A framework for the design, implementation, and evaluation of output-based surveillance systems against zoonotic threats.

Output-based standards set a prescribed target to be achieved by a surveillance system, but they leave the selection of surveillance parameters, such as test type and population to be sampled, to the responsible party in the surveillance area. This allows proportionate legislative surveillance specifications to be imposed over a range of unique geographies. This flexibility makes output-based standards useful in the context of zoonotic threat surveillance, particularly where animal pathogens act as risk indicators for human health or where multiple surveillance streams cover human, animal, and food safety sectors. Yet, these systems are also heavily reliant on the appropriate choice of surveillance options to fit the disease context and the constraints of the organization implementing the surveillance system. Here we describe a framework to assist with designing, implementing, and evaluating output-based surveillance systems showing the effectiveness of a diverse range of activities through a case study example. Despite not all activities being relevant to practitioners in every context, this framework aims to provide a useful toolbox to encourage holistic and stakeholder-focused approaches to the establishment and maintenance of productive output-based surveillance systems.

Reverse-Transcription Loop-Mediated Isothermal Amplification Has High Accuracy for Detecting Severe Acute Respiratory Syndrome Coronavirus 2 in Saliva and Nasopharyngeal/Oropharyngeal Swabs from Asymptomatic and Symptomatic Individuals.

Previous studies have described reverse-transcription loop-mediated isothermal amplification (RT-LAMP) for the rapid detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in nasopharyngeal/oropharyngeal swab and saliva samples. This multisite clinical evaluation describes the validation of an improved sample preparation method for extraction-free RT-LAMP and reports clinical performance of four RT-LAMP assay formats for SARS-CoV-2 detection. Direct RT-LAMP was performed on 559 swabs and 86,760 saliva samples and RNA RT-LAMP on extracted RNA from 12,619 swabs and 12,521 saliva samples from asymptomatic and symptomatic individuals across health care and community settings. For direct RT-LAMP, overall diagnostic sensitivity (DSe) was 70.35% (95% CI, 63.48%-76.60%) on swabs and 84.62% (95% CI, 79.50%-88.88%) on saliva, with diagnostic specificity of 100% (95% CI, 98.98%-100.00%) on swabs and 100% (95% CI, 99.72%-100.00%) on saliva, compared with quantitative RT-PCR (RT-qPCR); analyzing samples with RT-qPCR ORF1ab CT values of ≤25 and ≤33, DSe values were 100% (95% CI, 96.34%-100%) and 77.78% (95% CI, 70.99%-83.62%) for swabs, and 99.01% (95% CI, 94.61%-99.97%) and 87.61% (95% CI, 82.69%-91.54%) for saliva, respectively. For RNA RT-LAMP, overall DSe and diagnostic specificity were 96.06% (95% CI, 92.88%-98.12%) and 99.99% (95% CI, 99.95%-100%) for swabs, and 80.65% (95% CI, 73.54%-86.54%) and 99.99% (95% CI, 99.95%-100%) for saliva, respectively. These findings demonstrate that RT-LAMP is applicable to a variety of use cases, including frequent, interval-based direct RT-LAMP of saliva from asymptomatic individuals who may otherwise be missed using symptomatic testing alone.

Preliminary optimisation of a simplified sample preparation method to permit direct detection of SARS-CoV-2 within saliva samples using reverse-transcription loop-mediated isothermal amplification (RT-LAMP).

