Public health impact of the U.S. Scenario Modeling Hub.

Beginning in December 2020, the COVID-19 Scenario Modeling Hub has provided quantitative scenario-based projections for cases, hospitalizations, and deaths, aggregated across up to nine modeling groups. Projections spanned multiple months into the future and provided timely information on potential impacts of epidemiological uncertainties and interventions. Projections results were shared with the public, public health partners, and the Centers for Disease Control COVID-19 Response Team. The projections provided insights on situational awareness and informed decision-making to mitigate COVID-19 disease burden (e.g., vaccination strategies). By aggregating projections from multiple modeling teams, the Scenario Modeling Hub provided rapidly synthesized information in times of great uncertainty and conveyed possible trajectories in the presence of emerging variants. Here we detail several use cases of these projections in public health practice and communication, including assessments of whether modeling results directly or indirectly informed public health communication or guidance. These include multiple examples where comparisons of projected COVID-19 disease outcomes under different vaccination scenarios were used to inform Advisory Committee for Immunization Practices recommendations. We also describe challenges and lessons learned during this highly beneficial collaboration.

Point Prevalence Estimates of Activity-Limiting Long-term Symptoms Among United States Adults ≥1 Month After Reported Severe Acute Respiratory Syndrome Coronavirus 2 Infection, 1 November 2021.

BACKGROUND: Although most adults infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) fully recover, a proportion have ongoing symptoms, or post-COVID conditions (PCC), after infection. The objective of this analysis was to estimate the number of United States (US) adults with activity-limiting PCC on 1 November 2021. METHODS: We modeled the prevalence of PCC using reported infections occurring from 1 February 2020 to 30 September 2021, and population-based, household survey data on new activity-limiting symptoms ≥1 month following SARS-CoV-2 infection. From these data sources, we estimated the number and proportion of US adults with activity-limiting PCC on 1 November 2021 as 95% uncertainty intervals, stratified by sex and age. Sensitivity analyses adjusted for underascertainment of infections and uncertainty about symptom duration. RESULTS: On 1 November 2021, at least 3.0-5.0 million US adults, or 1.2%-1.9% of the US adult population, were estimated to have activity-limiting PCC of ≥1 month's duration. Population prevalence was higher in females (1.4%-2.2%) than males. The estimated prevalence after adjusting for underascertainment of infections was 1.7%-3.8%. CONCLUSIONS: Millions of US adults were estimated to have activity-limiting PCC. These estimates can support future efforts to address the impact of PCC on the US population.

Estimated Number of COVID-19 Infections, Hospitalizations, and Deaths Prevented Among Vaccinated Persons in the US, December 2020 to September 2021.

Importance: The number of SARS-CoV-2 infections and COVID-19-associated hospitalizations and deaths prevented among vaccinated persons, independent of the effect of reduced transmission, is a key measure of vaccine impact. Objective: To estimate the number of SARS-CoV-2 infections and COVID-19-associated hospitalizations and deaths prevented among vaccinated adults in the US. Design, Setting, and Participants: In this modeling study, a multiplier model was used to extrapolate the number of SARS-CoV-2 infections and COVID-19-associated deaths from data on the number of COVID-19-associated hospitalizations stratified by state, month, and age group (18-49, 50-64, and ≥65 years) in the US from December 1, 2020, to September 30, 2021. These estimates were combined with data on vaccine coverage and effectiveness to estimate the risks of infections, hospitalizations, and deaths. Risks were applied to the US population 18 years or older to estimate the expected burden in that population without vaccination. The estimated burden in the US population 18 years or older given observed levels of vaccination was subtracted from the expected burden in the US population 18 years or older without vaccination (ie, counterfactual) to estimate the impact of vaccination among vaccinated persons. Exposures: Completion of the COVID-19 vaccination course, defined as 2 doses of messenger RNA (BNT162b2 or mRNA-1273) vaccines or 1 dose of JNJ-78436735 vaccine. Main Outcomes and Measures: Monthly numbers and percentages of SARS-CoV-2 infections and COVID-19-associated hospitalizations and deaths prevented were estimated among those who have been vaccinated in the US. Results: COVID-19 vaccination was estimated to prevent approximately 27 million (95% uncertainty interval [UI], 22 million to 34 million) infections, 1.6 million (95% UI, 1.4 million to 1.8 million) hospitalizations, and 235 000 (95% UI, 175 000-305 000) deaths in the US from December 1, 2020, to September 30, 2021, among vaccinated adults 18 years or older. From September 1 to September 30, 2021, vaccination was estimated to prevent 52% (95% UI, 45%-62%) of expected infections, 56% (95% UI, 52%-62%) of expected hospitalizations, and 58% (95% UI, 53%-63%) of expected deaths in adults 18 years or older. Conclusions and Relevance: These findings indicate that the US COVID-19 vaccination program prevented a substantial burden of morbidity and mortality through direct protection of vaccinated individuals.

