Efficacy of Single-Dose Azithromycin for Ocular Chlamydial Infection: A Longitudinal Study.

Millions of doses of azithromycin are distributed each year for trachoma, yet the treatment efficacy of a single dose of azithromycin for ocular Chlamydia infection has not been well characterized. In this study, four villages in Niger received a mass azithromycin distribution for trachoma. All 426 children aged 0-5 years residing in the study villages were offered conjunctival swabbing every 6 months to test for ocular Chlamydia trachomatis. Among the children infected with ocular Chlamydia before treatment, 6% (95% CI: 2-15%) tested positive for ocular Chlamydia infection 6 months later, and 15% (95% CI: 7-28%) tested positive 12 months later. The most important predictor of post-treatment ocular Chlamydia infection was pretreatment ocular Chlamydia infection (relative risk: 3.5, 95% CI: 1.3-9.4). Although the 6-monthly monitoring schedule was suboptimal for testing the treatment efficacy of an antibiotic, these findings are nonetheless consistent with high treatment efficacy of a single dose of azithromycin and suggest that additional interventions might be most effective if targeted to those children infected prior to treatment.

Use of Large Language Models to Assess the Likelihood of Epidemics From the Content of Tweets: Infodemiology Study.

BACKGROUND: Previous work suggests that Google searches could be useful in identifying conjunctivitis epidemics. Content-based assessment of social media content may provide additional value in serving as early indicators of conjunctivitis and other systemic infectious diseases. OBJECTIVE: We investigated whether large language models, specifically GPT-3.5 and GPT-4 (OpenAI), can provide probabilistic assessments of whether social media posts about conjunctivitis could indicate a regional outbreak. METHODS: A total of 12,194 conjunctivitis-related tweets were obtained using a targeted Boolean search in multiple languages from India, Guam (United States), Martinique (France), the Philippines, American Samoa (United States), Fiji, Costa Rica, Haiti, and the Bahamas, covering the time frame from January 1, 2012, to March 13, 2023. By providing these tweets via prompts to GPT-3.5 and GPT-4, we obtained probabilistic assessments that were validated by 2 human raters. We then calculated Pearson correlations of these time series with tweet volume and the occurrence of known outbreaks in these 9 locations, with time series bootstrap used to compute CIs. RESULTS: Probabilistic assessments derived from GPT-3.5 showed correlations of 0.60 (95% CI 0.47-0.70) and 0.53 (95% CI 0.40-0.65) with the 2 human raters, with higher results for GPT-4. The weekly averages of GPT-3.5 probabilities showed substantial correlations with weekly tweet volume for 44% (4/9) of the countries, with correlations ranging from 0.10 (95% CI 0.0-0.29) to 0.53 (95% CI 0.39-0.89), with larger correlations for GPT-4. More modest correlations were found for correlation with known epidemics, with substantial correlation only in American Samoa (0.40, 95% CI 0.16-0.81). CONCLUSIONS: These findings suggest that GPT prompting can efficiently assess the content of social media posts and indicate possible disease outbreaks to a degree of accuracy comparable to that of humans. Furthermore, we found that automated content analysis of tweets is related to tweet volume for conjunctivitis-related posts in some locations and to the occurrence of actual epidemics. Future work may improve the sensitivity and specificity of these methods for disease outbreak detection.

Mass Azithromycin Distribution to Prevent Child Mortality in Burkina Faso: The CHAT Randomized Clinical Trial.

