Last data update: Apr 28, 2025. (Total: 49156 publications since 2009)
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Query Trace: Fay K[original query] |
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Zika virus: advancing a priority research agenda for preparedness and response
Lackritz EM , Ng LC , Marques ETA , Rabe IB , Bourne N , Staples JE , Méndez-Rico JA , Harris E , Brault AC , Ko AI , Beasley DWC , Leighton T , Wilder-Smith A , Ostrowsky JT , Mehr AJ , Ulrich AK , Velayudhan R , Golding JP , Fay PC , Cehovin A , Moua NM , Moore KA , Osterholm MT , Barrett ADT . Lancet Infect Dis 2025 ![]() ![]() The 2015-16 Zika virus epidemic emerged in the Americas and rapidly spread throughout the region and beyond, showing the epidemic potential of this mosquito-borne Orthoflavivirus and its capacity to cause severe congenital malformations and neurological sequelae. WHO declared the Zika virus epidemic a public health emergency of international concern in 2016. Despite this declaration, there are no licensed Zika virus vaccines, therapeutics, or diagnostic tests appropriate for routine antenatal screening. To address this absence of essential tools to detect and mitigate the threat of future Zika virus outbreaks, a group of global experts developed a priority agenda for Zika virus research and development. This Series paper summarises crucial challenges and knowledge gaps and outlines a comprehensive strategy to advance research, surveillance, global capacity, policy, and investment for Zika virus preparedness and response. |
Measures to prevent and treat Nipah virus disease: research priorities for 2024-29
Moore KA , Mehr AJ , Ostrowsky JT , Ulrich AK , Moua NM , Fay PC , Hart PJ , Golding JP , Benassi V , Preziosi MP , Broder CC , de Wit E , Formenty PBH , Freiberg AN , Gurley ES , Halpin K , Luby SP , Mazzola LT , Montgomery JM , Spiropoulou CF , Mourya DT , Parveen S , Rahman M , Roth C , Wang LF , Osterholm MT . Lancet Infect Dis 2024 Nipah virus causes highly lethal disease, with case-fatality rates ranging from 40% to 100% in recognised outbreaks. No treatments or licensed vaccines are currently available for the prevention and control of Nipah virus infection. In 2019, WHO published an advanced draft of a research and development roadmap for accelerating development of medical countermeasures, including diagnostics, therapeutics, and vaccines, to enable effective and timely emergency response to Nipah virus outbreaks. This Personal View provides an update to the WHO roadmap by defining current research priorities for development of Nipah virus medical countermeasures, based primarily on literature published in the last 5 years and consensus opinion of 15 subject matter experts with broad experience in development of medical countermeasures for Nipah virus or experience in the epidemiology, ecology, or public health control of outbreaks of Nipah virus. The research priorities are organised into four main sections: cross-cutting issues (for those that apply to more than one category of medical countermeasures), diagnostics, therapeutics, and vaccines. The strategic goals and milestones identified in each section focus on key achievements that are needed over the next 6 years to ensure that the necessary tools are available for rapid response to future outbreaks of Nipah virus or related henipaviruses. |
Streptococcus pneumoniae nasal carriage patterns with and without common respiratory virus detections in households in Seattle, WA, USA before and during the COVID-19 pandemic
Bennett JC , Emanuels A , Heimonen J , O'Hanlon J , Hughes JP , Han PD , Chow EJ , Ogokeh CE , Rolfes MA , Lockwood CM , Pfau B , Uyeki TM , Shendure J , Hoag S , Fay K , Lee J , Sibley TR , Rogers JH , Starita LM , Englund JA , Chu HY . Front Pediatr 2023 11 1198278 ![]() ![]() BACKGROUND: Respiratory viruses might influence Streptococcus pneumoniae nasal carriage and subsequent disease risk. We estimated the association between common respiratory viruses and semiquantitative S. pneumoniae nasal carriage density in a household setting before and during the COVID-19 pandemic. METHODS: From November 2019-June 2021, we enrolled participants in a remote household surveillance study of respiratory pathogens. Participants submitted weekly reports of acute respiratory illness (ARI) symptoms. Mid-turbinate or anterior nasal swabs were self-collected at enrollment, when ARI occurred, and, in the second year of the study