Evolution of HIV-1 envelope towards reduced neutralization sensitivity, as demonstrated by contemporary HIV-1 subtype B from the United States.

Subtype B HIV-1 has been the primary driver of the HIV-1 epidemic in the United States (U.S.) for over forty years and is also a prominent subtype in the Americas, Europe, Australia, the Middle East and North Africa. In this study, the neutralization profiles of contemporary subtype B Envs from the U.S. were assessed to characterize changes in neutralization sensitivities over time. We generated a panel of 30 contemporary pseudoviruses (PSVs) and demonstrated continued diversification of subtype B Env from the 1980s up to 2018. Neutralization sensitivities of the contemporary subtype B PSVs were characterized using 31 neutralizing antibodies (NAbs) and were compared with strains from earlier in the HIV-1 pandemic. A significant reduction in Env neutralization sensitivity was observed for 27 out of 31 NAbs for the contemporary as compared to earlier-decade subtype B PSVs. A decline in neutralization sensitivity was observed across all Env domains; the NAbs that were most potent early in the pandemic suffered the greatest decline in potency over time. A meta-analysis demonstrated this trend across multiple subtypes. As HIV-1 Env diversification continues, changes in Env antigenicity and neutralization sensitivity should continue to be evaluated to inform the development of improved vaccine and antibody products to prevent and treat HIV-1.

Precision symptom phenotyping identifies early clinical and proteomic predictors of distinct COVID-19 sequelae.

BACKGROUND: Post-COVID conditions (PCC) are difficult to characterize, diagnose, predict, and treat due to overlapping symptoms and poorly understood pathology. Identifying inflammatory profiles may improve clinical prognostication and trial endpoints. METHODS: 1,988 SARS-CoV-2 positive U.S. Military Health System beneficiaries with quantitative post-COVID symptom scores were included in this analysis. Among participants who reported moderate-to-severe symptoms on surveys collected 6-months post-SARS-CoV-2 infection, principal component analysis (PCA) followed by K-means clustering identified distinct clusters of symptoms. RESULTS: Three symptom-based clusters were identified: a sensory cluster (loss of smell and/or taste), a fatigue/difficulty thinking cluster, and a difficulty breathing/exercise intolerance cluster. Individuals within the sensory cluster were all outpatients during their initial COVID-19 presentation. The difficulty breathing cluster had a higher likelihood of obesity and COVID-19 hospitalization compared to those with no/mild symptoms at 6-months post-infection. Multinomial regression linked early post-infection D-dimer and IL-1RA elevation to fatigue/difficulty thinking, and elevated ICAM-1 concentrations to sensory symptoms. CONCLUSIONS: We identified three distinct symptom-based PCC phenotypes with specific clinical risk factors and early post-infection inflammatory predictors. With further validation and characterization, this framework may allow more precise classification of PCC cases and potentially improve the diagnosis, prognostication, and treatment of PCC.

Understanding "Hybrid Immunity": Comparison and Predictors of Humoral Immune Responses to Severe Acute Respiratory Syndrome Coronavirus 2 Infection (SARS-CoV-2) and Coronavirus Disease 2019 (COVID-19) Vaccines.

BACKGROUND: Comparison of humoral responses in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccinees, those with SARS-CoV-2 infection, or combinations of vaccine/ infection ("hybrid immunity") may clarify predictors of vaccine immunogenicity. METHODS: We studied 2660 US Military Health System beneficiaries with a history of SARS-CoV-2 infection-alone (n = 705), vaccination-alone (n = 932), vaccine-after-infection (n = 869), and vaccine-breakthrough-infection (n = 154). Peak anti-spike-immunoglobulin G (IgG) responses through 183 days were compared, with adjustment for vaccine product, demography, and comorbidities. We excluded those with evidence of clinical or subclinical SARS-CoV-2 reinfection from all groups. RESULTS: Multivariable regression results indicated that vaccine-after-infection anti-spike-IgG responses were higher than infection-alone (P < .01), regardless of prior infection severity. An increased time between infection and vaccination was associated with greater post-vaccination IgG response (P < .01). Vaccination-alone elicited a greater IgG response but more rapid waning of IgG (P < .01) compared with infection-alone (P < .01). BNT162b2 and mRNA-1273 vaccine-receipt was associated with greater IgG responses compared with JNJ-78436735 vaccine-receipt (P < .01), regardless of infection history. Those with vaccine-after-infection or vaccine-breakthrough-infection had a more durable anti-spike-IgG response compared to infection-alone (P < .01). CONCLUSIONS: Vaccine-receipt elicited higher anti-spike-IgG responses than infection-alone, although IgG levels waned faster in those vaccinated (compared to infection-alone). Vaccine-after-infection elicits a greater humoral response compared with vaccine or infection alone; and the timing, but not disease severity, of prior infection predicted these post-vaccination IgG responses. While differences between groups were small in magnitude, these results offer insights into vaccine immunogenicity variations that may help inform vaccination timing strategies.

