Treponema pallidum periplasmic and membrane proteins are recognized by circulating and skin CD4+ T cells

Background

Histologic and serologic studies suggest the induction of local and systemic Treponema pallidum ( Tp )-specific CD4+ T cell responses to Tp infection. We hypothesized that Tp -specific CD4+ T cells are detectable in blood and in the skin rash of secondary syphilis and persist in both compartments after treatment.

Methods

PBMC collected from 67 participants were screened by IFNγ ELISPOT response to Tp sonicate. Tp -reactive T cell lines from blood and skin were probed for responses to 88 recombinant Tp antigens. Peptide epitopes and HLA class II restriction were defined for selected antigens.

Results

We detected CD4+ T cell responses to Tp sonicate ex vivo. Using Tp -reactive T cell lines we observed recognition of 14 discrete proteins, 13 of which localize to bacterial membranes or the periplasmic space. After therapy, Tp -specific T cells persisted for at least 6 months in skin and 10 years in blood.

Conclusions

Tp infection elicits an antigen-specific CD4+ T cell response in blood and skin. Tp -specific CD4+ T cells persist as memory in both compartments long after curative therapy. The Tp antigenic targets we identified may be high priority vaccine candidates.

Severe Acute Respiratory Syndrome Coronavirus 2 Omicron Subvariant Neutralization Following a Primary Vaccine Series of NVX-CoV2373 and BNT162b2 Monovalent Booster Vaccine

We evaluated the immunologic response to a novel vaccine regimen that included 2 doses of NVX-CoV2373 (Novavax) followed by 1 dose of BNT162b2 (Pfizer-BioNTech) monovalent booster vaccine. A durable neutralizing antibody response to Omicron BA.4/BA.5 and BA.1 variants was observed at month 6 after the booster, while immune escape was noted for the XBB.1.5 variant.

Prior Herpes Simplex Virus Infection and the Risk of Herpes Zoster

BACKGROUND

The incidence of herpes zoster (HZ) has increased in the United States concurrent with decrease in herpes simplex virus (HSV) prevalence. We hypothesized that lack of HSV-elicited cross-reactive immunity to varicella-zoster virus (VZV) results in an increased risk of HZ. Using specimens from the placebo arm of the Shingles Prevention Study, we investigated whether persons who develop HZ are less likely to have prior HSV infection than persons who do not develop HZ, and whether HZ is less severe in persons with HSV than in HSV seronegative persons.

METHODS

We conducted a nested case-control (1:2) study comparing the seroprevalence of HSV-1 and HSV-2 in cases (persons with polymerase chain reaction-confirmed HZ) to age-, sex-, and health-matched controls (persons without HZ).

RESULTS

Sera from 639 study participants (213 cases and 426 controls) yielded definitive HSV antibody results and were analyzed. Overall, HSV seropositivity rate was 75%. HSV seronegativity was significantly higher in HZ cases than controls (30.5% vs 22.3%; P = .024), with a 55% higher risk of HZ in HSV seronegative than HSV seropositive participants. HSV seropositivity was associated with more severe HZ (P = .021).

CONCLUSIONS

Our study demonstrated that prior infection with HSV partly protects against HZ.

Repeated mRNA vaccination sequentially boosts SARS-CoV-2-specific CD8+ T cells in persons with previous COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) hybrid immunity is more protective than vaccination or previous infection alone. To investigate the kinetics of spike-reactive T (TS) cells from SARS-CoV-2 infection through messenger RNA vaccination in persons with hybrid immunity, we identified the T cell receptor (TCR) sequences of thousands of index TS cells and tracked their frequency in bulk TCRβ repertoires sampled longitudinally from the peripheral blood of persons who had recovered from coronavirus disease 2019 (COVID-19). Vaccinations led to large expansions in memory TS cell clonotypes, most of which were CD8+ T cells, while also eliciting diverse TS cell clonotypes not observed before vaccination. TCR sequence similarity clustering identified public CD8+ and CD4+ TCR motifs associated with spike (S) specificity. Synthesis of longitudinal bulk ex vivo single-chain TCRβ repertoires and paired-chain TCRɑβ sequences from droplet sequencing of TS cells provides a roadmap for the rapid assessment of T cell responses to vaccines and emerging pathogens.

