Development and Evaluation of the Ally Sexual and Gender Minority Diversity and Inclusion Training at the Centers for Disease Control and Prevention.

CONTEXT: The Centers for Disease Control and Prevention (CDC) developed a workforce training on sexual and gender minorities (SGMs). OBJECTIVE: This article describes the evaluation of the training. DESIGN: Participants completed pre- and posttest surveys. After the pilot evaluation, some improvements were made to the curriculum and to the pre- and posttest questionnaires. Participants in subsequent (implementation) training were similarly asked to complete pre- and posttest questionnaires. SETTING: CDC. PARTICIPANTS: CDC staff. MAIN OUTCOME MEASURES: Participants' knowledge, ally identity, and perceptions of SGMs. RESULTS: Pilot and implementation training data showed increases in participant knowledge of 44% and 49%, respectively, increases in ally identity of 11% and 14%, respectively, and increases in positive perceptions of SGM of 25% and 31%, respectively. CONCLUSION: These results suggest that the CDC Ally Training may be a useful tool for improving staff knowledge and perceptions of SGM people.

Impact of Epidemic Intelligence Service Training in Occupational Respiratory Epidemiology.

The Centers for Disease Control and Prevention's Epidemic Intelligence Service (EIS) is a fellowship in applied epidemiology for physicians, veterinarians, nurses, scientists, and other health professionals. Each EIS fellow is assigned to a position at a federal, state, or local site for 2 years of on-the-job training in outbreak investigation, epidemiologic research, surveillance system evaluation, and scientific communication. Although the original focus of the program on the control of infectious diseases remains salient, positions are available for training in other areas of public health, including occupational respiratory disease. In this Perspective, we describe the EIS program, highlight three positions (one federal and two state-based) that provide training in occupational respiratory epidemiology, and summarize trainees' experiences in these positions over a 30-year period. For early-career health professionals interested in understanding and preventing occupational respiratory hazards and diseases, EIS offers a unique career development opportunity.

Will clinical standards not be part of the choir? Harmonization between the HL7 gender harmony project model and the NASEM measuring sex, gender identity, and sexual orientation report in the United States.

OBJECTIVES: To propose an approach for semantic and functional data harmonization related to sex and gender constructs in electronic health records (EHRs) and other clinical systems for implementors, as outlined in the National Academies of Sciences, Engineering, and Medicine (NASEM) report Measuring Sex, Gender Identity, and Sexual Orientation and the Health Level 7 (HL7) Gender Harmony Project (GHP) product brief "Gender Harmony-Modeling Sex and Gender Representation, Release 1." MATERIALS AND METHODS: Authors from both publications contributed to a plan for data harmonization based upon fundamental principles in informatics, including privacy, openness, access, legitimate infringement, least intrusive alternatives, and accountability. RESULTS: We propose construct entities and value sets that best align with both publications to allow the implementation of EHR data elements on gender identity, recorded sex or gender, and sex for clinical use in the United States. We include usability- and interoperability-focused reasoning for each of these decisions, as well as suggestions for cross-tabulation for populations. DISCUSSION AND CONCLUSION: Both publications agree on core approaches to conceptualization and measurement of sex- and gender-related constructs. However, some clarifications could improve our ability to assess gender modality, alignment (or lack thereof) between gender identity and assigned gender at birth, and address both individual-level and population-level health inequities. By bridging the GHP and NASEM recommendations, we provide a path forward for implementation of sex- and gender-related EHR elements. Suggestions for implementation of gender identity, recorded sex or gender, and sex for clinical use are provided, along with semantic and functional justifications.

Decrements in lung function and respiratory abnormalities associated with exposure to diacetyl and 2,3-pentanedione in coffee production workers.

