Genomic surveillance reveals dynamic shifts in the connectivity of COVID-19 epidemics.

The maturation of genomic surveillance in the past decade has enabled tracking of the emergence and spread of epidemics at an unprecedented level. During the COVID-19 pandemic, for example, genomic data revealed that local epidemics varied considerably in the frequency of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) lineage importation and persistence, likely due to a combination of COVID-19 restrictions and changing connectivity. Here, we show that local COVID-19 epidemics are driven by regional transmission, including across international boundaries, but can become increasingly connected to distant locations following the relaxation of public health interventions. By integrating genomic, mobility, and epidemiological data, we find abundant transmission occurring between both adjacent and distant locations, supported by dynamic mobility patterns. We find that changing connectivity significantly influences local COVID-19 incidence. Our findings demonstrate a complex meaning of "local" when investigating connected epidemics and emphasize the importance of collaborative interventions for pandemic prevention and mitigation.

Wastewater sequencing reveals early cryptic SARS-CoV-2 variant transmission.

As SARS-CoV-2 continues to spread and evolve, detecting emerging variants early is critical for public health interventions. Inferring lineage prevalence by clinical testing is infeasible at scale, especially in areas with limited resources, participation, or testing and/or sequencing capacity, which can also introduce biases1-3. SARS-CoV-2 RNA concentration in wastewater successfully tracks regional infection dynamics and provides less biased abundance estimates than clinical testing4,5. Tracking virus genomic sequences in wastewater would improve community prevalence estimates and detect emerging variants. However, two factors limit wastewater-based genomic surveillance: low-quality sequence data and inability to estimate relative lineage abundance in mixed samples. Here we resolve these critical issues to perform a high-resolution, 295-day wastewater and clinical sequencing effort, in the controlled environment of a large university campus and the broader context of the surrounding county. We developed and deployed improved virus concentration protocols and deconvolution software that fully resolve multiple virus strains from wastewater. We detected emerging variants of concern up to 14 days earlier in wastewater samples, and identified multiple instances of virus spread not captured by clinical genomic surveillance. Our study provides a scalable solution for wastewater genomic surveillance that allows early detection of SARS-CoV-2 variants and identification of cryptic transmission.

Industry-specific prevalence of elevated blood lead levels among Pennsylvania workers, 2007-2018.

OBJECTIVES: To use industry-specific denominators to more accurately examine trends in prevalence rates for occupational cases of elevated blood lead levels (eBLLs) in Pennsylvania. METHODS: We used adult (aged ≥16 years) blood lead level data from Pennsylvania (2007-2018) and industry-specific denominator data from the US Census Bureau's County Business Patterns to calculate prevalence rates for eBLLs, defined as ≥25 µg/dL. RESULTS: Of the 19 904 cases with eBLLs, 92% were due to occupational lead exposure, with 83% from workers in the battery manufacturing industry. In 2018, the prevalence rate of eBLLs for battery manufacturing (8036.4 cases per 100 000 employed battery manufacturing workers) was 543 times the overall Pennsylvania prevalence rate. The prevalence rate for battery manufacturing steeply declined 71% from 2007 to 2018. CONCLUSIONS: The battery manufacturing industry had the highest burden of occupational lead exposure in Pennsylvania, illustrating the importance of using industry-specific denominators to accurately identify sources of lead exposure. Although the prevalence rate of eBLLs declined over time, lead exposure remains a major concern among battery manufacturing workers.

Integrating Childhood and Adult Blood Lead Surveillance to Improve Identification and Intervention Efforts.