Importance: Repeated mass distribution of azithromycin has been shown to reduce childhood mortality by 14% in sub-Saharan Africa. However, the estimated effect varied by location, suggesting that the intervention may not be effective in different geographical areas, time periods, or conditions. Objective: To evaluate the efficacy of twice-yearly azithromycin to reduce mortality in children in the presence of seasonal malaria chemoprevention. Design, Setting, and Participants: This cluster randomized placebo-controlled trial evaluating the efficacy of single-dose azithromycin for prevention of all-cause childhood mortality included 341 communities in the Nouna district in rural northwestern Burkina Faso. Participants were children aged 1 to 59 months living in the study communities. Interventions: Communities were randomized in a 1:1 ratio to receive oral azithromycin or placebo distribution. Children aged 1 to 59 months were offered single-dose treatment twice yearly for 3 years (6 distributions) from August 2019 to February 2023. Main Outcomes and Measures: The primary outcome was all-cause childhood mortality, measured during a twice-yearly enumerative census. Results: A total of 34 399 children (mean [SD] age, 25.2 [18] months) in the azithromycin group and 33 847 children (mean [SD] age, 25.6 [18] months) in the placebo group were included. A mean (SD) of 90.1% (16.0%) of the censused children received the scheduled study drug in the azithromycin group and 89.8% (17.1%) received the scheduled study drug in the placebo group. In the azithromycin group, 498 deaths were recorded over 60 592 person-years (8.2 deaths/1000 person-years). In the placebo group, 588 deaths were recorded over 58 547 person-years (10.0 deaths/1000 person-years). The incidence rate ratio for mortality was 0.82 (95% CI, 0.67-1.02; P = .07) in the azithromycin group compared with the placebo group. The incidence rate ratio was 0.99 (95% CI, 0.72-1.36) in those aged 1 to 11 months, 0.92 (95% CI, 0.67-1.27) in those aged 12 to 23 months, and 0.73 (95% CI, 0.57-0.94) in those aged 24 to 59 months. Conclusions and Relevance: Mortality in children (aged 1-59 months) was lower with biannual mass azithromycin distribution in a setting in which seasonal malaria chemoprevention was also being distributed, but the difference was not statistically significant. The study may have been underpowered to detect a clinically relevant difference. Trial Registration: ClinicalTrials.gov Identifier: NCT03676764.

Azithromycin during Routine Well-Infant Visits to Prevent Death.

BACKGROUND: Mass distribution of azithromycin to children 1 to 59 months of age has been shown to reduce childhood all-cause mortality in some sub-Saharan African regions, with the largest reduction seen among infants younger than 12 months of age. Whether the administration of azithromycin at routine health care visits for infants would be effective in preventing death is unclear. METHODS: We conducted a randomized, placebo-controlled trial of a single dose of azithromycin (20 mg per kilogram of body weight) as compared with placebo, administered during infancy (5 to 12 weeks of age). The primary end point was death before 6 months of age. Infants were recruited at routine vaccination or other well-child visits in clinics and through community outreach in three regions of Burkina Faso. Vital status was assessed at 6 months of age. RESULTS: Of the 32,877 infants enrolled from September 2019 through October 2022, a total of 16,416 infants were randomly assigned to azithromycin and 16,461 to placebo. Eighty-two infants in the azithromycin group and 75 infants in the placebo group died before 6 months of age (hazard ratio, 1.09; 95% confidence interval [CI], 0.80 to 1.49; P = 0.58); the absolute difference in mortality was 0.04 percentage points (95% CI, -0.10 to 0.21). There was no evidence of an effect of azithromycin on mortality in any of the prespecified subgroups, including subgroups defined according to age, sex, and baseline weight, and no evidence of a difference between the two trial groups in the incidence of adverse events. CONCLUSIONS: In this trial conducted in Burkina Faso, we found that administration of azithromycin to infants through the existing health care system did not prevent death. (Funded by the Bill and Melinda Gates Foundation; CHAT ClinicalTrials.gov number, NCT03676764.).

Practice Patterns in the Initial Management of Herpes Zoster Ophthalmicus in the United States.

PURPOSE: The aims of this study were to examine the trends in the initial management of herpes zoster ophthalmicus (HZO) in the United States from 2010 to 2018 and compare them with the treatment preferences of corneal specialists. METHODS: A retrospective, observational deidentified cohort study was conducted on individuals enrolled in the OptumLabs Data Warehouse who had a new diagnosis of HZO from 1/1/2010 to 12/31/2018. An online survey ascertaining HZO management perspectives was distributed to The Cornea Society listserv. The main outcome assessed was proportion of cases with systemic antiviral prescriptions, eye care provider involvement, and follow-up visits after the initial HZO diagnosis. RESULTS: Approximately 50% of patients received systemic antivirals the day of initial HZO diagnosis or within 7 days (45.6% and 53.7%, respectively). Most initial diagnoses were made by ophthalmologists (45.0%), followed by optometrists (19.2%). Referral rate to ophthalmology within a year of initial diagnosis was 38.6%. 48.7% cases had at least 1 follow-up visit with any type of provider within 30 days. Our survey of corneal specialists found 97% would prescribe systemic antivirals to those with ocular involvement, but 66% would prescribe antivirals to those without ocular or eyelid involvement. Seventy percent supported all patients having follow-up with an eye care provider within a month. CONCLUSIONS: HZO antiviral therapies seem to be underprescribed in the United States, referral rates to ophthalmology are low, and follow-up is suboptimal, which are not aligned with recommendations from corneal specialists. More research is needed to establish standardized guidelines for treatment, referral, and follow-up with ophthalmology for HZO.

