Epidemic Intelligence Service Alumni in Public Health Leadership Roles.

Since 1951, the Epidemic Intelligence Service (EIS) of the U.S. Centers for Disease Control and Prevention (CDC) has trained physicians, nurses, scientists, veterinarians, and other allied health professionals in applied epidemiology. To understand the program's effect on graduates' leadership outcomes, we examined the EIS alumni representation in five select leadership positions. These positions were staffed by 353 individuals, of which 185 (52%) were EIS alumni. Among 12 CDC directors, four (33%) were EIS alumni. EIS alumni accounted for 29 (58%) of the 50 CDC center directors, 61 (35%) of the 175 state epidemiologists, 27 (56%) of the 48 Field Epidemiology Training Program resident advisors, and 70 (90%) of the 78 Career Epidemiology Field Officers. Of the 185 EIS alumni in leadership positions, 136 (74%) were physicians, 22 (12%) were scientists, 21 (11%) were veterinarians, 6 (3%) were nurses, and 94 (51%) were assigned to a state or local health department. Among the 61 EIS alumni who served as state epidemiologists, 40 (66%) of them were assigned to a state or local health department during EIS. Our evaluation suggests that epidemiology training programs can serve as a vital resource for the public health workforce, particularly given the capacity strains brought to light by the COVID-19 pandemic.

Coronavirus Disease Contact Tracing Outcomes and Cost, Salt Lake County, Utah, USA, March-May 2020.

Outcomes and costs of coronavirus disease (COVID-19) contact tracing are limited. During March-May 2020, we constructed transmission chains from 184 index cases and 1,499 contacts in Salt Lake County, Utah, USA, to assess outcomes and estimate staff time and salaries. We estimated 1,102 staff hours and $29,234 spent investigating index cases and contacts. Among contacts, 374 (25%) had COVID-19; secondary case detection rate was ≈31% among first-generation contacts, ≈16% among second- and third-generation contacts, and ≈12% among fourth-, fifth-, and sixth-generation contacts. At initial interview, 51% (187/370) of contacts were COVID-19-positive; 35% (98/277) became positive during 14-day quarantine. Median time from symptom onset to investigation was 7 days for index cases and 4 days for first-generation contacts. Contact tracing reduced the number of cases between contact generations and time between symptom onset and investigation but required substantial resources. Our findings can help jurisdictions allocate resources for contact tracing.

Household Transmission of Severe Acute Respiratory Syndrome Coronavirus-2 in the United States.

BACKGROUND: The evidence base for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is nascent. We sought to characterize SARS-CoV-2 transmission within US households and estimate the household secondary infection rate (SIR) to inform strategies to reduce transmission. METHODS: We recruited patients with laboratory-confirmed SARS-CoV-2 infection and their household contacts in Utah and Wisconsin during 22 March 2020-25 April 2020. We interviewed patients and all household contacts to obtain demographics and medical histories. At the initial household visit, 14 days later, and when a household contact became newly symptomatic, we collected respiratory swabs from patients and household contacts for testing by SARS-CoV-2 real-time reverse-transcription polymerase chain reaction (rRT-PCR) and sera for SARS-CoV-2 antibodies testing by enzyme-linked immunosorbent assay (ELISA). We estimated SIR and odds ratios (ORs) to assess risk factors for secondary infection, defined by a positive rRT-PCR or ELISA test. RESULTS: Thirty-two (55%) of 58 households secondary infection among household contacts. The SIR was 29% (n = 55/188; 95% confidence interval [CI], 23%-36%) overall, 42% among children (aged <18 years) of the COVID-19 patient and 33% among spouses/partners. Household contacts to COVID-19 patients with immunocompromised conditions and household contacts who themselves had diabetes mellitus had increased odds of infection with ORs 15.9 (95% CI, 2.4-106.9) and 7.1 (95% CI: 1.2-42.5), respectively. CONCLUSIONS: We found substantial evidence of secondary infections among household contacts. People with COVID-19, particularly those with immunocompromising conditions or those with household contacts with diabetes, should take care to promptly self-isolate to prevent household transmission.