Genomic Surveillance for SARS-CoV-2 Variants: Predominance of the Delta (B.1.617.2) and Omicron (B.1.1.529) Variants - United States, June 2021-January 2022.

Genomic surveillance is a critical tool for tracking emerging variants of SARS-CoV-2 (the virus that causes COVID-19), which can exhibit characteristics that potentially affect public health and clinical interventions, including increased transmissibility, illness severity, and capacity for immune escape. During June 2021-January 2022, CDC expanded genomic surveillance data sources to incorporate sequence data from public repositories to produce weighted estimates of variant proportions at the jurisdiction level and refined analytic methods to enhance the timeliness and accuracy of national and regional variant proportion estimates. These changes also allowed for more comprehensive variant proportion estimation at the jurisdictional level (i.e., U.S. state, district, territory, and freely associated state). The data in this report are a summary of findings of recent proportions of circulating variants that are updated weekly on CDC's COVID Data Tracker website to enable timely public health action.† The SARS-CoV-2 Delta (B.1.617.2 and AY sublineages) variant rose from 1% to >50% of viral lineages circulating nationally during 8 weeks, from May 1-June 26, 2021. Delta-associated infections remained predominant until being rapidly overtaken by infections associated with the Omicron (B.1.1.529 and BA sublineages) variant in December 2021, when Omicron increased from 1% to >50% of circulating viral lineages during a 2-week period. As of the week ending January 22, 2022, Omicron was estimated to account for 99.2% (95% CI = 99.0%-99.5%) of SARS-CoV-2 infections nationwide, and Delta for 0.7% (95% CI = 0.5%-1.0%). The dynamic landscape of SARS-CoV-2 variants in 2021, including Delta- and Omicron-driven resurgences of SARS-CoV-2 transmission across the United States, underscores the importance of robust genomic surveillance efforts to inform public health planning and practice.

COVID-19 Incidence and Death Rates Among Unvaccinated and Fully Vaccinated Adults with and Without Booster Doses During Periods of Delta and Omicron Variant Emergence - 25 U.S. Jurisdictions, April 4-December 25, 2021.

Previous reports of COVID-19 case, hospitalization, and death rates by vaccination status† indicate that vaccine protection against infection, as well as serious COVID-19 illness for some groups, declined with the emergence of the B.1.617.2 (Delta) variant of SARS-CoV-2, the virus that causes COVID-19, and waning of vaccine-induced immunity (1-4). During August-November 2021, CDC recommended§ additional primary COVID-19 vaccine doses among immunocompromised persons and booster doses among persons aged ≥18 years (5). The SARS-CoV-2 B.1.1.529 (Omicron) variant emerged in the United States during December 2021 (6) and by December 25 accounted for 72% of sequenced lineages (7). To assess the impact of full vaccination with additional and booster doses (booster doses),¶ case and death rates and incidence rate ratios (IRRs) were estimated among unvaccinated and fully vaccinated adults by receipt of booster doses during pre-Delta (April-May 2021), Delta emergence (June 2021), Delta predominance (July-November 2021), and Omicron emergence (December 2021) periods in the United States. During 2021, averaged weekly, age-standardized case IRRs among unvaccinated persons compared with fully vaccinated persons decreased from 13.9 pre-Delta to 8.7 as Delta emerged, and to 5.1 during the period of Delta predominance. During October-November, unvaccinated persons had 13.9 and 53.2 times the risks for infection and COVID-19-associated death, respectively, compared with fully vaccinated persons who received booster doses, and 4.0 and 12.7 times the risks compared with fully vaccinated persons without booster doses. When the Omicron variant emerged during December 2021, case IRRs decreased to 4.9 for fully vaccinated persons with booster doses and 2.8 for those without booster doses, relative to October-November 2021. The highest impact of booster doses against infection and death compared with full vaccination without booster doses was recorded among persons aged 50-64 and ≥65 years. Eligible persons should stay up to date with COVID-19 vaccinations.

