Tri-County Health Department

IntroductionDifferences exist in the morphological features of asbestos and the abilities of measuring tools over the spectrum of the particle size distribution in ground bulk mineral powders. Amphiboles and serpentine most often occur naturally without an asbestos component, although amphiboles typically produce elongate mineral particles when ground. For reasons of defining health risks, attempts to conclusively distinguish between asbestos and non-asbestos occurrences are warranted. Asbestiform morphological characteristics are more readily visible in the coarser size fraction of a ground mineral powder. Therefore, a procedure was developed to isolate and analyze the coarse size fraction of mineral mixtures for asbestos.MethodsThe morphological characteristics of asbestos spiked into ground mineral powders at 100 ppm and 500 ppm concentrations were evaluated. Three types of asbestos, Lone Pine tremolite, Health and Safety Laboratory (HSL) chrysotile, and short-fiber Calidria chrysotile, were spiked into a coarsely crushed talc matrix. Spiked samples were aggressively co-ground to simulate a milled mineral powder final product. The coarsest particles in the mixture were isolated using a wet-sieving technique and evaluated by scanning electron microscopy (SEM) and polarizing light microscopy (PLM). A production-scale ultrafine milled talc sample containing trace amounts of amphibole was also analyzed using the wet-sieve approach.ResultsAsbestos was readily detected by both SEM and PLM in the coarsest size fraction at these low concentrations, despite aggressive grinding. Classic morphological features of asbestos, such as occurrence in bundles and presence of long, thin fibers showing curvature, were observed for all types of asbestos by both SEM and PLM at both concentrations. There were no morphology differences between the 500 ppm and 100 ppm concentrations, although fewer particles were observed in the latter, as expected. Trace amounts of amphibole asbestos were detected in the production-scale ultrafine milled talc sample which showed classic asbestiform morphology even though the sample had been ground to a 1.5 μm median particle size.DiscussionResults show that the presence of asbestos can be confirmed in ground bulk mineral powders using this analysis approach and detection by SEM and/or PLM is limited only by the amount of material analyzed. This approach is opposite to types of asbestos analyses that concentrate on the finest particles (such as those performed by transmission electron microscopy (TEM)), which can sometimes be inconclusive. The production-scale ultrafine milled talc sample provided proof of concept for this approach. The techniques described can be used to accurately determine if a mineral product contains asbestos or an asbestos component.

Public health nurse home visiting is a promising approach for addressing the complex needs of families at risk of child maltreatment. The Colorado Nurse Support Program advances service provision by using evidence-based practices to provide tailored assessment and intervention to low-income, primiparous, and multiparous families with children under 18 years of age identified as high risk by county human service systems. This study aimed to test the effects of the Nurse Support Program on child protective services case characteristics between Nurse Support Program families and a demographically comparable reference group of families and evaluate changes in parenting outcomes from pre- to postprogram involvement for Nurse Support Program families. We used a matched comparison group quasi-experimental design in which families in the Nurse Support Program ( n = 48) were compared to families ( n = 150) who were identified using administrative data from Colorado's Comprehensive Child Welfare Information System. Outcomes were child protective case characteristics (child protection referrals, open assessments, founded assessments, open cases, and children's placement in out-of-home care) and parenting outcomes. Nurse Support Program families were less likely to have a child protection case opened or have their child placed in out-of-home care. There were no significant between-group differences in child protection referrals, open assessments, or founded assessments. Families in the Nurse Support Program showed improvements in parenting outcomes over time. Findings suggest that the Nurse Support Program is a successful public health nurse home-visiting approach to promote positive parenting and family preservation among families with complex needs. Implementing tailored public health nurse home-visiting programs, such as the Nurse Support Program, should continue to be evaluated and supported to mitigate the public health risk of child maltreatment.

Forensic engineers are called upon by third parties to provide technical evaluations, repair options, and expert opinions on causes of property damage or personal injury after an incident. As an expert, forensic engineers are expected to limit their testimony to their areas of expertise. Increasingly, however, forensic engineers are being asked to testify on whether certain conduct is “willful and wanton.” Is this testimony proper, allowed, and/or ethical? Absent training or expertise in evaluating “willful and wanton” conduct, the opining forensic engineer may violate ASCE ethics rules, licensure rules, and court rules for expert testimony.