Coffee production workers are exposed to complex mixtures of gases, dust, and vapors, including the known respiratory toxins, diacetyl, and 2,3-pentanedione, which occur naturally during coffee roasting and are also present in flavorings used to flavor coffee. This study evaluated the associations of these two α-diketones with lung function measures in coffee production workers. Workers completed questionnaires, and their lung function was assessed by spirometry and impulse oscillometry (IOS). Personal exposures to diacetyl, 2,3-pentanedione, and their sum (SumDA+PD) were assigned to participants, and metrics of the highest 95th percentile (P95), cumulative, and average exposure were calculated. Linear and logistic regression models for continuous and binary/polytomous outcomes, respectively, were used to explore exposure-response relationships adjusting for age, body mass index, tenure, height, sex, smoking status, race, or allergic status. Decrements in percent predicted forced expiratory volume in 1 second (ppFEV1) and forced vital capacity (ppFVC) were associated with the highest-P95 exposures to 2,3-pentanedione and SumDA+PD. Among flavoring workers, larger decrements in ppFEV1 and ppFVC were associated with highest-P95 exposures to diacetyl, 2,3-pentanedione, and SumDA+PD. Abnormal FEV1, FVC, and restrictive spirometric patterns were associated with the highest-P95, cumulative, and average exposures for all α-diketone metrics; some of these associations were also present among flavoring and non-flavoring workers. The combined category of small and peripheral airways plus small and large airways abnormalities on IOS had elevated odds for highest-P95 exposure to α-diketones. These results may be affected by the small sample size, few cases of abnormal spirometry, and the healthy worker effect. Associations between lung function abnormalities and exposure to α-diketones suggest it may be prudent to consider exposure controls in both flavoring and non-flavoring settings.

Associations of Emergency Department Visits for Asthma with Precipitation and Temperature on Thunderstorm Days: A Time-Series Analysis of Data from Louisiana, USA, 2010-2012.

BACKGROUND: Studies of thunderstorm asthma to understand risk factors using high-resolution climate data and asthma outcomes on a large scale are scarce. Moreover, thunderstorm asthma is not well studied in the United States. OBJECTIVES: We examined whether climate parameters involved in thunderstorms are associated with emergency department (ED) visits for acute asthma attacks in the United States. METHODS: We analyzed 63,789 asthma-related, daily ED visits for all age groups, and thunderstorm-associated climate data in Louisiana during 2010 through 2012. We performed time-series analyses using quasi-Poisson regression models with natural cubic splines of date, parish, holiday, day of week, season, daily maximum concentrations of ozone (O3) and fine particulate matter [PM ≤2.5µm in aerodynamic diameter (PM2.5)], and daily mean pressure, precipitation, and temperature. Because of a significant interaction effect between temperature and lightning days on asthma-related visits, we performed stratified analyses by days with/without lightning or thunderstorm (defined by any lightning and precipitation). RESULTS: On thunderstorm days, higher asthma-related ED visits were associated with higher daily mean precipitation [relative risk (RR)=1.145 per 1 g/m2/s (95% CI: 1.009, 1.300)] and lower daily mean temperature [RR=1.011 per 1°C change (1.000-1.021)] without carry-over effect to the next non-thunderstorm day. These higher risks were found mainly among children and adults <65 years of age. We observed similar results on lightning days. However, we did not find similar associations for non-thunderstorm or non-lightning days. Daily maximum O3 and PM2.5 levels were not significantly associated with asthma ED visits on thunderstorm days. DISCUSSION: Higher precipitation and lower temperature on thunderstorm days appear to contribute to asthma attacks among people with asthma, suggesting they should consider taking precautions during thunderstorms. EDs should consider preparing for a potential increase of asthma-related visits and ensuring sufficient stock of emergency medication and supplies for forecasted severe thunderstorm days. https://doi.org/10.1289/EHP10440.

Estimated N95 Respirator Needs for Nonhealthcare Essential Workers in the United States During Communicable Respiratory Infectious Disease Pandemics.