Temporal Improvements in COVID-19 Outcomes for Hospitalized Adults: A Post Hoc Observational Study of Remdesivir Group Participants in the Adaptive COVID-19 Treatment Trial.

BACKGROUND: The COVID-19 standard of care (SOC) evolved rapidly during 2020 and 2021, but its cumulative effect over time is unclear. OBJECTIVE: To evaluate whether recovery and mortality improved as SOC evolved, using data from ACTT (Adaptive COVID-19 Treatment Trial). DESIGN: ACTT is a series of phase 3, randomized, double-blind, placebo-controlled trials that evaluated COVID-19 therapeutics from February 2020 through May 2021. ACTT-1 compared remdesivir plus SOC to placebo plus SOC, and in ACTT-2 and ACTT-3, remdesivir plus SOC was the control group. This post hoc analysis compared recovery and mortality between these comparable sequential cohorts of patients who received remdesivir plus SOC, adjusting for baseline characteristics with propensity score weighting. The analysis was repeated for participants in ACTT-3 and ACTT-4 who received remdesivir plus dexamethasone plus SOC. Trends in SOC that could explain outcome improvements were analyzed. (ClinicalTrials.gov: NCT04280705 [ACTT-1], NCT04401579 [ACTT-2], NCT04492475 [ACTT-3], and NCT04640168 [ACTT-4]). SETTING: 94 hospitals in 10 countries (86% U.S. participants). PARTICIPANTS: Adults hospitalized with COVID-19. INTERVENTION: SOC. MEASUREMENTS: 28-day mortality and recovery. RESULTS: Although outcomes were better in ACTT-2 than in ACTT-1, adjusted hazard ratios (HRs) were close to 1 (HR for recovery, 1.04 [95% CI, 0.92 to 1.17]; HR for mortality, 0.90 [CI, 0.56 to 1.40]). Comparable patients were less likely to be intubated in ACTT-2 than in ACTT-1 (odds ratio, 0.75 [CI, 0.53 to 0.97]), and hydroxychloroquine use decreased. Outcomes improved from ACTT-2 to ACTT-3 (HR for recovery, 1.43 [CI, 1.24 to 1.64]; HR for mortality, 0.45 [CI, 0.21 to 0.97]). Potential explanatory factors (SOC trends, case surges, and variant trends) were similar between ACTT-2 and ACTT-3, except for increased dexamethasone use (11% to 77%). Outcomes were similar in ACTT-3 and ACTT-4. Antibiotic use decreased gradually across all stages. LIMITATION: Unmeasured confounding. CONCLUSION: Changes in patient composition explained improved outcomes from ACTT-1 to ACTT-2 but not from ACTT-2 to ACTT-3, suggesting improved SOC. These results support excluding nonconcurrent controls from analysis of platform trials in rapidly changing therapeutic areas. PRIMARY FUNDING SOURCE: National Institute of Allergy and Infectious Diseases.

The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) mRNA Vaccine-Breakthrough Infection Phenotype Includes Significant Symptoms, Live Virus Shedding, and Viral Genetic Diversity.

Little is known about severe acute respiratory syndrome coronavirus 2 "vaccine-breakthrough" infections (VBIs). Here we characterize 24 VBIs in predominantly young healthy persons. While none required hospitalization, a proportion endorsed severe symptoms and shed live virus as high as 4.13 × 103 plaque-forming units/mL. Infecting genotypes included both variant-of-concern (VOC) and non-VOC strains.

Clinical, Immunological, and Virological SARS-CoV-2 Phenotypes in Obese and Nonobese Military Health System Beneficiaries.

