Healthy People 2030 aims to decrease low-risk cesarean delivery rates to 23.6% in the United States. In 2023, the national rate was 26.6%, though rates vary widely by state and hospital. This suggests a need for localized geographic estimates to identify places with higher burden. We modeled 2023 low-risk cesarean delivery rates by county of birth using birth certificate data and hierarchical Bayesian models that spatially smooth unstable estimates. We found considerable variation in rates, with county rates ranging from 5.8% to 53.4%. Counties in the West had lower rates than those in the Midwest, South, and Northeast. County rates increased with urbanicity. Only 47.7% (985) of counties had rates meeting the Healthy People 2030 target.

SARS-CoV-2 population-based seroprevalence surveys are useful for estimating the extent of SARS-CoV-2 infections, which may be underestimated by COVID-19 case counts. Surveys conducted in October 2020 in four Nigerian states showed that SARS-CoV-2 seroprevalence ranged from 9.3% in Gombe (northeast) to 25.2% in Enugu (southeast) after the first COVID-19 wave, more than 100 and 700 times higher than the official number of COVID-19 cases in these two states, respectively. We conducted a serosurvey after the second COVID-19 wave to evaluate the extent of SARS-CoV-2 infections, attitudes to COVID-19 vaccines, and COVID-19 vaccination coverage in two regions of Nigeria. Using the World Health Organization (WHO) Unity protocol, 34 enumeration areas (EAs) each in the Federal Capital Territory (FCT) (Northcentral Zone) and Kano State (Northwest Zone) were sampled in June 2021, using probability proportional to estimated size; 20 households in one EA were randomly selected. All consenting and assenting members of a household were asked about risk behaviors; adults who were 18 years and above (the eligible population for COVID-19 vaccination in Nigeria) responded to questions on COVID-19 vaccine attitudes and receipt. Blood and nasal/oropharyngeal samples were taken from all consenting and assenting household members. Blood samples collected were tested with the Luminex xMAP(R) SARS-CoV-2 Multi-Antigen IgG Assay and swabs by reverse-transcriptase-PCR (RT-PCR). Overall response rates were 76.8% in the FCT (n = 1,505 blood draws) and 80.4% in Kano State (n = 2,178 blood draws). Following the second COVID-19 wave in Nigeria, more than 40% of residents in the FCT (40.3%, 95% CI: 34.7-45.9) and Kano State (42.6%, 95% CI: 39.4-45.8) had evidence of prior SARS-CoV-2 infection. There were no active SARS-CoV-2 infections detected by RT-PCR in either the FCT or Kano State. In the FCT and Kano State, 3.4% and 1.6% of people surveyed reported receipt of any COVID-19 vaccine, three months after vaccines were available in country. In the FCT, 77.5% of adults were aware of COVID-19 vaccines, of whom 46.9% reported willingness to receive them. In Kano State, 48.7% of adults were aware of COVID-19 vaccines, of whom 61.1% were willing to receive them. In both regions, about 84% of those reporting unwillingness to accept COVID-19 vaccines cited concerns over vaccine safety. "Serosurvey findings revealed that SARS-CoV-2 infection was far more widespread in both the Federal Capital Territory and Kano State than indicated by reported case numbers. Despite high awareness, COVID-19 vaccine uptake remained low, primarily due to concerns about vaccine safety. These results highlight the urgent need for targeted risk communication to address vaccine hesitancy and improve coverage. Serosurveys provide valuable insights that can guide public health interventions and future pandemic preparedness in Nigeria."

The objective of this analysis is to examine characteristics of very preterm (VPT), very low birth weight (VLBW) infants not admitted to neonatal intensive care units (NICU). In this cross-sectional study assessing VPT (<32 weeks gestation) and VLBW (<1500 grams) infants, we used birth records from the National Vital Statistics System, 2021. Crude and adjusted prevalence ratios (aPR) with modified Poisson regression models were used to calculate prevalence of infants not admitted to the NICU by selected characteristics. Among 38,693 VPT, VLBW infants, 10% were not admitted to the NICU. In the adjusted model, characteristics associated with a higher prevalence of not being admitted to the NICU compared with analytical reference groups included non-Hispanic Native Hawaiian/Other Pacific Islander (aPR = 1.61;95% confidence interval [CI]:1.13-2.29), gestational age 22-24 weeks (aPR = 1.17;CI:1.08-1.26), vaginal delivery (aPR = 1.83;CI:1.73-1.94), and 5-minute Apgar score of 0-3 (aPR = 3.48;CI:3.18-3.82). Exploration of reasons infants were not admitted to the NICU may elucidate strategies to address barriers.

BACKGROUND: Improved causes of death (CoD) understanding in low- and middle-income countries is needed to reduce child mortality. Compared to full autopsy, minimally invasive tissue sampling (MITS), using transcutaneous needle sampling, is a feasible, socially acceptable, and validated method. We aimed to quantify the additional contribution of MITS to CoD attribution based on clinical records and inpatient research data with intensive patient characterisation. METHODS: We enrolled children aged seven days to 59 months who died while on admission for acute illness and/or severe malnutrition to Queen Elizabeth Central Hospital in Blantyre, Malawi. Standard MITS procedures included histologic, immunohistochemical, and microbiologic testing. Phase 1 CoD determination was based on medical records alone, Phase 2 also included research data, and Phase 3 included all data, including from MITS. RESULTS: We enrolled 29 children. Based on clinical notes alone (Phase 1), we identified 60 causal and 39 contributing conditions. Of the 45 (45%) infectious conditions, pathogens were identified in 15 (33%). Only one patient's (3%) CoD was unchanged compared to including all data (Phase 3). Further, we identified 69 new (n = 43) or adjusted (n = 26) diagnoses among 28 cases (97%); the majority were undernutrition-related (n = 22, 32%) or infectious (n = 41, 59%) conditions. Overall, the majority of final Phase 3 conditions were also undernutrition-related (n = 46, 32%) or infectious (n = 61, 43%) and a pathogen was identified in 54 (89%) of the infectious conditions. Klebsiella pneumoniae was the most prevalent aetiology in both pneumonia and sepsis. CONCLUSIONS: The addition of MITS to clinical and inpatient research data led to almost all (97%) of cases receiving new and/or refined diagnoses, including microbe identification in infectious conditions. Pathogens not specifically addressed by current clinical guidelines, such as Klebisiella pneumoniae, were commonly identified. Our findings support the utility of MITS to understand CoD even after thorough clinical characterisation of children during hospitalisation.

