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Importance: Despite widespread vaccination against COVID-19 in the United States, there are limited empirical data quantifying their public health impact in the population., Objective: To estimate the number of COVID-19 cases, hospitalizations, and deaths directly averted because of COVID-19 vaccination in California., Design, Setting, and Participants: This modeling study used person-level data provided by the California Department of Public Health (CDPH) on COVID-19 cases, hospitalizations, and deaths as well as COVID-19 vaccine administration from January 1, 2020, to October 16, 2021. A statistical model was used to estimate the number of COVID-19 cases that would have occurred in the vaccine era (November 29, 2020, to October 16, 2021) in the absence of vaccination based on the ratio of the number of cases among the unvaccinated (aged <12 years) and vaccine-eligible groups (aged ≥12 years) before vaccine introduction. Vaccine-averted COVID-19 cases were estimated by finding the difference between the projected and observed number of COVID-19 cases. Averted COVID-19 hospitalizations and deaths were assessed by applying estimated hospitalization and case fatality risks to estimates of vaccine-averted COVID-19 cases. As a sensitivity analysis, a second independent model was developed to estimate the number of vaccine-averted COVID-19 outcomes by applying published data on vaccine effectiveness to data on COVID-19 vaccine administration and estimated risk of COVID-19 over time., Exposure: COVID-19 vaccination., Main Outcomes and Measures: Number of COVID-19 cases, hospitalizations, and deaths estimated to have been averted because of COVID-19 vaccination., Results: There were 4 585 248 confirmed COVID-19 cases, 240 718 hospitalizations, and 70 406 deaths in California from January 1, 2020, to October 16, 2021, during which 27 164 680 vaccine-eligible individuals aged 12 years and older were reported to have received at least 1 dose of a COVID-19 vaccine in the vaccine era (79.5% of the eligible population). The primary model estimated that COVID-19 vaccination averted 1 523 500 (95% prediction interval [PI], 976 800-2 230 800) COVID-19 cases in California, corresponding to a 72% (95% PI, 53%-91%) relative reduction in cases because of vaccination. COVID-19 vaccination was estimated to have averted 72 930 (95% PI, 53 250-99 160) hospitalizations and 19 430 (95% PI, 14 840-26 230) deaths during the study period. The alternative model identified comparable findings., Conclusions and Relevance: This study provides evidence of the public health benefit of COVID-19 vaccination in the United States and further supports the urgency for continued vaccination.

A key public health question during any disease outbreak when limited vaccine is available is who should be prioritized for early vaccination. Most vaccine prioritization analyses only consider variation in risk of infection and death by a single risk factor, such as age. We provide a more granular approach with stratification by demographics, risk factors, and location. We use this approach to compare the impact of different COVID-19 vaccine prioritization strategies on COVID-19 cases, deaths and disability-adjusted life years (DALYs) over the first 6 months of vaccine rollout, using California as a case example. We estimate the proportion of cases, deaths and DALYs averted relative to no vaccination for strategies prioritizing vaccination by a single risk factor and by multiple risk factors (e.g. age, location). When targeting by a single risk factor, we find that age-based targeting averts the most deaths (62% for 5 million individuals vaccinated) and DALYs (38%) and targeting essential workers averts the least deaths (31%) and DALYs (24%) over the first 6 months of rollout. However, targeting by two or more risk factors simultaneously averts up to 40% more DALYs. Our findings highlight the potential value of multiple-risk-factor targeting of vaccination against COVID-19 and other infectious diseases, but must be balanced with feasibility for policy., (© 2022. The Author(s).)