BACKGROUND: The mechanisms underlying the association between obesity and coronavirus disease 2019 (COVID-19) severity remain unclear. After verifying that obesity was a correlate of severe COVID-19 in US Military Health System (MHS) beneficiaries, we compared immunological and virological phenotypes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in both obese and nonobese participants. METHODS: COVID-19-infected MHS beneficiaries were enrolled, and anthropometric, clinical, and demographic data were collected. We compared the SARS-CoV-2 peak IgG humoral response and reverse-transcription polymerase chain reaction viral load in obese and nonobese patients, stratified by hospitalization, utilizing logistic regression models. RESULTS: Data from 511 COVID-19 patients were analyzed, among whom 24% were obese and 14% severely obese. Obesity was independently associated with hospitalization (adjusted odds ratio [aOR], 1.91; 95% confidence interval [CI], 1.15-3.18) and need for oxygen therapy (aOR, 3.39; 95% CI, 1.61-7.11). In outpatients, severely obese had a log10 (1.89) higher nucleocapsid (N1) genome equivalents (GE)/reaction and log10 (2.62) higher N2 GE/reaction than nonobese (P = 0.03 and P < .001, respectively). We noted a correlation between body mass index and peak anti-spike protein IgG in inpatients and outpatients (coefficient = 5.48, P < .001). CONCLUSIONS: Obesity is a strong correlate of COVID-19 severity in MHS beneficiaries. These findings offer new pathophysiological insights into the relationship between obesity and COVID-19 severity.

Comparison of A(H3N2) Neutralizing Antibody Responses Elicited by 2018-2019 Season Quadrivalent Influenza Vaccines Derived from Eggs, Cells, and Recombinant Hemagglutinin.

BACKGROUND: Low vaccine effectiveness against A(H3N2) influenza in seasons with little antigenic drift has been attributed to substitutions in hemagglutinin (HA) acquired during vaccine virus propagation in eggs. Clinical trials comparing recombinant HA vaccine (rHA) and cell-derived inactivated influenza vaccine (IIV) to egg-derived IIVs provide opportunities to assess how egg-adaptive substitutions influence HA immunogenicity. METHODS: Neutralization titers in pre- and postimmunization sera from 133 adults immunized with 1 of 3 types of influenza vaccines in a randomized, open-label trial during the 2018-2019 influenza season were measured against egg- and cell-derived A/Singapore/INFIMH-16-0019/2016-like and circulating A(H3N2) influenza viruses using HA pseudoviruses. RESULTS: All vaccines elicited neutralizing antibodies to all H3 vaccine antigens, but the rHA vaccine elicited the highest titers and seroconversion rates against all strains tested. Egg- and cell-derived IIVs elicited responses similar to each other. Preimmunization titers against H3 HA pseudoviruses containing egg-adaptive substitutions T160K and L194P were high, but lower against H3 HA pseudoviruses without those substitutions. All vaccines boosted neutralization titers against HA pseudoviruses with egg-adaptive substitutions, but poorly neutralized wild-type 2019-2020 A/Kansas/14/2017 (H3N2) HA pseudoviruses. CONCLUSION: Egg- and cell-derived 2018-2019 season influenza vaccines elicited similar neutralization titers and response rates, indicating that the cell-derived vaccine did not improve immunogenicity against the A(H3N2) viruses. The higher responses after rHA vaccination may be due to its higher HA content. All vaccines boosted titers to HA with egg-adaptive substitutions, suggesting boosting from past antigens or better exposure of HA epitopes. Studies comparing immunogenicity and effectiveness of different influenza vaccines across many seasons are needed.

Association between depression and HIV treatment outcomes in a US military population with HIV infection.

BACKGROUND: Depression is common among HIV-infected individuals and may contribute to suboptimal adherence to antiretroviral therapy (ART) and subsequent inability to attain viral load (VL) suppression. We evaluated associations between depression, self-reported adherence, and longitudinal HIV treatment outcomes in US Military HIV Natural History Study (NHS) participants with and without depression. METHODS: Male NHS participants with available ICD-9 data for mental health diagnoses, Center for Epidemiological Studies Depression (CES-D) measures, and self-reported adherence (SRA) were included. ART use was defined as ART initiation between 2006 and 2010, with follow-up through 2015. SRA was defined as taking 95% of ART doses and continuous ART was defined as longitudinal ART use with gaps < 30 days. Continuous VL suppression was defined as maintaining VLs < 200 c/mL on ART. To analyse the association between depression and HIV treatment outcomes, latent class analysis was used to create classes of depression trajectories: low depression (LD), recent onset depression (ROD) and high Depression (HD). RESULTS: Participants had a mean age of 32 (± 8.3) years at HIV diagnosis, and similar proportions were Caucasian (44.3%) or African American (40.8%). Overall, older participants at HIV diagnosis had greater odds of having 95% self-reported adherence (OR 1.06, 95% CI 1.02-1.12), and African Americans had lower odds (OR 0.41, 95% CI 0.22-0.76) compared to Caucasians (OR 1.49, 95% CI 0.52-4.28). However, there was no difference in SRA by depression trajectory. Participants with HD had an increased odds of taking ART continuously (OR 1.75, 95% CI 0.99-3.09), and those with ROD had significantly higher odds of virologic failure (OR 0.58, 95% CI 0.38-0.91). CONCLUSIONS: Although there was no observed association between depression and SRA, participants with ROD had lower odds of attaining the HIV treatment goal of VL suppression. Continued efforts to identify and aggressively manage mental health disorders is important to success along the HIV care continuum.