The Centers for Disease Control and Prevention (CDC) collects information on blood lead levels (BLLs) in the United States through the Childhood Blood Lead Surveillance (CBLS) system (<16 years of age) and the Adult Blood Lead Epidemiology and Surveillance (ABLES) program (≥16 years of age). While both of these state-based national programs share the mutual goal of monitoring and reducing lead exposure in the US population, blood lead data for children and adults are maintained in separate data collection systems. This limits the ability to fully describe lead exposure in the US population across these 2 distinct population groups from sources such as take-home and maternal-child lead exposure. In addition, at the state level, having a unified system to collect, maintain, and analyze child and adult blood lead data provides a more efficient use of limited resources. Based on feedback from state partners, CDC is working to integrate CBLS and ABLES data collection systems at the national level. Several states have developed or are developing an integrated child and adult blood lead data collection system. We highlight efforts undertaken in Wisconsin, Minnesota, North Carolina, Iowa, and Oregon to investigate workplace and take-home lead exposure. Integrating blood lead surveillance data at the national level will enhance CDC's ability to monitor sources of lead exposure from both the home and work environments including paint, water, soil, dust, consumer products, and lead-related industries. Together, an integrated child and adult blood lead surveillance system will offer a coordinated, comprehensive, and systematic public health approach to the surveillance and monitoring of reported BLLs across the US population.

Codability of industry and occupation information from cancer registry records: Differences by patient demographics, casefinding source, payor, and cancer type.

INTRODUCTION: Industry and occupation (I&O) information collected by cancer registries is useful for assessing associations among jobs and malignancies. However, systematic differences in I&O availability can bias findings. METHODS: Codability by patient demographics, payor, identifying (casefinding) source, and cancer site was assessed using I&O text from first primaries diagnosed 2011-2012 and reported to California Cancer Registry. I&O were coded to a U.S. Census code or classified as blank/inadequate/unknown, retired, or not working for pay. RESULTS: Industry was codable for 37% of cases; 50% had "unknown" and 9% "retired" instead of usual industry. Cases initially reported by hospitals, covered by preferred providers, or with known occupational etiology had highest codable industry; cases from private pathology laboratories, with Medicaid, or diagnosed in outpatient settings had least. Occupation results were similar. CONCLUSIONS: Recording usual I&O for retirees and improving linkages for reporting entities without patient access would improve I&O codability and research validity.

Cystathionine: A novel oncometabolite in human breast cancer.

In this study, we have identified cystathionine (CTH), a sulfur containing metabolite, to be selectively enriched in human breast cancer (HBC) tissues (∼50-100 pmoles/mg protein) compared with undetectable levels in normal breast tissues. The accumulation of CTH, specifically in HBC, was attributed to the overexpression of cystathionine beta synthase (CBS), its synthesizing enzyme, and the undetectable levels of its downstream metabolizing enzyme, cystathionine gamma lyase (CGL). Interestingly both CBS and CGL could not be detected in normal breast tissues. We further observed that CTH protected HBC cells against excess reactive oxygen species (ROS) and chemotherapeutic drug-induced apoptosis. Moreover, CTH promoted both mitochondrial and endoplasmic reticulum homeostasis in HBC cells. As both the mitochondria and the endoplasmic reticulum are key organelles regulating the onset of apoptosis, we reasoned that endogenous CTH could be contributing towards increasing the apoptotic threshold in HBC cells. An increased apoptotic threshold is a hallmark of all cancer types, including HBC, and is primarily responsible for drug resistance. Hence this study unravels one of the possible pathways that may contribute towards drug resistance in HBC.

Risk of cancer among firefighters in California, 1988-2007.

BACKGROUND: Most studies of firefighter cancer risks were conducted prior to 1990 and do not reflect risk from advances in building materials. METHODS: A case-control study using California Cancer Registry data (1988-2007) was conducted to evaluate the risk of cancer among firefighters, stratified by race. RESULTS: This study identified 3,996 male firefighters with cancer. Firefighters were found to have a significantly elevated risk for melanoma (odds ratio [OR] = 1.8; 95% confidence interval [CI] 1.4-2.1), multiple myeloma (OR 1.4; 95%CI 1.0-1.8), acute myeloid leukemia (OR 1.4; 95%CI 1.0-2.0), and cancers of the esophagus (OR 1.6; 95%CI 1.2-2.1), prostate (OR 1.5; 95%CI 1.3-1.7), brain (OR 1.5; 95%CI 1.2-2.0), and kidney (OR 1.3; 95%CI 1.0-1.6). CONCLUSIONS: In addition to observing cancer findings consistent with previous research, this study generated novel findings for firefighters with race/ethnicity other than white. It provides additional evidence to support the association between firefighting and several specific cancers.

Acute illness associated with use of pest strips - seven U.S. States and Canada, 2000-2013.