INTRODUCTION: Significant differences exist in the risk of diabetes and diabetes-related complications by income level in the United States. We assessed 1) to what extent medical expenditures in total and by health service type differ by income levels, and 2) how demographic and socioeconomic factors and health status are associated with these differences. METHODS: Data from the 2017 through 2021 Medical Expenditure Panel Survey were analyzed to estimate annual per-person medical expenditures for adults with diabetes. These expenditures were categorized by service type (inpatient, outpatient, prescription, home health care services, emergency department, or other) and compared across income groups based on the federal poverty level (FPL): poor (<125% FPL), low (125% to <200% FPL), middle (200% to <400% FPL), and high (>/=400% FPL). One-way analysis of variance was used to test group differences, and a regression-based decomposition identified factors driving expenditure disparities. All expenditures were adjusted to 2021 US dollars. RESULTS: Mean total medical expenditures were significantly higher for the poor-income group compared with the low-income, middle-income, and high-income groups, though no significant differences were observed among the latter 3 groups. Prescription drugs and home health care services in the poor-income group accounted for most of this difference. Key factors associated with the higher expenditures in this group included elevated disability rates, poorer physical health status, and dual Medicaid-Medicare coverage. CONCLUSION: Adults with diabetes from the poorest households incurred the highest medical expenditures, largely driven by poor physical health and higher rates of disability. Reducing disability and improving health outcomes for this group may help lower their medical expenses.

IntroductionBreast cancer remains a leading cause of cancer-related morbidity and mortality in sub-Saharan Africa, with Uganda experiencing a reported 5% annual increase in cases. Alarmingly, 87% of women in Uganda present with advanced-stage disease that is less responsive to treatment, contributing to the region's disproportionately low survival rate. Early breast cancer detection will be the fundamental intervention to reverse the mortality resulting from breast cancer in Uganda. This study aims to enhance breast cancer screening and early detection in Ugandan women who are at risk through innovative use of quantitative MRI to differentiate between benign and malignant breast lesions for women at risk.MethodsThe study prospectively recruited women at risk of breast cancer who underwent breast ultrafast DCE-MRI from July 2023 to April 2024. A 3.0-T MRI system with a16 channel breast dedicated coil was used with scan durations of up to 10 min. The T1 weighted pre-contrast, T1 weighted post-contrast, T1 weighted dynamic subtracted and Maximum Intensity projection (MIP) sequences were acquired and the histology blinded pharmacokinetic analysis for the breast lesion was done. The initial area under the curve in 30 s after contrast injection (iAUC30), MaxSlope, K(trans), BAT, and υ(e) were calculated and used to assess the diagnostic performance.ResultsA total of 52 women were recruited and imaged and 36 lesions were found. Unlike the MaxSlope, K(trans), BAT and υ(e) the iAUC30 values exhibited significant differences between benign and malignant lesions with a P-value <.005 and the area under the ROC curve (iAUC30) was 0.9147. The sensitivity, specificity, PPV and NPV of MRI using histology as the gold standard at 95% confidence interval were 70%, 100%, 100% and 73.9% respectively.ConclusionsAbbreviated DCE-MRI protocols with quantitative analysis can effectively differentiate malignant from benign breast lesions with improved compliance and can be adopted as a model of breast cancer screening and early detection for women at risk.

BACKGROUND: Cervical cancer is the fourth most common cancer among women globally, disproportionately affecting those in low- and middle-income countries (LMICs). In 2020, World Health Organization (WHO) Member States endorsed the 2030 Global Strategy toward Elimination of Cervical Cancer, recommending expanded access to human papillomavirus (HPV) vaccination. However, gaps remain in understanding how LMICs can sustain high HPV vaccine coverage. Tanzania, an early adopter among LMICs, introduced HPV vaccination into the national immunization schedule for 14-year-old girls in 2018 and achieved >90 % two-dose coverage by 2023. This study evaluated HPV vaccine program implementation in Tanzania, capturing stakeholder perspectives on barriers, facilitators, and recommendations. METHODS: Stakeholders were interviewed in April 2024 in a concurrent mixed-methods evaluation. Participants included national and subnational immunization staff (n = 18), and health workers, teachers, and community influencers (n = 80). Four of 31 regions were purposively selected based on criteria including first-dose HPV coverage (2020-2022) and urban/rural distribution. Two health facilities were randomly selected from a list of facilities in each region, along with two schools administering the vaccine from each facility's catchment area. Quantitative data were analyzed descriptively in STATA v.18, and qualitative data analyzed in ATLAS.ti Web (v19.3.1). RESULTS: Political support, quality improvement cycles, and integration with existing systems were identified as contributing to program success. Funding gaps and staff shortages-particularly in regions with low HPV vaccination coverage-were among the reported barriers, along with poor coordination between health and education sectors and low community awareness. Recommendations included increasing government funding, strengthening cross-sector collaboration, training stakeholders, and expanding dissemination channels to improve demand and address vaccine hesitancy. CONCLUSIONS: Tanzania's experience offers lessons for HPV vaccination in similar contexts. Addressing key barriers through increased funding, improved coordination, and enhanced community engagement could improve HPV vaccination implementation in Tanzania and elsewhere, contributing to global cervical cancer elimination.

Researchers need enhanced analytical techniques to profile and characterize tissue and cellular proteomes in studying nanogram scale peptide samples. To meet this demand, nanoflow liquid chromatography (nLC) and mass spectrometry (MS) work has focused on method development, while improvements are made in new cell sorting and isolation instrumentation. In this article, we describe improvements in peptide and protein identifications using simple, cost-effective changes to common mass spectrometry procedures. We focused on procedures that used an Orbitrap instrument to analyze 1 nanogram of peptide material or less. We found protein identifications increased over 40% when applying lowered precursor intensity thresholds in data-dependent selection. We also demonstrate improvements in identifying late-eluting peptides using sample diluents containing n-dodecyl-β-D-maltoside (DDM). We also show lower nLC flow rates can enhance protein identifications over 20%. Finally, we report improvements of 18% in peptide identifications when multiple high-field asymmetric waveform ion mobility spectrometry (FAIMS) compensation voltages (CV) are applied within a single method. These simple modifications provide researchers with options to improve peptide detection in very limited or low concentration samples.