Sufficient sleep duration is associated with student health and wellbeing, but early secondary school start times limit students' sleep opportunity. Despite recommendations that all middle and high schools adopt a healthy school start time policy, one barrier to policy implementation is concerns about the impact on student participation in activities and employment. This study examined student extracurricular activity participation and employment before and after the implementation of healthy secondary school start times. Approximately 24,000 students/year (grades 3–11) completed three annual surveys (pre-change, post-change, follow-up) measuring sleep-wake patterns, extracurricular activity participation, and employment. Following the implementation of an earlier school start time, before-school activity participation decreased for elementary school students, but after-school participation was similar across years. Following the implementation of later school start times, there was a small decrease in after-school activity participation for middle and high school students (~3–4%). Equally important, middle and high school students reported significantly increased sleep duration with later start times, regardless of participation in before- or after-school activities and employment. Study findings support the recommendation for healthy school start time policies.

The operation of a large industrial or other complex mechanical system incorporates a variety of mechanical and electrical subsystems to perform a given task, some of which require interaction by an operator or worker to oversee and control the process. As with anything mechanical, the system also requires periodic maintenance and replacement of worn parts. During the operation of industrial systems, problems can occur and result in catastrophic failures and/or injury. When applying forensic analysis to such failures, a methodical approach is necessary to allow for a deeper understanding of the overall operation of the system. However, once the forensic analysis has been performed, conveying the findings of such a complex system can be challenging. To assist in describing the system and failure, the use of visualization is a powerful tool to clearly convey the findings as well as normal operation. The following paper outlines the process of building a methodology to investigate and lay the proper foundation for visually presenting the findings. To demonstrate the methodology outlined in this paper, a case study involving a boiler system will be used.

Abstract Purpose Monoclonal antibodies target a single epitope or region in an antigen for therapeutic purposes. Given the highly mutant nature of SARS-COV-2 or coronavirus, it is likely that a cocktail of antibodies or a polyclonal antibody targeting multiple regions of the virus might be more beneficial in treating COVID-19. The purpose of this project, based on the reported clinical evaluation of XAV-19 polyclonal antibody in pneumonia patients, is to develop a pharmacokinetic-pharmacodynamic (PK-PD) model to explain the relationship between drug concentrations and reduction in the nasopharyngeal viral load. Methods: The concentration of the drug in a time course was related to the effect at each time point to determine the PK-PD relationship. Using Berkeley-Madonna, a PK-PD mathematical model including a central serum compartment, a peripheral effect compartment, and an Emax model for drug effects was developed to explain the observed drug concentrations and effects. Using published EC50 concentrations for XAV-19 and various variants of SARS-CoV-2, the time course of drug effect was predicted for the virus variants including D614G, alpha, beta, gamma, and delta. Results: The results indicated a counterclockwise hysteresis loop for the PK-PD relationship, suggesting lower effects at the same concentration initially, followed by greater effects at the same concentration later. This is consistent with separation of the effect compartment from the serum compartment, where concentrations are measured. The model explained the observed data well. Conclusion: The PK-PD model is useful in predicting dose-response relationships for the new polyclonal antibody. Further, it can be extended to other emerging variants of the coronavirus.