Background: Epidemics of COVID-19 in student populations at universities were a key concern for the 2020-2021 school year. The University of California (UC) System developed a set of recommendations to reduce campus infection rates. SARS-CoV-2 test results are summarized for the ten UC campuses during the Fall 2020 term., Methods: UC mitigation efforts included protocols for the arrival of students living on-campus students, non-pharmaceutical interventions, daily symptom monitoring, symptomatic testing, asymptomatic surveillance testing, isolation and quarantine protocols, student ambassador programs for health education, campus health and safety pledges, and lowered density of on-campus student housing. We used data from UC campuses, the UC Health-California Department of Public Health Data Modeling Consortium, and the U.S. Census to estimate the proportion of each campus' student populations that tested positive for SARS-CoV-2 and compared it to the fraction individuals aged 20-29 years who tested positive in their respective counties., Results: SARS-CoV-2 cases in campus populations were generally low in September and October 2020, but increased in November and especially December, and were highest in early to mid-January 2021, mirroring case trajectories in their respective counties. Many students were infected during the Thanksgiving and winter holiday recesses and were detected as cases upon returning to campus. The proportion of students who tested positive for SARS-CoV-2 during Fall 2020 ranged from 1.2% to 5.2% for students living on campus and was similar to students living off campus. For most UC campuses the proportion of students testing positive was lower than that for the 20-29-year-old population in which campuses were located., Conclusions: The layered mitigation approach used on UC campuses, informed by public health science and augmented perhaps by a more compliant population, likely minimized campus transmission and outbreaks and limited transmission to surrounding communities. University policies that include these mitigation efforts in Fall 2020 along with SARS-CoV-2 vaccination, may alleviate some local concerns about college students returning to communities and facilitate resumption of normal campus operations and in-person instruction., Competing Interests: No authors have competing interests

Background: Accurate gestational dating is a critical component of obstetric and newborn care. In the absence of early ultrasound, many clinicians rely on less accurate measures, such as last menstrual period or symphysis-fundal height during pregnancy, or Dubowitz scoring or the Ballard (or New Ballard) method at birth. These measures often underestimate or overestimate gestational age and can lead to misclassification of babies as born preterm, which has both short- and long-term clinical care and public health implications., Objective: We sought to evaluate whether metabolic markers in newborns measured as part of routine screening for treatable inborn errors of metabolism can be used to develop a population-level metabolic gestational dating algorithm that is robust despite intrauterine growth restriction and can be used when fetal ultrasound dating is not available. We focused specifically on the ability of these markers to differentiate preterm births (PTBs) (<37 weeks) from term births and to assign a specific gestational age in the PTB group., Study Design: We evaluated a cohort of 729,503 singleton newborns with a California birth in 2005 through 2011 who had routine newborn metabolic screening and fetal ultrasound dating at 11-20 weeks' gestation. Using training and testing subsets (divided in a ratio of 3:1) we evaluated the association among PTB, target newborn characteristics, acylcarnitines, amino acids, thyroid-stimulating hormone, 17-hydroxyprogesterone, and galactose-1-phosphate-uridyl-transferase. We used multivariate backward stepwise regression to test for associations and linear discriminate analyses to create a linear function for PTB and to assign a specific week of gestation. We used sensitivity, specificity, and positive predictive value to evaluate the performance of linear functions., Results: Along with birthweight and infant age at test, we included 35 of the 51 metabolic markers measured in the final multivariate model comparing PTBs and term births. Using a linear discriminate analyses-derived linear function, we were able to sort PTBs and term births accurately with sensitivities and specificities of ≥95% in both the training and testing subsets. Assignment of a specific week of gestation in those identified as PTBs resulted in the correct assignment of week ±2 weeks in 89.8% of all newborns in the training and 91.7% of those in the testing subset. When PTB rates were modeled using the metabolic dating algorithm compared to fetal ultrasound, PTB rates were 7.15% vs 6.11% in the training subset and 7.31% vs 6.25% in the testing subset., Conclusion: When considered in combination with birthweight and hours of age at test, metabolic profile evaluated within 8 days of birth appears to be a useful measure of PTB and, among those born preterm, of specific week of gestation ±2 weeks. Dating by metabolic profile may be useful in instances where there is no fetal ultrasound due to lack of availability or late entry into care., (Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.)

The numbers of reported cases of coccidioidomycosis in Arizona and California have risen dramatically over the past decade, with a 97.8% and 91.1% increase in incidence rates from 2001 to 2006 in the two states, respectively. Of those cases with reported race/ethnicity information, Black/African Americans in Arizona and Hispanics and African/Americans in California experienced a disproportionately higher frequency of disease compared to other racial/ethnic groups. Lack of early diagnosis continues to be a problem, particularly in suspect community-acquired pneumonia, underscoring the need for more rapid and sensitive tests. Similarly, the inability of currently available therapeutics to reduce the duration and morbidity of this disease underscores the need for improved therapeutics and a preventive vaccine.