Exposure to phthalates is common and difficult to avoid. However, intake of long-chain n-3 polyunsaturated fatty acids (n3PUFAs) may ameliorate negative effects on ovarian reserve by exposure to phthalates as both are involved in key processes of ovarian function. Among 139 women attending a fertility center in the Environment and Reproductive Health (EARTH) Study (2004-2017), we evaluated whether associations between urinary phthalate biomarkers and antral follicle count (AFC) were modified by tertiles of serum α-linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). We used Poisson regression (for individual phthalate biomarkers) and quantile Q-computation (for mixtures) models adjusted for age, body mass index, prior smoking, number of urine samples and urinary specific gravity. We found that serum EPA + DHA levels modified the negative association of urinary phthalate biomarkers mixture with mean AFC (P for interaction = 0.23); sum of di(2-ethylhexyl) phthalate metabolites (∑DEHP) had the strongest effect modification (P interaction = 0.01). Specifically, phthalate biomarkers mixture and ∑DEHP were inversely related with AFC only among women in the low (P trend = 0.03 and < 0.001, respectively) and middle (P trend = 0.07 and 0.002) tertiles of serum EPA + DHA, but not among women in the high tertile (P trend = 0.56 and 0.93). No effect modifications were found by serum ALA. These findings suggest certain serum n3PUFAs may attenuate effects of phthalate exposure on ovarian reserve marker. Such interaction points toward select n3PUFAs as key modifiers of phthalate toxicity on ovarian health with potential implications for other women's reproductive health endpoints.

BACKGROUND: A Lyme disease (LD) vaccine is expected to become available soon. We aimed to understand recent trends in healthcare provider (HCP) willingness to recommend LD vaccination. METHODS: Cross-sectional surveys among HCPs were conducted in 2018 and 2022. We compared willingness to recommend LD vaccination by survey year and provider characteristics. RESULTS: Among 3005 HCPs, 70.5 % reported willingness to recommend LD vaccination. This proportion was lower in 2022 than in 2018 (68 % vs 73 %; p < 0.01) and did not differ significantly by provider medical specialty. More HCPs in states with high LD incidence were willing to recommend the vaccine compared to HCPs in neighboring or low-incidence states (p < 0.01). Vaccine safety was the most frequently reported consideration for recommending LD vaccination (73 %). CONCLUSIONS: HCP willingness to recommend LD vaccination decreased from 2018 to 2022. Vaccination education tailored to HCPs that address vaccine safety will be critical for a successful LD vaccination program.

BACKGROUND: Resistance of Plasmodium falciparum to sulfadoxine-pyrimethamine threatens the antimalarial effectiveness of intermittent preventive treatment during pregnancy (IPTp) with sulfadoxine-pyrimethamine (ITPp-SP) in sub-Saharan Africa. We updated an aggregated-data meta-analysis to assess the associations between sulfadoxine-pyrimethamine resistance and the effectiveness of IPTp-SP to inform policy. METHODS: We searched databases (Jan 1, 1990, to June 8, 2024) for observational studies or trials reporting data on malaria, low birthweight (<2500 g), anaemia, and other outcomes by IPTp-SP dose and matched these by year and location with studies that reported on molecular markers of sulfadoxine-pyrimethamine resistance. Studies including only women with HIV or combined interventions were excluded. We evaluated how sulfadoxine-pyrimethamine resistance influenced the adjusted risk ratio (aRR) between three and two doses of IPTp-SP for various outcomes using Poisson mixed-effects models that allowed for non-linear relationships. Initially, we performed a threshold analysis, stratified by region, to identify the resistance levels most predictive of altered effect of IPTp-SP doses on malaria parasitaemia at delivery (peripheral or placental parasitaemia by any test), our primary outcome. These resistance strata were then used in all subsequent models for other outcomes. All analyses were adjusted for malaria transmission intensity, HIV infection, percentage of paucigravidae, and insecticide-treated net use. Performance of models was evaluated using cross-validation. The trial was registered with PROSPERO (CRD42021250359). FINDINGS: Overall, 122 studies involving 148 693 participants were included. For west and central Africa (69 studies comprising 63 745 participants), very low resistance was categorised as a prevalence of the dihydropteroate synthase (dhps) Lys540Glu mutation in the parasite population of less than 4%, and low resistance as a prevalence of Lys540Glu of 4% or higher. In east and southern Africa (53 studies comprising 84 948 participants), moderate resistance was categorised as a prevalence of the Lys540Glu mutation of less than 60% combined with a prevalence of the Ala581Gly mutation of less than 5%, high resistance as a prevalence of Lys540Glu of 60% or higher combined with a prevalence of Ala581Gly of less than 5%, and very high resistance as a prevalence of the Lys540Glu mutation of 60% or higher combined with a prevalence of Ala581Gly of 5% or higher. There was a marked trend towards lower efficacy of IPTp-SP on reducing malaria infection with increasing resistance levels. In west and central Africa, when comparing three versus two doses, the aRR was 0·71 (95% CI 0·65-0·78) in areas with very low resistance and 0·83 (0·72-0·95) in areas with low resistance (p=0·0144 for the difference between dose-response curves in very low vs low resistance). For east and southern Africa, the same trend was observed: the aRR was 0·63 (95% CI 0·57-0·69) in areas with moderate resistance, 0·89 (0·82-0·96) in areas with high resistance, and 0·93 (0·85-1·01) in areas with very high resistance (p<0·0001 for dose-response curves differences between moderate vs high and moderate vs very high resistance). This pattern was not seen for low birthweight. When comparing three versus two doses in west and central Africa, the aRR was 0·58 (95% CI 0·48-0·68) in areas with very low resistance and 0·56 (0·44-0·68) in areas with low resistance (p=0·72 for dose-response curves very low vs low resistance). For east and southern Africa, the aRR was 0·75 (95% CI 0·52-0·98) in areas with moderate resistance, 0·73 (0·69-0·78) in areas with high resistance, and 0·75 (0·63-0·87) in areas with very high resistance (p=0·80 for dose-response curves moderate vs high resistance; p=0·90 for moderate vs very high resistance). Dose comparisons in some resistance strata were limited by sample size. INTERPRETATION: IPTp-SP antimalarial efficacy is greatly reduced in very high resistance areas. However, it remains effective at reducing low birthweight in these areas, possibly through non-malaria effects on fetal growth. While IPTp-SP use should continue in high SP-resistance areas, alternative malaria preventive strategies are urgently needed in these areas. FUNDING: WHO and WorldWide-Antimalarial-Resistance-Network.

