Modeling the long term dynamics of pre-vaccination pertussis

The dynamics of strongly immunizing childhood infections is still not well understood. Although reports of successful modeling of several incidence data records can be found in the literature, the key determinants of the observed temporal patterns have not been clearly identified. In particular, different models of immunity waning and degree of protection applied to disease and vaccine induced immunity have been debated in the literature on pertussis. Here we study the effect of disease acquired immunity on the long term patterns of pertussis prevalence. We compare five minimal models, all of which are stochastic, seasonally forced, well-mixed models of infection based on susceptible-infective-recovered dynamics in a closed population. These models reflect different assumptions about the immune response of naive hosts, namely total permanent immunity, immunity waning, immunity waning together with immunity boosting, reinfection of recovered, and repeat infection after partial immunity waning. The power spectra of the output prevalence time series characterize the long term dynamics of the models. For epidemiological parameters consistent with published data for pertussis, the power spectra show quantitative and even qualitative differences that can be used to test their assumptions by comparison with ensembles of several decades long pre-vaccination data records. We illustrate this strategy on two publicly available historical data sets.Comment: paper (31 pages, 11 figures, 1 table) and supplementary material (19 pages, 5 figures, 2 tables

Frequency of instrument, environment, and laboratory technologist contamination during routine diagnostic testing of infectious specimens

ABSTRACT Laboratory testing to support the care of patients with highly infectious diseases may pose a risk for laboratory workers. However, data on the risk of virus transmission during routine laboratory testing conducted using standard personal protective equipment (PPE) are sparse. Our objective was to measure laboratory contamination during routine analysis of patient specimens. Remnant specimens were spiked with the nonpathogenic bacteriophage MS2 at 1.0 × 10 7 PFU/ml, and contamination was assessed using reverse transcriptase PCR (RT-PCR) for MS2. Specimen containers were exteriorly coated with a fluorescent powder to enable the visualization of gross contamination using UV light. Testing was performed by two experienced laboratory technologists using standard laboratory PPE and sample-to-answer instrumentation. Fluorescence was noted on the gloves, bare hands, and laboratory coat cuffs of the laboratory technologist in 36/36 (100%), 13/36 (36%), and 4/36 (11%) tests performed, respectively. Fluorescence was observed in the biosafety cabinet (BSC) in 8/36 (22%) tests, on test cartridges/devices in 14/32 (44%) tests, and on testing accessory items in 29/32 (91%) tests. Fluorescence was not observed on or in laboratory instrumentation or adjacent surfaces. In contrast to fluorescence detection, MS2 detection was infrequent (3/286 instances [1%]) and occurred during test setup for the FilmArray instrument and on FilmArray accessory equipment. The information from this study may provide opportunities for the improvement of clinical laboratory safety practices so as to reduce the risk of pathogen transmission to laboratory workers. </jats:p

Does Gender Discrimination Impact Regular Mammography Screening? Findings from the Race Differences in Screening Mammography Study

Objective: To determine if gender discrimination, conceptualized as a negative life stressor, is a deterrent to adherence to mammography screening guidelines. Methods: African American and white women (1451) aged 40–79 years who obtained an index screening mammogram at one of five urban hospitals in Connecticut between October 1996 and January 1998 were enrolled in this study. This logistic regression analysis includes the 1229 women who completed telephone interviews at baseline and follow-up (average 29.4 months later) and for whom the study outcome, nonadherence to age-specific mammography screening guidelines, was determined. Gender discrimination was measured as lifetime experience in seven possible situations. Results: Gender discrimination, reported by nearly 38% of the study population, was significantly associated with non-adherence to mammography guidelines in women with annual family incomes of $50,000 or greater (or 1.99, 95% CI 1.33, 2.98) and did not differ across racial/ethnic groups. Conclusions: Our findings suggest that gender discrimination can adversely influence regular mammography screening in some women. With nearly half of women nonadherent to screening mammography guidelines in this study and with decreasing mammography rates nationwide, it is important to address the complexity of nonadherence across subgroups of women. Life stressors, such as experiences of gender discrimination, may have considerable consequences, potentially influencing health prevention prioritization in women