Pathogen Surveillance for Acute Infectious Conjunctivitis.

Importance: Acute infectious conjunctivitis is a common ocular condition with major public health consequences. Objective: To assess regional variations and microbial etiologies of acute infectious conjunctivitis to guide treatment. Design, Setting, and Participants: In this cross-sectional study, patients with presumed acute infectious conjunctivitis were enrolled in the study at 5 sites (Honolulu, Hawaii; Los Angeles, San Francisco, and San Diego, California; and Petah-Tikva, Israel) from March 2021 to March 2023. Patients with allergic or toxic conjunctivitis were excluded. Main Outcomes and Measures: Pathogens were identified by unbiased RNA deep sequencing. Results: In all, 52 patients (mean [range] age, 48 [7-80] years; 31 females [60%]) were enrolled at 5 sites (6 patients from Honolulu, 9 from San Diego, 11 from Los Angeles, 13 from San Francisco, and 13 from Petah-Tikva). RNA deep sequencing detected human adenovirus species D in one-quarter of patients (13 of 52). A wide range of pathogens, including human coronavirus 229E, SARS-CoV-2, and herpes simplex virus type 1, was also identified, as well as several bacteria and fungi. Moreover, 62% (32 of 52) of patients presented with purulent discharge, while only 8% (4 of 52) of patients had confirmed bacterial pathogens. Conclusion and Relevance: In this cross-sectional study, pathogens associated with acute infectious conjunctivitis varied between all 5 sites in the US and Israel. Purulent discharge was a common presenting sign in this study, with a low specificity for bacteria-associated conjunctivitis, suggesting that further diagnostic workup may be necessary to inform antibiotic stewardship. Additional research on cost-effectiveness of using RNA deep sequencing is needed to ascertain whether it is better to monitor patients clinically until resolution of disease.

Temporal Trends in Phenotypic Macrolide and Nonmacrolide Resistance for Streptococcus pneumoniae Nasopharyngeal Samples Up to 36 Months after Mass Azithromycin Administration in a Cluster-Randomized Trial in Niger.

Azithromycin mass drug administration decreases child mortality but also selects for antibiotic resistance. Herein, we evaluate macrolide resistance of nasopharyngeal Streptococcus pneumoniae after azithromycin MDA. In a cluster-randomized trial, children 1-59 months received azithromycin or placebo biannually. Fifteen villages from each arm were randomly selected for antimicrobial resistance testing, and 10-15 randomly selected swabs from enrolled children at each village were processed for S. pneumoniae isolation and resistance testing. The primary prespecified outcome was macrolide resistance fraction for azithromycin versus placebo villages at 36 months. Secondary non-prespecified outcomes were comparisons of azithromycin and placebo for: 1) macrolide resistance at 12, 24, and 36 months; 2) nonmacrolide resistance at 36 months; and 3) suspected-erm mutation. At 36 months, 423 swabs were obtained and 322 grew S. pneumoniae, (azithromycin: 146/202, placebo: 176/221). Mean resistance prevalence was non-significantly higher in treatment than placebo (mixed-effects model: 14.6% vs. 8.9%; OR = 2.0, 95% CI: 0.99-3.97). However, when all time points were evaluated, macrolide resistance prevalence was significantly higher in the azithromycin group (ß = 0.102, 95% CI: 0.04-0.167). For all nonmacrolides, resistance prevalence at 36 months was not different between the two groups. Azithromycin and placebo were not different for suspected-erm mutation prevalence. Macrolide resistance was higher in the azithromycin group over all time points, but not at 36 months. Although this suggests resistance may not continue to increase after biannual MDA, more studies are needed to clarify when MDA can safely decrease mortality and morbidity in lower- and middle-income countries.

Anthropometric Differences in Community- Versus Clinic-Recruited Infants Participating in a Trial of Azithromycin for Prevention of Childhood Mortality in Burkina Faso.

