Asay GR , Woodruff R , Sanderson DM , Fisher CF , Marks SM , Green VD , Tibbs AM , Hill AN , Haptu HH , McManus D , Paradise RK , Auguste-Nelson C , Cochran JJ . Int J Tuberc Lung Dis 2024 28 (1) 21-28 BACKGROUND: Between October 2016 and March 2019, Lynn Community Health Center in Massachusetts implemented a targeted latent TB infection testing and treatment (TTT) program, increasing testing from a baseline of 1,200 patients tested to an average of 3,531 patients tested, or 9% of the population per year.METHODS: We compared pre-implementation TTT, represented by the first two quarters of implementation data, to TTT, represented by 12 quarters of data. Time, diagnostic, and laboratory resources were estimated using micro-costing. Other cost and testing data were obtained from the electronic health record, pharmaceutical claims, and published reimbursement rates. A Markov cohort model estimated future health outcomes and cost-effectiveness from a societal perspective in 2020 US dollars. Monte Carlo simulation generated 95% uncertainty intervals.RESULTS: The TTT program exhibited extended dominance over baseline pre-intervention testing and had an incremental cost-effectiveness ratio (ICER) of US$52,603 (US$22,008â-"US$95,360). When compared to baseline pre-TTT testing, the TTT program averted an estimated additional 7.12 TB cases, 3.49 hospitalizations, and 0.16 deaths per lifetime cohort each year.CONCLUSIONS: TTT was more cost-effective than baseline pre-implementation testing. Lynn Community Health Centerâ-™s experience can help inform other clinics considering expanding latent TB infection testing. |
2022 American College of Rheumatology Guideline for Exercise, Rehabilitation, Diet, and Additional Integrative Interventions for Rheumatoid Arthritis
England BR , Smith BJ , Baker NA , Barton JL , Oatis CA , Guyatt G , Anandarajah A , Carandang K , Chan KK , Constien D , Davidson E , Dodge CV , Bemis-Dougherty A , Everett S , Fisher N , Fraenkel L , Goodman SM , Lewis J , Menzies V , Moreland LW , Navarro-Millan I , Patterson S , Phillips LR , Shah N , Singh N , White D , AlHeresh R , Barbour KE , Bye T , Guglielmo D , Haberman R , Johnson T , Kleiner A , Lane CY , Li LC , Master H , Pinto D , Poole JL , Steinbarger K , Sztubinski D , Thoma L , Tsaltskan V , Turgunbaev M , Wells C , Turner AS , Treadwell JR . Arthritis Rheumatol 2023 75 (8) 1299-1311 OBJECTIVE: To develop initial American College of Rheumatology (ACR) guidelines on the use of exercise, rehabilitation, diet, and additional interventions in conjunction with disease-modifying antirheumatic drugs (DMARDs) as part of an integrative management approach for people with rheumatoid arthritis (RA). METHODS: An interprofessional guideline development group constructed clinically relevant Population, Intervention, Comparator, and Outcome (PICO) questions. A literature review team then completed a systematic literature review and applied the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to rate the certainty of evidence. An interprofessional Voting Panel (n = 20 participants) that included 3 individuals with RA achieved consensus on the direction (for or against) and strength (strong or conditional) of recommendations. RESULTS: The Voting Panel achieved consensus on 28 recommendations for the use of integrative interventions in conjunction with DMARDs for the management of RA. Consistent engagement in exercise received a strong recommendation. Of 27 conditional recommendations, 4 pertained to exercise, 13 to rehabilitation, 3 to diet, and 7 to additional integrative interventions. These recommendations are specific to RA management, recognizing that other medical indications and general health benefits may exist for many of these interventions. CONCLUSION: This guideline provides initial ACR recommendations on integrative interventions for the management of RA to accompany DMARD treatments. The broad range of interventions included in these recommendations illustrates the importance of an interprofessional, team-based approach to RA management. The conditional nature of most recommendations requires clinicians to engage persons with RA in shared decision-making when applying these recommendations. |