only, from household contacts after SARS-CoV-2 was detected in a household member. Specimens were tested using multiplex reverse-transcription PCR for respiratory pathogens, including S. pneumoniae, rhinovirus, adenovirus, common human coronavirus, influenza A/B virus, respiratory syncytial virus (RSV) A/B, human metapneumovirus, enterovirus, and human parainfluenza virus. We estimated differences in semiquantitative S. pneumoniae nasal carriage density, estimated by the inverse of S. pneumoniae relative cycle threshold (Crt) values, with and without viral detection for any virus and for specific respiratory viruses using linear generalized estimating equations of S. pneumoniae Crt values on virus detection adjusted for age and swab type and accounting for clustering of swabs within households. RESULTS: We collected 346 swabs from 239 individuals in 151 households that tested positive for S. pneumoniae (n = 157 with and 189 without ≥1 viruses co-detected). Difficulty breathing, cough, and runny nose were more commonly reported among individuals with specimens with viral co-detection compared to without (15%, 80% and 93% vs. 8%, 57%, and 51%, respectively) and ear pain and headache were less commonly reported (3% and 26% vs. 16% and 41%, respectively). For specific viruses among all ages, semiquantitative S. pneumoniae nasal carriage density was greater with viral co-detection for enterovirus, RSV A/B, adenovirus, rhinovirus, and common human coronavirus (P < 0.01 for each). When stratified by age, semiquantitative S. pneumoniae nasal carriage density was significantly greater with viral co-detection among children aged <5 (P = 0.002) and 5-17 years (P = 0.005), but not among adults aged 18-64 years (P = 0.29). CONCLUSION: Detection of common respiratory viruses was associated with greater concurrent S. pneumoniae semiquantitative nasal carriage density in a household setting among children, but not adults. |
Cryptic transmission of SARS-CoV-2 in Washington State.
Bedford T , Greninger AL , Roychoudhury P , Starita LM , Famulare M , Huang ML , Nalla A , Pepper G , Reinhardt A , Xie H , Shrestha L , Nguyen TN , Adler A , Brandstetter E , Cho S , Giroux D , Han PD , Fay K , Frazar CD , Ilcisin M , Lacombe K , Lee J , Kiavand A , Richardson M , Sibley TR , Truong M , Wolf CR , Nickerson DA , Rieder MJ , Englund JA , Hadfield J , Hodcroft EB , Huddleston J , Moncla LH , Müller NF , Neher RA , Deng X , Gu W , Federman S , Chiu C , Duchin J , Gautom R , Melly G , Hiatt B , Dykema P , Lindquist S , Queen K , Tao Y , Uehara A , Tong S , MacCannell D , Armstrong GL , Baird GS , Chu HY , Shendure J , Jerome KR . medRxiv 2020 ![]() ![]() Following its emergence in Wuhan, China, in late November or early December 2019, the SARS-CoV-2 virus has rapidly spread throughout the world. On March 11, 2020, the World Health Organization declared Coronavirus Disease 2019 (COVID-19) a pandemic. Genome sequencing of SARS-CoV-2 strains allows for the reconstruction of transmission history connecting these infections. Here, we analyze 346 SARS-CoV-2 genomes from samples collected between 20 February and 15 March 2020 from infected patients in Washington State, USA. We found that the large majority of SARS-CoV-2 infections sampled during this time frame appeared to have derived from a single introduction event into the state in late January or early February 2020 and subsequent local spread, strongly suggesting cryptic spread of COVID-19 during the months of January and February 2020, before active community surveillance was implemented. We estimate a common ancestor of this outbreak clade as occurring between 18 January and 9 February 2020. From genomic data, we estimate an exponential doubling between 2.4 and 5.1 days. These results highlight the need for large-scale community surveillance for SARS-CoV-2 introductions and spread and the power of pathogen genomics to inform epidemiological understanding. |
Community outbreak of legionellosis associated with an indoor hot tub, New Hampshire, 2018