We describe the optimisation of a simplified sample preparation method which permits rapid and direct detection of SARS-CoV-2 RNA within saliva, using reverse-transcription loop-mediated isothermal amplification (RT-LAMP). Treatment of saliva samples prior to RT-LAMP by dilution 1:1 in Mucolyse™, followed by dilution in 10 % (w/v) Chelex© 100 Resin and a 98 °C heat step for 2 min enabled detection of SARS-CoV-2 RNA in positive saliva samples. Using RT-LAMP, SARS-CoV-2 RNA was detected in as little as 05:43 min, with no amplification detected in 3097 real-time reverse transcription PCR (rRT-PCR) negative saliva samples from staff tested within a service evaluation study, or for other respiratory pathogens tested (n = 22). Saliva samples can be collected non-invasively, without the need for skilled staff and can be obtained from both healthcare and home settings. Critically, this approach overcomes the requirement for, and validation of, different swabs and the global bottleneck in obtaining access to extraction robots and reagents to enable molecular testing by rRT-PCR. Such testing opens the possibility of public health approaches for effective intervention during the COVID-19 pandemic through regular SARS-CoV-2 testing at a population scale, combined with isolation and contact tracing.

Efficacy of Different Hair and Skin Decontamination Strategies with Identification of Associated Hazards to First Responders.

Background: Established procedures for mass casualty decontamination involve the deployment of equipment for showering with water (such as the ladder pipe system [LPS] and technical decontamination [TD]). This necessarily introduces a short, but critical delay. The incorporation of dry decontamination to the incident response process offers the potential to establish a more rapid and timely intervention. Objectives: To investigate the effectiveness of various dry (DD) and wet decontamination strategies for removing a chemical warfare simulant (methyl salicylate; MS) from the hair and skin of human volunteers. Methods: The simulant was applied to volunteers via whole body exposure to an aerosol. Three decontamination protocols (dry, LPS and technical decontamination) were applied, singly and in various combinations. The efficacy of the protocols was evaluated by fluorescent photography and analysis of residual MS from skin/hair swabs, decontamination materials and air samples. Results: Dry decontamination was effective, with the greatest reduction in skin and hair contamination arising from the "Triple Protocol" (DD+LPS+TD). Secondary hazards associated with contaminated individuals and equipment decreased as the number of decontamination procedures increased. In particular, dry decontamination reduced the potential contact and inhalation hazard arising from used washcloths, towels and vapor within the TD units. Discussion: The introduction of dry decontamination prior to wet forms of decontamination offers a simple strategy to initiate treatment at a much earlier opportunity, with a corresponding improvement in clinical outcomes and substantial reduction of secondary hazards associated with operational processes.

Evaluation of US Federal Guidelines (Primary Response Incident Scene Management [PRISM]) for Mass Decontamination of Casualties During the Initial Operational Response to a Chemical Incident.

STUDY OBJECTIVE: The aim of this study was to evaluate the clinical and operational effectiveness of US federal government guidance (Primary Response Incident Scene Management [PRISM]) for the initial response phase to chemical incidents. METHODS: The study was performed as a large-scale exercise (Operation DOWNPOUR). Volunteers were dosed with a chemical warfare agent simulant to quantify the efficacy of different iterations of dry, ladder pipe system, or technical decontamination. RESULTS: The most effective process was a triple combination of dry, ladder pipe system, and technical decontamination, which attained an average decontamination efficiency of approximately 100% on exposed hair and skin sites. Both wet decontamination processes (ladder pipe system and technical decontamination, alone or in combination with dry decontamination) were also effective (decontamination efficiency >96%). In compliant individuals, dry decontamination was effective (decontamination efficiency approximately 99%), but noncompliance (tentatively attributed to suboptimal communication) resulted in significantly reduced efficacy (decontamination efficiency approximately 70%). At-risk volunteers (because of chronic illness, disability, or language barrier) were 3 to 8 times slower than ambulatory casualties in undergoing dry and ladder pipe system decontamination, a consequence of which may be a reduction in the overall rate at which casualties can be processed. CONCLUSION: The PRISM incident response protocols are fit for purpose for ambulatory casualties. However, a more effective communication strategy is required for first responders (particularly when guiding dry decontamination). There is a clear need to develop more appropriate decontamination procedures for at-risk casualties.

Efficient linking of birth certificate and newborn screening databases for laboratory investigation of congenital cytomegalovirus infection and preterm birth: Florida, 2008.