Monitoring Incidence of COVID-19 Cases, Hospitalizations, and Deaths, by Vaccination Status - 13 U.S. Jurisdictions, April 4-July 17, 2021.

COVID-19 vaccine breakthrough infection surveillance helps monitor trends in disease incidence and severe outcomes in fully vaccinated persons, including the impact of the highly transmissible B.1.617.2 (Delta) variant of SARS-CoV-2, the virus that causes COVID-19. Reported COVID-19 cases, hospitalizations, and deaths occurring among persons aged ≥18 years during April 4-July 17, 2021, were analyzed by vaccination status across 13 U.S. jurisdictions that routinely linked case surveillance and immunization registry data. Averaged weekly, age-standardized incidence rate ratios (IRRs) for cases among persons who were not fully vaccinated compared with those among fully vaccinated persons decreased from 11.1 (95% confidence interval [CI] = 7.8-15.8) to 4.6 (95% CI = 2.5-8.5) between two periods when prevalence of the Delta variant was lower (<50% of sequenced isolates; April 4-June 19) and higher (≥50%; June 20-July 17), and IRRs for hospitalizations and deaths decreased between the same two periods, from 13.3 (95% CI = 11.3-15.6) to 10.4 (95% CI = 8.1-13.3) and from 16.6 (95% CI = 13.5-20.4) to 11.3 (95% CI = 9.1-13.9). Findings were consistent with a potential decline in vaccine protection against confirmed SARS-CoV-2 infection and continued strong protection against COVID-19-associated hospitalization and death. Getting vaccinated protects against severe illness from COVID-19, including the Delta variant, and monitoring COVID-19 incidence by vaccination status might provide early signals of changes in vaccine-related protection that can be confirmed through well-controlled vaccine effectiveness (VE) studies.

COVID-19 Vaccination Coverage Among Adults - United States, December 14, 2020-May 22, 2021.

The U.S. COVID-19 vaccination program launched on December 14, 2020. The Advisory Committee on Immunization Practices recommended prioritizing COVID-19 vaccination for specific groups of the U.S. population who were at highest risk for COVID-19 hospitalization and death, including adults aged ≥75 years*; implementation varied by state, and eligibility was gradually expanded to persons aged ≥65 years beginning in January 2021. By April 19, 2021, eligibility was expanded to all adults aged ≥18 years nationwide.† To assess patterns of COVID-19 vaccination coverage among U.S. adults, CDC analyzed data submitted on vaccinations administered during December 14, 2020-May 22, 2021, by age, sex, and community-level characteristics. By May 22, 2021, 57.0% of persons aged ≥18 years had received ≥1 COVID-19 vaccine dose; coverage was highest among persons aged ≥65 years (80.0%) and lowest among persons aged 18-29 years (38.3%). During the week beginning February 7, 2021, vaccination initiation among adults aged ≥65 years peaked at 8.2%, whereas weekly initiation among other age groups peaked later and at lower levels. During April 19-May 22, 2021, the period following expanded eligibility to all adults, weekly initiation remained <4.0% and decreased for all age groups, including persons aged 18-29 years (3.6% to 1.9%) and 30-49 years (3.5% to 1.7%); based on the current rate of weekly initiation (as of May 22), younger persons will not reach the same levels of coverage as older persons by the end of August. Across all age groups, coverage (≥1 dose) was lower among men compared with women, except among adults aged ≥65 years, and lower among persons living in counties that were less urban, had higher social vulnerabilities, or had higher percentages of social determinants of poor health. Continued efforts to improve vaccination confidence and alleviate barriers to vaccination initiation, especially among adults aged 18-49 years, could improve vaccination coverage.