Although the epidemiology of coccidioidomycosis has been well described, there is a paucity of recent data on the public health burden associated with this disease. Accordingly, California's Inpatient Hospital Discharge Data Set from 1997 to 2002 was used to calculate the incidence of hospitalization for coccidioidomycosis by county, year, age, race, ethnicity, and gender. The overall finding that coccidioidomycosis has a significant impact in endemic areas supports the conclusion that the need for a preventive vaccine is great. Investigators of the Valley Fever Vaccine Project (VFVP) have successfully identified a number of recombinant coccidioidal protein antigens and two attenuated mutant strains that have been evaluated as vaccines, demonstrating protective responses in murine models. Efforts to select and develop a vaccine for human clinical trials are in progress.

We used hospital discharge data to estimate incidence and distribution of coccidioidomycosis-associated hospitalizations in California. For 1997-2002, the average annual rate of hospitalization was 3.67 per 100,000 population. County of residence, older age, black race, male sex, HIV infection, and pregnancy were strongly associated with increased risk for hospitalization.

Perchlorate (ClO4-) has been detected in groundwater sources in numerous communities in California and other parts of the United States, raising concerns about potential impacts on health. For California communities where ClO4- was tested in 1997 and 1998, we evaluated the prevalence of primary congenital hypothyroidism (PCH) and high thyroid-stimulating hormone (TSH) levels among the 342,257 California newborns screened in 1998. We compared thyroid function results among newborns from 24 communities with average ClO4- concentrations in drinking water>5 microg/L (n=50,326) to newborns from 287 communities with average concentrations5 microg/L were observed, with 20.4 expected [adjusted prevalence odds ratio (POR)=0.71; 95% confidence interval (CI), 0.40-1.19]. Although only 36% of all California newborns were screened before 24 hr of age in 1998, nearly 80% of newborns with high TSH were screened before 24 hr of age. Because of the physiologic postnatal surge of TSH, the results for newborns screened before 24 hr were uninformative for assessing an environmental impact. For newborns screened>or=24 hr, the adjusted POR for high TSH was 0.73 (95% CI, 0.40-1.23). All adjusted odds ratios (ORs) were controlled for sex, ethnicity, birth weight, and multiple birth status. Using an assessment of ClO4- in drinking water based on available data, we did not observe an association between estimated average ClO4- concentrations>5 microg/L in drinking water supplies and the prevalence of clinically diagnosed PCH or high TSH concentrations.

To meet federal recommendations to collect case reports of HIV infection, California has adopted a non-name code system to conduct HIV surveillance. The objective of this study was to evaluate among HIV test takers the acceptability and preferences for the 3 major types of HIV infection reporting-name, name-to-code, and non-name code. Interviewer-administered exit surveys with spoken scripts and matching printed materials clearly outlining the 3 HIV reporting options were conducted among HIV test takers immediately following appointments for pretest HIV counseling and blood collection. The study enrolled 208 HIV test takers at 14 publicly funded HIV testing sites in 4 California counties (Los Angeles, Riverside, Fresno, and Santa Clara). Overall with respect to which would be the most acceptable system, 67% reported non-name code, 19% reported name-to-code, and 12% reported name-based HIV reporting (P < 0.0001). A second sample of 226 exit surveys taken 1 year following implementation of California's non-name code HIV infection reporting system continued to show a significant preference for non-name code HIV infection reporting. Significant independent predictors of a preference for coded HIV reporting in both the pre- and postimplementation period were men who have sex with men (odds ratio [OR] = 5.7, 95% CI: 1.2-26 in the preperiod) and having just taken an anonymous HIV test (OR = 3.6, 95% CI: 1.4-9.3, P = 0.009 preperiod). Were the state to adopt name-based HIV reporting, significantly fewer individuals report being likely in the next 12 months to have a confidential HIV test than report being likely to have an anonymous HIV test (51% likely confidential vs. 76% likely anonymous, P < 0.0001). This analysis documents strong support, among HIV test takers in California, for a non-name coded HIV reporting system and indicates a high probability of a shift away from confidential testing toward anonymous testing under a scenario of name-based reporting. This shift is of concern as confidential HIV testing is the basis of US HIV surveillance systems.