Longitudinal assessment of bacterial vaginosis prior to and during incident pregnancy: an observational study in Kenyan adolescent girls and young women

OBJECTIVE

To determine bacterial vaginosis (BV) status at multiple time points among adolescent girls and young women (AGYW) and assess the impact of pregnancy on their BV status.

DESIGN

Longitudinal cohort study.

SETTING

Thika, Kenya.

PARTICIPANTS

AGYW aged 16-20 years enrolled prior to first sex or reporting only a single lifetime partner.

MAIN OUTCOME MEASURES

The primary outcome was relative risk (RR) of BV during pregnancy compared with before pregnancy by analysing longitudinal trends in BV over time. BV risk was estimated using Poisson regression models.

RESULTS

A total of 121 AGYW became pregnant in the parent cohort and had BV results before, during or after pregnancy. Point prevalence of BV was 11.0% at visits >12 months pre-pregnancy, 13.0% at 3-12 months pre-pregnancy, 22.1% at <3 months pre-pregnancy and 13.4% during pregnancy. Compared with visits during pregnancy, RR of BV was 1.65 (95% CI: 1.00 to 2.71; p=0.05) at visits <3 months pre-pregnancy, 0.97 (95% CI: 0.62 to 1.52; p=0.90) at visits 3-12 months pre-pregnancy and 0.82 (95% CI: 0.44 to 1.53; p=0.53) at visits 12 months pre-pregnancy. An adjusted analysis including age, income, residence, date of first sex, recent sexual activity and positive sexually transmitted infection test resulted in small changes in risk estimates, with adjusted RR of BV of 1.66 (95% CI: 1.04 to 2.67; p=0.04) at visits <3 months pre-pregnancy compared with visits during pregnancy.

CONCLUSIONS

BV risk during pregnancy was lower than during the immediate pre-pregnancy period. Hormonal changes in pregnancy may reduce BV.

Comparison of bivalent and monovalent SARS-CoV-2 variant vaccines: the phase 2 randomized open-label COVAIL trial

Vaccine protection against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection wanes over time, requiring updated boosters. In a phase 2, open-label, randomized clinical trial with sequentially enrolled stages at 22 US sites, we assessed safety and immunogenicity of a second boost with monovalent or bivalent variant vaccines from mRNA and protein-based platforms targeting wild-type, Beta, Delta and Omicron BA.1 spike antigens. The primary outcome was pseudovirus neutralization titers at 50% inhibitory dilution (ID50 titers) with 95% confidence intervals against different SARS-CoV-2 strains. The secondary outcome assessed safety by solicited local and systemic adverse events (AEs), unsolicited AEs, serious AEs and AEs of special interest. Boosting with prototype/wild-type vaccines produced numerically lower ID50 titers than any variant-containing vaccine against all variants. Conversely, boosting with a variant vaccine excluding prototype was not associated with decreased neutralization against D614G. Omicron BA.1 or Beta monovalent vaccines were nearly equivalent to Omicron BA.1 + prototype or Beta + prototype bivalent vaccines for neutralization of Beta, Omicron BA.1 and Omicron BA.4/5, although they were lower for contemporaneous Omicron subvariants. Safety was similar across arms and stages and comparable to previous reports. Our study shows that updated vaccines targeting Beta or Omicron BA.1 provide broadly crossprotective neutralizing antibody responses against diverse SARS-CoV-2 variants without sacrificing immunity to the ancestral strain. ClinicalTrials.gov registration: NCT05289037 .

Low prevalence of bacterial vaginosis in Kenyan adolescent girls and rapid incidence after first sex

BACKGROUND

Bacterial vaginosis is a risk factor for sexually transmitted infections, including HIV. Adult African women have a high prevalence of bacterial vaginosis, but it is not known when first bacterial vaginosis occurs.

OBJECTIVE

This study aimed to describe bacterial vaginosis in younger African women, before and after first sex, and to determine the incidence of bacterial vaginosis and significant correlates of bacterial vaginosis incidence and recurrence.

