Epidemiology of Chronic Hepatitis B Virus Infection, Alameda County, California, 2017-2021.

CONTEXT: In the United States, chronic hepatitis B (CHB) virus infection predominantly affects ethnic minorities and vulnerable populations. OBJECTIVE: We analyzed surveillance data to describe CHB epidemiology to guide hepatitis B virus (HBV) elimination efforts in Alameda County. DESIGN: Persons with CHB during 2017-2021 were identified by ≥2 positive HBV tests (ie, HBsAg, HbeAg, and HBV DNA) ≥180 days apart using data from California Reportable Disease Information Exchange. Persons with CHB were stratified by age, race/ethnicity, zip code-based Healthy Places Index (HPI), and federally designated Medically Underserved Areas (MUA). Comparisons of reported CHB prevalence between groups utilized z test; comparisons between MUA regions utilized chi-square testing. RESULTS: A total of 8122 persons with CHB were identified; reported 5-year CHB prevalence was 0.53% (95% confidence interval: 0.52%-0.54%). Reported CHB 5-year prevalence was significantly higher among persons aged 50 to 69 years old than persons aged 30 to 49 years old (0.99%, 0.78%; P < .001) and Asians, Native Hawaiian/Pacific Islanders, African Americans compared to Whites (1.22%, 0.56%, 0.18%, 0.06%; P < .001). Reported CHB 5-year prevalence in the 2 lowest and most disadvantaged HPI quartiles was significantly higher than the 2 highest quartiles (0.55%, 0.68%, 0.37%, 0.42%; P < .001). The 1918 persons with CHB in MUA, compared to 5859 non-MUA persons, were significantly more likely to be African American (7%, 3%; P < .001) and from the lowest HPI quartile (79%, 19%; P < .001). CONCLUSIONS: Reported CHB 5-year prevalence in Alameda County was 1.5 times the national prevalence estimates, and reported prevalence was highest among Asians and persons in more disadvantaged areas. Analysis of local CHB surveillance data can guide public health efforts toward HBV elimination.

Epidemiology of Mpox Cases, and Tecovirimat and JYNNEOS Utilization, Alameda County, California, June-October 2022.

CONTEXT: The 2022 United States mpox outbreak disproportionately affected racial and ethnic minority gay, bisexual, and other men who have sex with men. PROGRAM: We utilized surveillance data and vaccination registries to determine whether populations most impacted by mpox in Alameda County received JYNNEOS vaccines and tecovirimat (TPOXX) during June 1-October 31, 2022. IMPLEMENTATION: Alameda County Public Health Department responded to the mpox epidemic through partnerships with local health care providers who serve communities disproportionately affected by mpox. EVALUATION: During June 1-October 31, 2022, a total of 242 mpox cases were identified in Alameda County. Mpox incidence rates per 100 000 were highest among Black/African American (35.7; 95% confidence interval [CI], 26.8-46.5) and Hispanic/Latinx (25.1; CI, 20.1-30.9) residents, compared to Asian (3.8; CI, 2.3-5.9) and White (10.5; CI, 7.7-13.9) residents. Most confirmed cases were identified as gay, lesbian, or same-gender-loving (134, 67.3%) and bisexual (31, 15.6%); 226 (93.8%) cases were male. Sixty-nine (28.5%) mpox patients received TPOXX. There were no statistically significant differences in demographic and clinical characteristics of mpox cases when compared by TPOXX receipt status. JYNNEOS vaccine was received by 8277 Alameda County residents. The largest proportion of vaccinees were White residents (40.2%). Administration rates per 100 000 men who have sex with men were lowest among Asian and Hispanic/Latinx individuals, at 8779 (CI, 8283-9296) and 14 953 (CI, 14 156-15 784), respectively. Black/African American and Hispanic/Latinx males had the lowest vaccination-to-case ratios at 16.7 and 14.8, respectively. DISCUSSION: Mpox disproportionately affected Black/African American and Hispanic/Latinx men who have sex with men in Alameda County. Strong partnerships with local health care providers ensured that persons with mpox received TPOXX treatment when indicated. However, higher JYNNEOS vaccine uptake in Black and Latinx communities needs improvement through ongoing and meaningful engagement with Black/African American and Hispanic/Latinx gay, bisexual, and transgender communities.