Persistent Low-level Viremia While on Antiretroviral Therapy Is an Independent Risk Factor for Virologic Failure.

BACKGROUND: Whether persistent low-level viremia (pLLV) predicts virologic failure (VF) is unclear. We used data from the US Military HIV Natural History Study (NHS), to examine the association of pLLV and VF. METHODS: NHS subjects who initiated combination antiretroviral therapy (ART) after 1996 were included if they had 2 or more VLs measured with a lower limit of detection of ≤50 copies/mL. VF was defined as a confirmed VL ≥200 copies/mL or any VL >1000 copies/mL. Participants were categorized into mutually exclusive virologic categories: intermittent LLV (iLLV) (VL of 50-199 copies/mL on <25% of measurements), pLLV (VL of 50-199 copies/mL on ≥25% of measurements), high-level viremia (hLV) (VL of 200-1000 copies/mL), and continuous suppression (all VL <50 copies/mL). Cox proportional hazards models were used to evaluate the association between VF and LLV; hazard ratios and 95% confidence interval (CI) are presented. RESULTS: Two thousand six subjects (median age 29.2 years, 93% male, 41% black) were included; 383 subjects (19%) experienced VF. After adjusting for demographics, VL, CD4 counts, ART regimen, prior use of mono or dual antiretrovirals, and time to ART start, pLLV (3.46 [2.42-4.93]), and hLV (2.29 [1.78-2.96]) were associated with VF. Other factors associated with VF include black ethnicity (1.33 [1.06-1.68]) and antiretroviral use prior to ART (1.79 [1.34-2.38]). Older age at ART initiation (0.71 [0.61-0.82]) and non-nucleoside reverse transcriptase inhibitor (0.68 [0.51-0.90]) or integrase strand transfer inhibitor use (0.26 [0.13-0.53]) were protective. CONCLUSION: Our data add to the body of evidence that suggests persistent LLV is associated with deleterious virologic consequences.

Reliability, Validity, and Responsiveness of InFLUenza Patient-Reported Outcome (FLU-PRO©) Scores in Influenza-Positive Patients.

OBJECTIVES: To assess the reliability, validity, and responsiveness of InFLUenza Patient-Reported Outcome (FLU-PRO©) scores for quantifying the presence and severity of influenza symptoms. METHODS: An observational prospective cohort study of adults (≥18 years) with influenza-like illness in the United States, the United Kingdom, Mexico, and South America was conducted. Participants completed the 37-item draft FLU-PRO daily for up to 14 days. Item-level and factor analyses were used to remove items and determine factor structure. Reliability of the final tool was estimated using Cronbach α and intraclass correlation coefficients (2-day reliability). Convergent and known-groups validity and responsiveness were assessed using global assessments of influenza severity and return to usual health. RESULTS: Of the 536 patients enrolled, 221 influenza-positive subjects comprised the analytical sample. The mean age of the patients was 40.7 years, 60.2% were women, and 59.7% were white. The final 32-item measure has six factors/domains (nose, throat, eyes, chest/respiratory, gastrointestinal, and body/systemic), with a higher order factor representing symptom severity overall (comparative fit index = 0.92; root mean square error of approximation = 0.06). Cronbach α was high (total = 0.92; domain range = 0.71-0.87); test-retest reliability (intraclass correlation coefficient, day 1-day 2) was 0.83 for total scores and 0.57 to 0.79 for domains. Day 1 FLU-PRO domain and total scores were moderately to highly correlated (≥0.30) with Patient Global Rating of Flu Severity (except nose and throat). Consistent with known-groups validity, scores differentiated severity groups on the basis of global rating (total: F = 57.2, P < 0.001; domains: F = 8.9-67.5, P < 0.001). Subjects reporting return to usual health showed significantly greater (P < 0.05) FLU-PRO score improvement by day 7 than did those who did not, suggesting score responsiveness. CONCLUSIONS: Results suggest that FLU-PRO scores are reliable, valid, and responsive to change in influenza-positive adults.