STUDY DESIGN

In a prospective observational cohort study enrolling adolescents with limited sexual experience, young women aged 16 to 21 years were recruited in Thika, Kenya. Eligible participants were HIV and herpes simplex virus 2 seronegative and reported 0 or 1 lifetime sexual partner. The Nugent score was determined at quarterly visits from vaginal Gram stains. The trends in bacterial vaginosis were described over time; hazard ratios were calculated using Cox regression, and relative risk of bacterial vaginosis was estimated using generalized estimating equations and Poisson regression.

RESULTS

A total of 400 participants with a median age of 18.6 years (interquartile range, 16-21) were enrolled. Of note, 322 participants (80.5%) reported no history of sex, whereas 78 participants (19.5%) reported sex with 1 partner. At enrollment, bacterial vaginosis (Nugent score of ≥7) was uncommon (21/375 [5.6%]). Overall, 144 participants had bacterial vaginosis at least once, for an incidence rate of 16.5 cases per 100 person-years. Before first sex, bacterial vaginosis was present at 2.8% of visits, compared with 13.7% of visits after first sex. An adjusted model of bacterial vaginosis incidence observed that first sex was associated with more than a 2-fold increased bacterial vaginosis risk (adjusted hazard ratio, 2.44; 95% confidence interval, 1.25-4.76; P=.009). Chlamydia diagnosis (adjusted hazard ratio, 1.73; 95% confidence interval, 1.1-2.8; P=.02), and herpes simplex virus 2 seropositivity (adjusted hazard ratio, 2.88; 95% confidence interval, 1.17-7.09; P=.021) were both associated with incident bacterial vaginosis. A multivariate generalized estimating equation model, including all episodes of bacterial vaginosis, demonstrated risk factors, including first sex, sexually transmitted infections, urban residence, recent sex, and no income; the most important risk factor was first sex (adjusted relative risk, 1.92; 95% confidence interval, 1.12-3.31; P=.018). The probability of bacterial vaginosis increased with each subsequent episode; mean Nugent scores increased after each bacterial vaginosis episode.

CONCLUSION

Using detailed longitudinal observation, this study found that Kenyan adolescents have almost no bacterial vaginosis before first sex and that initiation of sexual activity was the strongest risk factor for both prevalent bacterial vaginosis and incident bacterial vaginosis.

Health equity necessitates the inclusion of gender identity data in COVID-19 clinical trials

COVID-19 has highlighted the importance of studying differences by sex and gender. The under-reporting of gender identity in COVID-19 studies limits the generalizability of study results to nonbinary persons. Some of the data on sex-assigned associated complications of both COVID-19 infection and COVID-19 immunizations is presented in this manuscript.

Increased frequency and quantity of mucosal and plasma cytomegalovirus replication among Ugandan Adults Living with HIV

BACKGROUND

Co-infection with HIV can result in impaired control of cytomegalovirus (CMV) replication, increasing the likelihood of disease and onward transmission. The objective of this analysis was to measure the impact of HIV on CMV replication in an intensively-sampled cohort in Kampala, Uganda.

METHODS

CMV seropositive men and women aged 18-65, with or without HIV co-infection, were followed for one month. Daily oral swabs and weekly anogenital swabs and plasma were collected. Quantitative CMV PCR was performed on all samples.

RESULTS

Eighty-five participants were enrolled and provided ≥1 oral swab; 43 (51%) were HIV-seropositive. People living with HIV (PLWH; median CD4 count 439 cells/mm3; none on antiretrovirals) had 2-4 times greater risk of CMV detection at each anatomical site assessed. At the oral site, 773 of 1272 (61%) of samples from PLWH had CMV detected, compared to 214 of 1349 (16%) among people without HIV. Similarly, the mean CMV quantity was higher among PLWH at all anatomical sites, with the largest difference seen for oral swabs (mean difference 1.63 log/mL; 95% CI 1.13-2.13). Among PLWH, absolute quantity of CD4+ T-cells was not associated with risk of CMV detection. HIV plasma RNA quantity was positively correlated with oral CMV shedding frequency, but not detection at other sites.