Epidemiology of Culture-Negative Pulmonary Tuberculosis-Alameda County, 2010-2019.

CONTEXT: Patients with culture-negative pulmonary TB (PTB) can face delays in diagnosis that worsen outcomes and lead to ongoing transmission. An understanding of current trends and characteristics of culture-negative PTB can support earlier detection and access to care. OBJECTIVE: Describe epidemiology of culture-negative PTB. DESIGN, SETTING, PARTICIPANTS: We utilized Alameda County TB surveillance data from 2010 to 2019. Culture-negative PTB cases met clinical but not laboratory criteria for PTB per US National Tuberculosis Surveillance System definitions. We calculated trends in annual incidence and proportion of culture-negative PTB using Poisson and weighted linear regression, respectively. We further compared demographic and clinical characteristics among culture-negative versus culture-positive PTB cases. RESULTS: During 2010-2019, there were 870 cases of PTB, of which 152 (17%) were culture-negative. The incidence of culture-negative PTB declined by 76%, from 1.9/100 000 to 0.46/100 000 ( P for trend <.01), while the incidence of culture-positive PTB reduced by 37% (6.5/100 000 to 4.1/100 000, P for trend =.1). Culture-negative PTB case-patients were more likely than culture-positive PTB case-patients to be younger (7.9% were children <15 years old vs 1.1%; P < .01), recent immigrants within 5 years of arrival (38.2% vs 25.5%; P < .01), and have a TB contact (11.2% vs 2.9%; P < .01). Culture-negative PTB case-patients were less likely than culture-positive PTB case-patients to be evaluated because of TB symptoms (57.2% vs 74.7%; P < .01) or have cavitation on chest imaging (13.1% vs 38.8%; P < .01). At the same time culture-negative PTB case-patients were less likely to die during TB treatment (2.0% vs 9.6%; P < .01). CONCLUSIONS: The incidence of culture-negative PTB disproportionately declined compared with culture-positive TB and raises concern for gaps in detection. Expansion of screening programs for recent immigrants and TB contacts and greater recognition of risk factors may increase detection of culture-negative PTB.

Epidemiology of Coronavirus Disease 2019 at a County Jail-Alameda County, California, March 2020-March 2021.

CONTEXT: Coronavirus disease 2019 (COVID-19) incidence rates are 2- to 5-fold higher among persons incarcerated in the United States than in the general population. PROGRAM OR POLICY: We describe an outbreak investigation of COVID-19 at a jail (jail A) in Alameda County during March 2020-March 2021. IMPLEMENTATION: To prevent COVID-19 cases among incarcerated persons and employees, staff at jail A and the county public health department worked to develop and recommend infection control measures implemented by jail A including, but not limited to, face covering use among incarcerated persons and staff; cohorting incarcerated persons at a higher risk of severe COVID-19 in dedicated housing units; quarantining all newly detained individuals for 14 days; and offering testing for all symptomatic incarcerated persons, newly incarcerated persons at day 2 and day 10, and all persons who resided in a housing unit where a COVID-19 case was detected. EVALUATION: A total of 571 COVID-19 cases were detected among incarcerated persons at jail A during March 2020-March 2021, which represented a total incidence of 280 per 1000 population, 5 times higher than the rate in Alameda County. Of the 571 cases among incarcerated persons, 557 (98%) were male; 415 (73%) were aged 18 to 40 years; 249 (44%) were Latino; and 180 (32%) were African American; 354 (62%) were not symptomatic; and 220 (39%) had no comorbidities. Less than 2% of infected incarcerated persons were hospitalized, and no deaths were reported. DISCUSSION: COVID-19 disproportionately impacted persons incarcerated at jail A, with higher numbers among Latinos and African Americans. Implementation of COVID-19 infection control and testing measures, and collaboration between public health, law enforcement, and health care providers may have, in part, led to reductions in morbidity and mortality associated with COVID-19 at jail A.