Early in the COVID-19 pandemic, demand for N95 respirators far exceeded the supply, leading to widespread shortages. Initially, the US Centers for Disease Control and Prevention did not recommend N95 respirators in nonhealthcare settings, in order to reserve them for healthcare workers. As N95s became more available, the recommendations were updated in May 2021 to include N95 respirators for nonhealthcare settings. In this study, we estimated the numbers of N95s needed for nonhealthcare essential workers in the United States. This information is valuable for crisis preparedness and planning for future large-scale communicable respiratory infectious disease epidemics or pandemics. We adapted a spreadsheet-based tool originally built to estimate the potential demand for N95 respirators during an influenza pandemic. We defined nonhealthcare essential occupations according to the 2020 US Department of Homeland Security guidance and used US Bureau of Labor Statistics employment numbers and Occupational Information Network data as model parameters. We modeled minimum, intermediate, and maximum N95 provision scenarios (as 1, 2, and 5 N95 respirators, respectively) per week per worker, for pandemic durations of 15 and 40 weeks. For 85.15 million nonhealthcare essential workers during a 15-week pandemic, an estimated 1.3 billion N95 respirators would be needed under minimum provision scenarios, 2.6 billion for intermediate provision, and 6.4 billion for maximum provision. During a 40-week pandemic, these estimates increased to 3.4 billion, 6.8 billion, and 17 billion. Public health authorities and policymakers can use these estimates when considering workplace respirator-wearing practices, including prioritization of allocation, for nonhealthcare essential workers. Our novel spreadsheet-based tool can also be used to quickly generate estimates of other preparedness and response equipment.

All causes of death among veterinarians in the United States during 1979 through 2015.

OBJECTIVE: To assess proportionate mortality from all causes for male and female US veterinarians during 1979 through 2015. SAMPLE: Death records for 11,620 veterinarians. PROCEDURES: For this proportionate mortality ratio (PMR) study, information for veterinarians who died during 1979 through 2015 was obtained from AVMA obituary and life insurance databases and submitted to a centralized database of US death records to obtain underlying causes of death. Decedent data that met records-matching criteria were imported into a software program for calculation of PMRs for all causes stratified by sex and indirectly standardized for age, race, and 5-year calendar period with 95% CIs. RESULTS: 11,620 decedents consisted of 11,049 (95%) males and 571 (5%) females with a median age at death of 77 years. Proportionate mortality for all veterinarian decedents was higher than expected for melanoma (PMRs, 2.1 and 2.2 for males and females, respectively), suicide (PMRs, 2.1 and 3.5 for males and females, respectively), and transportation injuries (PMRs, 1.7 and 1.6 for males and females, respectively). Proportionate mortality for all decedents was lower than expected for respiratory cancers (PMRs, 0.6 and 0.5 for males and females, respectively), diabetes mellitus (PMRs, 0.7 and 0.4 for males and females, respectively), heart disease (PMRs, 0.9 and 0.6 for males and females, respectively), and respiratory disorders (PMRs, 0.7 and 0.6 for males and females, respectively). CLINICAL RELEVANCE: Results indicated proportionate mortality from malignant melanoma, transportation injuries, and suicide for male and female veterinarians was higher than the general population. These data may help stakeholders improve veterinarian workplace safety and health guidelines.

CDC Deployments to State, Tribal, Local, and Territorial Health Departments for COVID-19 Emergency Public Health Response - United States, January 21-July 25, 2020.