Dichlorvos-impregnated resin strips (DDVP pest strips) are among the few organophosphate products still available for indoor residential use. The residential uses for most other organophosphate products, including most DDVP products, were canceled because they posed unreasonable risks to children. DDVP pest strips act by inhibiting acetylcholinesterase activity in the brain and nerves of insect pests and are designed to gradually release DDVP vapor for up to 4 months. Acute illnesses in humans associated with nonlethal acute exposures usually resolve completely, but recovery is not always rapid. To assess the frequency of acute illnesses associated with DDVP pest strips, cases from 2000 through June 2013 were sought from the 12 states that participate in the Sentinel Event Notification System for Occupational Risks (SENSOR)-Pesticides Program, the National Pesticide Information Center (NPIC), and Health Canada.* A total of 31 acute DDVP pest strip-related illness cases were identified in seven U.S. states and Canada. The majority of these illnesses resulted from use of the product in commonly occupied living areas (e.g., kitchens and bedrooms), in violation of label directions. Although 26 of the 31 cases involved mild health effects of short duration, five persons had moderate health effects. Illnesses caused by excess exposure to DDVP pest strips can be reduced by educating the public about the proper usage of DDVP pest strips and with improvements in label directions.

Shift work and cancer screening: do females who work alternative shifts undergo recommended cancer screening?

BACKGROUND: Alternative shift work is classified as a probable human carcinogen. Certain cancer screening tests reduce cancer mortality. METHODS: The 2010 National Health Interview Survey was used to examine associations between adherence to breast, cervical, and colon cancer screening recommendations and alternative shift work among female workers. RESULTS: Workers on alternative shifts, compared to workers on daytime shifts, were more likely to be non-adherent to screening recommendations for breast (34% vs. 23%) and colorectal (55% vs. 48%) cancer (P < 0.05). Workers on alternative shifts in two industries ("Manufacturing" and "Accommodation/Food Services") and three occupations ("Food Preparation/Serving," "Personal Care Services," and "Production") were more likely to be non-adherent to screening recommendations for at least two cancers (P < 0.05). CONCLUSIONS: The Affordable Care Act eliminates out-of-pocket screening expenses for these three cancers. Greater efforts are needed to promote this benefit, particularly among workers with demonstrated non-adherence. Am. J. Ind. Med. 57:265-275, 2014. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

Sentinel Cards Provide Practical SARS-CoV-2 Monitoring in School Settings.

A promising approach to help students safely return to in person learning is through the application of sentinel cards for accurate high resolution environmental monitoring of SARS-CoV-2 traces indoors. Because SARS-CoV-2 RNA can persist for up to a week on several indoor surface materials, there is a need for increased temporal resolution to determine whether consecutive surface positives arise from new infection events or continue to report past events. Cleaning sentinel cards after sampling would provide the needed resolution but might interfere with assay performance. We tested the effect of three cleaning solutions (BZK wipes, Wet Wipes, RNase Away) at three different viral loads: "high" (4 × 104 GE/mL), "medium" (1 × 104 GE/mL), and "low" (2.5 × 103 GE/mL). RNase Away, chosen as a positive control, was the most effective cleaning solution on all three viral loads. Wet Wipes were found to be more effective than BZK wipes in the medium viral load condition. The low viral load condition was easily reset with all three cleaning solutions. These findings will enable temporal SARS-CoV-2 monitoring in indoor environments where transmission risk of the virus is high and the need to avoid individual-level sampling for privacy or compliance reasons exists. IMPORTANCE Because SARS-CoV-2, the virus that causes COVID-19, persists on surfaces, testing swabs taken from surfaces is useful as a monitoring tool. This approach is especially valuable in school settings, where there are cost and privacy concerns that are eliminated by taking a single sample from a classroom. However, the virus persists for days to weeks on surface samples, so it is impossible to tell whether positive detection events on consecutive days are a persistent signal or new infectious cases and therefore whether the positive individuals have been successfully removed from the classroom. We compare several methods for cleaning "sentinel cards" to show that this approach can be used to identify new SARS-CoV-2 signals day to day. The results are important for determining how to monitor classrooms and other indoor environments for SARS-CoV-2 virus.