Patterns in COVID-19 Vaccination Coverage, by Social Vulnerability and Urbanicity - United States, December 14, 2020-May 1, 2021.

Disparities in vaccination coverage by social vulnerability, defined as social and structural factors associated with adverse health outcomes, were noted during the first 2.5 months of the U.S. COVID-19 vaccination campaign, which began during mid-December 2020 (1). As vaccine eligibility and availability continue to expand, assuring equitable coverage for disproportionately affected communities remains a priority. CDC examined COVID-19 vaccine administration and 2018 CDC social vulnerability index (SVI) data to ascertain whether inequities in COVID-19 vaccination coverage with respect to county-level SVI have persisted, overall and by urbanicity. Vaccination coverage was defined as the number of persons aged ≥18 years (adults) who had received ≥1 dose of any Food and Drug Administration (FDA)-authorized COVID-19 vaccine divided by the total adult population in a specified SVI category.† SVI was examined overall and by its four themes (socioeconomic status, household composition and disability, racial/ethnic minority status and language, and housing type and transportation). Counties were categorized into SVI quartiles, in which quartile 1 (Q1) represented the lowest level of vulnerability and quartile 4 (Q4), the highest. Trends in vaccination coverage were assessed by SVI quartile and urbanicity, which was categorized as large central metropolitan, large fringe metropolitan (areas surrounding large cities, e.g., suburban), medium and small metropolitan, and nonmetropolitan counties.§ During December 14, 2020-May 1, 2021, disparities in vaccination coverage by SVI increased, especially in large fringe metropolitan (e.g., suburban) and nonmetropolitan counties. By May 1, 2021, vaccination coverage was lower among adults living in counties with the highest overall SVI; differences were most pronounced in large fringe metropolitan (Q4 coverage = 45.0% versus Q1 coverage = 61.7%) and nonmetropolitan (Q4 = 40.6% versus Q1 = 52.9%) counties. Vaccination coverage disparities were largest for two SVI themes: socioeconomic status (Q4 = 44.3% versus Q1 = 61.0%) and household composition and disability (Q4 = 42.0% versus Q1 = 60.1%). Outreach efforts, including expanding public health messaging tailored to local populations and increasing vaccination access, could help increase vaccination coverage in high-SVI counties.

Disparities in COVID-19 Vaccination Coverage Between Urban and Rural Counties - United States, December 14, 2020-April 10, 2021.

Approximately 60 million persons in the United States live in rural counties, representing almost one fifth (19.3%) of the population.* In September 2020, COVID-19 incidence (cases per 100,000 population) in rural counties surpassed that in urban counties (1). Rural communities often have a higher proportion of residents who lack health insurance, live with comorbidities or disabilities, are aged ≥65 years, and have limited access to health care facilities with intensive care capabilities, which places these residents at increased risk for COVID-19-associated morbidity and mortality (2,3). To better understand COVID-19 vaccination disparities across the urban-rural continuum, CDC analyzed county-level vaccine administration data among adults aged ≥18 years who received their first dose of either the Pfizer-BioNTech or Moderna COVID-19 vaccine, or a single dose of the Janssen COVID-19 vaccine (Johnson & Johnson) during December 14, 2020-April 10, 2021 in 50 U.S. jurisdictions (49 states and the District of Columbia [DC]). Adult COVID-19 vaccination coverage was lower in rural counties (38.9%) than in urban counties (45.7%) overall and among adults aged 18-64 years (29.1% rural, 37.7% urban), those aged ≥65 years (67.6% rural, 76.1% urban), women (41.7% rural, 48.4% urban), and men (35.3% rural, 41.9% urban). Vaccination coverage varied among jurisdictions: 36 jurisdictions had higher coverage in urban counties, five had higher coverage in rural counties, and five had similar coverage (i.e., within 1%) in urban and rural counties; in four jurisdictions with no rural counties, the urban-rural comparison could not be assessed. A larger proportion of persons in the most rural counties (14.6%) traveled for vaccination to nonadjacent counties (i.e., farther from their county of residence) compared with persons in the most urban counties (10.3%). As availability of COVID-19 vaccines expands, public health practitioners should continue collaborating with health care providers, pharmacies, employers, faith leaders, and other community partners to identify and address barriers to COVID-19 vaccination in rural areas (2).