Clinic-based recruitment for preventative interventions for child health may select for healthier populations compared with community-based outreach. Nutritional status during infancy as measured by anthropometry is predictive of mortality, growth faltering later in life, and poor cognitive development outcomes. We evaluated baseline differences in infant nutritional status among children recruited directly in their community versus clinic recruitment among infants participating in a trial of azithromycin compared with placebo for prevention of mortality in three districts of Burkina Faso. Infants between 5 and 12 weeks of age were recruited in their community of residence via vaccine outreach teams or in primary health-care clinics during vaccine clinics. Weight, height, and mid upper arm circumference were measured. We used linear and logistic regression models to compare anthropometric outcomes among community and clinic recruited infants, adjusting for age at enrollment, gender, and season. Among 32,877 infants enrolled in the trial, 21,273 (64.7%) were recruited via community outreach. Mean weight-for-age z-score (WAZ) was -0.60 ± 1.2 (SD), weight-for-length z-score (WLZ) was -0.16 ± 1.5, and length-for-age z-score was-0.53 ± 1.3. Infants enrolled in the community had lower WAZ (mean difference, -0.12; 95% CI, -0.20 to -0.04) and WLZ (mean difference, -0.21; 95% CI, -0.32 to -0.09). Community-recruited infants were more often underweight (WAZ < -2; odds ratio [OR], 1.25; 95% CI, 1.09-1.43) and wasted (WLZ < -2; OR, 1.54; 95% CI, 1.31-1.79). There was no evidence of a difference in height-based measures. Community and clinic recruitment likely reach different populations of children.

Rates of SARS-CoV-2 transmission between and into California state prisons.

Correctional institutions are a crucial hotspot amplifying SARS-CoV-2 spread and disease disparity in the U.S. In the California state prison system, multiple massive outbreaks have been caused by transmission between prisons. Correctional staff are a likely vector for transmission into the prison system from surrounding communities. We used publicly available data to estimate the magnitude of flows to and between California state prisons, estimating rates of transmission from communities to prison staff and residents, among and between residents and staff within facilities, and between staff and residents of distinct facilities in the state's 34 prisons through March 22, 2021. We use a mechanistic model, the Hawkes process, reflecting the dynamics of SARS-CoV-2 transmission, for joint estimation of transmission rates. Using nested models for hypothesis testing, we compared the results to simplified models (i) without transmission between prisons, and (ii) with no distinction between prison staff and residents. We estimated that transmission between different facilities' staff is a significant cause of disease spread, and that staff are a vector of transmission between resident populations and outside communities. While increased screening and vaccination of correctional staff may help reduce introductions, large-scale decarceration remains crucially needed as more limited measures are not likely to prevent large-scale disease spread.

GO-Tibia: a masked, randomized control trial evaluating gentamicin versus saline in open tibia fractures.

BACKGROUND: The rate of open tibia fractures is rapidly increasing across the globe due to a recent rise in road traffic accidents, predominantly in low- and low-middle-income countries. These injuries are orthopedic emergencies associated with infection rates as high as 40% despite the use of systemic antibiotics and surgical debridement. The use of local antibiotics has shown some promise in reducing the burden of infection in these injuries due to increasing local tissue availability; however, no trial has yet been appropriately powered to evaluate for definitive evidence and the majority of current studies have taken place in a high-resource countries where resources and the bio-burden may be different. METHODS: This is a prospective randomized, masked, placebo-controlled superiority trial designed to evaluate the efficacy of locally administered gentamicin versus placebo in the prevention of fracture-related infection in adults (age > 18 years) with primarily closeable Gustillo-Anderson class I, II, and IIIA open tibia fractures. Eight hundred ninety patients will be randomized to receive an injection of either gentamicin (treatment group) or saline (control group) at the site of their primarily closed open fracture. The primary outcome will be the occurrence of a fracture-related infection occurring during the course of the 12-month follow-up. DISCUSSION: This study will definitively assess the effectiveness of local gentamicin for the prevention of fracture-related infections in adults with open tibia fractures in Tanzania. The results of this study have the potential to demonstrate a low-cost, widely available intervention for the reduction of infection in open tibia fractures. TRIAL REGISTRATION: Clinicaltrials.gov NCT05157126. Registered on December 14, 2021.

A complex systems model of breast cancer etiology: The Paradigm II Model.