Coronavirus disease 2019 (COVID-19) is a viral respiratory illness caused by SARS-CoV-2. During January 21-July 25, 2020, in response to official requests for assistance with COVID-19 emergency public health response activities, CDC deployed 208 teams to assist 55 state, tribal, local, and territorial health departments. CDC deployment data were analyzed to summarize activities by deployed CDC teams in assisting state, tribal, local, and territorial health departments to identify and implement measures to contain SARS-CoV-2 transmission (1). Deployed teams assisted with the investigation of transmission in high-risk congregate settings, such as long-term care facilities (53 deployments; 26% of total), food processing facilities (24; 12%), correctional facilities (12; 6%), and settings that provide services to persons experiencing homelessness (10; 5%). Among the 208 deployed teams, 178 (85%) provided assistance to state health departments, 12 (6%) to tribal health departments, 10 (5%) to local health departments, and eight (4%) to territorial health departments. CDC collaborations with health departments have strengthened local capacity and provided outbreak response support. Collaborations focused attention on health equity issues among disproportionately affected populations (e.g., racial and ethnic minority populations, essential frontline workers, and persons experiencing homelessness) and through a place-based focus (e.g., persons living in rural or frontier areas). These collaborations also facilitated enhanced characterization of COVID-19 epidemiology, directly contributing to CDC data-informed guidance, including guidance for serial testing as a containment strategy in high-risk congregate settings, targeted interventions and prevention efforts among workers at food processing facilities, and social distancing.

Spirometric Abnormalities and Lung Function Decline in Current and Former Microwave Popcorn and Current Flavoring Manufacturing Workers.

OBJECTIVE: The aim of this study was to compare spirometry results in microwave popcorn and flavoring manufacturing workers. METHODS: We used NIOSH data on current and former microwave popcorn workers (MPWs) and surveillance data on flavoring manufacturing workers (FMWs). RESULTS: Former MPW had higher prevalence of mixed and high severity abnormalities, some had excessive lung function drops. Current MPW had lowest occurrence of excessive lung function drops. FMW with excessive drops and spirometric abnormalities at last test had developed a restrictive pattern. Spirometric abnormalities and excessive drops were associated with work-related factors. CONCLUSION: There was evidence of a healthy worker survivor effect in MPW. Importantly, removal from exposure did not always stabilize lung function decline indicating a need for continued monitoring. The development of a restrictive pattern should raise the level of suspicion for possible work-related disease in flavoring-exposed workers.

The Burden of Respiratory Abnormalities Among Workers at Coffee Roasting and Packaging Facilities.

Introduction: Respiratory hazards in the coffee roasting and packaging industry can include asthmagens such as green coffee bean and other dust and alpha-diketones such as diacetyl and 2,3-pentanedione that can occur naturally from roasting coffee or artificially from addition of flavoring to coffee. We sought to describe the burden of respiratory abnormalities among workers at 17 coffee roasting and packaging facilities. Methods: We completed medical surveys at 17 coffee roasting and packaging facilities that included interviewer-administered questionnaires and pulmonary function testing. We summarized work-related symptoms, diagnoses, and spirometry testing results among all participants. We compared health outcomes between participants who worked near flavoring and who did not. Results: Participants most commonly reported nose and eye symptoms, and wheeze, with a work-related pattern for some. Symptoms and pulmonary function tests were consistent with work-related asthma in some participants. About 5% of workers had abnormal spirometry and most improved after bronchodilator. Health outcomes were similar between employees who worked near flavoring and who did not, except employees who worked near flavoring reported more chronic bronchitis and ever receiving a diagnosis of asthma than those who did not work near flavoring. Conclusion: The symptoms and patterns likely represent overlapping health effects of different respiratory hazards, including green coffee bean and other dust that can contribute to work-related asthma, and diacetyl and 2,3-pentanedione that can contribute to obliterative bronchiolitis. Healthcare providers and occupational health and safety practitioners should be aware that workers at coffee roasting and packaging facilities are potentially at risk for occupational lung diseases.

Suicide among veterinarians in the United States from 1979 through 2015.