BACKGROUND: Hormonal contraceptive use by women with inflammatory bowel disease (IBD) might affect risk of adverse outcomes or contraceptive effectiveness. Our objective was to update a previous systematic review on the safety and effectiveness of contraceptive use among women with IBD. METHODS: We searched multiple databases from inception through July 15, 2024 for articles on contraception and IBD. Outcomes were IBD disease activity or relapse, other adverse health outcomes, and oral contraceptive (OC) effectiveness. We assessed risk of bias for each study and certainty of evidence for most outcomes. RESULTS: Fifteen articles met our inclusion criteria; 8 were new. Twelve had high risk of bias and three moderate risk. One cohort study found lower odds of IBD symptoms among hormonal contraceptive users compared with non-hormonal users, but higher odds of intestinal inflammation over one year. Nine cohort studies found inconsistent results regarding OC use and disease activity or relapse, with increased and decreased associations; most were not statistically significant. Two cohort studies found no statistically significant associations between OC use and VTE among IBD patients. One study found no statistically significant association between OC use and abnormal cervical smears. Two pharmacokinetic studies suggested no differences in plasma concentrations of steroid hormones after oral ingestion among participants with and without IBD. We found no evidence examining risk of osteoporosis or osteopenia among women with IBD using contraception. CONCLUSIONS: Limited evidence suggested inconsistent findings for increased risk of disease activity or relapse among women with IBD using hormonal contraception (very low certainty of evidence), no differences in other adverse events (very low certainty of evidence), and no differences in contraceptive hormone concentrations.

BACKGROUND: Achieving low incidence is one of WHO's key targets for the elimination of hepatitis C virus (HCV) infection. As progress in Georgia's hepatitis C elimination programme moves the country closer to reaching this target, tracking new cases of hepatitis C has become a priority. We aimed to estimate temporal trends in hepatitis C incidence among people who were tested more than once for hepatitis C in Georgia. METHODS: We conducted a retrospective cohort study in adults (aged ≥18 years) tested at least twice for antibodies against HCV (anti-HCV), with the first test being non-reactive, in Georgia from Jan 1, 2017, to Dec 31, 2023. Data were extracted from Georgian national hepatitis C screening and treatment databases on Jan 8, 2024. We calculated the incidence of anti-HCV seroconversion and current chronic HCV infections per 100 000 person-years and 95% CIs overall for 2017-23 and by year for 2017-22. For people who seroconverted but did not undergo testing to confirm current infection, we used multiple imputations to impute the status of current chronic HCV infection. To estimate the magnitude of change, we calculated incidence rate ratios (IRRs) with 95% CIs. FINDINGS: Among 1 264 181 adults with repeat anti-HCV testing during the study period, 519 936 (41·1%) were men and 744 245 (58·9%) were women. In total, 18 846 (1·5%) seroconverted to anti-HCV-reactive after a median follow-up time of 1025 days (IQR 503-1553). The overall incidence rate of anti-HCV seroconversion was 514 cases per 100 000 person-years (95% CI 506-521). The overall estimated incidence rate of current chronic HCV infection was 293 cases per 100 000 person-years (288-299). The annual incidence rate of anti-HCV seroconversion was 3·7 times lower in 2022 than in 2017, declining from 1399 cases per 100 000 person-years (1346-1454) to 377 cases per 100 000 person-years (361-394; IRR 0·27 [95% CI 0·25-0·29]). The annual incidence rate of chronic HCV infection was 4·6 times lower in 2022 than in 2017, declining from 935 cases per 100 000 person-years (892-981) to 205 cases per 100 000 person-years (193-217; IRR 0·22 [95% CI 0·20-0·24]). INTERPRETATION: We found a high but decreasing incidence rate of hepatitis C in Georgia among people tested more than once. The country should scale up preventive interventions to reduce incidence further and reach elimination targets. FUNDING: None. TRANSLATION: For the Georgian translation of the abstract see Supplementary Materials section.

BACKGROUND: This study aimed to evaluate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific binding and neutralizing antibody responses in healthcare workers (HCWs) who received coronavirus disease 2019 (COVID-19) vaccines, with or without postvaccination infections. METHODS: We conducted a prospective, observational cohort study of HCW in 2 hospitals in Manaus, Brazil. From 31 March through 31 May 2021, HCWs had nasal swabs collected and questionnaires administered weekly for 4 visits. Nasal swabs were tested for SARS-CoV-2 by real-time reverse transcription polymerase chain reaction (rRT-PCR). Blood specimens were obtained at visits 1 and 4 unless the HCW was found to be infected. If infected, a blood specimen was collected on days 14 and 28 after symptom onset or date of positive specimen, if asymptomatic. COVID-19 vaccination cards, state immunization records, and self-reported history of previous SARS-CoV-2 infection were obtained. Fully vaccinated HCWs who tested SARS-CoV-2 rRT-PCR positive were classified as postvaccination infections. RESULTS: A total of 771 HCWs were enrolled, with 73.7% (568/771) fully vaccinated. Anti-SARS-CoV-2 S1 immunoglobulin G and neutralizing antibody levels showed steep decay within the first 50 days after COVID-19 vaccination. HCWs with prior SARS-CoV-2 infection had slower visible decay after 50 days compared with those without prior infection. We identified 12 postvaccination infections of 16 HCWs who were SARS-CoV-2 rRT-PCR+, including 4 who also reported previous infection. Those positive for SARS-CoV-2 had lower baseline neutralizing antibody levels against Gamma and Delta variants preinfection (median log10 titers [interquartile range]: Gamma, 1.5 [3]; Delta: 0 [0.25]) compared to those who remained rRT-PCR negative (median log10 titers [interquartile range]: Gamma, 3 [2]; Delta, 1 [2]). CONCLUSIONS: Our findings highlight the importance of routine antibody surveillance, targeted boosters, and hybrid immunity in low and middle income countries. Timely booster doses for HCWs and the development of new vaccines against emerging variants can help sustain immunity and prevent workforce shortages, strengthening healthcare resilience in resource-limited settings.