Critical Role of the Human T-Cell Leukemia Virus Type 1 Capsid N-Terminal Domain for Gag-Gag Interactions and Virus Particle Assembly.

The retroviral Gag protein is the main structural protein responsible for virus particle assembly and release. Like human immunodeficiency virus type 1 (HIV-1) Gag, human T-cell leukemia virus type 1 (HTLV-1) has a structurally conserved capsid (CA) domain, including a ß-hairpin turn and a centralized coiled-coil-like structure of six α helices in the CA amino-terminal domain (NTD), as well as four α-helices in the CA carboxy-terminal domain (CTD). CA drives Gag oligomerization, which is critical for both immature Gag lattice formation and particle production. The HIV-1 CA CTD has previously been shown to be a primary determinant for CA-CA interactions, and while both the HTLV-1 CA NTD and CTD have been implicated in Gag-Gag interactions, our recent observations have implicated the HTLV-1 CA NTD as encoding key determinants that dictate particle morphology. Here, we have conducted alanine-scanning mutagenesis in the HTLV-1 CA NTD nucleotide-encoding sequences spanning the loop regions and amino acids at the beginning and ends of α-helices due to their structural dissimilarity from the HIV-1 CA NTD structure. We analyzed both Gag subcellular distribution and efficiency of particle production for these mutants. We discovered several important residues (i.e., M17, Q47/F48, and Y61). Modeling implicated that these residues reside at the dimer interface (i.e., M17 and Y61) or at the trimer interface (i.e., Q47/F48). Taken together, these observations highlight the critical role of the HTLV-1 CA NTD in Gag-Gag interactions and particle assembly, which is, to the best of our knowledge, in contrast to HIV-1 and other retroviruses.IMPORTANCE Retrovirus particle assembly and release from infected cells is driven by the Gag structural protein. Gag-Gag interactions, which form an oligomeric lattice structure at a particle budding site, are essential to the biogenesis of an infectious virus particle. The CA domain of Gag is generally thought to possess the key determinants for Gag-Gag interactions, and the present study has discovered several critical amino acid residues in the CA domain of HTLV-1 Gag, an important cancer-causing human retrovirus, which are distinct from that of HIV-1 as well as other retroviruses studied to date. Altogether, our results provide important new insights into a poorly understood aspect of HTLV-1 replication that significantly enhances our understanding of the molecular nature of Gag-Gag interaction determinants crucial for virus particle assembly.

Advanced pulmonary tuberculosis in Alameda County: Ten-year incidence and risk factors.

Background: Advanced pulmonary tuberculosis (APT) may reflect delays in tuberculosis (TB) diagnosis and contribute to ongoing disease transmission and poor outcomes. We characterized trends and factors associated with APT over ten years in a high TB-burden county within the United States. Methods: We evaluated microbiologically and clinically confirmed TB cases reported to the Alameda County Public Health Department during 2010-2019. APT was defined as the presence of cavitation on chest imaging and positive acid-fast bacilli sputum smear. Over the ten-year period, we determined overall incidence and annual trends, and conducted multivariable logistic regression to identify sociodemographic and clinical factors associated with APT. Results: We included 997 cases with pulmonary TB, of which 128 (12.8 %) had APT. The 10-year incidence of APT was 8.8 cases per 100,000, with no significant change in proportion over time. The median age of cases with APT were 50 years (IQR 32-61), 68 % were male, and 78.9 % were non-US-born. On multivariable assessment, APT cases were more likely than non-APT cases to use drugs in the past year (aOR 2.43, 95 % CI 1.10-35.09), to have diabetes (aOR 2.51, 95 % CI: 1.59-3.96), and be HIV negative (aOR 9.32 versus HIV positive, 95 % CI 1.87-169.77). While US nativity was not significantly associated with APT, it was an effect modifier. In stratified analysis, APT was more likely among those with drug-use in the last year among US-born, while diabetes was associated with APT among non-US-born individuals. Conclusions: APT remains a substantial proportion of TB cases. Efforts to increase awareness and access to care are needed for key risk groups including those with recent drug use or diabetes, with consideration of cultural and linguistic factors given differences by US nativity.