Trial Evaluating Ambulatory Therapy of Travelers' Diarrhea (TrEAT TD) Study: A Randomized Controlled Trial Comparing 3 Single-Dose Antibiotic Regimens With Loperamide.

BACKGROUND: Recommended treatment for travelers' diarrhea includes the combination of an antibiotic, usually a fluoroquinolone or azithromycin, and loperamide for rapid resolution of symptoms. However, adverse events, postdose nausea with high-dose azithromycin, effectiveness of single-dose rifaximin, and emerging resistance to front-line agents are evidence gaps underlying current recommendations. METHODS: A randomized, double-blind trial was conducted in 4 countries (Afghanistan, Djibouti, Kenya, and Honduras) between September 2012 and July 2015. US and UK service members with acute watery diarrhea were randomized and received single-dose azithromycin (500 mg; 106 persons), levofloxacin (500 mg; 111 persons), or rifaximin (1650 mg; 107 persons), in combination with loperamide (labeled dosing). The efficacy outcomes included clinical cure at 24 hours and time to last unformed stool. RESULTS: Clinical cure at 24 hours occurred in 81.4%, 78.3%, and 74.8% of the levofloxacin, azithromycin, and rifaximin arms, respectively. Compared with levofloxacin, azithromycin was not inferior (P = .01). Noninferiority could not be shown with rifaximin (P = .07). At 48 and 72 hours, efficacy among regimens was equivalent (approximately 91% at 48 and 96% at 72 hours). The median time to last unformed stool did not differ between treatment arms (azithromycin, 3.8 hours; levofloxacin, 6.4 hours; rifaximin, 5.6 hours). Treatment failures were uncommon (3.8%, 4.4%, and 1.9% in azithromycin, levofloxacin, and rifaximin arms, respectively) (P = .55). There were no differences between treatment arms with postdose nausea, vomiting, or other adverse events. CONCLUSIONS: Single-dose azithromycin, levofloxacin, and rifaximin with loperamide were comparable for treatment of acute watery diarrhea. CLINICAL TRIAL REGISTRATION: NCT01618591.

Characterizing the Association Between Alcohol and HIV Virologic Failure in a Military Cohort on Antiretroviral Therapy.

BACKGROUND: The effects of at-risk drinking on HIV infection remain controversial. We investigated the impact of self-reported alcohol consumption on surrogate markers of HIV progression among individuals initiated on highly active antiretroviral therapy (HAART). METHODS: We analyzed individuals who were surveyed on alcohol use within a year of HAART initiation between 2006 and 2014. At-risk drinking was defined as consumption of at least 3 or 4 drinks/d, or 7 and 14 drinks/wk among women and men, respectively. We performed time-updated generalized estimating equation logistic regression to determine the effect of at-risk drinking on virologic failure (VF) and mixed-effects linear regression on CD4 count reconstitution, controlling for potential confounders. RESULTS: Of 801 individuals initiated on HAART, 752 individuals with alcohol survey data were included in the analysis. Of these, 45% (n = 336) met criteria for at-risk drinking at HAART initiation on at least 1 survey. The rates of VF were 4.30 per 100 person-years (95% CI [2.86, 6.21]) for at-risk drinkers and 2.45 per 100 person-years (95% CI [1.57, 3.65]) for individuals without at-risk drinking. At-risk drinking was not significantly associated with VF (OR 1.73, 95% CI [0.92, 3.25]) (p = 0.087) or CD4 reconstitution (CD4 increase 11.4; 95% CI [-19.8, 42.7]) in univariate analyses; however, in our multivariate model, a statistically significant relationship between VF and at-risk drinking was observed (OR 2.28, 95% CI [ 1.01, 5.15]). CONCLUSIONS: We found a high proportion of at-risk drinking in our military cohort, which was predictive of VF in multivariate analysis. Given alcohol's effect on myriad HIV and non-HIV outcomes, interventions to decrease the prevalence of at-risk drinking among HIV-infected individuals are warranted.