OBJECTIVES: We investigated associations between occupational noise and gestational diabetes mellitus, pregnancy-related hypertension (including pre-eclampsia/eclampsia), preterm birth and small for gestational age (SGA) infants. METHODS: Data were analysed for 7889 singleton, live-born infants without major birth defects or chromosomal disorders and their mothers from the National Birth Defects Prevention Study from 1997 to 2011. Typical maternal occupational noise exposure in all jobs held from 1 month prior to conception through the end of pregnancy was estimated by expert rater and categorised as quiet (<60 A-weighted decibels (dBA)), low (60-75 dBA), moderate (76-84 dBA) or loud (>85 dBA). Multiple logistic regression was used to estimate associations (adjusted ORs and 95% CIs) between noise exposure levels and outcomes. RESULTS: Approximately 77.4% of pregnant workers had quiet levels of occupational noise exposure, 11.0%, 10.1% and 1.5% had low, moderate and loud exposure levels, respectively. Compared with quiet levels of noise, pregnant workers exposed to low levels of noise had decreased odds of delivering an SGA infant (adjusted OR (aOR)=0.72; 95% CI 0.53 to 0.99) and those exposed to moderate levels had increased odds of delivering an SGA infant (aOR=1.37; 95% CI 1.05 to 1.77). No other significant associations were observed. CONCLUSION: Maternal occupational noise exposure below the 85 dBA threshold recognised as hazardous may be associated with SGA among infants. Elevated point estimates (>1) were observed for the highest noise exposure category and all outcomes, though CIs were wide and statistical significance was not attained. Further research is warranted to address existing knowledge gaps.

BACKGROUND: Hypoxaemia predicts mortality at all levels of care, and appropriate management can reduce preventable deaths. However, pulse oximetry and oxygen therapy remain inaccessible in many primary care health facilities. We aimed to develop and validate a simple risk score comprising commonly evaluated clinical features to predict hypoxaemia in 2-59-month-old children with pneumonia. METHODS: Data from seven studies conducted in five countries from the Pneumonia Research Partnership to Assess WHO Recommendations (PREPARE) dataset were included. Readily available clinical features and demographic variables were used to develop a multivariable logistic regression model to predict hypoxemia (oxygen saturation <90%) at presentation to care. The adjusted log coefficients were transformed to derive the PREPARE hypoxemia risk score and its diagnostic value was assessed in a held-out, temporal validation dataset. The model and risk score were analysed by evaluating the area under the receiver operating characteristic curve (AUC), sensitivity and specificity. RESULTS: We included 14 509 children in the analysis; 9.8% (n=2515) were hypoxemic at presentation. The multivariable regression model to predict hypoxemia included age, sex, respiratory distress (nasal flaring, grunting and/or head nodding), lower chest indrawing, respiratory rate, body temperature and weight-for-age z-score. The model showed fair discrimination (AUC 0.70, 95% CI 0.67 to 0.73) and calibration in the validation dataset. The simplified PREPARE hypoxaemia risk score includes five variables: age, respiratory distress, lower chest indrawing, respiratory rate and weight-for-age z-score. CONCLUSION: The PREPARE hypoxemia risk score, comprising five easily available characteristics, has the potential to be used to identify hypoxemia in children with pneumonia with a fair degree of certainty for use in health facilities without pulse oximetry. Its implementation would require careful consideration to limit the burden of inappropriate referrals on patients and the health system. Further external validation in community settings in low- and middle-income countries is required.

OBJECTIVES: Rubella prevalence in the United States is low, and many positive immunoglobulin M (IgM) test results are likely false positive. We evaluated case classification and follow-up time spent on rubella-positive IgM test results from routine surveillance by the California Department of Public Health (CDPH). METHODS: We identified and abstracted data from rubella reports submitted to CDPH during January 1, 2018-December 31, 2022. CDPH uses a modified version of the 2013 Council of State and Territorial Epidemiologists (CSTE) rubella case definition to determine cases. The percentage of confirmed cases was the proportion of cases determined via CDPH's modification over reports adhering to the CSTE rubella case definition, calculated by test type and reason. We surveyed local public health staff to estimate person-time spent on report follow-up. RESULTS: We identified 801 suspected rubella reports. After investigation, CDPH confirmed 4 as cases and 797 as not cases; 467 (58.3%) were erroneously tested on the basis of test reason (immunity screening or ordered in error). Overall, 745 (93.0%) reports had IgM test results, 33 (4.1%) had an unknown test type, and 23 (2.9%) had a polymerase chain reaction test. Most erroneous reports (93.4%, 436/467) included only an IgM-positive test result. Mean time spent to investigate a suspected rubella report was 3.2 hours (range, <1-14.5 h). CONCLUSIONS: Most erroneous rubella reports submitted to CDPH during 2018-2022 included a positive IgM test result, highlighting limitations of using IgM test results to classify rubella cases. The CSTE rubella case definition should be revised to ensure consistent interpretation and classification of confirmed rubella cases.

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are persistent organic pollutants, many of which exhibit low in vivo clearance rates. The long-chain PFAS (≥6 perfluorinated carbons), due to low clearance rates, are often perceived to exert a higher toll on human health than short-chain PFAS. However, a comprehensive toxicological and epidemiological comparison of long- and short-chain PFAS is overdue, leaving significant data gaps and limitations. For the first time, this study investigated the quantitative relationship between overall PFAS fluorine structure (C-F bond), which includes the alkyl chain length as one component, and PFAS doses that trigger changes in rat blood-based clinical markers. Fifteen markers published by the National Toxicology Program (NTP) after 28-day exposure to 7 PFAS with both long- and short-chain perfluorinated alkyl structures were examined. The aim of this study was to (1) determine PFAS doses that trigger changes in the marker levels for hepatic, renal, cardiovascular, and metabolic systems and (2) use these doses in multiple linear regression models to examine relationship to variables describing PFAS chemical structures. Our findings showed a log-linear dependence of alterations in marker levels on PFAS fluorine structure, as measured in the number of alkyl carbon-fluorine (C-F) bonds. Each C-F bond affected the marker effect levels by 0.45 ± 0.01 mmol/kg-day. The variety of studied clinical markers suggests that PFAS exposures led to deviations in multiple biological pathways in the rat animal model, which may inform future research and regulatory decisions. | Perfluorinated carboxylic or sulfonic acids with linear chains of 4 to 10 carbons, known as perfluoroalkyl acids (PFAA)s, are types of PFAS commonly found in the environment.In a 28-day study by NTP, these PFAAs had dose-response effects in a panel of blood-based clinical markers in rats at specific doses.In regression models for individual clinical markers or a joint regression for all markers, these doses were strongly correlated with the number of carbon-fluorine bonds in the PFAAs.The resulting multiple linear regression (MLR) models provide a simple estimation tool for PFAAs’ exposure levels on blood-based clinical marker responses in rats. | eng

This paper explores population segments that differentiate people based on attitudes and perceptions about surveys and how those segments differ in survey participation intention. Our analysis finds 5 population segments across which general affinity toward surveys differs significantly. Survey Enthusiasts have high affinity toward surveys and underlying sense of civic responsibility to participate. Obligated Responders recognize the importance of participating, yet view surveys as an imposition. Reluctant Responders recognize survey participation as important but are moderately concerned about data misuse. The remaining 2 segments, the Disengaged and Shy Responders, have low affinities for survey participation. These findings suggest that effective survey designs should tailor different appeals and protocols to the motivations of a heterogeneous population. A multidimensional approach would parallel those approaches used in marketing where product differentiation and market segmentation help to successfully reach the consumer market. © 2025 The Author(s). Published by Oxford University Press on behalf of The World Association for Public Opinion Research. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site - for further information please contact journals.permissions@oup.com.