The objectives of this study were to evaluate whether there were higher rates of primary congenital hypothyroidism (PCH) or elevated concentrations of thyroid-stimulating hormone (TSH) in a community where perchlorate was detected in groundwater wells. The adjusted PCH prevalence ratio and 95% confidence interval (CI) comparing the study community to San Bernardino and Riverside counties combined was 0.45 (95% CI=0.06-1.64). The odds ratios for elevated TSH concentration were 1.24 (95% CI=0.89-1.68) among all newborns screened and 0.69 (95% CI=0.27-1.45) for newborns whose age at screening was 18 hours or greater. Age of the newborn at time of screening was the most important predictor of the TSH level. These findings suggest that residence in a community with potential perchlorate exposure has not impacted PCH rates or newborn thyroid function.

To estimate the prevalence and predictors of hepatitis C virus (HCV) infection among inmates, a cross-sectional survey was conducted in 1994 among inmates entering six reception centers of the California Department of Corrections. Discarded serum samples were tested for antibodies to human immunodeficiency virus (HIV), HCV, hepatitis B core, and hepatitis B surface antigen (HBsAg). Of 4,513 inmates in this study, 87.0% were men and 13.0% were women. Among male inmates, 39.4% were anti-HCV-positive; by race/ethnicity, prevalences were highest among whites (49.1%). Among female inmates, 53.5% were anti-HCV-positive; the prevalence was highest among Latinas (69.7%). In addition, rates for HIV were 2.5% for men and 3.1% for women; and for HBsAg, 2.2% (men) and 1.2% (women). These data indicate that HCV infection is common among both men and women entering prison. The high seroprevalence of anti-HCV-positive inmates may reflect an increased prevalence of high-risk behaviors and should be of concern to the communities to which these inmates will be released.

Background: Several changes can be anticipated in the practice of communicable disease control as a result of the health care delivery system's transition from a predominantly fee-for-service system to a predominantly managed care system. These changes will clearly involve clinical services provided by public health agencies, such as immunizations and diagnosis and treatment of tuberculosis and sexually transmitted diseases, as well as those that do not involve direct patient care, such as public health surveillance, disease investigation, outbreak control, contact tracing, public health laboratory services, and health education., Methods: In this paper I review the potential impact of managed care on each of these areas of communicable disease control and suggest strategies for minimizing adverse effects and maximizing potential areas of cooperation., Results: Examples of successful strategies include California's Medi-Cal managed care expansion, which allows local public health agencies to bill managed care organizations for the sexually transmitted disease, immunization, and confidential HIV services they provide to managed care beneficiaries. A different strategy is illustrated by the Pacific Business Group on Health, an employer-based purchasing group, that uses purchasing power to standardize the clinical preventive services benefit across all plans with which it contracts and to promote immunization goals., Conclusion: This analysis and these examples suggest that the emergence of managed care as the predominant form of health care financing and delivery in the United States offers an important opportunity for public health.

Objectives: An investigation was conducted to determine whether ongoing transmission of Mycobacterium tuberculosis was occurring in a California state prison., Method: Prison pharmacy records were used to identify cases of active tuberculosis (TB)., Results: Ten of the 18 cases of active TB treated at the facility during 1991 were diagnosed at the prison that same year (an incidence of 184 per 100,000). Three inmates were infectious for a total of 7 months while imprisoned. The prevalence of TB skin test-positivity among inmates was 30%, and the incidence of new infection attributable to incarceration was 5.9 per 100 inmates per year., Conclusions: Transmission of M. tuberculosis may be occurring in the California prison system.