Benchmarks for HIV Testing: What Is Needed to Achieve Universal Testing Coverage at U.S. Ambulatory Healthcare Facilities.

BACKGROUND: Black and Hispanic men have the highest rates of HIV diagnoses. To decrease the number of U.S. men who are unaware of their HIV status, they should be tested at least once. Our objective was to estimate the increases needed in HIV testing rates at ambulatory health care visits to achieve universal coverage. METHODS: We analyzed nationally representative medical record abstraction data to estimate the number of visits per person to physician offices, emergency departments, and outpatient clinics among men aged 18-39 years during 2009-2016, and the percentage of visits with an HIV test. We calculated the increase in the percentage of visits with an HIV test needed to achieve universal testing coverage of men by age 39 years. RESULTS: Men had a mean of 75.3 million ambulatory visits per year and 1.67 visits per person. An HIV test was performed at 0.9% of the ambulatory visits made by white men, 2.5% by black men, and 2.4% by Hispanic men. A 3-fold increase in the percentage of visits with an HIV test would result in coverage of 46.2% of white, 100% of black, and 100% of Hispanic men; an 11-fold increase would be needed to result in coverage of 100% of white men. CONCLUSIONS: HIV testing rates of men at ambulatory health care visits were too low to provide HIV testing coverage of all men by aged 39 years. A 3-fold increase in the percentage of visits with an HIV test would result in universal testing coverage of black and Hispanic men by age 39 years.

Estimating the impact of HIV combination prevention in men who have sex with men, the Bangkok MSM Cohort Study, Thailand.

In Thailand, pre-exposure prophylaxis (PrEP) is recommended for human immunodeficiency virus (HIV) prevention among at-risk men who have sex with men (MSM). We modeled the impact of PrEP and condom use as independent and combined interventions on the estimated number of HIV infections among a hypothetical population of 10,000 MSM in Bangkok, Thailand. Our model demonstrated a 92% (95% confidence interval 89.7, 94.2) reduction in HIV infections among Thai MSM who took daily PrEP and self-reported using condoms correctly and consistently (100% condom use). Increased use of PrEP and condoms likely would have a substantial impact on the HIV epidemic in Thailand.

Testing the Effectiveness and Cost-Effectiveness of a Combination HIV Prevention Intervention Among Young Cisgender Men Who Have Sex With Men and Transgender Women Who Sell or Exchange Sex in Thailand: Protocol for the Combination Prevention Effectiveness Study.