OBJECTIVE To assess proportionate mortality ratios (PMRs) for suicide among male and female US veterinarians from 1979 through 2015. DESIGN PMR study. SAMPLE Death records for 11,620 veterinarians. PROCEDURES Information for veterinarians who died during 1979 through 2015 was obtained from AVMA obituary and life insurance databases and submitted to a centralized database of US death records to obtain underlying causes of death. Decedent data that met records-matching criteria were imported into a software program for calculation of PMRs for suicide stratified by sex and indirectly standardized for age, race, and 5-year calendar period with 95% confidence intervals. RESULTS 398 deaths resulted from suicide; 326 (82%) decedents were male, 72 (18%) were female, and most (298 [75%]) were ≤ 65 years of age. The PMRs for suicide for all veterinarian decedents (2.1 and 3.5 for males and females, respectively), those in clinical positions (2.2 and 3.4 for males and females, respectively), and those in nonclinical positions (1.8 and 5.0 for males and females, respectively) were significantly higher than for the general US population. Among female veterinarians, the percentage of deaths by suicide was stable from 2000 until the end of the study, but the number of such deaths subjectively increased with each 5-year period. CONCLUSIONS AND CLINICAL RELEVANCE Results of the study indicated that PMRs for suicide of female as well as male veterinarians were higher than for the general population. These data may help to inform stakeholders in the creation and implementation of suicide prevention strategies designed for veterinarians.

Burden of respiratory abnormalities in microwave popcorn and flavouring manufacturing workers.

OBJECTIVES: Diacetyl, a butter flavour compound used in food and flavouring production, is a respiratory toxin. We characterised the burden of respiratory abnormalities in workers at popcorn and flavouring manufacturing facilities that used diacetyl as evaluated through US National Institute for Occupational Safety and Health (NIOSH) health hazard evaluations. METHODS: We performed analyses describing the number and percentage of current and former workers from popcorn and flavouring manufacturing facilities where NIOSH administered a respiratory health questionnaire and spirometry testing who met case definitions of suspected flavouring-related lung disease. Case definitions were pathologist reported: lung biopsy pathology report stating supportive of/consistent with constrictive bronchiolitis or bronchiolitis obliterans; probable: obstructive/mixed spirometric pattern with forced expiratory volume in 1 s (FEV1) <60% predicted; possible: obstructive/mixed spirometric pattern with FEV1 ≥60% or any spirometric restriction; symptoms only: normal spirometry plus exertional dyspnoea or usual cough. RESULTS: During 2000-2012, NIOSH collected questionnaire and spirometry data on 1407 workers (87.0% current, 13.0% former) at nine facilities in eight states. After applying case definitions, 4 (0.3%) were classified as pathologist reported, 48 (3.4%) as probable, 234 (16.6%) as possible and 404 (28.7%) as symptoms only. The remaining 717 (51.0%) workers had normal spirometry without exertional dyspnoea or usual cough. Seven of 11 workers with biopsies did not meet the pathologist-reported case definition, although four met probable and three met possible. CONCLUSIONS: This approach demonstrates the substantial burden of respiratory abnormalities in these workers. A similar approach could quantify the burden of respiratory abnormalities in other industries that use diacetyl.

Acute Health Effects After the Elk River Chemical Spill, West Virginia, January 2014.

OBJECTIVES: On January 9, 2014, approximately 10 000 gallons of a mixture of 4-methylcyclohexanemethanol and propylene glycol phenyl ether spilled into West Virginia's Elk River, contaminating the potable water supply of about 300 000 West Virginia residents. This study sought to describe acute health effects after the chemical spill. METHODS: We conducted a descriptive analysis using 3 complementary data sources: (1) medical records of patients who visited an emergency department during January 9-23, 2014, with illness potentially related to the spill; (2) West Virginia Poison Center caller records coded as "contaminated water" during January 9-23, 2014; and (3) answers to household surveys about health effects from a Community Assessment for Public Health Emergency Response (CASPER) questionnaire administered 3 months after the spill. RESULTS: In the 2 weeks after the spill, 2000 people called the poison center reporting exposure to contaminated water, and 369 people visited emergency departments in the affected area with reports of exposure and symptoms potentially related to the spill. According to CASPER weighted cluster analyses, an estimated 25 623 households (21.7%; 95% confidence interval [CI], 14.4%-28.9%) had ≥1 person with symptoms who felt that they were related to the spill in the 3 months after it. Reported health effects across all 3 data sources included mild skin, respiratory, and gastrointestinal symptoms that resolved with no or minimal treatment. CONCLUSIONS: Medical records, poison center data, and CASPER household surveys were inexact but useful data sources to describe overall community health effects after a large-scale chemical spill. Analyzing multiple data sources could inform epidemiologic investigations of similar events.