Implementation of Practical Surface SARS-CoV-2 Surveillance in School Settings.

Surface sampling for SARS-CoV-2 RNA detection has shown considerable promise to detect exposure of built environments to infected individuals shedding virus who would not otherwise be detected. Here, we compare two popular sampling media (VTM and SDS) and two popular workflows (Thermo and PerkinElmer) for implementation of a surface sampling program suitable for environmental monitoring in public schools. We find that the SDS/Thermo pipeline shows superior sensitivity and specificity, but that the VTM/PerkinElmer pipeline is still sufficient to support surface surveillance in any indoor setting with stable cohorts of occupants (e.g., schools, prisons, group homes, etc.) and may be used to leverage existing investments in infrastructure. IMPORTANCE The ongoing COVID-19 pandemic has claimed the lives of over 5 million people worldwide. Due to high density occupancy of indoor spaces for prolonged periods of time, schools are often of concern for transmission, leading to widespread school closings to combat pandemic spread when cases rise. Since pediatric clinical testing is expensive and difficult from a consent perspective, we have deployed surface sampling in SASEA (Safer at School Early Alert), which allows for detection of SARS-CoV-2 from surfaces within a classroom. In this previous work, we developed a high-throughput method which requires robotic automation and specific reagents that are often not available for public health laboratories such as the San Diego County Public Health Laboratory (SDPHL). Therefore, we benchmarked our method (Thermo pipeline) against SDPHL's (PerkinElmer) more widely used method for the detection and prediction of SARS-CoV-2 exposure. While our method shows superior sensitivity (false-negative rate of 9% versus 27% for SDPHL), the SDPHL pipeline is sufficient to support surface surveillance in indoor settings. These findings are important since they show that existing investments in infrastructure can be leveraged to slow the spread of SARS-CoV-2 not in just the classroom but also in prisons, nursing homes, and other high-risk, indoor settings.

SARS-CoV-2 Distribution in Residential Housing Suggests Contact Deposition and Correlates with Rothia sp.

Monitoring severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on surfaces is emerging as an important tool for identifying past exposure to individuals shedding viral RNA. Our past work demonstrated that SARS-CoV-2 reverse transcription-quantitative PCR (RT-qPCR) signals from surfaces can identify when infected individuals have touched surfaces and when they have been present in hospital rooms or schools. However, the sensitivity and specificity of surface sampling as a method for detecting the presence of a SARS-CoV-2 positive individual, as well as guidance about where to sample, has not been established. To address these questions and to test whether our past observations linking SARS-CoV-2 abundance to Rothia sp. in hospitals also hold in a residential setting, we performed a detailed spatial sampling of three isolation housing units, assessing each sample for SARS-CoV-2 abundance by RT-qPCR, linking the results to 16S rRNA gene amplicon sequences (to assess the bacterial community at each location), and to the Cq value of the contemporaneous clinical test. Our results showed that the highest SARS-CoV-2 load in this setting is on touched surfaces, such as light switches and faucets, but a detectable signal was present in many untouched surfaces (e.g., floors) that may be more relevant in settings, such as schools where mask-wearing is enforced. As in past studies, the bacterial community predicts which samples are positive for SARS-CoV-2, with Rothia sp. showing a positive association. IMPORTANCE Surface sampling for detecting SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), is increasingly being used to locate infected individuals. We tested which indoor surfaces had high versus low viral loads by collecting 381 samples from three residential units where infected individuals resided, and interpreted the results in terms of whether SARS-CoV-2 was likely transmitted directly (e.g., touching a light switch) or indirectly (e.g., by droplets or aerosols settling). We found the highest loads where the subject touched the surface directly, although enough virus was detected on indirectly contacted surfaces to make such locations useful for sampling (e.g., in schools, where students did not touch the light switches and also wore masks such that they had no opportunity to touch their face and then the object). We also documented links between the bacteria present in a sample and the SARS-CoV-2 virus, consistent with earlier studies.

Wastewater sequencing uncovers early, cryptic SARS-CoV-2 variant transmission.