BACKGROUND: Complex systems models of breast cancer have previously focused on prediction of prognosis and clinical events for individual women. There is a need for understanding breast cancer at the population level for public health decision-making, for identifying gaps in epidemiologic knowledge and for the education of the public as to the complexity of this most common of cancers. METHODS AND FINDINGS: We developed an agent-based model of breast cancer for the women of the state of California using data from the U.S. Census, the California Health Interview Survey, the California Cancer Registry, the National Health and Nutrition Examination Survey and the literature. The model was implemented in the Julia programming language and R computing environment. The Paradigm II model development followed a transdisciplinary process with expertise from multiple relevant disciplinary experts from genetics to epidemiology and sociology with the goal of exploring both upstream determinants at the population level and pathophysiologic etiologic factors at the biologic level. The resulting model reproduces in a reasonable manner the overall age-specific incidence curve for the years 2008-2012 and incidence and relative risks due to specific risk factors such as BRCA1, polygenic risk, alcohol consumption, hormone therapy, breastfeeding, oral contraceptive use and scenarios for environmental toxin exposures. CONCLUSIONS: The Paradigm II model illustrates the role of multiple etiologic factors in breast cancer from domains of biology, behavior and the environment. The value of the model is in providing a virtual laboratory to evaluate a wide range of potential interventions into the social, environmental and behavioral determinants of breast cancer at the population level.

Targeted Mass Azithromycin Distribution for Trachoma: A Community-Randomized Trial (TANA II).

BACKGROUND: Current guidelines recommend annual community-wide mass administration of azithromycin for trachoma. Targeting treatments to those most likely to be infected could reduce the amount of unnecessary antibiotics distributed. METHODS: In a cluster-randomized trial conducted from 1 November 2010 through 8 November 2013, 48 Ethiopian communities previously treated with annual mass azithromycin distributions for trachoma were randomized in equal numbers to (1) annual azithromycin distributions targeted to children aged 0-5 years, (2) annual azithromycin distributions targeted to households with a child aged 0-5 years found to have clinically active trachoma, (3) continued annual mass azithromycin distributions to the entire community, or (4) cessation of treatment. The primary outcome was the community prevalence of ocular chlamydia infection among children aged 0-9 years at month 36. Laboratory personnel were masked to treatment allocation. RESULTS: The prevalence of ocular chlamydia infection among children aged 0-9 years increased from 4.3% (95% confidence interval [CI], .9%-8.6%) at baseline to 8.7% (95% CI, 4.2%-13.9%) at month 36 in the age-targeted arm, and from 2.8% (95% CI, .8%-5.3%) at baseline to 6.3% (95% CI, 2.9%-10.6%) at month 36 in the household-targeted arm. After adjusting for baseline chlamydia prevalence, the 36-month prevalence of ocular chlamydia was 2.4 percentage points greater in the age-targeted group (95% CI, -4.8% to 9.6%; P = .50; prespecified primary analysis). No adverse events were reported. CONCLUSIONS: Targeting azithromycin treatment to preschool children was no different than targeting azithromycin to households with a child with clinically active trachoma. Neither approach reduced ocular chlamydia over the 3-year study. CLINICAL TRIALS REGISTRATION: NCT01202331.

Change in Cone Structure Over 24 Months in USH2A-Related Retinal Degeneration.

PURPOSE: To describe cone structure changes using adaptive optics scanning laser ophthalmoscopy (AOSLO) in the Rate of Progression of USH2A-related Retinal Degeneration (RUSH2A) study. DESIGN: Multicenter, longitudinal natural history study. METHODS: AOSLO images were acquired at 4 centers, twice at baseline and annually for 24 months in this natural history study. For each eye, at least 10 regions of interest (ROIs) with ≥50 contiguous cones were analyzed by masked, independent graders. Cone spacing Z-scores, standard deviations from the normal mean at the measured location, were compared between graders and tests at baseline. The association of cone spacing with clinical characteristics was assessed using linear mixed effects regression models weighted by image quality score. Annual rates of change were calculated based on differences between visits. RESULTS: Fourteen eyes of 14 participants were imaged, with 192 ROIs selected at baseline. There was variability among graders, which was greater in images with lower image quality score (P < .001). Cone spacing was significantly correlated with eccentricity, quality score, and disease duration (P < .02). On average, the cone spacing Z-score increased 0.14 annually (about 9%, P < .001). We observed no significant differences in rate of change between disease type (Usher syndrome or retinitis pigmentosa), imaging site, or grader. CONCLUSIONS: Using current methods, the analysis of quantitative measures of cone structure showed some challenges, yet showed promise that AOSLO images can be used to characterize progressive change over 24 months. Additional multicenter studies using AOSLO are needed to advance cone mosaic metrics as sensitive outcome measures for clinical trials. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.