Assessment of Impact and Recovery Needs in Communities Affected by the Elk River Chemical Spill, West Virginia, April 2014.

OBJECTIVES: In January 2014, 4-methylcyclohexanemethanol spilled into the Elk River near Charleston, West Virginia, contaminating the water supply for about 120 000 households. The West Virginia American Water Company (WVAWC) issued a "do not use" water order for 9 counties. After the order was lifted (10 days after the spill), the communities' use of public water systems, information sources, alternative sources of water, and perceived impact of the spill on households were unclear to public health officials. To assist in recovery efforts, the West Virginia Bureau for Public Health and the Centers for Disease Control and Prevention conducted a Community Assessment for Public Health Emergency Response (CASPER). METHODS: We used the CASPER 2-stage cluster sampling design to select a representative sample of households to interview, and we conducted interviews in 171 households in April 2014. We used a weighted cluster analysis to generate population estimates in the sampling frame. RESULTS: Before the spill, 74.4% of households did not have a 3-day alternative water supply for each household member and pet. Although 83.6% of households obtained an alternative water source within 1 day of the "do not use" order, 37.4% of households reportedly used WVAWC water for any purpose. Nearly 3 months after the spill, 36.1% of households believed that their WVAWC water was safe, and 33.5% reported using their household water for drinking. CONCLUSIONS: CASPER results identified the need to focus on basic public health messaging and household preparedness efforts. Recommendations included (1) encouraging households to maintain a 3-day emergency water supply, (2) identifying additional alternative sources of water for future emergencies, and (3) increasing community education to address ongoing concerns about water.

Research to Practice Implications of High-Risk Genotypes for Beryllium Sensitization and Disease.

OBJECTIVE: Beryllium workers may better understand their genetic susceptibility to chronic beryllium disease (CBD) expressed as population-based prevalence, rather than odds ratios from case-control studies. METHODS: We calculated CBD prevalences from allele-specific DNA sequences of 853 workers for Human Leukocyte Antigen (HLA)-DPB1 genotypes and groups characterized by number of E69-containing alleles and by calculated surface electronegativity of HLA-DPB1. RESULTS: Of 18 groups of at least 10 workers with specific genotypes, CBD prevalence was highest, 72.7%, for the HLA-DPB102:01:02/DPB117:01 genotype. Population-based grouped genotypes with two E69 alleles wherein one allele had -9 surface charge had a beryllium sensitization (BeS) of 52.6% and a CBD prevalence of 42.1%. CONCLUSIONS: The high CBD and BeS prevalences associated with -9-charged E69 alleles and two E69s suggest that workers may benefit from knowing their genetic susceptibility in deciding whether to avoid future beryllium exposure.

Melting barriers to faunal exchange across ocean basins.

Accelerated loss of sea ice in the Arctic is opening routes connecting the Atlantic and Pacific Oceans for longer periods each year. These changes may increase the ease and frequency with which marine birds and mammals move between the Pacific and Atlantic Ocean basins. Indeed, recent observations of birds and mammals suggest these movements have intensified in recent decades. Reconnection of the Pacific and Atlantic Ocean basins will present both challenges to marine ecosystem conservation and an unprecedented opportunity to examine the ecological and evolutionary consequences of interoceanic faunal exchange in real time. To understand these changes and implement effective conservation of marine ecosystems, we need to further develop modeling efforts to predict the rate of dispersal and consequences of faunal exchange. These predictions can be tested by closely monitoring wildlife dispersal through the Arctic Ocean and using modern methods to explore the ecological and evolutionary consequences of these movements.

Heat Stress Illness Emergency Department Visits in National Environmental Public Health Tracking States, 2005-2010.