As SARS-CoV-2 continues to spread and evolve, detecting emerging variants early is critical for public health interventions. Inferring lineage prevalence by clinical testing is infeasible at scale, especially in areas with limited resources, participation, or testing/sequencing capacity, which can also introduce biases. SARS-CoV-2 RNA concentration in wastewater successfully tracks regional infection dynamics and provides less biased abundance estimates than clinical testing. Tracking virus genomic sequences in wastewater would improve community prevalence estimates and detect emerging variants. However, two factors limit wastewater-based genomic surveillance: low-quality sequence data and inability to estimate relative lineage abundance in mixed samples. Here, we resolve these critical issues to perform a high-resolution, 295-day wastewater and clinical sequencing effort, in the controlled environment of a large university campus and the broader context of the surrounding county. We develop and deploy improved virus concentration protocols and deconvolution software that fully resolve multiple virus strains from wastewater. We detect emerging variants of concern up to 14 days earlier in wastewater samples, and identify multiple instances of virus spread not captured by clinical genomic surveillance. Our study provides a scalable solution for wastewater genomic surveillance that allows early detection of SARS-CoV-2 variants and identification of cryptic transmission.

Prevalence of Diagnosed Diabetes Among Employed US Adults by Demographic Characteristics and Occupation, 36 States, 2014 to 2018.

OBJECTIVE: To assess the prevalence of diagnosed diabetes among employed US adults from 36 states by occupation group using data from 2014 to 2018 Behavioral Risk Factor Surveillance System. METHODS: Prevalence of diabetes was calculated by 22 broad and 93 detailed occupation groups among a sample of 366,633 employed respondents. Wald chi-square values were used to determine the significance of associations between diabetes and occupation groups after adjusting for sex, age, and race/ethnicity. RESULTS: The prevalence of diabetes was 6.4% among employed US adults. The three broad occupation groups with the highest adjusted prevalence of diabetes were protective services (8.9%), farming, fishing, and forestry (8.8%), and community and social services (8.4%). CONCLUSIONS: Prevalence of diabetes differed by occupation. Work-related factors (eg, shift work, job stress) should be further examined in relation to risk of developing diabetes.

Comparison of heat-inactivated and infectious SARS-CoV-2 across indoor surface materials shows comparable RT-qPCR viral signal intensity and persistence.

Environmental monitoring in public spaces can be used to identify surfaces contaminated by persons with COVID-19 and inform appropriate infection mitigation responses. Research groups have reported detection of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) on surfaces days or weeks after the virus has been deposited, making it difficult to estimate when an infected individual may have shed virus onto a SARS-CoV-2 positive surface, which in turn complicates the process of establishing effective quarantine measures. In this study, we determined that reverse transcription-quantitative polymerase chain reaction (RT-qPCR) detection of viral RNA from heat-inactivated particles experiences minimal decay over seven days of monitoring on eight out of nine surfaces tested. The properties of the studied surfaces result in RT-qPCR signatures that can be segregated into two material categories, rough and smooth, where smooth surfaces have a lower limit of detection. RT-qPCR signal intensity (average quantification cycle (Cq)) can be correlated to surface viral load using only one linear regression model per material category. The same experiment was performed with infectious viral particles on one surface from each category, with essentially identical results. The stability of RT-qPCR viral signal demonstrates the need to clean monitored surfaces after sampling to establish temporal resolution. Additionally, these findings can be used to minimize the number of materials and time points tested and allow for the use of heat-inactivated viral particles when optimizing environmental monitoring methods.

SARS-CoV-2 Distribution in Residential Housing Suggests Contact Deposition and Correlates with Rothia sp.