Epidemiology of carbapenem-resistant organisms in Alameda County, California, 2019-2021.

Objective: Carbapenem-resistant organisms (CROs) are an urgent health threat. Since 2017, Alameda County Health Public Health Department (ACPHD) mandates reporting of carbapenem-resistant Enterobacterales (CRE) and encourages voluntary reporting of non-CRE CROs including carbapenem-resistant Acinetobacter baumannii (CRAB) and carbapenem-resistant Pseudomonas aeruginosa (CRPA). Surveillance data from ACPHD were analyzed to describe the epidemiology of CROs and target public health interventions. Methods: Healthcare facilities in Alameda County reported CRO cases and submitted isolates to ACPHD to characterize carbapenemase genes; deaths were identified via the California Electronic Death Registration System. CRO cases with isolates resistant to one or more carbapenems were analyzed from surveillance data from July 2019 to June 2021. Results: Four hundred and forty-two cases of CROs were reported to Alameda County from 408 patients. The county case rate for CROs was 29 cases per 100,000 population, and cases significantly increased over the 2-year period. CRPA was most commonly reported (157 cases, 36%), and cases of CRAB increased 1.83-fold. One-hundred eighty-six (42%) cases were identified among residents of long-term care facilities; 152 (37%) patients had died by January 2022. One hundred and seven (24%) cases produced carbapenemases. Conclusions: The high burden of CROs in Alameda County highlights the need for continued partnership on reporting, testing, and infection prevention to limit the spread of resistant organisms. A large proportion of cases were identified in vulnerable long-term care residents, and CRAB was an emerging CRO among this population. Screening for CROs and surveillance at the local level are important to understand epidemiology and implement public health interventions.

Risk factors for third-generation cephalosporin-resistant and extended-spectrum ß-lactamase-producing Escherichia coli carriage in domestic animals of semirural parishes east of Quito, Ecuador.

Extended-spectrum ß-lactamase (ESBL)-producing and other antimicrobial resistant (AR) Escherichia coli threaten human and animal health worldwide. This study examined risk factors for domestic animal colonization with ceftriaxone-resistant (CR) and ESBL-producing E. coli in semirural parishes east of Quito, Ecuador, where small-scale food animal production is common. Survey data regarding household characteristics, animal care, and antimicrobial use were collected from 304 households over three sampling cycles, and 1195 environmental animal fecal samples were assessed for E. coli presence and antimicrobial susceptibility. Multivariable regression analyses were used to assess potential risk factors for CR and ESBL-producing E. coli carriage. Overall, CR and ESBL-producing E. coli were detected in 56% and 10% of all fecal samples, respectively. The odds of CR E. coli carriage were greater among dogs at households that lived within a 5 km radius of more than 5 commercial food animal facilities (OR 1.72, 95% CI 1.15-2.58) and lower among dogs living at households that used antimicrobials for their animal(s) based on veterinary/pharmacy recommendation (OR 0.18, 95% CI 0.04-0.96). Increased odds of canine ESBL-producing E. coli carriage were associated with recent antimicrobial use in any household animal (OR 2.69, 95% CI 1.02-7.10) and purchase of antimicrobials from pet food stores (OR 6.83, 95% CI 1.32-35.35). Food animals at households that owned more than 3 species (OR 0.64, 95% CI 0.42-0.97), that used antimicrobials for growth promotion (OR 0.41, 95% CI 0.19-0.89), and that obtained antimicrobials from pet food stores (OR 0.47, 95% CI 0.25-0.89) had decreased odds of CR E. coli carriage, while food animals at households with more than 5 people (OR 2.22, 95% CI 1.23-3.99) and located within 1 km of a commercial food animal facility (OR 2.57, 95% CI 1.08-6.12) had increased odds of ESBL-producing E. coli carriage. Together, these results highlight the complexity of antimicrobial resistance among domestic animals in this setting.

Caretaker knowledge, attitudes, and practices (KAP) and carriage of extended-spectrum beta-lactamase-producing E. coli (ESBL-EC) in children in Quito, Ecuador.