BACKGROUND: Pre-exposure prophylaxis (PrEP) is highly effective in the prevention of HIV acquisition, particularly for men who have sex with men (MSM). Questions remain on the benefits of PrEP and implementation strategies for those at occupational risk of HIV acquisition in sex work, as well as on methods to support adherence among young people who initiate PrEP. OBJECTIVE: The Combination Prevention Effectiveness study for young cisgender MSM and transgender women (TGW) aims to assess the effectiveness and cost-effectiveness of a combination intervention among HIV-uninfected young MSM and TGW engaged in sex work in Thailand. METHODS: This open-label, nonrandomized assessment compares the relative effectiveness of a combination prevention intervention with and without daily oral emtricitabine and tenofovir disoproxil fumarate (Truvada) PrEP with SMS-based adherence support. HIV-uninfected young MSM and TGW aged 18 to 26 years in Bangkok and Pattaya who self-report selling/exchanging sex at least once in the previous 12 months are recruited by convenience sampling and peer referral and are eligible regardless of their intent to initiate PrEP. At baseline, participants complete a standard assessment for PrEP eligibility and may initiate PrEP then or at any time during study participation. All participants complete a survey and HIV testing at baseline and every 3 months. Participants who initiate PrEP complete monthly pill pickups and may opt-in to SMS reminders. All participants are sent brief weekly SMS surveys to assess behavior with additional adherence questions for those who initiated PrEP. Adherence is defined as use of 4 or more pills within the last 7 days. The analytic plan uses a person-time approach to assess HIV incidence, comparing participant time on oral PrEP to participant time off oral PrEP for 12 to 24 months of follow-up, using a propensity score to control for confounders. Enrollment is based on the goal of observing 620 person-years (PY) on PrEP and 620 PY off PrEP. RESULTS: As of February 2019, 445 participants (417 MSM and 28 TGW) have contributed approximately 168 PY with 95% (73/77) retention at 12 months. 74.2% (330/445) of enrolled participants initiated PrEP at baseline, contributing to 134 PY of PrEP adherence, 1 PY nonadherence, and 33 PY PrEP nonuse/noninitiation. Some social harms, predominantly related to unintentional participant disclosure of PrEP use and peer stigmatization of PrEP and HIV, have been identified. CONCLUSIONS: The majority of cisgender MSM and TGW who exchange sex and participate in this study are interested in PrEP, report taking sufficient PrEP, and stay on PrEP, though additional efforts are needed to address community misinformation and stigma. This novel multilevel, open-label study design and person-time approach will allow evaluation of the effectiveness and cost-effectiveness of combination prevention intervention in the contexts of both organized sex work and exchanged sex. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR1-10.2196/15354.

Evidence of an Association of Increases in Pre-exposure Prophylaxis Coverage With Decreases in Human Immunodeficiency Virus Diagnosis Rates in the United States, 2012-2016.

BACKGROUND: Annual human immunodeficiency virus (HIV) diagnoses in the United States (US) have plateaued since 2013. We assessed whether there is an association between uptake of pre-exposure prophylaxis (PrEP) and decreases in HIV diagnoses. METHODS: We used 2012-2016 data from the US National HIV Surveillance System to estimate viral suppression (VS) and annual percentage change in diagnosis rate (EAPC) in 33 jurisdictions, and data from a national pharmacy database to estimate PrEP uptake. We used Poisson regression with random effects for state and year to estimate the association between PrEP coverage and EAPC: within jurisdictional quintiles grouped by changes in PrEP coverage, regressing EAPC on time; and among all jurisdictions, regressing EAPC on both time and jurisdictional changes in PrEP coverage with and without accounting for changes in VS. RESULTS: From 2012 to 2016, across the 10 states with the greatest increases in PrEP coverage, the EAPC decreased 4.0% (95% confidence interval [CI], -5.2% to -2.9%). On average, across the states and District of Columbia, EAPC for a given year decreased by 1.1% (95% CI, -1.77% to -.49%) for an increase in PrEP coverage of 1 per 100 persons with indications. When controlling for VS, the state-specific EAPC for a given year decreased by 1.3% (95% CI, -2.12% to -.57%) for an increase in PrEP coverage of 1 per 100 persons with indications. CONCLUSIONS: We found statistically significant associations between jurisdictional increases in PrEP coverage and decreases in EAPC independent of changes in VS, which supports bringing PrEP use to scale in the US to accelerate reductions in HIV infections.

Statistical methods used in the public health literature and implications for training of public health professionals.