A Prospective Cohort Study in Nonhospitalized Household Contacts With Severe Acute Respiratory Syndrome Coronavirus 2 Infection: Symptom Profiles and Symptom Change Over Time.

BACKGROUND: Improved understanding of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spectrum of disease is essential for clinical and public health interventions. There are limited data on mild or asymptomatic infections, but recognition of these individuals is key as they contribute to viral transmission. We describe the symptom profiles from individuals with mild or asymptomatic SARS-CoV-2 infection. METHODS: From 22 March to 22 April 2020 in Wisconsin and Utah, we enrolled and prospectively observed 198 household contacts exposed to SARS-CoV-2. We collected and tested nasopharyngeal specimens by real-time reverse-transcription polymerase chain reaction (rRT-PCR) 2 or more times during a 14-day period. Contacts completed daily symptom diaries. We characterized symptom profiles on the date of first positive rRT-PCR test and described progression of symptoms over time. RESULTS: We identified 47 contacts, median age 24 (3-75) years, with detectable SARS-CoV-2 by rRT-PCR. The most commonly reported symptoms on the day of first positive rRT-PCR test were upper respiratory (n = 32 [68%]) and neurologic (n = 30 [64%]); fever was not commonly reported (n = 9 [19%]). Eight (17%) individuals were asymptomatic at the date of first positive rRT-PCR collection; 2 (4%) had preceding symptoms that resolved and 6 (13%) subsequently developed symptoms. Children less frequently reported lower respiratory symptoms (21%, 60%, and 69% for <18, 18-49, and ≥50 years of age, respectively; P = .03). CONCLUSIONS: Household contacts with laboratory-confirmed SARS-CoV-2 infection reported mild symptoms. When assessed at a single timepoint, several contacts appeared to have asymptomatic infection; however, over time all developed symptoms. These findings are important to inform infection control, contact tracing, and community mitigation strategies.

Opening of Large Institutions of Higher Education and County-Level COVID-19 Incidence - United States, July 6-September 17, 2020.

During early August 2020, county-level incidence of coronavirus disease 2019 (COVID-19) generally decreased across the United States, compared with incidence earlier in the summer (1); however, among young adults aged 18-22 years, incidence increased (2). Increases in incidence among adults aged ≥60 years, who might be more susceptible to severe COVID-19-related illness, have followed increases in younger adults (aged 20-39 years) by an average of 8.7 days (3). Institutions of higher education (colleges and universities) have been identified as settings where incidence among young adults increased during August (4,5). Understanding the extent to which these settings have affected county-level COVID-19 incidence can inform ongoing college and university operations and future planning. To evaluate the effect of large colleges or universities and school instructional format* (remote or in-person) on COVID-19 incidence, start dates and instructional formats for the fall 2020 semester were identified for all not-for-profit large U.S. colleges and universities (≥20,000 total enrolled students). Among counties with large colleges and universities (university counties) included in the analysis, remote-instruction university counties (22) experienced a 17.9% decline in mean COVID-19 incidence during the 21 days before through 21 days after the start of classes (from 17.9 to 14.7 cases per 100,000), and in-person instruction university counties (79) experienced a 56.2% increase in COVID-19 incidence, from 15.3 to 23.9 cases per 100,000. Counties without large colleges and universities (nonuniversity counties) (3,009) experienced a 5.9% decline in COVID-19 incidence, from 15.3 to 14.4 cases per 100,000. Similar findings were observed for percentage of positive test results and hotspot status (i.e., increasing among in-person-instruction university counties). In-person instruction at colleges and universities was associated with increased county-level COVID-19 incidence and percentage test positivity. Implementation of increased mitigation efforts at colleges and universities could minimize on-campus COVID-19 transmission.