CONCLUSIONS

Mucosal and systemic CMV replication occurs at higher levels in PLWH than people without HIV, particularly oral shedding, which is a major mode of CMV transmission. Increased CMV replication despite relatively preserved CD4+ T-cell counts suggests that additional interventions are required to improve CMV control in PLWH.

"I was just concerned about getting pregnant": Attitudes toward pregnancy and contraceptive use among adolescent girls and young women in Thika, Kenya

BACKGROUND

Adolescent girls and young women (AGYW) have a high incidence of unplanned pregnancies, especially in low-resource settings. AGYW assess the overlapping risks of pregnancy, contraception, and STIs as they navigate relationships. Few studies have examined how AGYW consider the comparative risks of their decisions around sexual and reproductive health in this context or how risk perception influences contraceptive use.

METHODS

Twenty in-depth interviews (IDIs) and 5 focus group discussions (FGDs) were conducted with a subset of sexually active AGYW enrolled in the Girls Health Study (GHS), a longitudinal cohort study in Thika, Kenya, assessing HSV-2 incidence in a cohort of AGYW aged 16-20. Interview questions were focused on perspectives and decision-making around sexual and reproductive health. Interviews were conducted in both English and Kiswahili, transcribed, and coded using inductive and deductive approaches to identify emerging themes.

RESULTS

Misconceptions about long-acting reversible contraceptives (LARCs), injectables, and daily oral contraceptive pills strongly disincentivized their use among AGYW. Participants described pregnancy as undesirable, and AGYW reported prioritizing contraceptive methods that were effective and reliable in pregnancy prevention, even if not effective in preventing STI/HIV infection. Participants reported that AGYW relied heavily on emergency contraceptive (EC) pills for pregnancy prevention.

CONCLUSIONS

Though the goal of avoiding unintended pregnancy was common, this did not suffice to motivate the uptake of long-term contraceptives among AGYWs. Given the convenience, cost-effectiveness, and lower perceived risk of side effects, EC pills were more likely to be accepted as a form of contraception. Understanding the reasons for AGYW's acceptance of certain contraceptive methods over others can help future interventions better target communication and counseling about contraception and influence key drivers of AGYW behavior and decision-making around sexual and reproductive health.

Bivalent and Monovalent SARS-CoV-2 Variant Vaccine Boosters Improve coverage of the known Antigenic Landscape: Results of the COVID-19 Variant Immunologic Landscape (COVAIL) Trial

Vaccine protection against COVID-19 wanes over time and has been impacted by the emergence of new variants with increasing escape of neutralization. The COVID-19 Variant Immunologic Landscape (COVAIL) randomized clinical trial (clinicaltrials.gov NCT05289037) compares the breadth, magnitude and durability of antibody responses induced by a second COVID-19 vaccine boost with mRNA (Moderna mRNA-1273 and Pfizer-BioNTech BNT162b2), or adjuvanted recombinant protein (Sanofi CoV2 preS DTM-AS03) monovalent or bivalent vaccine candidates targeting ancestral and variant SARS-CoV-2 spike antigens (Beta, Delta and Omicron BA.1). We found that boosting with a variant strain is not associated with loss in neutralization against the ancestral strain. However, while variant vaccines compared to the prototype/wildtype vaccines demonstrated higher neutralizing activity against Omicron BA.1 and BA.4/5 subvariants for up to 3 months after vaccination, neutralizing activity was lower for more recent Omicron subvariants. Our study, incorporating both antigenic distances and serologic landscapes, can provide a framework for objectively guiding decisions for future vaccine updates.

Adolescent Girls and Young Women in Kenya Demonstrate Rapid STI Incidence Following First Sex: Data From a Longitudinal Cohort

PURPOSE

Adolescent girls and young women (AGYW) are disproportionately affected by STIs. Observation of life course events can describe behavioral and biological factors associated with STI risk.