Factors associated with 10 years of continuous viral load suppression on HAART.

BACKGROUND: The principal goal of HAART is sustained viral load (VL) suppression resulting in immune reconstitution and improved HIV outcomes. We studied the factors associated with 10 years of continuous VL suppression on HAART in the US Military HIV Natural History Study. METHODS: Participants with continuous VL suppression (CS, n = 149) were compared to those who did not have continuous viral load suppression (NCS, n = 127) for ≥10 years on HAART. Factors associated with >10 years of VL suppression were evaluated by multivariate logistic regression. Additionally, association between CS and CD4 reconstitution was analyzed with a mixed effects model. RESULTS: Compared to NCS participants, a lower proportion of CS participants started HAART in the early HAART era (66 vs 90 %, for years 1996-1999; p < 0.001) and had less antiretroviral use prior to HAART (37 vs 83 %; p < 0.001). At initial HAART, the median CD4 cell count was higher and VL was lower for CS compared to NCS participants (375 cells/uL [256, 499] vs 261 cells/uL [146, 400]; p < 0.001 and 4.4 log10 copies/mL [3.5, 4.9] vs 4.5 log10 copies/mL [3.8, 5.0]; p = 0.048, respectively). New AIDS events were lower during HAART (5 vs 13 %; p = 0.032) and post-HAART CD4 trajectories were greater for the CS compared to NCS group. Factors negatively associated with ≥10 years of VL suppression included log10 VL at first HAART (OR 0.61, 95 % CI 0.4, 0.92; p = 0.020) and antiretroviral use prior to HAART (OR 0.16, 95 % CI 0.06, 0.38; p < .001). CONCLUSIONS: Sustained VL suppression is a key to long-term health in HIV-infected patients, as demonstrated by the lower proportion of AIDS events observed 10 years after HAART initiation. The current use of more potent and well-tolerated regimens may mitigate the negative factors of pre-HAART VL and prior ARV use encountered by treatment initiated in the early HAART era.

A single dose of benzathine penicillin G is as effective as multiple doses of benzathine penicillin G for the treatment of HIV-infected persons with early syphilis.

BACKGROUND: Treatment guidelines recommend the use of a single dose of benzathine penicillin G (BPG) for treating early syphilis in human immunodeficiency virus (HIV)-infected persons. However, data supporting this recommendation are limited. We examined the efficacy of single-dose BPG in the US Military HIV Natural History Study. METHODS: Subjects were included if they met serologic criteria for syphilis (ie, a positive nontreponemal test [NTr] confirmed by treponemal testing). Response to treatment was assessed at 13 months and was defined by a ≥4-fold decline in NTr titer. Multivariate Cox proportional hazard regression models were utilized to examine factors associated with treatment response. RESULTS: Three hundred fifty subjects (99% male) contributed 478 cases. Three hundred ninety-three cases were treated exclusively with BPG (141 with 1 dose of BPG). Treatment response was the same among those receiving 1 or >1 dose of BPG (92%). In a multivariate analysis, older age (hazard ratio [HR], 0.82 per 10-year increase; 95% confidence interval [CI], .73-.93) was associated with delayed response to treatment. Higher pretreatment titers (reference NTr titer <1:64; HR, 1.94 [95% CI, 1.58-2.39]) and CD4 counts (HR, 1.07 for every 100-cell increase [95% CI, 1.01-1.12]) were associated with a faster response to treatment. Response was not affected by the number of BPG doses received (reference, 1 dose of BPG; HR, 1.11 [95% CI, .89-1.4]). CONCLUSIONS: In this cohort, additional BPG doses did not affect treatment response. Our data support the current recommendations for the use of a single dose of BPG to treat HIV-infected persons with early syphilis.

Low Level Viremia Is Associated With Serious non-AIDS Events in People With HIV.