Mortality among children aged <5 years living with HIV who are receiving antiretroviral treatment - U.S. President's Emergency Plan for AIDS Relief, 28 supported countries and regions, October 2020-September 2022
Agathis NT , Faturiyele I , Agaba P , Fisher KA , Hackett S , Agyemang E , Mehta N , Kindra G , Morof DF , Mutisya I , Nyabiage L , Battey KA , Olotu E , Maphosa T , Motswere-Chirwa C , Ketlogetswe AT , Mafa-Setswalo J , Mazibuko S , de Deus MIT , Nhaguiombe HG , Machage EM , Mugisa B , Ogundehin DT , Mbelwa C , Birabwa E , Etima M , Adamu Y , Lawal I , Maswai J , Njeru D , Mwambona J , Nguhuni B , Mrina R , Hrapcak S , Siberry GK , Godfrey C , Wolf HT . MMWR Morb Mortal Wkly Rep 2023 72 (48) 1293-1299 Globally, children aged <5 years, including those living with HIV who are not receiving antiretroviral treatment (ART), experience disproportionately high mortality. Global mortality among children living with HIV aged <5 years receiving ART is not well described. This report compares mortality and related clinical measures among infants aged <1 year and children aged 1-4 years living with HIV with those among older persons aged 5-14, 15-49, and ≥50 years living with HIV receiving ART services at all clinical sites supported by the U.S. President's Emergency Plan for AIDS Relief. During October 2020-September 2022, an average of 11,980 infants aged <1 year and 105,510 children aged 1-4 years were receiving ART each quarter; among these infants and children receiving ART, 586 (4.9%) and 2,684 (2.5%), respectively, were reported to have died annually. These proportions of infants and children who died ranged from four to nine times higher in infants aged <1 year, and two to five times higher in children aged 1-4 years, than the proportions of older persons aged ≥5 years receiving ART. Compared with persons aged ≥5 years living with HIV, the proportions of children aged <5 years living with HIV who experienced interruptions in treatment were also higher, and the proportions who had a documented HIV viral load result or a suppressed viral load were lower. Prioritizing and optimizing HIV and general health services for children aged <5 years living with HIV receiving ART, including those recommended in the WHO STOP AIDS Package, might help address these disproportionately poorer outcomes. |
Comparison of serum PFAS concentrations in incumbent and recruit firefighters and longitudinal assessment in recruits
Nematollahi AJ , Fisher JM , Furlong MA , Beamer PI , Goodrich JM , Graber JM , Calafat AM , Botelho JC , Beitel SC , Littau SR , Gulotta JJ , Wallentine DD , Burgess JL . J Occup Environ Med 2023 OBJECTIVE: Firefighters are occupationally exposed to per- and polyfluoroalkyl substances (PFAS). This study objective was to compare serum PFAS concentrations in incumbent and recruit firefighters and evaluate temporal trends among recruits. METHODS: Serum PFAS concentrations were measured in 99 incumbent and 55 recruit firefighters at enrollment in 2015-2016, with follow-up 20-37 months later for recruits. Linear and logistic regression and linear mixed-effects models were used for analyses. Fireground exposure impact on PFAS concentrations was investigated using adjusted linear and logistic regression models. RESULTS: Incumbents had lower n-PFOA and PFNA than recruits and most PFAS significantly decreased over time among male recruits. No significant links were found between cumulative fireground exposures and PFAS concentrations. CONCLUSIONS: Serum PFAS concentrations were not increased in incumbent firefighters compared with recruits and were not associated with cumulative fireground exposures. |
Serum per- and polyfluoroalkyl substance concentrations and longitudinal change in post-infection and post-vaccination SARS-CoV-2 antibodies