METHODS

Sexually inexperienced AGYW aged 16-20 years in Kenya were followed for five years. Quarterly visits assessed for C. trachomatis (CT), N. gonorrhea (GC), and T. vaginalis (TV), bacterial vaginosis (BV), HSV-2, and HIV. Sexual activity was self-reported but amended if incongruent with results from STI, pregnancy, or any other testing. Cox regression and Generalized Estimating Equation models were used to determine hazard ratios (HRs) and relative risks (RRs) of STI.

RESULTS

During follow-up, 293 of 400 participants reported sex, 163 AGYW experienced an STI, and 72 participants had multiple STIs. Among 163 participants that experienced an STI, there were a total of 259 visits where STIs were detected, 78% (n = 201) of which included CT. Cox regression found participants with BV had over two-fold higher risk of first STI acquisition (adjusted hazard ratio (aHR): 2.35; 95% confidence interval (CI) 1.43-3.88; p = .001). Increased risk for first STI episode was associated with a new partner (aHR: 3.16; 95% CI 1.59-6.28; p = .001). AGYW who did not disclose sexual activity had the highest risk (aHR: 3.60; 95% CI 1.93-6.70; p < .001). Condom use was low, with 21% reporting condom use with sex. GEE analysis of all STIs including incident, prevalent, and recurrent, confirmed these risk factors.

DISCUSSION

During the critical years after first sex, AGYW with BV, new sexual partners, and those who did not disclose sexual activity were at highest risk for STI events, especially CT.

Genital Herpes Simplex Virus Type 2 Suppression With Valacyclovir Is Not Associated With Changes in Nugent Score or Absolute Abundance of Key Vaginal Bacteria

Background

In women, genital herpes simplex virus type 2 (HSV-2) infection is associated with increased risk for recurrent bacterial vaginosis (BV), but causal relationships are unclear.

Methods

Women with a self-reported history of BV and HSV-2 seropositivity self-collected vaginal and anogenital swabs for 2 nonconsecutive 28-day periods, in the absence or presence of valacyclovir suppressive therapy (500 mg daily). HSV polymerase chain reaction was performed on anogenital swabs; vaginal swabs were used for assessment of BV by Nugent score and quantification of vaginal microbiota. Days with BV, defined by Nugent score ≥7, were compared during the observational period and valacyclovir treatment.

Results

Forty-one women collected swabs for a median of 28 days (range, 20-32 days) each study period. The HSV-2 shedding rate decreased from 109 of 1126 days (9.7%) presuppression to 6 of 1125 days (0.05%) during valacyclovir (rate ratio [RR], 0.06 [95% confidence interval {CI}, .02-.13]). BV occurred on 343 of 1103 days (31.1%) during observation and 302 of 1091 days (27.7%) during valacyclovir (RR, 0.90 [95% CI, .68-1.20]). The median per-person Nugent score was 3.8 during observation and 4.0 during valacyclovir. Average log₁₀ concentrations of vaginal bacterial species did not change significantly during valacyclovir treatment.

Conclusions

Short-term HSV-2 suppression with valacyclovir did not significantly affect the Nugent score or the vaginal microbiome despite potent suppression of HSV-2 shedding.

The Coronavirus Disease 2019 Pandemic Unmasked the Challenges Faced by Early-Stage Faculty in Infectious Diseases: A Call to Action

The coronavirus disease 2019 (COVID-19) pandemic and associated increase in family care responsibilities resulted in unsustainable personal and professional workloads for infectious diseases (ID) faculty on the front lines. This was especially true for early-stage faculty (ESF), many of whom had caregiving responsibilities. In addition, female faculty, underrepresented in medicine and science faculty and particularly ESF, experienced marked declines in research productivity, which significantly impacts career trajectories. When combined with staffing shortages due to an aging workforce and suboptimal recruitment and retention in ID, these work-life imbalances have brought the field to an inflection point. We propose actionable recommendations and call on ID leaders to act to close the gender, racial, and ethnic gaps to improve the recruitment, retention, and advancement of ESF in ID. By investing in systemic change to make the ID workforce more equitable, we can embody the shared ideals of diversity and inclusion and prepare for the next pandemic.