Daly ER , Talbot EA , Smith JC , Ritter T , McCormic ZD , Fay K , Raphael BH , Kozak-Muiznieks NA , Levinson KJ , Bean CL , Wilson RT , Morse D , Scacheri A , Linxweiler J , Chan BP . J Environ Health 2022 84 (10) 16-25 Legionellosis is an infection acquired through inhalation of aerosolized water droplets containing Legionella bacteria. In August 2018, public health officials in New Hampshire launched an investigation into a legionellosis outbreak. They identified 49 illnesses likely associated with the outbreak and implicated an improperly maintained hot tub at a hotel. The same strain of Legionella pneumophila serogroup 1 was found in both the hot tub and in samples from two patients with Legionnaires disease. The indoor hot tub vented to the outdoors, which is how some patients with confirmed legionellosis likely acquired the infection despite not entering the hotel during the incubation period. This outbreak is notable for 1) likely illness acquisition through the exterior vent of the hot tub room and 2) use of whole genome sequencing to link environmental and patient specimens. Collaboration among public health and environmental officials, laboratorians, and building managers was essential to determining the source of the outbreak and preventing further illness. 2022, National Environmental Health Association. All rights reserved. |
Evaluation of four gamma-based methods for calculating confidence intervals for age-adjusted mortality rates when data are sparse
Talih M , Anderson RN , Parker JD . Popul Health Metr 2022 20 (1) 13 BACKGROUND: Equal-tailed confidence intervals that maintain nominal coverage (0.95 or greater probability that a 95% confidence interval covers the true value) are useful in interval-based statistical reliability standards, because they remain conservative. For age-adjusted death rates, while the Fay-Feuer gamma method remains the gold standard, modifications have been proposed to streamline implementation and/or obtain more efficient intervals (shorter intervals that retain nominal coverage). METHODS: This paper evaluates three such modifications for use in interval-based statistical reliability standards, the Anderson-Rosenberg, Tiwari, and Fay-Kim intervals, when data are sparse and sample size-based standards alone are overly coarse. Initial simulations were anchored around small populations (P = 2400 or 1200), the median crude all-cause US mortality rate in 2010-2019 (833.8 per 100,000), and the corresponding age-specific probabilities of death. To allow for greater variation in the age-adjustment weights and age-specific probabilities, a second set of simulations draws those at random, while holding the mean number of deaths at 20 or 10. Finally, county-level mortality data by race/ethnicity from four causes are selected to capture even greater variation: all causes, external causes, congenital malformations, and Alzheimer disease. RESULTS: The three modifications had comparable performance when the number of deaths was large relative to the denominator and the age distribution was as in the standard population. However, for sparse county-level data by race/ethnicity for rarer causes of death, and for which the age distribution differed sharply from the standard population, coverage probability in all but the Fay-Feuer method sometimes fell below 0.95. More efficient intervals than the Fay-Feuer interval were identified under specific circumstances. When the coefficient of variation of the age-adjustment weights was below 0.5, the Anderson-Rosenberg and Tiwari intervals appeared to be more efficient, whereas when it was above 0.5, the Fay-Kim interval appeared to be more efficient. CONCLUSIONS: As national and international agencies reassess prevailing data presentation standards to release age-adjusted estimates for smaller areas or population subgroups than previously presented, the Fay-Feuer interval can be used to develop interval-based statistical reliability standards with appropriate thresholds that are generally applicable. For data that meet certain statistical conditions, more efficient intervals could be considered. |
Model-based small area estimation methods and precise district-level HIV prevalence estimates in Uganda
Ouma J , Jeffery C , Awor CA , Muruta A , Musinguzi J , Wanyenze RK , Biraro S , Levin J , Valadez JJ . PLoS One 2021 16 (8) e0253375 BACKGROUND: Model-based small area estimation methods can help generate parameter estimates at the district level, where planned population survey sample sizes are not large enough to support direct estimates of HIV prevalence with adequate precision. We computed district-level HIV prevalence estimates and their 95% confidence intervals for districts in Uganda. METHODS: Our analysis used direct survey and model-based estimation methods, including Fay-Herriot (area-level) and Battese-Harter-Fuller (unit-level) small area models. We used regression