Neonatal Azithromycin Administration and Growth during Infancy: A Randomized Controlled Trial.

Observational studies have linked early-life antibiotic exposure to increased risk of obesity in children in high income settings. We evaluated whether neonatal antibiotic exposure led to changes in infant growth at 6 months of age in Burkina Faso. Neonates aged 8 to 27 days of age who weighed at least 2,500 g at the time of enrollment were randomized in a 1:1 fashion to a single oral 20-mg/kg dose of azithromycin or equivalent volume of placebo from April 2019 through December 2020. Weight, length, and mid-upper-arm circumference (MUAC) were measured at baseline and 6 months of age. Growth outcomes, including weight gain in grams per day, length change in millimeters per day, and changes in weight-for-age Z-score (WAZ), weight-for-length Z-score (WLZ), length-for-age Z-score (LAZ), and MUAC were compared among neonates randomized to azithromycin compared with placebo. Among 21,832 neonates enrolled in the trial, median age at enrollment was 11 days, and 50% were female. We found no evidence of a difference in weight gain (mean difference -0.009 g/day, 95% confidence interval [CI]: -0.16 to 0.14, P = 0.90), length change (mean difference 0.003 mm/day, 95% CI: -0.002 to 0.007, P = 0.23), or WAZ (mean difference -0.005 SD, 95% CI: -0.03 to 0.02, P = 0.72), WLZ (mean difference -0.01 SD, 95% CI: -0.05 to 0.02, P = 0.39), LAZ (mean difference 0.01, 95% CI: -0.02 to 0.04, P = 0.47), or MUAC (mean difference 0.01 cm, 95% CI: -0.02 to 0.04, P = 0.49). These results do not suggest that azithromycin has growth-promoting properties in infants when administered during the neonatal period. Trial registration: ClinicalTrials.gov NCT03682653.

Association between Quality of Life and Visual Acuity in a Randomized Clinical Trial of Patients with Uveitis Taking Antimetabolites.

PURPOSE: To evaluate how changes in visual acuity are associated with changes in quality of life (QoL) among patients with non-infectious uveitis taking antimetabolites. METHODS: This secondary analysis of the multicenter First-line Antimetabolites as Steroid-sparing Treatment (FAST) Uveitis Trial involves 216 participants randomized to methotrexate or mycophenolate mofetil. Vision-related (NEI-VFQ and IND-VFQ) and health-related (PCS and MCS SF-36v2) QoL and visual acuity were measured at baseline and 6-month primary endpoint. RESULTS: Visual acuity was significantly associated and correlated with all QoL measures (Spearman correlation coefficients = 0.5, 0.5, 0.3, and 0.4 for NEI-VFQ, IND-VFQ, SF-36v2 MCS and PCS, respectively). All observed changes in QoL met or exceeded the minimal clinically important difference definition on each scale. Treatment group was not significantly associated with any QoL measure. CONCLUSION: By adding insight beyond visual acuity, QoL provides a more comprehensive picture of the patient experience during uveitis treatment.Abbreviations and Acronyms: QoL = quality of life; VR-QoL = vision-related quality of life; HR-QoL = health-related quality of life; FAST = First-line Antimetabolites as Corticosteroid Sparing Treatment; NEI-VFQ = National Eye Institute Visual Functioning Questionnaire; IND-VFQ = Indian Visual Functioning Questionnaire; SF-36v2 = Medical Outcomes Study 36-Item Short Form Survey; PCS = physical component score; MCS = mental component score; 95% CI = 95% confidence interval; MCID = minimal clinically important difference.

Cone Structure and Function in RPGR- and USH2A-Associated Retinal Degeneration.