Dynamics of SARS-CoV-2 VOC Neutralization and Novel mAb Reveal Protection against Omicron

New variants of SARS-CoV-2 continue to emerge and evade immunity. We isolated SARS-CoV-2 temporally across the pandemic starting with the first emergence of the virus in the western hemisphere and evaluated the immune escape among variants. A clinic-to-lab viral isolation and characterization pipeline was established to rapidly isolate, sequence, and characterize SARS-CoV-2 variants. A virus neutralization assay was applied to quantitate humoral immunity from infection and/or vaccination. A panel of novel monoclonal antibodies was evaluated for antiviral efficacy. We directly compared all variants, showing that convalescence greater than 5 months post-symptom onset from ancestral virus provides little protection against SARS-CoV-2 variants. Vaccination enhances immunity against viral variants, except for Omicron BA.1, while a three-dose vaccine regimen provides over 50-fold enhanced protection against Omicron BA.1 compared to a two-dose. A novel Mab neutralizes Omicron BA.1 and BA.2 variants better than the clinically approved Mabs, although neither can neutralize Omicron BA.4 or BA.5. Thus, the need remains for continued vaccination-booster efforts, with innovation for vaccine and Mab improvement for broadly neutralizing activity. The usefulness of specific Mab applications links with the window of clinical opportunity when a cognate viral variant is present in the infected population.

101. Effect of Human Papillomavirus Vaccine to Interrupt Recurrence of Vulvar and Anal Neoplasia (VIVA): A Randomized, Placebo-Controlled Trial

Background

Anal and vulvar high-grade intraepithelial lesions (HSIL) often recur after primary treatment, with 30%-50% recurrence in the 5-years following treatment. Treatment for recurrent lesions can be uncomfortable, debilitating, and costly. The VIVA trial evaluated the effects of the nonavalent human papillomavirus (HPV) vaccine (9vHPV) on recurrent anal or vulvar HSIL.

Methods

We conducted a randomized, double-blinded, placebo-controlled trial of the 9vHPV in vaccine-naïve persons aged 27-69 years who were previously treated for anal or vulvar HSIL and HSIL-free at enrollment. Participants had high-resolution anoscopy or vulvoscopy at screening, month 18 and 36 visits. Eligible participants were randomly assigned (1:1) to receive 9vHPV or placebo on day 1, month 2 and 6. We hypothesized that 9vHPV leads to a 50% reduction of HSIL recurrence. The primary endpoint was anal or vulvar HSIL recurrence, which was assessed in the intent-to-treat (ITT) population.

Results

Between July 2017 and December 2021, 187participants (99 cis-men, 86 cis-women, 2 transgender persons) with a history of anal (104, 56%) or vulvar (83, 44%) HSIL enrolled in the trial. 181 (97%) participants were included in the ITT analysis. Median age was 55 years (IQR 48-63); 71 out of 181 participants (39%) had well-controlled HIV infection. The DSMB recommended stopping the study early because it met specified futility boundaries at interim analysis. Predictive power to show a significant difference in the primary endpoint was 6.4% should the study continue to accrue. With 46% of planned information accrued, the vaccine was not significantly more efficacious than the placebo in preventing recurrent HSIL, with 15 cases in the 9vHPV arm versus 18 cases in placebo (incidence 9.1 versus 10.0/100 person-years; p= 0.83 by log-rank test). We found no differences in HSIL recurrences among vaccine versus placebo recipients by anatomical site or HIV status. The 9vHPV was safe and well-tolerated.

Kaplan-Meier Curve for overall high-grade squamous intra-epithelial neoplasia (HSIL) recurrences for nonavalent-HPV vaccine vs placebo recipients

Conclusion

We found no benefit of the 9vHPV vaccine for prevention of recurrent anal or vulvar HSIL. Our study underlines the importance of HPV prevention with prophylactic HPV vaccines and the need for novel therapeutic vaccines and antivirals to manage prevalent HSIL that have a high potential to recur.

Disclosures

Denise Galloway, PhD, Merck: Grant/Research Support Anna Wald, MD, MPH, Aicuris: Advisor/Consultant|Auritec: Advisor/Consultant|Crozet: Advisor/Consultant|DXNow: Advisor/Consultant|GSK: Grant/Research Support|Merck: Advisor/Consultant|sanofi: Grant/Research Support|VIR: Advisor/Consultant|X-Vax: Advisor/Consultant.