Monitoring severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on surfaces is emerging as an important tool for identifying past exposure to individuals shedding viral RNA. Our past work has demonstrated that SARS-CoV-2 reverse transcription-quantitative PCR (RT-qPCR) signals from surfaces can identify when infected individuals have touched surfaces such as Halloween candy, and when they have been present in hospital rooms or schools. However, the sensitivity and specificity of surface sampling as a method for detecting the presence of a SARS-CoV-2 positive individual, as well as guidance about where to sample, has not been established. To address these questions, and to test whether our past observations linking SARS-CoV-2 abundance to Rothia spp. in hospitals also hold in a residential setting, we performed detailed spatial sampling of three isolation housing units, assessing each sample for SARS-CoV-2 abundance by RT-qPCR, linking the results to 16S rRNA gene amplicon sequences to assess the bacterial community at each location and to the Cq value of the contemporaneous clinical test. Our results show that the highest SARS-CoV-2 load in this setting is on touched surfaces such as light switches and faucets, but detectable signal is present in many non-touched surfaces that may be more relevant in settings such as schools where mask wearing is enforced. As in past studies, the bacterial community predicts which samples are positive for SARS-CoV-2, with Rothia sp. showing a positive association. IMPORTANCE: Surface sampling for detecting SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), is increasingly being used to locate infected individuals. We tested which indoor surfaces had high versus low viral loads by collecting 381 samples from three residential units where infected individuals resided, and interpreted the results in terms of whether SARS-CoV-2 was likely transmitted directly (e.g. touching a light switch) or indirectly (e.g. by droplets or aerosols settling). We found highest loads where the subject touched the surface directly, although enough virus was detected on indirectly contacted surfaces to make such locations useful for sampling (e.g. in schools, where students do not touch the light switches and also wear masks so they have no opportunity to touch their face and then the object). We also documented links between the bacteria present in a sample and the SARS-CoV-2 virus, consistent with earlier studies.

Analysis of SARS-CoV-2 RNA Persistence across Indoor Surface Materials Reveals Best Practices for Environmental Monitoring Programs.

Environmental monitoring in public spaces can be used to identify surfaces contaminated by persons with coronavirus disease 2019 (COVID-19) and inform appropriate infection mitigation responses. Research groups have reported detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on surfaces days or weeks after the virus has been deposited, making it difficult to estimate when an infected individual may have shed virus onto a SARS-CoV-2-positive surface, which in turn complicates the process of establishing effective quarantine measures. In this study, we determined that reverse transcription-quantitative PCR (RT-qPCR) detection of viral RNA from heat-inactivated particles experiences minimal decay over 7 days of monitoring on eight out of nine surfaces tested. The properties of the studied surfaces result in RT-qPCR signatures that can be segregated into two material categories, rough and smooth, where smooth surfaces have a lower limit of detection. RT-qPCR signal intensity (average quantification cycle [Cq]) can be correlated with surface viral load using only one linear regression model per material category. The same experiment was performed with untreated viral particles on one surface from each category, with essentially identical results. The stability of RT-qPCR viral signal demonstrates the need to clean monitored surfaces after sampling to establish temporal resolution. Additionally, these findings can be used to minimize the number of materials and time points tested and allow for the use of heat-inactivated viral particles when optimizing environmental monitoring methods. IMPORTANCE Environmental monitoring is an important tool for public health surveillance, particularly in settings with low rates of diagnostic testing. Time between sampling public environments, such as hospitals or schools, and notifying stakeholders of the results should be minimal, allowing decisions to be made toward containing outbreaks of coronavirus disease 2019 (COVID-19). The Safer At School Early Alert program (SASEA) (https://saseasystem.org/), a large-scale environmental monitoring effort in elementary school and child care settings, has processed >13,000 surface samples for SARS-CoV-2, detecting viral signals from 574 samples. However, consecutive detection events necessitated the present study to establish appropriate response practices around persistent viral signals on classroom surfaces. Other research groups and clinical labs developing environmental monitoring methods may need to establish their own correlation between RT-qPCR results and viral load, but this work provides evidence justifying simplified experimental designs, like reduced testing materials and the use of heat-inactivated viral particles.

Development of Job Exposure Matrices to Estimate Occupational Exposure to Solar and Artificial Ultraviolet Radiation.