PURPOSE: To compare cone structure and function between RPGR- and USH2A-associated retinal degeneration. DESIGN: Retrospective, observational, cross-sectional study. METHODS: This multicenter study included 13 eyes (9 participants) with RPGR-related X-linked retinitis pigmentosa (RPGR), 15 eyes (10 participants) with USH2A-related Usher syndrome type 2 (USH2), 16 eyes (9 participants) with USH2A-related autosomal recessive retinitis pigmentosa (ARRP), and 7 normal eyes (6 participants). Structural measures included cone spacing and density from adaptive optics scanning laser ophthalmoscopy and photoreceptor inner segment (IS), outer segment (OS), and outer nuclear layer (ONL) thickness from optical coherence tomography (OCT) images. OCT angiography images were used to study choriocapillaris flow deficit percent (CCFD). Cone function was assessed by fundus-guided microperimetry. Measures were compared at designated regions using analysis of variance with pairwise comparisons among disease groups, adjusted for disease duration and eccentricity. RESULTS: OCT segmentation revealed shorter OS and IS, with reduced ONL thickness in RPGR compared to normal (OS: P < .001, IS: P = .001, ONL: P = .005), USH2 (OS: P = .01, IS: P = .03, ONL: P = .03), or ARRP (OS: P = .001, ONL: P = .03). Increased cone spacing was observed in both RPGR (P = .03) and USH2 compared with normal (P = .048). The mean CCFD in RPGR was greater than in USH2 (P = .02). Microperimetry demonstrated below-normal regional sensitivity in RPGR (P = .004), USH2 (P = .02), and ARRP (P = .009), without significant intergroup differences. CONCLUSIONS: Outer retinal structure and choriocapillaris perfusion were more abnormal in RPGR- than USH2A-related retinal degenerations, whereas there were no significant differences in below-normal regional sensitivity between each rod-cone degeneration associated with variants in these 2 genes expressed at the photoreceptor-connecting cilium.

Identifying Paucisymptomatic or Asymptomatic and Unrecognized Ebola Virus Disease Among Close Contacts Based on Exposure Risk Assessments and Screening Algorithms.

BACKGROUND: There is limited evidence to evaluate screening algorithms with rapid antigen testing and exposure assessments as identification strategies for paucisymptomatic or asymptomatic Ebola virus (EBOV) infection and unrecognized EBOV disease (EVD). METHODS: We used serostatus and self-reported postexposure symptoms from a cohort study to classify contact-participants as having no infection, paucisymptomatic or asymptomatic infection, or unrecognized EVD. Exposure risk was categorized as low, intermediate, or high. We created hypothetical scenarios to evaluate the World Health Organization (WHO) case definition with or without rapid diagnostic testing (RDT) or exposure assessments. RESULTS: This analysis included 990 EVD survivors and 1909 contacts, of whom 115 (6%) had paucisymptomatic or asymptomatic EBOV infection, 107 (6%) had unrecognized EVD, and 1687 (88%) were uninfected. High-risk exposures were drivers of unrecognized EVD (adjusted odds ratio, 3.5 [95% confidence interval, 2.4-4.9]). To identify contacts with unrecognized EVD who test negative by the WHO case definition, the sensitivity was 96% with RDT (95% confidence interval, 91%-99%), 87% with high-risk exposure (82%-92%), and 97% with intermediate- to high-risk exposures (93%-99%). The proportion of false-positives was 2% with RDT and 53%-93% with intermediate- and/or high-risk exposures. CONCLUSION: We demonstrated the utility and trade-offs of sequential screening algorithms with RDT or exposure risk assessments as identification strategies for contacts with unrecognized EVD.

Risk factors for corneal ulcers: a population-based matched case-control study in Nepal.

BACKGROUND/AIMS: We aimed to examine risk factors for corneal ulcer in a rural and peri-urban setting in Nepal. METHODS: This population-based matched case-control study was nested in a cluster randomised trial in 24 village development committees in Nepal. Incidence density sampling was used to match incident corneal opacity cases to controls, matching on time of opacity, age, sex and location. Cases and controls were invited to participate in a survey of risk factors for corneal ulcer. Risk factors were evaluated using conditional logistic regression to account for matching. RESULTS: Of the 540 participants with incident opacities identified in the trial, 433 were willing to participate in this substudy and matched to a control. Compared with controls, cases had lower odds of having any education vs no education (adjusted OR, aOR 0.60, 95% CI 0.39 to 0.94), working in non-manual labour occupations vs manual labour occupations (aOR 0.64, 95% CI 0.42 to 0.95) and preferring medical shops for ocular trauma versus eye care system centres (aOR 0.58, 95% CI 0.37 to 0.92). Cases had higher odds of protective goggle use versus no protection (aOR 3.8, 95% CI 1.3 to 11.0) and having an ocular injury vs none (aOR 7.7, 95% CI 4.3 to 13.6) compared with controls. CONCLUSION: We found ocular injury, manual labour and lower education to be strongly associated with the development of corneal ulcer. Given the persistent burden of corneal blindness in this area, prevention efforts could target efforts to increase access to care in areas where these factors are common.