BACKGROUND: The rapid spread of extended-spectrum beta-lactamase-producing E. coli (ESBL-EC) is an urgent global health threat. We examined child caretaker knowledge, attitudes, and practices (KAP) towards proper antimicrobial agent use and whether certain KAP were associated with ESBL-EC colonization of their children. METHODS: Child caretakers living in semi-rural neighborhoods in peri-urban Quito, Ecuador were visited and surveyed about their KAP towards antibiotics. Fecal samples from one child (less than 5 years of age) per household were collected at two time points between July 2018 and May 2019 and screened for ESBL-EC. A repeated measures analysis with logistic regression was used to assess the relationship between KAP levels and child colonization with ESBL-EC. RESULTS: We analyzed 740 stool samples from 444 children living in households representing a range of environmental conditions. Of 374 children who provided fecal samples at the first household visit, 44 children were colonized with ESBL-EC (11.8%) and 161 were colonized with multidrug-resistant E. coli (43%). The prevalences of ESBL-EC and multidrug-resistant E. coli were similar at the second visit (11.2% and 41.3%, respectively; N = 366). Only 8% of caretakers knew that antibiotics killed bacteria but not viruses, and over a third reported that they "always" give their children antibiotics when the child's throat hurts (35%). Few associations were observed between KAP variables and ESBL-EC carriage among children. The odds of ESBL-EC carriage were 2.17 times greater (95% CI: 1.18-3.99) among children whose caregivers incorrectly stated that antibiotics do not kill bacteria compared to children whose caregivers correctly stated that antibiotics kill bacteria. Children from households where the caretaker answered the question "When your child's throat hurts, do you give them antibiotics?" with "sometimes" had lower odds of ESBL-EC carriage than those with a caretaker response of "never" (OR 0.48, 95% CI 0.27-0.87). CONCLUSION: Caregivers in our study population generally demonstrated low knowledge regarding appropriate use of antibiotics. Our findings suggest that misinformation about the types of infections (i.e. bacterial or viral) antibiotics should be used for may be associated with elevated odds of carriage of ESBL-EC. Understanding that using antibiotics is appropriate to treat infections some of the time may reduce the odds of ESBL-EC carriage. Overall, however, KAP measures of appropriate use of antibiotics were not strongly associated with ESBL-EC carriage. Other individual- and community-level environmental factors may overshadow the effect of KAP on ESBL-EC colonization. Intervention studies are needed to assess the true effect of improving KAP on laboratory-confirmed carriage of antimicrobial resistant bacteria, and should consider community-level studies for more effective management.

Social and Environmental Determinants of Community-Acquired Antimicrobial-Resistant Escherichia coli in Children Living in Semirural Communities of Quito, Ecuador.

Extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL), a family of bacteria that includes Escherichia coli, have emerged as a global health threat. This study examined risks associated with carriage of third-generation cephalosporin-resistant (3GC-R) E. coli, including ESBL-producing, multidrug-resistant, and extensively drug-resistant (XDR) strains in children living in semirural parishes of Quito, Ecuador. We conducted a longitudinal study with two cycles of sampling (N = 374, N = 366) that included an analysis of child fecal samples and survey questions relating to water, sanitation, and hygiene, socioeconomic status, household crowding, and animal ownership. We used multivariate regression models to assess risk factors associated with a child being colonized. Across the two cycles, 18.4% (n = 516) of the 3GC-R isolates were ESBL-producing E. coli, and 40.3% (n = 516) were XDR E. coli. Children living in households that owned between 11 and 20 backyard animals had an increased odds of being colonized with XDR E. coli (odds ratio [OR] = 1.94, 95% confidence interval [CI]: 1.05-3.60) compared with those with no animals. Households that reported smelling odors from commercial poultry had increased odds of having a child positive for XDR E. coli (OR = 1.72, 95% CI: 1.11-2.66). Our results suggest that colonization of children with antimicrobial-resistant E. coli is influenced by exposure to backyard and commercial livestock and poultry. Future studies should consider community-level risk factors because child exposures to drug-resistant bacteria are likely influenced by neighborhood and regional risk factors.