analysis to assess for consistency in estimating HIV prevalence. We use a ratio analysis of the mean square error and the coefficient of variation of the estimates to evaluate precision. The models were applied to Uganda Population-Based HIV Impact Assessment 2016/2017 data with auxiliary information from the 2016 Lot Quality Assurance Sampling survey and antenatal care data from district health information system datasets for unit-level and area-level models, respectively. RESULTS: Estimates from the model-based and the direct survey methods were similar. However, direct survey estimates were unstable compared with the model-based estimates. Area-level model estimates were more stable than unit-level model estimates. The correlation between unit-level and direct survey estimates was (β1 = 0.66, r2 = 0.862), and correlation between area-level model and direct survey estimates was (β1 = 0.44, r2 = 0.698). The error associated with the estimates decreased by 37.5% and 33.1% for the unit-level and area-level models, respectively, compared to the direct survey estimates. CONCLUSIONS: Although the unit-level model estimates were less precise than the area-level model estimates, they were highly correlated with the direct survey estimates and had less standard error associated with estimates than the area-level model. Unit-level models provide more accurate and reliable data to support local decision-making when unit-level auxiliary information is available. |
Pneumococcal Disease Outbreak at a State Prison, Alabama, USA, September 1-October 10, 2018(1)
Sanchez GV , Bourne CL , Davidson SL , Ellis M , Feldstein LR , Fay K , Brown NE , Geeter EF , Foster LL , Gilmore C , McIntyre MG , Taylor B , Velusamy S , Chochua S , Matanock AM . Emerg Infect Dis 2021 27 (7) 1949-1952 A pneumococcal disease outbreak caused by Streptococcus pneumoniae serotype 12F occurred in a state prison in Alabama, USA. Among 1,276 inmates, 40 cases were identified (3 confirmed, 2 probable, 35 suspected). Close living quarters, substance use, and underlying conditions likely contributed to disease risk. Prophylaxis for close contacts included azithromycin and 23-valent pneumococcal polysaccharide vaccine. |
Patterns of antibiotic nonsusceptibility among invasive group A Streptococcus infections-United States, 2006-2017.
Fay K , Onukwube J , Chochua S , Schaffner W , Cieslak P , Lynfield R , Muse A , Smelser C , Harrison LH , Farley M , Petit S , Alden N , Apostal M , Vagnone PS , Nanduri S , Beall B , Van Beneden CA . Clin Infect Dis 2021 73 (11) 1957-1964 ![]() ![]() BACKGROUND: Treatment of severe group A streptococcal infections requires timely and appropriate antibiotic therapy. We describe the epidemiology of antimicrobial-resistant invasive group A streptococcal (iGAS) infections in the U.S. METHODS: We analyzed population-based iGAS surveillance data at 10 U.S. sites from 2006-2017. Cases were defined as infection with GAS isolated from normally sterile sites or wounds in patients with necrotizing fasciitis or streptococcal toxic shock syndrome. GAS isolates were emm typed. Antimicrobial susceptibility was determined using broth microdilution or whole genome sequencing. We compared characteristics among patients infected with erythromycin nonsusceptible (EryNS) and clindamycin nonsusceptible (CliNS) strains to those with susceptible infections. We analyzed proportions of EryNS and CliNS among isolates by site, year, risk factors and emm type. RESULTS: Overall, 17,179 iGAS cases were reported; 14.5% were EryNS. Among isolates tested for both inducible and constitutive CliNS (2011-2017), 14.6% were CliNS. Most (99.8%) CliNS isolates were EryNS. Resistance was highest in 2017 (EryNS: 22.8%; CliNS: 22.0%). All isolates were susceptible to beta-lactams. EryNS and CliNS infections were most frequent among persons aged 18-34 years and in persons residing in long-term care facilities, experiencing homelessness, incarcerated, or who injected drugs. Patterns varied by site. Patients with nonsusceptible infections were significantly less likely to die. Emm types with >30% EryNS or CliNS included: 77, 58, 11, 83, 92. CONCLUSION: Increasing prevalence of EryNS and CliNS iGAS infections in the U.S. is predominantly due to expansion of several emm types. Clinicians should consider local resistance patterns when treating iGAS infections. |
Comparison of Symptoms and RNA Levels in Children and Adults With SARS-CoV-2 Infection in the Community Setting.