Unlabelled: The objective was to determine if a cluster of chronic fatigue syndrome (CFS)-like illness had occurred among employees in two large state office buildings in northern California, and to identify risk factors for and features of fatiguing illness in this population., Design: case-control study., Population and Setting: Over 3300 current employees in two state office buildings and employees in a comparable "control" building. Information was collected on demographic and occupational variables, the occurrence of fatiguing illness for at least one month in the previous year, and the presence of 36 symptoms. A total of 3312 (82%) of 4035 employees returned questionnaires. Overall, 618 (18.7%) persons reported fatigue lasting at least one month; including 382 (11.5%) with fatigue of at least six months' duration and 75 (2.3%) with symptoms compatible with a CFS-like illness. Independent risk factors for fatigue lasting one month or longer were found to be Native American ethnicity (OR 2.4, CI 1.1,5.3), Hispanic ethnicity (OR 1.7, CI 1.3,2.3), female sex (OR 1.5, CI 1.2,1.9), gross household incomes of less than $50,000 (OR 1.3, CI 1.1,1.6), and less than a college education (OR 1.3, CI 1.1,1.6). Similar risks were observed for persons who reported fatigue lasting six months or longer. Female sex (OR 3.2, CI 1.7, 6.4) was the only independent risk factor found for those persons classified as having a CFS-like illness. Case prevalence rates for all three categories of fatigue, as determined by multivariate analysis, were not significantly different among buildings. Despite finding a substantial number of employees with fatiguing illness in the two state office buildings, the prevalence was not significantly different than that for a comparable control building. Previously unidentified risk factors for fatigue of at least one month and at least six months identified in this population included Hispanic ethnicity, not having completed college, and income below $50,000.

On January 1, 1993, the case definition of the acquired immunodeficiency syndrome (AIDS) in adults and adolescents used for monitoring the AIDS epidemic in California was expanded to include persons infected with the human immunodeficiency virus (HIV) with CD4 T-lymphocyte counts of less than 200 x 10(6) per liter (< 200 per mm3), pulmonary tuberculosis, recurrent pneumonia, or invasive cervical cancer. To assess the implications of this revision on AIDS case reporting in California, we compared cases reported through the end of 1994 based on 1 or more of the 4 new AIDS-defining conditions added in 1993 to cases reported based on pre-1993 AIDS-defining opportunistic infections and cancers. The 4 new conditions included in the 1993 expanded AIDS case definition accounted for a 23% increase in cumulative AIDS cases reported in California by the end of 1993, a 170% increase in the number of cases reported during 1993, and an 88% increase in the number of patients with AIDS living at the end of 1993. The number of cases reported in 1993 (19,629) was 124% more than that reported in 1992 (8,780) and 69% more than that reported in 1994 (11,587). The proportion of cases among women, injection-drug users, and African Americans also increased as a result of this change in the case definition. The expansion of the case definition may have resulted in a peak or plateau in the AIDS incidence in California because of reporting earlier in the HIV disease progression. The expanded case definition has enhanced the usefulness of AIDS surveillance data for targeting secondary prevention efforts, but more behavioral and HIV serosurveys are still needed to adequately target primary HIV prevention efforts.

To determine the proportion and distribution of drug-resistant Mycobacterium tuberculosis in California, we surveyed all California counties for drug-susceptibility test results for initial isolates from tuberculosis cases counted during the first quarters of 1991 and 1992. Overall, drug-susceptibility test results were not available for 17% of isolates. Among isolates with available test results, the proportion with resistance to isoniazid averaged 8.7%, and the proportion with resistance to at least 2 drugs, multidrug resistance, averaged 5.9% during these two quarters. The proportion of isolates with drug resistance did not change substantially during these time periods. The proportion with combined isoniazid and rifampin resistance remained stable at about 1.1%. Among persons whose isolates were tested for drug resistance, those with a known previous diagnosis of tuberculosis (relative risk [RR] = 2.6; 95% confidence interval [CI], 1.6 to 4.3; P < .01) and persons who were foreign born (RR = 1.7; 95% CI, 1.1 to 2.7; P = .014) were more likely to have isoniazid-resistant organisms. These statewide data suggest that the initial tuberculosis treatment regimen in California should include 4 antituberculosis drugs, as recommended by the American Thoracic Society and the Centers for Disease Control and Prevention for areas with a prevalence of isoniazid resistance of 4% or greater. The lack of test results for 1 in 6 patients with tuberculosis suggests the need for improved physician and laboratorian education to implement the recommendations that drug susceptibility be tested on all initial isolates.