Hollister J , Caban-Martinez AJ , Ellingson KD , Beitel S , Fowlkes AL , Lutrick K , Tyner H , Naleway AL , Yoon SK , Gaglani M , Hunt D , Meece J , Mayo Lamberte J , Schaefer Solle N , Rose S , Dunnigan K , Khan SM , Kuntz JL , Fisher JM , Coleman A , Britton A , Thiese M , Hegmann K , Pavuk M , Ramadan F , Fuller S , Nematollahi A , Sprissler R , Burgess JL . Environ Res 2023 239 117297 Per- and polyfluoroalkyl substances (PFAS) are ubiquitous throughout the United States. Previous studies have shown PFAS exposure to be associated with a reduced immune response. However, the relationship between serum PFAS and antibody levels following SARS-CoV-2 infection or COVID-19 vaccination has not been examined. We examined differences in peak immune response and the longitudinal decline of antibodies following SARS-CoV-2 infection and COVID-19 vaccination by serum PFAS levels in a cohort of essential workers in the United States. We measured serum antibodies using an in-house semi-quantitative enzyme-linked immunosorbent assay (ELISA). Two cohorts contributed blood samples following SARS-CoV-2 infection or COVID-19 vaccination. We used linear mixed regression models, adjusting for age, race/ethnicity, gender, presence of chronic conditions, location, and occupation, to estimate differences in immune response with respect to serum PFAS levels. Our study populations included 153 unvaccinated participants that contributed 316 blood draws over a 14-month period following infection, and 860 participants and 2451 blood draws over a 12-month period following vaccination. Higher perfluorooctane sulfonic acid (PFOS), perfluorohexane sulfonic acid (PFHxS), and perfluorononanoic acid (PFNA) concentrations were associated with a lower peak antibody response after infection (p = 0.009, 0.031, 0.015). Higher PFOS, perfluorooctanoic acid (PFOA), PFHxS, and PFNA concentrations were associated with slower declines in antibodies over time after infection (p = 0.003, 0.014, 0.026, 0.025). PFOA, PFOS, PFHxS, and PFNA serum concentrations prior to vaccination were not associated with differences in peak antibody response after vaccination or with differences in decline of antibodies over time after vaccination. These results suggest that elevated PFAS may impede potential immune response to SARS-CoV-2 infection by blunting peak antibody levels following infection; the same finding was not observed for immune response to vaccination. |
Total outward leakage of half-mask respirators and surgical masks used for source control
Myers WR , Yang W , Ryan KJ , Bergman M , Fisher E , Soo JC , Zhuang Z . J Occup Environ Hyg 2023 1-15 Both respirators and surgical masks (SM) are used as source control devices. During the COVID-19 pandemic, there was much interest in understanding the extent of particle total outward leakage (TOL) from these devices. The objective of this study was to quantify the TOL for five categories of devices: SMs, National Institute for Occupational Safety and Health (NIOSH®) Approved N95(®) filtering facepiece respirators (FFRs) without exhalation valves, NIOSH Approved N95 FFRs with exhalation valves (N95 FFRV), NIOSH Approved elastomeric half-mask respirators (EHMRs) with exhalation valves, and NIOSH Approved EHMRs with an SM covering the exhalation valve (EHMRSM). A benchtop test system was designed to test two models of each device category. Each device was mounted on a headform at three faceseal levels (0% faceseal, 50% faceseal, and 100% faceseal). At each faceseal level, the TOL was assessed at three flowrates of minute ventilations of 17, 28, and 39 L/min. The experimental design was a split-split-plot configuration. Device type, faceseal level, flowrate, and the interaction of device type and faceseal level were found to have a significant effect ( P - Value <0.05) on the TOL.This study found that the N95 FFRs without exhalation valves had the lowest mean TOL. The SMs had about three times higher TOL than the N95 FFRs without exhalation valves. The TOL of the N95 FFRV was comparable to that of the SM at 0% and 50% faceseal on average over all conditions, but the N95 FFRV had a significantly higher TOL than the SM at a 100% faceseal. The EHMRs had the highest TOL because of the exhalation valve. Using an SM to cover the exhalation valve did not improve the EHMRs' efficiency in mitigating the TOL. Caution should be exercised when using N95 FFRVs as a source control measure against respiratory activities with heavy work rates, such as performing CPR. Results of this study showed that reduced faceseal leakage for N95 FFRs and SMs improves source control. |
- Page last reviewed:Feb 1, 2024
- Page last updated:Dec 02, 2024
- Content source:
- Powered by CDC PHGKB Infrastructure