Declines in SARS-CoV-2 Transmission, Hospitalizations, and Mortality After Implementation of Mitigation Measures- Delaware, March-June 2020.

Mitigation measures, including stay-at-home orders and public mask wearing, together with routine public health interventions such as case investigation with contact tracing and immediate self-quarantine after exposure, are recommended to prevent and control the transmission of SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19) (1-3). On March 11, the first COVID-19 case in Delaware was reported to the Delaware Division of Public Health (DPH). The state responded to ongoing community transmission with investigation of all identified cases (commencing March 11), issuance of statewide stay-at-home orders (March 24-June 1), a statewide public mask mandate (from April 28), and contact tracing (starting May 12). The relationship among implementation of mitigation strategies, case investigations, and contact tracing and COVID-19 incidence and associated hospitalization and mortality was examined during March-June 2020. Incidence declined by 82%, hospitalization by 88%, and mortality by 100% from late April to June 2020, as the mask mandate and contact tracing were added to case investigations and the stay-at-home order. Among 9,762 laboratory-confirmed COVID-19 cases reported during March 11-June 25, 2020, two thirds (6,527; 67%) of patients were interviewed, and 5,823 (60%) reported completing isolation. Among 2,834 contacts reported, 882 (31%) were interviewed and among these contacts, 721 (82%) reported completing quarantine. Implementation of mitigation measures, including mandated mask use coupled with public health interventions, was followed by reductions in COVID-19 incidence and associated hospitalizations and mortality. The combination of state-mandated community mitigation efforts and routine public health interventions can reduce the occurrence of new COVID-19 cases, hospitalizations, and deaths.

Detection of SARS-CoV-2 on Surfaces in Households of Persons with COVID-19.

SARS-CoV-2 transmission from contaminated surfaces, or fomites, has been a concern during the COVID-19 pandemic. Households have been important sites of transmission throughout the COVID-19 pandemic, but there is limited information on SARS-CoV-2 contamination of surfaces in these settings. We describe environmental detection of SARS-CoV-2 in households of persons with COVID-19 to better characterize the potential risks of fomite transmission. Ten households with ≥1 person with laboratory-confirmed COVID-19 and with ≥2 members total were enrolled in Utah, U.S.A. Nasopharyngeal and anterior nasal swabs were collected from members and tested for the presence of SARS-CoV-2 by RT-PCR. Fifteen surfaces were sampled in each household and tested for presence and viability of SARS-CoV-2. SARS-CoV-2 RNA was detected in 23 (15%) of 150 environmental swab samples, most frequently on nightstands (4/6; 67%), pillows (4/23; 17%), and light switches (3/21; 14%). Viable SARS-CoV-2 was cultured from one sample. All households with SARS-CoV-2-positive surfaces had ≥1 person who first tested positive for SARS-CoV-2 ≤ 6 days prior to environmental sampling. SARS-CoV-2 surface contamination occurred early in the course of infection when respiratory transmission is most likely, notably on surfaces in close, prolonged contact with persons with COVID-19. While fomite transmission might be possible, risk is low.

Epidemiological Correlates of Polymerase Chain Reaction Cycle Threshold Values in the Detection of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2).

BACKGROUND: Detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has principally been performed through the use of real-time reverse-transcription polymerase chain reaction testing. Results of such tests can be reported as cycle threshold (Ct) values, which may provide semi-quantitative or indirect measurements of viral load. Previous reports have examined temporal trends in Ct values over the course of a SARS-CoV-2 infection. METHODS: Using testing data collected during a prospective household transmission investigation of outpatient and mild coronavirus disease 2019 cases, we examined the relationships between Ct values of the viral RNA N1 target and demographic, clinical, and epidemiological characteristics collected through participant interviews and daily symptom diaries. RESULTS: We found that Ct values are lowest (corresponding to a higher viral RNA concentration) soon after symptom onset and are significantly correlated with the time elapsed since onset (P < .001); within 7 days after symptom onset, the median Ct value was 26.5, compared with a median Ct value of 35.0 occurring 21 days after onset. Ct values were significantly lower among participants under 18 years of age (P = .01) and those reporting upper respiratory symptoms at the time of sample collection (P = .001), and were higher among participants reporting no symptoms (P = .05). CONCLUSIONS: These results emphasize the importance of early testing for SARS-CoV-2 among individuals with symptoms of respiratory illness, and allow cases to be identified and isolated when their viral shedding may be highest.