Background: The consequences of low-level viremia in people with HIV are unclear. We used data from the US Military HIV Natural History Study to examine the association of low-level viremia (LLV) and serious non-AIDS events (SNAEs). Methods: Included participants initiated antiretroviral therapy after 1996 and had ≥3 viral loads (VLs) measured, using an assay with a lower limit of detection of <50 copies/mL, ≥6 months after antiretroviral therapy initiation. VLs were categorized as lower levels of LLV (51-199 copies/mL), higher level of low-level viremia (HLLV; 200-999 copies/mL), and (VF; ≥200 copies/mL on 2 or more successive determinations or a single VL ≥1000 copies/mL), and virologic suppression (VS; ie, VL <50 copies/mL). Viral blips (ie, VLs between 50 and 999 copies/mL that are preceded and succeeded by VL <50 copies/mL) were analyzed in the VS category. Cox proportional hazards models were used to examine the association of LLV and SNAEs, adjusted hazard ratios and 95% confidence intervals are presented. Results: A total of 439 (17.4%) SNAEs were recorded among the 2528 participants (93% male, 40% Caucasian, 43% African American) followed for a median of 11 years. In 8.5% and 4.6% of the participants, respectively, LLV and HLLV were the highest recorded viremia strata. Compared with VS, SNAEs were associated with LLV (1.3 [1.2-1.4]), HLLV (1.6 [1.5-1.7]), and virologic failure (1.7 [1.7-1.8]). Conclusions: The results of this study suggest that LLV is associated with the occurrence of SNAEs and needs further study.

Gut microbiome and antibiotic resistance effects during travelers' diarrhea treatment and prevention.

IMPORTANCE: The travelers' gut microbiome is potentially assaulted by acute and chronic perturbations (e.g., diarrhea, antibiotic use, and different environments). Prior studies of the impact of travel and travelers' diarrhea (TD) on the microbiome have not directly compared antibiotic regimens, and studies of different antibiotic regimens have not considered travelers' microbiomes. This gap is important to be addressed as the use of antibiotics to treat or prevent TD-even in moderate to severe cases or in regions with high infectious disease burden-is controversial based on the concerns for unintended consequences to the gut microbiome and antimicrobial resistance (AMR) emergence. Our study addresses this by evaluating the impact of defined antibiotic regimens (single-dose treatment or daily prophylaxis) on the gut microbiome and resistomes of deployed servicemembers, using samples collected during clinical trials. Our findings indicate that the antibiotic treatment regimens that were studied generally do not lead to adverse effects on the gut microbiome and resistome and identify the relative risks associated with prophylaxis. These results can be used to inform therapeutic guidelines for the prevention and treatment of TD and make progress toward using microbiome information in personalized medical care.

SARS-CoV-2 infection is associated with self-reported post-acute neuropsychological symptoms within six months of follow-up.

BACKGROUND: Chronic neuropsychological sequelae following SARS-CoV-2 infection, including depression, anxiety, fatigue, and general cognitive difficulties, are a major public health concern. Given the potential impact of long-term neuropsychological impairment, it is important to characterize the frequency and predictors of this post-infection phenotype. METHODS: The Epidemiology, Immunology, and Clinical Characteristics of Emerging Infectious Diseases with Pandemic Potential (EPICC) study is a longitudinal study assessing the impact of SARS-CoV-2 infection in U.S. Military Healthcare System (MHS) beneficiaries, i.e. those eligible for care in the MHS including active duty servicemembers, dependents, and retirees. Four broad areas of neuropsychological symptoms were assessed cross-sectionally among subjects 1-6 months post-infection/enrollment, including: depression (Patient Health Questionnaire-9), anxiety (General Anxiety Disorder-7), fatigue (PROMIS® Fatigue 7a), and cognitive function (PROMIS® Cognitive Function 8a and PROMIS® Cognitive Function abilities 8a). Multivariable Poisson regression models compared participants with and without SARS-CoV-2 infection history on these measures, adjusting for sex, ethnicity, active-duty status, age, and months post-first positive or enrollment of questionnaire completion (MPFP/E); models for fatigue and cognitive function were also adjusted for depression and anxiety scores. RESULTS: The study population included 2383 participants who completed all five instruments within six MPFP/E, of whom 687 (28.8%) had at least one positive SARS-CoV-2 test. Compared to those who had never tested positive for SARS-CoV-2, the positive group was more likely to meet instrument-based criteria for depression (15.4% vs 10.3%, p<0.001), fatigue (20.1% vs 8.0%, p<0.001), impaired cognitive function (15.7% vs 8.6%, p<0.001), and impaired cognitive function abilities (24.3% vs 16.3%, p<0.001). In multivariable models, SARS-CoV-2 positive participants, assessed at an average of 2.7 months after infection, had increased risk of moderate to severe depression (RR: 1.44, 95% CI 1.12-1.84), fatigue (RR: 2.07, 95% CI 1.62-2.65), impaired cognitive function (RR: 1.64, 95% CI 1.27-2.11), and impaired cognitive function abilities (RR: 1.41, 95% CI 1.15-1.71); MPFP/E was not significant. CONCLUSIONS: Participants with a history of SARS-CoV-2 infection were up to twice as likely to report cognitive impairment and fatigue as the group without prior SARS-CoV-2 infection. These findings underscore the continued importance of preventing SARS-CoV-2 infection and while time since infection/enrollment was not significant through 6 months of follow-up, this highlights the need for additional research into the long-term impacts of COVID-19 to mitigate and reverse these neuropsychological outcomes.