Statistical literacy and knowledge is needed to read and understand the public health literature. The purpose of this study was to quantify basic and advanced statistical methods used in public health research. We randomly sampled 216 published articles from seven top tier general public health journals. Studies were reviewed by two readers and a standardized data collection form completed for each article. Data were analyzed with descriptive statistics and frequency distributions. Results were summarized for statistical methods used in the literature, including descriptive and inferential statistics, modeling, advanced statistical techniques, and statistical software used. Approximately 81.9% of articles reported an observational study design and 93.1% of articles were substantively focused. Descriptive statistics in table or graphical form were reported in more than 95% of the articles, and statistical inference reported in more than 76% of the studies reviewed. These results reveal the types of statistical methods currently used in the public health literature. Although this study did not obtain information on what should be taught, information on statistical methods being used is useful for curriculum development in graduate health sciences education, as well as making informed decisions about continuing education for public health professionals.

Repeat abortions in New York City, 2010.

This study aims to describe factors associated with the number of past abortions obtained by New York City (NYC) abortion patients in 2010. We calculated rates of first and repeat abortion by age, race/ethnicity, and neighborhood-level poverty and the mean number of self-reported past abortions by age, race/ethnicity, neighborhood-level poverty, number of living children, education, payment method, marital status, and nativity. We used negative binomial regression to predict number of past abortions by patient characteristics. Of the 76,614 abortions reported for NYC residents in 2010, 57% were repeat abortions. Repeat abortions comprised >50% of total abortions among the majority of sociodemographic groups we examined. Overall, mean number of past abortions was 1.3. Mean number of past abortions was higher for women aged 30-34 years (1.77), women with ≥5 children (2.50), and black non-Hispanic women (1.52). After multivariable regression, age, race/ethnicity, and number of children were the strongest predictors of number of past abortions. This analysis demonstrates that, although socioeconomic disparities exist, all abortion patients are at high risk for repeat unintended pregnancy and abortion.

Risk for Tuberculosis Disease Among Contacts with Prior Positive Tuberculin Skin Test: A retrospective Cohort Study, New York City.

BACKGROUND: Patients with prior positive tuberculin skin test (TST) results may benefit from prophylaxis after repeat exposure to infectious tuberculosis (TB). OBJECTIVE: To evaluate factors associated with active TB disease among persons with prior positive TST results named as contacts of persons with infectious TB. DESIGN: Population-based retrospective cohort study. PARTICIPANTS: A total of 2,933 contacts with prior positive TST results recently exposed to infectious TB identified in New York City's TB registry during the period from January 1, 1997 through December 31, 2003. MAIN MEASUREMENTS: Contacts developing active TB disease ≤ 4 years after exposure were identified and compared with those who did not, using Poisson regression analysis. Genotyping was performed on selected Mycobacterium tuberculosis-positive isolates. KEY RESULTS: Among contacts with prior positive TST results, 39 (1.3 %) developed active TB disease ≤ 4 years after exposure (≤ 2 years: 34). Risk factors for contacts that were independently associated with TB were age < 5 years (adjusted prevalence ratio [aPR] = 19.48; 95 % confidence interval [CI] = 7.15-53.09), household exposure (aPR = 2.60;CI = 1.30-5.21), exposure to infectious patients (i.e., cavities on chest radiograph, acid-fast bacilli on sputum smear; aPR = 1.9 3; CI = 1.01-3.71), and exposure to a U.S.-born index patient (aPR = 4.04; CI = 1.95-8.38). Receipt of more than 1 month of treatment for latent TB infection following the current contact investigation was found to be protective (aPR = 0.27; CI = .08-0.93). Genotype results were concordant with the index patients among 14 of 15 contacts who developed active TB disease and had genotyping results available. CONCLUSIONS: Concordant genotype results and a high proportion of contacts developing active TB disease within 2 years of exposure indicate that those with prior positive TST results likely developed active TB disease from recent rather than remote infection. Healthcare providers should consider prophylaxis for contacts with prior TB infection, especially young children and close contacts of TB patients (e.g., those with household exposure).

Previously undiagnosed HIV infections identified through cluster investigation, North Carolina, 2002-2007.