Chung E , Chow EJ , Wilcox NC , Burstein R , Brandstetter E , Han PD , Fay K , Pfau B , Adler A , Lacombe K , Lockwood CM , Uyeki TM , Shendure J , Duchin JS , Rieder MJ , Nickerson DA , Boeckh M , Famulare M , Hughes JP , Starita LM , Bedford T , Englund JA , Chu HY . JAMA Pediatr 2021 175 (10) e212025 ![]() ![]() IMPORTANCE: The association between COVID-19 symptoms and SARS-CoV-2 viral levels in children living in the community is not well understood. OBJECTIVE: To characterize symptoms of pediatric COVID-19 in the community and analyze the association between symptoms and SARS-CoV-2 RNA levels, as approximated by cycle threshold (Ct) values, in children and adults. DESIGN, SETTING, AND PARTICIPANTS: This cross-sectional study used a respiratory virus surveillance platform in persons of all ages to detect community COVID-19 cases from March 23 to November 9, 2020. A population-based convenience sample of children younger than 18 years and adults in King County, Washington, who enrolled online for home self-collection of upper respiratory samples for SARS-CoV-2 testing were included. EXPOSURES: Detection of SARS-CoV-2 RNA by reverse transcription-polymerase chain reaction (RT-PCR) from participant-collected samples. MAIN OUTCOMES AND MEASURES: RT-PCR-confirmed SARS-CoV-2 infection, with Ct values stratified by age and symptoms. RESULTS: Among 555 SARS-CoV-2-positive participants (mean [SD] age, 33.7 [20.1] years; 320 were female [57.7%]), 47 of 123 children (38.2%) were asymptomatic compared with 31 of 432 adults (7.2%). When symptomatic, fewer symptoms were reported in children compared with adults (mean [SD], 1.6 [2.0] vs 4.5 [3.1]). Symptomatic individuals had lower Ct values (which corresponded to higher viral RNA levels) than asymptomatic individuals (adjusted estimate for children, -3.0; 95% CI, -5.5 to -0.6; P = .02; adjusted estimate for adults, -2.9; 95% CI, -5.2 to -0.6; P = .01). The difference in mean Ct values was neither statistically significant between symptomatic children and symptomatic adults (adjusted estimate, -0.7; 95% CI, -2.2 to 0.9; P = .41) nor between asymptomatic children and asymptomatic adults (adjusted estimate, -0.6; 95% CI, -4.0 to 2.8; P = .74). CONCLUSIONS AND RELEVANCE: In this community-based cross-sectional study, SARS-CoV-2 RNA levels, as determined by Ct values, were significantly higher in symptomatic individuals than in asymptomatic individuals and no significant age-related differences were found. Further research is needed to understand the role of SARS-CoV-2 RNA levels and viral transmission. |
Cryptic transmission of SARS-CoV-2 in Washington state.