OBJECTIVES: Job exposure matrices (JEMs) are important tools for estimating occupational exposures in study populations where only information on industry and occupation (I&O) are available. JEMs The objective of this work was to create JEMs for solar and artificial ultraviolet radiation (UVR) using a US standardized coding scheme. METHODS: Using U.S. Census Bureau industry and occupation codes, separate lists of I&O pairs were developed for solar and artificial UVR by a panel of Certified Industrial Hygienists who assigned exposure ratings to I&O pairs with potential exposure. Parameters for exposure included prevalence (P) and frequency (F) for solar UVR and P, F, and intensity (I) for artificial UVR. Prevalence, or percent of all workers employed in an I&O pair who were exposed, was categorically rated: 0 to <1, 1 to <20; 20 to <80, and ≥80. Frequency of exposure, defined by the number of hours per week workers were exposed, was categorically rated: 0 to <5, 5 to <20, 20 to <35, and ≥35 h per week. For artificial UVR only, intensity of exposure was assigned three ratings: low, low with rare excursions, and >low under normal conditions. Discrepant ratings were resolved via consensus. RESULTS: After excluding I&O pairs assigned P and F ratings of 0 (solar UVR) and P, F, and I ratings of 0 (artificial UVR) from the JEM, 9206 I&O pairs were rated for solar UVR and 2010 I&O pairs for artificial UVR. For solar UVR, 723 (7.9% of all rated pairs) had ratings in the highest category for P and F; this group included 45 occupations in varied industries. Construction and extraction occupations represented most of the occupations (n = 20; 44%), followed by farming, fishing, and forestry occupations (n = 6; 13%). For artificial UVR, 87 I&O pairs (4.3% of all rated pairs) had maximum ratings for P, F, and I; these comprised a single occupation (welding, soldering, and brazing workers) in diverse industries. CONCLUSIONS: JEMs for solar and artificial UVR were developed for a broad range of I&O pairs in the US population and are available for use by researchers conducting occupational epidemiological studies.

Using mobile multimedia platforms in teaching dental diagnosis.

OBJECTIVE: Mobile Multimedia Platforms (MMPs) are prolific tools that can be used by individuals and corporations to share content. However, few studies have shown the effectiveness of MMPs as educational tools. Through this study, we aimed to evaluate the effectiveness of MMPs in improving basic dental diagnostic skills. In addition, we captured student feedback on the use of MMPs in a dental curriculum. METHOD: In this voluntary interventional study on 89 senior dental students, we created pilot learning modules through an MMP called Instagram Stories to teach dental diagnosis. We evaluated the efficacy of the modules through diagnostic tests that were given to dental students who were close to graduating. RESULTS: The students showed a significant increase in diagnostic test scores from 49% to 73% (p < 0.05) after the use of an MMP. Furthermore, the students' feedback on the MMP indicated that most students found it easy and enjoyable to use. CONCLUSION: Our study data show that MMPs may be used to improve training in basic dental diagnostic skills and can serve as an adjunct teaching tool. Moreover, MMP modules can potentially enrich professional education in developing countries where access to educational resources is limited.

The risk of developing arm lymphedema among breast cancer survivors: a meta-analysis of treatment factors.

BACKGROUND: As more women survive breast cancer, long-term complications that affect quality of life, such as lymphedema of the arm, gain greater importance. Numerous studies have attempted to identify treatment and prognostic factors for arm lymphedema, yet the magnitude of these associations remains inconsistent. METHODS: A PubMed search was conducted through January 2008 to locate articles on lymphedema and treatment factors after breast cancer diagnosis. Random-effect models were used to estimate the pooled risk ratio. RESULTS: The authors identified 98 independent studies that reported at least one risk factor of interest. The risk ratio (RR) of arm lymphedema was increased after mastectomy when compared with lumpectomy [RR = 1.42; 95% confidence interval (CI) 1.15-1.76], axillary dissection compared with no axillary dissection (RR = 3.47; 95% CI 2.34-5.15), axillary dissection compared with sentinel node biopsy (RR = 3.07; 95% CI 2.20-4.29), radiation therapy (RR = 1.92; 95% CI 1.61-2.28), and positive axillary nodes (RR = 1.54; 95% CI 1.32-1.80). These associations held when studies using self-reported lymphedema were excluded. CONCLUSIONS: Mastectomy, extent of axillary dissection, radiation therapy, and presence of positive nodes increased risk of developing arm lymphedema after breast cancer. These factors likely reflected lymph node removal, which most surgeons consider to be the largest risk factor for lymphedema. Future studies should consider examining sentinel node biopsy versus no dissection with a long follow-up time post surgery to see if there is a benefit of decreased lymphedema compared with no dissection.