Variability of heat stress illness (HSI) by urbanicity and climate region has rarely been considered in previous HSI studies. We investigated temporal and geographic trends in HSI emergency department (ED) visits in CDC Environmental Public Health Tracking Network (Tracking) states for 2005-2010. We obtained county-level HSI ED visit data for 14 Tracking states. We used the National Center for Health Statistics Urban-Rural Classification Scheme to categorize counties by urbanicity as (1) large central metropolitan (LCM), (2) large fringe metropolitan, (3) small-medium metropolitan, or (4) nonmetropolitan (NM). We also assigned counties to one of six US climate regions. Negative binomial regression was used to examine trends in HSI ED visits over time across all counties and by urbanicity for each climate region, adjusting for pertinent variables. During 2005-2010, there were 98,462 HSI ED visits in the 14 states. ED visits for HSI decreased 3.0% (p < 0.01) per year. Age-adjusted incidence rates of HSI ED visits increased from most urban to most rural. Overall, ED visits were significantly higher for NM areas (IRR = 1.41, p < 0.01) than for LCM areas. The same pattern was observed in all six climate regions; compared with LCM, NM areas had from 14 to 90% more ED visits for HSI. These findings of significantly increased HSI ED visit rates in more rural settings suggest a need to consider HSI ED visit variability by county urbanicity and climate region when designing and implementing local HSI preventive measures and interventions.

Monitoring of Persons with Risk for Exposure to Ebola Virus Disease - United States, November 3, 2014-March 8, 2015.

On October 27, 2014, CDC released guidance for monitoring and movement of persons with potential Ebola virus disease (Ebola) exposure in the United States. For persons with possible exposure to Ebola, this guidance recommended risk categorization, daily monitoring during the 21-day incubation period, and, for persons in selected risk categories, movement restrictions. The purpose of the guidance was to delineate methods for early identification of symptoms among persons at potential risk for Ebola so that they could be isolated, tested, and if necessary, treated to improve their chance of survival and reduce transmission. Within 7 days, all 50 states and two local jurisdictions (New York City [NYC] and the District of Columbia [DC]) had implemented the guidelines. During November 3, 2014-March 8, 2015, a total of 10,344 persons were monitored for up to 21 days with >99% complete monitoring. This public health response demonstrated the ability of state, territorial, and local health agencies to rapidly implement systems to effectively monitor thousands of persons over a sustained period.

Experimental and natural vertical transmission of West Nile virus by California Culex (Diptera: Culicidae) mosquitoes.

Culex (Diptera: Culicidae) mosquitoes, the primary summer vectors of West Nile virus (family Flaviviridae, genus Flavivirus, WNV), also may serve as overwintering reservoir hosts. Detection of WN viral RNA from larvae hatched from eggs deposited by infected females during late summer and fall may provide evidence for the vertical passage of WNV to overwintering cohorts. To determine whether vertical transmission to the overwintering generation occurs in populations of Culex mosquitoes throughout California, larvae from naturally infected females were tested by family for WN viral RNA by real-time quantitative reverse transcription-polymerase chain reaction during August through October 2011. Viral RNA was detected in 34 of 934 Culex tarsalis Coquillett and Cx. pipiens complex females that laid viable egg rafts. From these egg rafts, first-instar larvae from nine families tested positive, yielding an overall field vertical transmission rate of 26% (n = 34). To determine whether the WNV may be lost transtadially during development to the adult stage, first-instar larvae and adult progeny from experimentally infected Cx. pipiens complex females were assessed for the presence and quantity of WN viral RNA. Most (approximately 75%) WNV infections were lost from positive families during larval development to the adult stage. In field and laboratory studies, only infected mothers with mean cycle threshold scores < or = 20 vertically transmitted WNV to larval progeny, adult progeny, or both. In summary, vertical transmission of WNV was detected repeatedly in naturally infected Culex mosquitoes collected throughout California during late summer and fall, with females having high titered infections capable of passing WNV onto their progeny destined for overwintering.