As self-collected home antigen tests become widely available, a better understanding of their performance during the course of SARS-CoV-2 infection is needed. To evaluate the diagnostic performance of home antigen tests compared with reverse transcription-polymerase chain reaction (RT-PCR) and viral culture by days from illness onset, as well as user acceptability. This prospective cohort study was conducted from January to May 2021 in San Diego County, California, and metropolitan Denver, Colorado. The convenience sample included adults and children with RT-PCR-confirmed infection who used self-collected home antigen tests for 15 days and underwent at least 1 nasopharyngeal swab for RT-PCR, viral culture, and sequencing. SARS-CoV-2 infection. The primary outcome was the daily sensitivity of home antigen tests to detect RT-PCR-confirmed cases. Secondary outcomes included the daily percentage of antigen test, RT-PCR, and viral culture results that were positive, and antigen test sensitivity compared with same-day RT-PCR and cultures. Antigen test use errors and acceptability were assessed for a subset of participants. This study enrolled 225 persons with RT-PCR-confirmed infection (median [range] age, 29 [1-83] years; 117 female participants [52%]; 10 [4%] Asian, 6 [3%] Black or African American, 50 [22%] Hispanic or Latino, 3 [1%] Native Hawaiian or Other Pacific Islander, 145 [64%] White, and 11 [5%] multiracial individuals) who completed 3044 antigen tests and 642 nasopharyngeal swabs. Antigen test sensitivity was 50% (95% CI, 45%-55%) during the infectious period, 64% (95% CI, 56%-70%) compared with same-day RT-PCR, and 84% (95% CI, 75%-90%) compared with same-day cultures. Antigen test sensitivity peaked 4 days after illness onset at 77% (95% CI, 69%-83%). Antigen test sensitivity improved with a second antigen test 1 to 2 days later, particularly early in the infection. Six days after illness onset, antigen test result positivity was 61% (95% CI, 53%-68%). Almost all (216 [96%]) surveyed individuals reported that they would be more likely to get tested for SARS-CoV-2 infection if home antigen tests were available over the counter. The results of this cohort study of home antigen tests suggest that sensitivity for SARS-CoV-2 was moderate compared with RT-PCR and high compared with viral culture. The results also suggest that symptomatic individuals with an initial negative home antigen test result for SARS-CoV-2 infection should test again 1 to 2 days later because test sensitivity peaked several days after illness onset and improved with repeated testing.

ObjectiveTo assess the household secondary infection risk (SIR) of B.1.1.7 (Alpha) and non-Alpha lineages of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among children.Study designDuring January to April 2021, we prospectively followed households with a SARS-CoV-2 infection. We collected questionnaires, serial nasopharyngeal swabs for reverse transcription polymerase chain reaction testing and whole genome sequencing, and serial blood samples for serology testing. We calculated SIRs by primary case age (pediatric vs adult), household contact age, and viral lineage. We evaluated risk factors associated with transmission and described symptom profiles among children.ResultsAmong 36 households with pediatric primary cases, 21 (58%) had secondary infections. Among 91 households with adult primary cases, 51 (56%) had secondary infections. SIRs among pediatric and adult primary cases were 45% and 54%, respectively (OR, 0.79; 95% CI, 0.41-1.54). SIRs among pediatric primary cases with Alpha and non-Alpha lineage were 55% and 46%, respectively (OR, 1.52; 95% CI, 0.51-4.53). SIRs among pediatric and adult household contacts were 55% and 49%, respectively (OR, 1.01; 95% CI, 0.68-1.50). Among pediatric contacts, no significant differences in the odds of acquiring infection by demographic or household characteristics were observed.ConclusionsHousehold transmission of SARS-CoV-2 from children and adult primary cases to household members was frequent. The risk of secondary infection was similar among child and adult household contacts. Among children, household transmission of SARS-CoV-2 and the risk of secondary infection was not influenced by lineage. Continued mitigation strategies (eg, masking, physical distancing, vaccination) are needed to protect at-risk groups regardless of virus lineage circulating in communities.

Despite increasing standardization of developmental screening and referral processes, significant early intervention service disparities exist. The aims of this article are to: (a) describe methods used to develop a decision support tool for caregivers of children with developmental concerns, (b) summarize key aspects of the tool, and (c) share preliminary results regarding the tool's acceptability and usability among key stakeholders. Content and design of the decision support tool was guided by a systematic process outlined by the International Patient Decision Aid Standards (IPDAS) Collaborative. Three focus group interviews were conducted with caregivers (n = 7), early childhood professionals (n = 28), and a mix of caregivers and professionals (N = 20) to assess caregiver decisional needs. In accordance with the IPDAS, a prototype of the decision support tool was iteratively cocreated by a subset of caregivers (n = 7) and early child health professionals (n = 5). The decision support tool leverages images and plain language text to guide caregivers and professionals along key steps of the early identification to service use pathway. Participants identified four themes central to shared decision making: trust, cultural humility and respect, strength-based conversations, and information-sharing. End-users found the tool to be acceptable and useful. The decision support tool described offers an individualized approach for exploring beliefs about child development and developmental delay, considering service options within the context of the family's values, priorities, and preferences, and outlining next steps. Additional research regarding the tool's effectiveness in optimizing shared decision-making and reducing service use disparities is warranted.