BACKGROUND: Nucleic acid-based assays are the diagnostic gold standard for filoviruses, including Ebola (EBOV) and Sudan (SUDV) viruses. However, outbreaks in areas with limited laboratory infrastructure highlight the need for simpler diagnostic tests that can be rapidly and safely used in the field. METHODS: We evaluated eight antigen rapid diagnostic tests (Ag-RDTs) for their ability to detect EBOV and SUDV. Analytical panels using virus cell slurries were used to assess limit of detection, and clinical samples were tested to determine sensitivity and specificity. RESULTS: Five Ag-RDTs detected EBOV and three detected SUDV, although clinical sensitivity was low (20-40 % for EBOV, 33 % for SUDV), improving only with higher viral loads. All assays demonstrated 100 % clinical specificity with no cross-reactivity. DISCUSSION: Although none of the evaluated Ag-RDTs are suitable for routine diagnosis, some may be useful in high viral load contexts such as cadaver testing. Our findings highlight the need to improve Ag-RDT sensitivity or develop high-sensitivity point-of-care molecular diagnostics.

OBJECTIVE: We sought to assess whether, among women with liver disease, there is an increased risk of adverse health effects with use of hormonal contraception (HC). METHODS: We conducted a systematic review of six databases from database inception through December 13, 2022. We searched for articles that examined changes in liver lesions and acute and chronic liver disease with use of HC or after discontinuation of HC. We assessed risk of bias for each study and certainty of evidence for all outcomes. RESULTS: Thirteen articles met inclusion criteria, one with low risk of bias and the others with high risk of bias: three studies (four articles) were of women with focal nodular hyperplasia (FNH), five studies were of hepatocellular adenoma (HCA) and four studies were of acute or chronic hepatitis. The size and/or number of FNH lesions were generally not influenced by HC use. HCA progression was generally higher among current combined oral contraception (COC) users than those who discontinued, and lesions were stable or regressed in most women who discontinued COC or used progestin-only contraception. Studies found that viral hepatitis generally did not progress or increase in severity with use of COC. CONCLUSION: Overall, a limited body of evidence suggested changes in FNH lesions were independent of hormonal contraceptive use. Estrogen-containing contraceptive method use was associated with HCA lesion progression; lesions generally remained stable with progestin-only contraceptive use. COC use did not increase progression or severity of disease among those with viral hepatitis. The certainty of evidence for all outcomes was very low. IMPLICATIONS: Liver conditions such as liver lesions, viral hepatitis, and cirrhosis are increasingly common in women of reproductive age. Information in this review can be used by health care providers when counseling women with liver disease about safe use of contraception.

OBJECTIVE: Increased antibiotic use (AU) has been reported globally during the COVID-19 pandemic despite low rates of bacterial co-infection. We assessed changes in AU during the COVID-19 pandemic in Indonesia and the Philippines. METHODS: We evaluated hospital-wide AU over 36 months in six hospitals, 3 in Indonesia and 3 in the Philippines. Intravenous antibiotics commonly used for respiratory conditions were selected and grouped for analysis. AU rates were calculated as monthly defined daily dose per 1000 patient-days or patient discharges. Median AU rates were compared from the pre-pandemic (March 2018-February 2020) and pandemic periods (March 2020-February 2021) using quantile regression to assess for statistical significance. Changes in AU during the COVID-19 pandemic were analyzed using interrupted time series analysis. RESULTS: Significant increases were noted in the median AU rate from the pre-pandemic to pandemic period of all antibiotics combined in 3/6 hospitals (percentage change, Δ, 12.5%-63.6%) and anti-pseudomonal antibiotics in 3/6 hospitals (Δ 51.5%-161.5%). In the interrupted time series analysis, an immediate increase (range: 125.40-1762) in the use of all included antibiotics combined was observed in 3/6 hospitals at the onset of the COVID-19 pandemic. One of these 3 hospitals experienced a statistically significant sustained increase, while another experienced a decrease over time. CONCLUSIONS: We observed significant increases in facility-wide inpatient AU during the COVID-19 pandemic in our participating hospitals in Indonesia and the Philippines. These findings reinforce the importance of antibiotic stewardship practices to optimize AU, especially during infectious disease pandemics.

The recognized burden of antimicrobial resistance (AR) is greatest in low- and middle-income countries (LMICs), but limitations in surveillance preclude accurate estimates of AR. We aimed to evaluate colonization in communities and hospitals across six LMICs for two clinically-important pathogens: extended-spectrum cephalosporin-resistant Enterobacterales (ESCrE) and carbapenem-resistant Enterobacterales (CRE). Participants in hospitals and communities provided rectal swabs or stool samples for ESCrE and CRE identification. Isolates recovered from selective agars underwent confirmatory identification and antibiotic susceptibility testing (AST) using Vitek(®) 2, MALDI-TOF, and/or disc diffusion testing. ESCrE and CRE were defined based on established breakpoints of phenotypic resistance to third-generation cephalosporins and carbapenems, respectively, to calculate prevalence of colonization. Community prevalence estimates were weighted to account for sampling design differences. A total of 10,139 participants across the 6 countries provided samples; 63% were females with a median age of 35 years (range: 0-99). Colonization with ESCrE in hospitals was high in all sites (range 34-84%). In communities, ESCrE colonization ranged from 22 to 77%. Prevalence of CRE colonization in hospitals ranged from 7 to 36% and in communities ranged from < 1 to 14%. These findings reveal a high burden of AR colonization in LMICs in both communities and hospitals. Cost-effective strategies to reduce AR colonization burden are needed in LMICs.