The objectives of this study are (1) to design an accurate method for linking newborn screening (NBS) and state birth certificate databases to create a de-identified study database; (2) To assess maternal cytomegalovirus (CMV) seroprevalence by measuring CMV IgG in newborn dried blood spots; (3) To assess congenital CMV infection among newborns and possible association with preterm birth. NBS and birth databases were linked and patient records were de-identified. A stratified random sample of records based on gestational age was selected and used to retrieve blood spots from the state NBS laboratory. Serum containing maternal antibodies was eluted from blood spots and tested for the presence of CMV IgG. DNA was extracted from blood spots and tested for the presence of CMV DNA. Analyses were performed with bivariable and multivariable logistic regression models. Linkage rates and specimen collection exceeded 98% of the total possible yielding a final database with 3,101 newborn blood spots. CMV seroprevalence was 91% among Black mothers, 83% among Hispanic mothers, 59% among White mothers, and decreased with increasing amounts of education. The prevalence of CMV infection in newborns was 0.45% and did not vary significantly by gestational age. Successful methods for database linkage, newborn blood spots collection, and de-identification of records can serve as a model for future congenital exposure surveillance projects. Maternal CMV seroprevalence was strongly associated with race/ethnicity and educational level. Congenital CMV infection rates were lower than those reported by other studies and lacked statistical power to examine associations with preterm birth.

Mercury levels and fish consumption practices in women of child-bearing age in the Florida Panhandle.

The southeastern United States, and in particular the coastal areas along the Gulf of Mexico (Gulf Coast) in Florida, experience some of the highest levels of mercury deposition in the country. Although the State of Florida's coastal border is among the longest in the United States, and the State has issued fish consumption advisories due to mercury on multiple fish species, few data have been systematically collected to assess mercury levels in the human population of the state or to assess the efficacy of the consumption advisories. Because of the generally high rate of seafood consumption among coastal populations, the human population in the Florida Panhandle, near Pensacola, FL is potentially exposed to elevated levels of mercury. In the present study, we analyzed hair mercury levels in women of child-bearing age (16-49 years) who had resided near Pensacola, FL for at least 1 year. We also surveyed the fish consumption practices of the cohort and evaluated awareness of the Florida Fish Consumption Advisory. Hair mercury levels were significantly higher in women who consumed fish within the 30 days prior to sampling (p<0.05) and in those women who were unaware of the consumption advisory (p<0.05). Only 31% of the women reported knowledge of the consumption advisory and pregnant women exhibited lower awareness of the advisory than non-pregnant women. The data suggest that public health interventions such as education and fish advisories have not reached the majority of women in the counties surrounding Pensacola who are most at risk from consumption of fish with high levels of mercury.

Community aerial mosquito control and naled exposure.

In October 2004, the Florida Department of Health (FLDOH) and the Centers for Disease Control and Prevention (CDC) assessed human exposure to ultra-low volume (ULV) aerial application of naled. Teams administered activity questionnaires regarding pesticide exposure and obtained baseline urine samples to quantify prespray naled metabolite levels. Following the spray event, participants were asked to collect postspray urine specimens within 12 h of the spray event and at 8-h intervals for up to 40 h. Upon completion, a postspray activity questionnaire was administered to study participants. Two hundred five (87%) participants completed the study. The urine analysis showed that although 67% of prespray urine samples had detectable levels of a naled metabolite, the majority of postspray samples were below the limit of detection (< LOD). Only at the "postspray 6" time period, which corresponds to a time greater than 5 half-lives (> 40 h) following exposure, the number of samples with detectable levels exceeded 50%. There was a significant decrease in naled metabolites from prespray to postspray (= .02), perhaps associated with a significant reduction (< or = 0.05) in some participants that may have resulted in pesticide exposure by means other than the mosquito control operations. These data suggest that aerial spraying of naled does not result in increased levels of naled in humans, provided the naled is used according to label instructions.