A theory-based approach to understanding condom errors and problems reported by men attending an STI clinic

The official published version can be accessed from the link below - Copyright @ 2008 Springer VerlagWe employed the information–motivation–behavioral skills (IMB) model to guide an investigation of correlates for correct condom use among 278 adult (18–35 years old) male clients attending a sexually transmitted infection (STI) clinic. An anonymous questionnaire aided by a CD-recording of the questions was administered. Linear Structural Relations Program was used to conduct path analyses of the hypothesized IMB model. Parameter estimates showed that while information did not directly affect behavioral skills, it did have a direct (negative) effect on condom use errors. Motivation had a significant direct (positive) effect on behavioral skills and a significant indirect (positive) effect on condom use errors through behavioral skills. Behavioral skills had a direct (negative) effect on condom use errors. Among men attending a public STI clinic, these findings suggest brief, clinic-based, safer sex programs for men who have sex with women should incorporate activities to convey correct condom use information, instill motivation to use condoms correctly, and directly enhance men’s behavioral skills for correct use of condoms

Drug-resistant Neisseria gonorrhoeae in Michigan

The increasing prevalence of quinolone-resistant Neisseria gonorrhoeae (QRNG) in the United States is a cause for concern. Detecting resistance is complicated by the widespread use of molecular tests that do not provide isolates for susceptibility testing. The Michigan Department of Community Health developed a sentinel surveillance program to detect antimicrobial drug resistance in N. gonorrhoeae. Sentinel surveillance from 11 laboratories submitted 1,122 isolates for antimicrobial drug susceptibility testing and detected 2 clusters of QRNG from January 2003 to September 2004. These clusters were epidemiologically distinct: one involved young, heterosexual youth, and the other involved older men who have sex with men. This finding led to changes in local treatment recommendations that limited spread of resistant strains. Development of the sentinel program, collection of data, and epidemiologic analysis of the clusters are discussed

Optimizing Treatment of Antimicrobial-resistant Neisseria gonorrhoeae

Optimal point to switch to more expensive drug depends on prevalence of drug resistance an

Environmental Sampling for Spores of Bacillus anthracis

On November 11, 2001, following the bioterrorism-related anthrax attacks, the U.S. Postal Service collected samples at the Southern Connecticut Processing and Distribution Center; all samples were negative for Bacillus anthracis. After a patient in Connecticut died from inhalational anthrax on November 19, the center was sampled again on November 21 and 25 by using dry and wet swabs. All samples were again negative for B. anthracis. On November 28, guided by information from epidemiologic investigation, we sampled the site extensively with wet wipes and surface vacuum sock samples (using HEPA vacuum). Of 212 samples, 6 (3%) were positive, including one from a highly contaminated sorter. Subsequently B. anthracis was also detected in mail-sorting bins used for the patient’s carrier route. These results suggest cross-contaminated mail as a possible source of anthrax for the inhalational anthrax patient in Connecticut. In future such investigations, extensive sampling guided by epidemiologic data is imperative

Disease Surveillance and the Academic, Clinical, and Public Health Communities

The Emerging Infections Programs (EIPs), a population-based network involving 10 state health departments and the Centers for Disease Control and Prevention, complement and support local, regional, and national surveillance and research efforts. EIPs depend on collaboration between public health agencies and clinical and academic institutions to perform active, population-based surveillance for infectious diseases; conduct applied epidemiologic and laboratory research; implement and evaluate pilot prevention and intervention projects; and provide capacity for flexible public health response. Recent EIP work has included monitoring the impact of a new conjugate vaccine on the epidemiology of invasive pneumococcal disease, providing the evidence base used to derive new recommendations to prevent neonatal group B streptococcal disease, measuring the impact of foodborne diseases in the United States, and developing a systematic, integrated laboratory and epidemiologic method for syndrome-based surveillance

Toxic shock syndrome in the United States: surveillance update, 1979 1996.

Menstrual toxic shock syndrome (TSS) emerged as a public health threat to women of reproductive age in 1979 80. We reviewed surveillance data for the period 1979 to 1996, when 5,296 cases were reported, and discuss changes in the epidemiologic features of TSS