This study assessed resource allocation among registry activities, which may provide insight for efficient collection of high-quality cancer incidence data. We used a multimodal approach and purposively sampled 21 participating population-based cancer registries in the United States to ensure variation across several registries. The registries reported prospective staffing data and retrospective costing data, completing data collection from October 2021 to September 2022, reporting retrospective costing data for July 1, 2020, through June 30, 2021. From lessons learned from prior studies, we engaged participating registries early and throughout the study, ensuring the collection of meaningful, accurate quantitative data, as well as insights not captured quantitatively. Case volume is a major driver of registry costs. (On average, high-volume registries outspend low-volume registries by nearly 3x, annually). Upon examination of registry activities by case volume, we found that the two most resource-intensive registry activities are data acquisition and data processing, which may be addressed by innovations, such as electronic reporting and automation. Innovative data transfer and processing approaches could increase timeliness of data collection and reduce the labor resources required to process manually collected data. Registries adopting these innovations might achieve cost savings, which could make resources available to support other registry activities.

Mycoplasma pneumoniae is a common bacterial cause of respiratory infection and a leading cause of childhood community-acquired pneumonia (CAP). Increases in M. pneumoniae infection occur every 3-5 years. In the United States, M. pneumoniae prevalence decreased during and immediately after the COVID-19 pandemic. Information from 42 U.S. children's hospitals that provided information to the Pediatric Health Information System, a database of clinical and resource use information, was used to identify discharge diagnostic codes for 2018-2024 indicating M. pneumoniae infection. M. pneumoniae-associated CAP incidence among children aged ≤18 years was significantly higher in 2024 (12.5 per 1,000 hospitalizations) than during 2018-2023 (2.1). During the study period, an M. pneumoniae diagnostic code was listed in 11.5% of pediatric CAP hospitalizations, peaking at 53.8% in July 2024. Among pediatric M. pneumoniae CAP cases, the highest percentage occurred among children aged 6-12 years (42.6%), followed by children aged 2-5 years (25.7%) and 13-18 years (21.1%). The lowest occurred among those aged 12-23 months (6.4%) and 0-11 months (4.2%). M. pneumoniae infections in 2024 were not more severe than 2018-2023 infections, as assessed by length of hospitalization and percentage of patients admitted to an intensive care unit. The increase in M. pneumoniae infections in the United States in 2024 might be higher than previous periodic increases because the susceptible population was larger after sustained low incidence during and immediately after the COVID-19 pandemic. Health care providers should be aware of the periodicity of M. pneumoniae CAP and consider testing for this pathogen as a cause of respiratory illness among children of all ages.

Antiviral susceptibility of influenza viruses is monitored by the World Health Organization Global Influenza Surveillance and Response System. This study describes a global analysis of the susceptibility of influenza viruses to neuraminidase (NA) inhibitors (NAIs, oseltamivir, zanamivir, peramivir, laninamivir) and the cap-dependent endonuclease inhibitor (CENI, baloxavir) for three periods (May to May for 2020-2021, 2021-2022 and 2022-2023). In particular, global influenza activity declined significantly in 2020-2021 and 2021-2022 when compared to the pre-pandemic period of COVID-19. Combined phenotypic and NA sequence-based analysis revealed that the global frequency of seasonal influenza viruses with reduced or highly reduced inhibition (RI/HRI) by NAIs remained low, 0.09% (2/2224), 0.12% (27/23465) and 0.23% (124/53917) for 2020-2021, 2021-2022 and 2022-2023, respectively. As in previous years, NA-H275Y in A(H1N1)pdm09 viruses was the most frequent substitution causing HRI by oseltamivir and peramivir. Sequence-based analysis of polymerase acidic (PA) protein supplemented with phenotypic testing revealed low global frequencies of seasonal influenza viruses with reduced susceptibility (RS) to baloxavir, 0.07% (1/1376), 0.05% (9/18380) and 0.12% (48/39945) for 2020-2021, 2021-2022 and 2022-2023, respectively; commonly associated substitutions were PA-I38T/M/L. In Japan, the rate was 3.3% (16/488) during 2022-2023, with 11 A(H3N2) viruses having PA-I38T/M substitutions. For zoonotic viruses, 2.7% (3/111) contained substitutions, one each NA-H275Y, NA-S247N and NA-N295S, associated with RI/HRI NAI phenotypes, and none contained PA substitutions associated with RS to baloxavir. In conclusion, the great majority of seasonal and zoonotic influenza viruses remained susceptible to NAIs and CENI baloxavir.

INTRODUCTION: Sexual violence (SV) affects millions globally and has a well-documented bidirectional association with HIV. Post-exposure prophylaxis (PEP) is a critical, yet often underutilized, HIV prevention tool in post-SV care. Despite its potential impact to reduce HIV transmission, SV care remains an overlooked service delivery point for HIV prevention. The U.S. Centers for Disease Control and Prevention (CDC), as part of the President's Emergency Plan for AIDS Relief (PEPFAR), supports PEP provision within broader post-violence care (PVC) services. Understanding PEP utilization is crucial for optimizing service delivery and HIV prevention efforts. METHODS: Using Monitoring Evaluation and Reporting data from fiscal years 2018-2023, we conducted a descriptive analysis of clients who received PVC and SV services through CDC-supported programming in 14 sub-Saharan African countries. RESULTS: From 2018 to 2023, the annual number of clients receiving any PVC, and specifically SV, services increased by 233% (in 2018, n = 206,764; in 2023, n = 689,349) and 163% (in 2018, n = 42,848; in 2023, n = 112,838), respectively. Fewer than half of SV clients completed PEP (38% in 2018, n = 16,103; 31% in 2023, n = 35,118). Across all years combined, most SV clients (female: 185,414; male: 59,618) were aged 15-19 years. The age band and sex with the lowest proportion of clients completing PEP were males aged 15-19 (4%, n = 2296). CONCLUSIONS: The findings underscore a critical gap between the scaling of SV services and the completion of PEP within violence response programmes. Innovative implementation science approaches may help to identify and address barriers inhibiting effective PEP delivery and uptake within PVC service delivery programmes. Enhancing PEP uptake and completion can support mitigating the bidirectional relationship between violence and HIV acquisition, particularly among vulnerable populations like adolescents and young adults. Low PEP coverage also reflects missed opportunities, particularly among adolescent girls and young women, who experience disproportionate rates of HIV acquisition.