Bedford T , Greninger AL , Roychoudhury P , Starita LM , Famulare M , Huang ML , Nalla A , Pepper G , Reinhardt A , Xie H , Shrestha L , Nguyen TN , Adler A , Brandstetter E , Cho S , Giroux D , Han PD , Fay K , Frazar CD , Ilcisin M , Lacombe K , Lee J , Kiavand A , Richardson M , Sibley TR , Truong M , Wolf CR , Nickerson DA , Rieder MJ , Englund JA , Hadfield J , Hodcroft EB , Huddleston J , Moncla LH , Müller NF , Neher RA , Deng X , Gu W , Federman S , Chiu C , Duchin JS , Gautom R , Melly G , Hiatt B , Dykema P , Lindquist S , Queen K , Tao Y , Uehara A , Tong S , MacCannell D , Armstrong GL , Baird GS , Chu HY , Shendure J , Jerome KR . Science 2020 370 (6516) 571-575 ![]() ![]() Following its emergence in Wuhan, China, in late November or early December 2019, the SARS-CoV-2 virus has rapidly spread globally. Genome sequencing of SARS-CoV-2 allows reconstruction of its transmission history, although this is contingent on sampling. We have analyzed 453 SARS-CoV-2 genomes collected between 20 February and 15 March 2020 from infected patients in Washington State, USA. We find that most SARS-CoV-2 infections sampled during this time derive from a single introduction in late January or early February 2020 which subsequently spread locally before active community surveillance was implemented. |
Assessment of health care exposures and outcomes in adult patients with sepsis and septic shock
Fay K , Sapiano MRP , Gokhale R , Dantes R , Thompson N , Katz DE , Ray SM , Wilson LE , Perlmutter R , Nadle J , Godine D , Frank L , Brousseau G , Johnston H , Bamberg W , Dumyati G , Nelson D , Lynfield R , DeSilva M , Kainer M , Zhang A , Ocampo V , Samper M , Pierce R , Irizarry L , Sievers M , Maloney M , Fiore A , Magill SS , Epstein L . JAMA Netw Open 2020 3 (7) e206004 Importance: Current information on the characteristics of patients who develop sepsis may help in identifying opportunities to improve outcomes. Most recent studies of sepsis epidemiology have focused on changes in incidence or have used administrative data sets that provided limited patient-level data. Objective: To describe sepsis epidemiology in adults. Design, Setting, and Participants: This retrospective cohort study reviewed the medical records, death certificates, and hospital discharge data of adult patients with sepsis or septic shock who were discharged from the hospital between October 1, 2014, and September 30, 2015. The convenience sample was obtained from hospitals in the Centers for Disease Control and Prevention Emerging Infections Program in 10 states (California, Colorado, Connecticut, Georgia, Maryland, Minnesota, New Mexico, New York, Oregon, and Tennessee). Patients 18 years and older with discharge diagnosis codes for severe sepsis or septic shock were randomly selected. Data were analyzed between May 1, 2018, and January 31, 2019. Main Outcomes and Measures: The population's demographic characteristics, health care exposures, and sepsis-associated infections and pathogens were described, and risk factors for death within 30 days after sepsis diagnosis were assessed. Results: Among 1078 adult patients with sepsis (569 men [52.8%]; median age, 64 years [interquartile range, 53-75 years]), 973 patients (90.3%) were classified as having community-onset sepsis (ie, sepsis diagnosed within 3 days of hospital admission). In total, 654 patients (60.7%) had health care exposures before their hospital admission for sepsis; 260 patients (24.1%) had outpatient encounters in the 7 days before admission, and 447 patients (41.5%) received medical treatment, including antimicrobial drugs, chemotherapy, wound care, dialysis, or surgery, in the 30 days before admission. A pathogen associated with sepsis was found in 613 patients (56.9%); the most common pathogens identified were Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, and Clostridioides difficile. After controlling for other factors, an association was found between underlying comorbidities, such as cirrhosis (odds ratio, 3.59; 95% CI, 2.03-6.32), immunosuppression (odds ratio, 2.52; 95% CI, 1.81-3.52), vascular disease (odds ratio, 1.54; 95% CI, 1.10-2.15), and 30-day mortality. Conclusions and Relevance: Most adults experienced sepsis onset outside of the hospital and had recent encounters with the health care system. A sepsis-associated pathogen was identified in more than half of patients. Future efforts to improve sepsis outcomes may benefit from examination of health maintenance practices and recent health care exposures as potential opportunities among high-risk patients. |