During cluster investigation, index patients name social contacts that are not sex or drug-sharing partners. The likelihood of identifying new HIV infections among social contacts is unknown. We hypothesized greater odds of identifying new infections among social contacts identified by men who report sex with men (MSM). We reviewed North Carolina HIV diagnoses during 2002-2005 and used logistic regression to compare testing results among social contacts of MSM, men who report sex with women only (MSW) and women. HIV was newly diagnosed among 54/601 (9.0 %) social contacts tested named by MSM, 16/522 (3.1 %) named by MSW, and 23/639 (3.6 %) named by women. Compared with those named by MSW, odds of new HIV diagnosis were greater among MSM social contacts (adjusted odds ratio: 2.5; 95 % confidence interval: 1.3-4.7). Testing social contacts identified previously undiagnosed HIV infections and could provide an opportunity to interrupt transmission.

Infection with Colorado tick fever virus among humans and ticks in a national park and forest, Wyoming, 2010.

BACKGROUND: Colorado tick fever (CTF) is an underreported tick-borne viral disease occurring in the western United States. CTF illness includes fever, headache, and severe myalgia lasting for weeks. Wyoming has one of the highest CTF incidence rates with approximately 30% of infected persons reporting tick exposure in a Wyoming National Park or Forest before symptom onset. We assessed CTF virus infections among humans and Dermacentor andersoni ticks in Grand Teton National Park (GRTE) and Bridger-Teton National Forest (BTNF). METHODS: In June of 2010, 526 eligible employees were approached to participate in a baseline and 3-month follow-up serosurvey and risk behavior survey. Seropositivity was defined as antibody titers against CTF virus ≥10, as measured by the plaque reduction neutralization test. Ticks were collected at 27 sites within GRTE/BTNF and tested by RT-PCR for the CTF virus. RESULTS: A total of 126 (24%) employees participated in the baseline and follow-up study visits. Three (2%) employees were seropositive for CTF virus infection at baseline. During the study, 47 (37%) participants found unattached ticks on themselves, and 12 (10%) found attached ticks; however, no participants seroconverted against CTF virus. Walking through sagebrush (p=0.04) and spending time at ≥7000 feet elevation (p<0.01) were significantly associated with tick exposure. Ninety-nine percent (174/176) of ticks were D. andersoni, and all were found at ≥7000 feet elevation in sagebrush areas; 37 (21%) ticks tested positive for CTF virus and were found at 10 (38%) of 26 sites sampled. CONCLUSIONS: Although no GRTE or BTNF employees were infected with CTF virus during the study period, high rates of infected ticks were identified in areas with sagebrush at ≥7000 feet. CTF education and personal protection measures against tick exposure should be targeted to visitors and employees traveling to the high-risk environs identified in this study.

Effect of vaccination coordinators on socioeconomic disparities in immunization among the 2006 Connecticut birth cohort.

OBJECTIVES: We examined socioeconomic status (SES) disparities and the influence of state Immunization Action Plan-funded vaccination coordinators located in low-SES areas of Connecticut on childhood vaccination up-to-date (UTD) status at age 24 months. METHODS: We examined predictors of underimmunization among the 2006 birth cohort (n = 34,568) in the state's Immunization Information System, including individual demographic and SES data, census tract SES data, and residence in an area with a vaccination coordinator. We conducted multilevel logistic regression analyses. RESULTS: Overall, 81% of children were UTD. Differences by race/ethnicity and census tract SES were typically under 5%. Not being UTD at age 7 months was the strongest predictor of underimmunization at age 24 months. Among children who were not UTD at age 7 months, only Medicaid enrollment (adjusted odds ratio [AOR] = 0.6; 95% confidence interval [CI] = 0.5, 0.7) and residence in an area with a vaccination coordinator (AOR = 0.7; 95% CI = 0.6, 0.9) significantly decreased the odds of subsequent underimmunization. CONCLUSIONS: SES disparities associated with underimmunization at age 24 months were limited. Efforts focused on vaccinating infants born in low SES circumstances can minimize disparities.