Social Network Analysis of Ebola Virus Disease During the 2014 Outbreak in Sukudu, Sierra Leone.

Background: Transmission by unreported cases has been proposed as a reason for the 2013-2016 Ebola virus (EBOV) epidemic decline in West Africa, but studies that test this hypothesis are lacking. We examined a transmission chain within social networks in Sukudu village to assess spread and transmission burnout. Methods: Network data were collected in 2 phases: (1) serological and contact information from Ebola cases (n = 48, including unreported); and (2) interviews (n = 148), including Ebola survivors (n = 13), to identify key social interactions. Social links to the transmission chain were used to calculate cumulative incidence proportion as the number of EBOV-infected people in the network divided by total network size. Results: The sample included 148 participants and 1522 contacts, comprising 10 social networks: 3 had strong links (>50% of cases) to the transmission chain: household sharing (largely kinship), leisure time, and talking about important things (both largely non-kin). Overall cumulative incidence for these networks was 37 of 311 (12%). Unreported cases did not have higher network centrality than reported cases. Conclusions: Although this study did not find evidence that explained epidemic decline in Sukudu, it excluded potential reasons (eg, unreported cases, herd immunity) and identified 3 social interactions in EBOV transmission.

Effect of Biannual Mass Azithromycin Distributions to Preschool-Aged Children on Trachoma Prevalence in Niger: A Cluster Randomized Clinical Trial.

Importance: Because transmission of ocular strains of Chlamydia trachomatis is greatest among preschool-aged children, limiting azithromycin distributions to this age group may conserve resources and result in less antimicrobial resistance, which is a potential advantage in areas with hypoendemic trachoma and limited resources. Objective: To determine the efficacy of mass azithromycin distributions to preschool-aged children as a strategy for trachoma elimination in areas with hypoendemic disease. Design, Setting, and Participants: In this cluster randomized clinical trial performed from November 23, 2014, until July 31, 2017, thirty rural communities in Niger were randomized at a 1:1 ratio to biannual mass distributions of either azithromycin or placebo to children aged 1 to 59 months. Participants and study personnel were masked to treatment allocation. Data analyses for trachoma outcomes were performed from October 19, 2021, through June 10, 2022. Interventions: Every 6 months, a single dose of either oral azithromycin (20 mg/kg using height-based approximation for children who could stand or weight calculation for small children) or oral placebo was provided to all children aged 1 to 59 months. Main Outcomes and Measures: Trachoma was a prespecified outcome of the trial, assessed as the community-level prevalence of trachomatous inflammation-follicular and trachomatous inflammation-intense through masked grading of conjunctival photographs from a random sample of 40 children per community each year during the 2-year study period. A secondary outcome was the seroprevalence of antibodies to C trachomatis antigens. Results: At baseline, 4726 children in 30 communities were included; 1695 children were enrolled in 15 azithromycin communities and 3031 children were enrolled in 15 placebo communities (mean [SD] proportions of boys, 51.8% [4.7%] vs 52.0% [4.2%]; mean [SD] age, 30.8 [2.8] vs 30.6 [2.6] months). The mean coverage of study drug for the 4 treatments was 79% (95% CI, 75%-83%) in the azithromycin group and 82% (95% CI, 79%-85%) in the placebo group. The mean prevalence of trachomatous inflammation-follicular at baseline was 1.9% (95% CI, 0.5%-3.5%) in the azithromycin group and 0.9% (95% CI, 0-1.9%) in the placebo group. At 24 months, trachomatous inflammation-follicular prevalence was 0.2% (95% CI, 0-0.5%) in the azithromycin group and 0.8% (95% CI, 0.2%-1.6%) in the placebo group (incidence rate ratio adjusted for baseline: 0.18 [95% CI, 0.01-1.20]; permutation P = .07). Conclusions and Relevance: The findings of this trial do not show that biannual mass azithromycin distributions to preschool-aged children were more effective than placebo, although the underlying prevalence of trachoma was low. The sustained absence of trachoma even in the placebo group suggests that trachoma may have been eliminated as a public health problem in this part of Niger. Trial Registration: ClinicalTrials.gov Identifier: NCT02048007.