Antenatal and intrapartum nucleic acid amplification test use for group B Streptococcus screening - United States, 2016
Fay K , Almendares O , Robinson-Dunn B , Schrag S . Diagn Microbiol Infect Dis 2018 94 (2) 157-159 Perinatal group B Streptococcus (GBS) disease prevention guidelines in 2010 allowed for processing of screening specimens by nucleic acid amplification tests (NAATs); however, the extent of NAAT use is unknown. A 2016 laboratory survey sent to 10 surveillance sites found that 18.7% of responding laboratories offered NAAT for GBS screening (antenatal only: 7.3%; intrapartum only: 4.1%; both: 3.4%). |
Anthrax vaccine-induced antibodies provide cross-species prediction of survival to aerosol challenge
Fay MP , Follmann DA , Lynn F , Schiffer JM , Stark GV , Kohberger R , Quinn CP , Nuzum EO . Sci Transl Med 2012 4 (151) 151ra126 Because clinical trials to assess the efficacy of vaccines against anthrax are not ethical or feasible, licensure for new anthrax vaccines will likely involve the Food and Drug Administration's "Animal Rule," a set of regulations that allow approval of products based on efficacy data only in animals combined with immunogenicity and safety data in animals and humans. U.S. government-sponsored animal studies have shown anthrax vaccine efficacy in a variety of settings. We examined data from 21 of those studies to determine whether an immunological bridge based on lethal toxin neutralization activity assay (TNA) can predict survival against an inhalation anthrax challenge within and across species and genera. The 21 studies were classified into 11 different settings, each of which had the same animal species, vaccine type and formulation, vaccination schedule, time of TNA measurement, and challenge time. Logistic regression models determined the contribution of vaccine dilution dose and TNA on prediction of survival. For most settings, logistic models using only TNA explained more than 75% of the survival effect of the models with dose additionally included. Cross-species survival predictions using TNA were compared to the actual survival and shown to have good agreement (Cohen's kappa ranged from 0.55 to 0.78). In one study design, cynomolgus macaque data predicted 78.6% survival in rhesus macaques (actual survival, 83.0%) and 72.6% in rabbits (actual survival, 64.6%). These data add support for the use of TNA as an immunological bridge between species to extrapolate data in animals to predict anthrax vaccine effectiveness in humans. |
BirthStats: rates of cesarean delivery, and unassisted and assisted vaginal delivery, United States, 1996, 2000, and 2006
Menacker F , Martin JA . Birth 2009 36 (2) 167 The rise in the rate of birhs by cesarean delivery has been accompanied by a decrease in the rate of vaginal delivery and in the use of forceps or vacuum extraction, methods that are used to assist vaginal delivery (i.e., assisted vaginal delivery). Between 1996 and 2006, birhs by cesarean delivery rose by 50 percent, from 20.7 to 31.1 percent. At the same time, the rate of assisted vaginal delivery declined from 11.8 to 6.6 percent and the rate of unassisted vaginal birhs fell from 67.5 to 62.3 percent. The pace of these changes accelerated between 2000 and 2006. | The decline in the rate of vaginal delivery (both assisted and unassisted) may reflect changes in obstetric training and practice patterns, as well as the continuing debate on the immediate and long-term risks and benefits of vaginal versus cesarean birh for both the mother and infant. | This analysis was prepared by Fay Menacker, DrPH, CPNP, and Joyce A. Martin, MPH, of the Division of Vital Statistics, National Center for Health Statistics, Centers for Disease Control and Prevention, Hyattsville, Maryland, USA. |
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