To determine the incidence of physician-diagnosed Lyme disease in an endemic area of California, an active surveillance program was implemented in Lake, Mendocino, Sonoma, and southern Humboldt counties. More than 200 medical care providers were called monthly for their list of suspected cases of Lyme disease. Pertinent information was abstracted from the medical record of each patient. Of 153 cases of possible early Lyme disease ascertained from July 1991 to December 1992, 37% consisted of physician-diagnosed erythema migrans. Only 58% of erythema migrans rashes were at least 5 cm in diameter. An additional 43 patients had suspicious rashes not classified as erythema migrans. Of 166 patients with possible late-stage Lyme disease, 31% had specific clinical symptoms and 75% had a positive serologic test. With an incident case defined as physician-diagnosed erythema migrans of at least 5 cm in diameter, the annual incidence of Lyme disease in northwestern coastal California according to active surveillance only was 5.5 per 100,000. The rate of Lyme disease in California is substantially lower than that in the Atlantic northeastern United States. Many suspected cases of Lyme disease in this endemic area do not meet surveillance criteria, which are intentionally restrictive. Although some of the illnesses not meeting surveillance criteria may be due to infection with Borrelia burgdorferi, it appears that Lyme disease is being overdiagnosed in this area.

During 1988 through 1990, California experienced its worst measles epidemic in more than a decade, with 16,400 reported cases, 3,390 hospital admissions, and 75 deaths. More than half of the patients were younger than 5 years; the highest incidence was among infants younger than 12 months. The epidemic centered in low-income Hispanic communities in southern and central California. The major cause of the epidemic was low immunization levels among preschool-aged children and young adults. Rates of complications, admission to hospital, and death were surprisingly high. Outbreak control efforts met with indeterminate success. Problems with these efforts included insufficient funding early in the epidemic and disappointing public response to community-based immunization campaigns. The cost of medical care and outbreak control for the epidemic is conservatively estimated at $30.9 million. Unless the level of immunization in preschool-aged children is increased, this type of epidemic will probably recur.

Cysticercosis, a sometimes fatal ailment caused by larvae of the pork tapeworm Taenia solium, became a reportable disease in California in 1989. During the first year, from 1 April 1989 through 31 March 1990, 134 cases were reported to the California Department of Health Services. All of the 112 patients for whom laboratory diagnostic test data were obtained had neurocysticercosis. Nearly all (117) of the 127 patients whose race and ethnic background were known had a Hispanic background, and most of the 112 patients whose country of birth or prior residence was known had immigrated from T. solium-endemic countries. However, three of 11 patients born in the United States said they had never traveled outside the country, and it appears possible that indigenous transmission has been occurring. These findings affirm that neurocysticercosis should be included in the differential diagnosis of neurologic symptoms in patients who have immigrated from or traveled to T. solium-endemic countries, and also in those who have been in close contact with immigrants from endemic countries.

Tuberculosis has been reported previously in patients with acquired immunodeficiency syndrome who are at increased risk of prior infection with Mycobacterium tuberculosis. We performed a population-based study of AIDS and tuberculosis in San Francisco using the Tuberculosis and AIDS Registries of the San Francisco Department of Public Health. Of 287 cases of tuberculosis in non-Asian-born males 15 to 60 yr of age reported from 1981 through 1985, 35 (12%) also had AIDS, including 23 American-born whites. Patients with tuberculosis and AIDS were more likely to be nonwhite and heterosexual intravenous drug users than were AIDS patients without tuberculosis. Fifty-one percent had tuberculosis diagnosed before AIDS, and 37 percent had AIDS diagnosed at least 1 month prior to the diagnosis of tuberculosis. Although the lungs were the most frequent site of tuberculosis in both AIDS and non-AIDS patients, 60% of the AIDS group had at least 1 extrapulmonary site of disease compared to 28% of the non-AIDS group (p less than 0.001). Nonsignificant tuberculin skin tests were more common in AIDS patients (14 of 23 patients tested) than in non-AIDS patients (12 of 129 patients tested; p less than 0.0001). Chest radiographs in AIDS patients showed predominantly diffuse or miliary infiltrates (60%), whereas non-AIDS patients had predominantly focal infiltrates and/or cavitation (68%). Response to antituberculosis therapy was favorable in AIDS patients, although adverse drug reactions occurred more frequently than in non-AIDS patients (p less than 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)