Association Between Social Vulnerability and a County's Risk for Becoming a COVID-19 Hotspot - United States, June 1-July 25, 2020.

Poverty, crowded housing, and other community attributes associated with social vulnerability increase a community's risk for adverse health outcomes during and following a public health event (1). CDC uses standard criteria to identify U.S. counties with rapidly increasing coronavirus disease 2019 (COVID-19) incidence (hotspot counties) to support health departments in coordinating public health responses (2). County-level data on COVID-19 cases during June 1-July 25, 2020 and from the 2018 CDC social vulnerability index (SVI) were analyzed to examine associations between social vulnerability and hotspot detection and to describe incidence after hotspot detection. Areas with greater social vulnerabilities, particularly those related to higher representation of racial and ethnic minority residents (risk ratio [RR] = 5.3; 95% confidence interval [CI] = 4.4-6.4), density of housing units per structure (RR = 3.1; 95% CI = 2.7-3.6), and crowded housing units (i.e., more persons than rooms) (RR = 2.0; 95% CI = 1.8-2.3), were more likely to become hotspots, especially in less urban areas. Among hotspot counties, those with greater social vulnerability had higher COVID-19 incidence during the 14 days after detection (212-234 cases per 100,000 persons for highest SVI quartile versus 35-131 cases per 100,000 persons for other quartiles). Focused public health action at the federal, state, and local levels is needed not only to prevent communities with greater social vulnerability from becoming hotspots but also to decrease persistently high incidence among hotspot counties that are socially vulnerable.

Symptoms and Transmission of SARS-CoV-2 Among Children - Utah and Wisconsin, March-May 2020.

BACKGROUND AND OBJECTIVES: Limited data exist on severe acute respiratory syndrome coronavirus 2 in children. We described infection rates and symptom profiles among pediatric household contacts of individuals with coronavirus disease 2019. METHODS: We enrolled individuals with coronavirus disease 2019 and their household contacts, assessed daily symptoms prospectively for 14 days, and obtained specimens for severe acute respiratory syndrome coronavirus 2 real-time reverse transcription polymerase chain reaction and serology testing. Among pediatric contacts (<18 years), we described transmission, assessed the risk factors for infection, and calculated symptom positive and negative predictive values. We compared secondary infection rates and symptoms between pediatric and adult contacts using generalized estimating equations. RESULTS: Among 58 households, 188 contacts were enrolled (120 adults; 68 children). Secondary infection rates for adults (30%) and children (28%) were similar. Among households with potential for transmission from children, child-to-adult transmission may have occurred in 2 of 10 (20%), and child-to-child transmission may have occurred in 1 of 6 (17%). Pediatric case patients most commonly reported headache (79%), sore throat (68%), and rhinorrhea (68%); symptoms had low positive predictive values, except measured fever (100%; 95% confidence interval [CI]: 44% to 100%). Compared with symptomatic adults, children were less likely to report cough (odds ratio [OR]: 0.15; 95% CI: 0.04 to 0.57), loss of taste (OR: 0.21; 95% CI: 0.06 to 0.74), and loss of smell (OR: 0.29; 95% CI: 0.09 to 0.96) and more likely to report sore throat (OR: 3.4; 95% CI: 1.04 to 11.18). CONCLUSIONS: Children and adults had similar secondary infection rates, but children generally had less frequent and severe symptoms. In two states early in the pandemic, we observed possible transmission from children in approximately one-fifth of households with potential to observe such transmission patterns.