BACKGROUND: In Africa, for people with HIV on a dolutegravir-based regimen with a viral load of more than 1000 copies per mL despite enhanced adherence counselling, the appropriate course of action is uncertain. We aimed to evaluate the predicted effects of alternative antiretroviral regimen switching options in this population, including consideration of cost-effectiveness. METHODS: We used an existing individual-based model to simulate risk and experience of HIV in 100 000 adults alive between 1989 and 2076. Using sampling of parameter values, we created 1000 setting-scenarios, reflecting the uncertainty in assumptions and a range of settings similar to those seen in eastern, central, southern, and western Africa. For each setting-scenario, we predicted the outcomes from the three alternative policies for people with sustained viral load non-suppression on a dolutegravir-containing regimen from 2026: a switch to a protease inhibitor-based regimen (switch policy), a switch to a protease inhibitor-based regimen only if HIV drug resistance testing beforehand shows integrase inhibitor resistance (resistance test policy), and no switch with no HIV drug resistance test (no switch policy). We considered predicted outcomes over 10-year and 50-year periods from 2026, used a 3% discount rate, and a cost-effectiveness threshold of US$500 per disability-adjusted life-year (DALY) averted. Ritonavir-boosted darunavir costs $210 per year, and dolutegravir less than $20. We assumed a cost of HIV drug resistance testing of $200 and considered variations around this. For comparing policies, we calculated net DALYs, which account for the health consequences of differences in costs and provide a measure of the impact of a policy on overall population burden of disease. FINDINGS: Across setting-scenarios, there was a mean of 14 480 deaths per year (95% CI 13 750-15 210) over 50 years with a mean annual discounted cost of $103·2 million (95·8-106·5) with the switch policy in the context of having scaled to a setting with an adult population of 10 million in 2024. Compared with the switch policy, the no switch policy was predicted to lead to an overall increased number of DALYs incurred (mean 4400 per year, 95% CI 3200-5500), although it resulted in the lowest overall cost, with a difference in annual discounted costs of $5·1 million (95% CI 4·6-5·6) lower than the switch policy. The resistance test policy led to a similar risk of death and DALYs to the switch policy at a lower overall cost (difference in annual discounted costs $3·5 million per year, 95% CI 3·1-3·9), leading to 6900 (95% CI 5500-8200) fewer net DALYs per year. Net DALYs for the resistance test versus no switch policies were similar (-1000 net DALYs, 95% CI 400 to -2300). The incremental cost-effectiveness ratio when comparing the resistance test policy with the no switch policy was $376 per DALY averted; the switch policy was dominated. INTERPRETATION: Introduction of HIV drug resistance testing for people with sustained viral load non-suppression on dolutegravir-based antiretroviral therapy is likely to be cost-effective. We suggest that exploratory planning for increased access and scale-up of high-quality, low-cost drug resistance testing for the region is undertaken. FUNDING: Gates Foundation as part of the HIV Modelling Consortium.

BackgroundSchool food environments may play an important role in shaping children's dietary habits, health, and nutrition.ObjectivesThis study aimed to evaluate associations between the school food environment and nutrition among in-school adolescents in Ghana.MethodsData were collected in Ghana in 2022 in a national nutrition and health survey of adolescents attending junior (JHS) and senior high schools (SHS). Foods observed on campus or reported in the dietary recall were aggregated, a composite Adolescent Dietary Diversity Score (ADDS) was derived, and the proportion achieving minimum dietary diversity was estimated. Multi-level regression models were used to assess associations between a ranked school food environment score (FES) and nutrition outcomes.ResultsThe number of food groups served or available for purchase was 6.2 in JHS and 8.1 in SHS (P-value <.0001). The mean (95% CI) FES was 10.9 (10.1, 11.7) at JHS and 14.3 (13.6, 14.9) at SHS. ADDS ranged from 4.1 to 4.8 across strata. Higher FES was positively associated with ADDS and minimum dietary diversity among SHS students and negatively associated with anemia in girls and boys. Girls from high FES schools had 24% lower odds of anemia (OR: 0.76, 95% CI: 0.63, 0.93) while boys had 46% lower odds (OR: 0.54, 95% CI: 0.34, 0.84) compared to students in low FES schools.ConclusionsHigher FES was associated with greater dietary diversity among SHS students and lower odds of anemia in girls and boys, suggesting that the school food environment may play a role in determining nutrition outcomes. | The School Food Environment in Ghana is Related to Dietary Diversity and AnemiaPlain Language SummaryThe foods that children eat while at school have an important impact on their health and nutrition. We collected data among in-school girls and boys aged 10–19 years in Ghana. Students were asked what they had eaten in the last 24 h and were asked questions about their general food practices at school, such as what foods are included in school meals, what foods they typically bring to school, and what foods they buy at school. We also collected blood from students to test for anemia. School leaders were interviewed to better understand school programs and activities related to food and nutrition, including questions about the school meals program and food vendors present on campus. We used the information we gathered from these interviews to create a school food environment score. We found that, on average, students consumed fewer than 5 out of 10 food groups on a given day. We also found that senior high schools tended to have a larger variety of foods available and had a higher food environment score compared to junior high schools. In schools with higher food environment scores, students were more likely to eat a larger variety of foods and less likely to have anemia. These findings may be used to improve existing nutrition programs in Ghana and to design future programs focused on the health of school children. | eng

INTRODUCTION: Arthritis is a common chronic disease, affecting an estimated 53.2 million adults (21.2%) in the US. "Arthritis" is a general term, describing over 100 conditions with different etiologies, pathogeneses, symptoms, and treatments. Few studies have examined the prevalence and distribution of arthritis subtypes in the US. METHODS: We used National Health and Nutrition Examination Survey data from 2017 to March 2020 to estimate the prevalence of arthritis subtypes overall and by sociodemographic characteristics. RESULTS: The overall prevalence of any type of diagnosed arthritis among US adults aged 20 years or older in this study was 27.9% (67.1 million). Among adults with diagnosed arthritis, osteoarthritis (49.6%, 33.2 million) was the most common arthritis subtype, followed by rheumatoid arthritis (15.8%, 10.6 million) and psoriatic arthritis (1.4%, 1.0 million). More than 1 in 10 reported some other type of unlisted arthritis (11.5%, 7.7 million), and 1 in 5 did not know their arthritis subtype (21.6%, 14.4 million). Prevalence of not knowing arthritis type was approximately 1 in 4 for adults identifying as non-Hispanic Black (26.7%) or other Hispanic (29.5%) and for adults who reported low family income (26.7%) and was approximately 1 in 3 for adults identifying as Mexican American (31.9%), having less than a high school education (31.8%), or not having health insurance (36.1%). CONCLUSION: Understanding arthritis type is important for improving treatment, self-management, and health outcomes associated with arthritis. Improving organizational and personal health literacy are potential strategies that may reduce the prevalence of not knowing arthritis type.