Detecting Rickettsia parkeri infection from eschar swab specimens.

The typical clinical presentation of several spotted fever group Rickettsia infections includes eschars. Clinical diagnosis of the condition is usually made by analysis of blood samples. We describe a more sensitive, noninvasive means of obtaining a sample for diagnosis by using an eschar swab specimen from patients infected with Rickettsia parkeri.

The Impact of Infectious Disease Syndromes on Activities During Military Travel.

Background: We evaluated the impact of infectious disease (ID) syndromes on US active duty (AD) servicemembers returning from overseas deployment (DEP), military training exercises (EXR), or short-term military travel (eg, temporary assignment of duty [TDY]). Methods: We conducted a survey-based assessment of US AD servicemembers returning from DEP, EXR, or TDY between 2015 and 2019. Subjects completed a post-travel survey capturing symptoms of travelers' diarrhea (TD), influenza-like illness (ILI), and febrile illness (FI). Risk factors associated with any ID syndrome (ie, either TD, ILI, or FI) that impacted daily activities were assessed using a logistic regression model with backward selection. Results: One-third of servicemembers (654/1822) experienced an ID syndrome, and 26% (471/1822) reported a ≥50% reduction in activity level due to an ID syndrome (median duration, 3 days). TD was the most common ID syndrome experienced and accounted for 73% (346/471) of ID syndromes impacting daily activities. The greatest impact of ID syndromes was observed in servicemembers on DEP. Compared with servicemembers on EXR or TDY, those on DEP had a longer duration of travel and a delayed period of risk for ID syndromes. Multivariate analysis identified high-risk exposures (ie, environmental exposures, close contact with locals, consuming food from street vendors) and behaviors (ie, inability to sanitize hands before meals) that could be used to inform mitigation strategies. Conclusions: ID syndromes result in a significant loss of productivity during military travel. Addressing modifiable risk factors and access to TD self-treatment in high-risk settings may help mitigate the impact of ID threats during military travel.

A machine learning approach identifies distinct early-symptom cluster phenotypes which correlate with hospitalization, failure to return to activities, and prolonged COVID-19 symptoms.

BACKGROUND: Accurate COVID-19 prognosis is a critical aspect of acute and long-term clinical management. We identified discrete clusters of early stage-symptoms which may delineate groups with distinct disease severity phenotypes, including risk of developing long-term symptoms and associated inflammatory profiles. METHODS: 1,273 SARS-CoV-2 positive U.S. Military Health System beneficiaries with quantitative symptom scores (FLU-PRO Plus) were included in this analysis. We employed machine-learning approaches to identify symptom clusters and compared risk of hospitalization, long-term symptoms, as well as peak CRP and IL-6 concentrations. RESULTS: We identified three distinct clusters of participants based on their FLU-PRO Plus symptoms: cluster 1 ("Nasal cluster") is highly correlated with reporting runny/stuffy nose and sneezing, cluster 2 ("Sensory cluster") is highly correlated with loss of smell or taste, and cluster 3 ("Respiratory/Systemic cluster") is highly correlated with the respiratory (cough, trouble breathing, among others) and systemic (body aches, chills, among others) domain symptoms. Participants in the Respiratory/Systemic cluster were twice as likely as those in the Nasal cluster to have been hospitalized, and 1.5 times as likely to report that they had not returned-to-activities, which remained significant after controlling for confounding covariates (P < 0.01). Respiratory/Systemic and Sensory clusters were more likely to have symptoms at six-months post-symptom-onset (P = 0.03). We observed higher peak CRP and IL-6 in the Respiratory/Systemic cluster (P < 0.01). CONCLUSIONS: We identified early symptom profiles potentially associated with hospitalization, return-to-activities, long-term symptoms, and inflammatory profiles. These findings may assist in patient prognosis, including prediction of long COVID risk.