1948. Evaluation of a heterologous booster vaccine regimen: Pfizer-BioNTech BNT162b2 mRNA booster vaccine following priming with Novavax NVX-CoV2373

Background

In the United States, booster vaccines for persons 18 years and older were approved under Emergency Use Authorization (EUA) in September 2021. Waning immunity following SARS-CoV-2 primary vaccination series led to recommendations for booster vaccination. Emerging data suggest that providing boosters different from the primary series (heterologous vaccination) may provide a broader immune response than boosting with the same vaccine (homologous vaccination). CDC recommended the Pfizer-BioNTech BNT162b2 30-μg mRNA booster vaccine to clinical trial participants &gt;6 months post study vaccines if not planned for boosting within the study.

Methods

We conducted an observational study of persons who received 2 doses of Novavax protein-based NVX-CoV2373 vaccine 21 days apart, in a Phase 3 clinical trial, and subsequently received a Pfizer BNT162b2 booster vaccine under EUA. Serologic assays, including the Roche anti-nucleocapsid (N) IgG and anti-Spike (S) IgG, were performed on blood collected pre-booster (D0) and on days 18 (D18) and 34 (D34) post-booster vaccine. The anti-S IgG geometric means (GMTs) were calculated over study time points. Wilcoxon signed rank test was performed to compare anti-S IgG response between D0 and D18 and D0 and D34.

Results

Of 26 participants enrolled, 16 (57%) were women; the median age was 47 years (range 29-67). Roche anti-N antibodies were negative at all visits. Time from second NVX-CoV2373 vaccine to Pfizer BNT162b2 booster was a median of 10.4 months in 54% of participants and 7 months in 46% of participants. Anti-S IgG GMTs were 222 BAU/ml D0, 24,723 BAU/ml D18, and 24,584 BAU/ml D34 (p&lt; 0.0001 for comparisons of D0 with D18 & D34). Overall, participants tolerated the booster vaccine without significant adverse events. Cell mediated immunity and D614G pseudovirus neutralizing antibody assays are in progress. Figure 1.Anti-S IgG titers pre and post-booster vaccine

16 participants included with all 3-time study time points for comparison.

Conclusion

Two doses of NVX-CoV2373 vaccine followed by the Pfizer BNT162b2 booster vaccine resulted in ∼100-fold increase in anti-S IgG against SARS-CoV-2. No participant had evidence of prior SARS-CoV-2 infection by anti-N IgG. Two doses of NVX-CoV2373 vaccine followed by one dose of Pfizer BNT162b2 vaccine is an effective and well-tolerated regimen for boosting anti-S IgG against SARS-CoV-2.

Disclosures

Christine Johnston, MD, MPH, AbbVie: Advisor/Consultant|Gilead: Grant/Research Support|GSK: Advisor/Consultant Kerry J. Laing, PhD, Curevo Vaccine: Advisor/Consultant|MaxHealth Biotechnology: Advisor/Consultant|Sanofi Pasteur: Grant/Research Support David M. Koelle, MD, Curevo Vaccines: Advisor/Consultant|MaxHealth LLC: Advisor/Consultant|Oxford Immunotec: gift of reagents|Sanofi: Grant/Research Support|Sensei: Grant/Research Support Alexander L. Greninger, MD, PhD, Abbott: Contract Testing|Cepheid: Contract Testing|Gilead: Grant/Research Support|Gilead: Contract Testing|Hologic: Contract Testing|Merck: Grant/Research Support|Novavax: Contract Testing|Pfizer: Contract Testing Anna Wald, MD, MPH, Aicuris: Advisor/Consultant|Auritec: Advisor/Consultant|Crozet: Advisor/Consultant|DXNow: Advisor/Consultant|GSK: Grant/Research Support|Merck: Advisor/Consultant|sanofi: Grant/Research Support|VIR: Advisor/Consultant|X-Vax: Advisor/Consultant.

Using time-weighted average change from baseline of SARS-CoV-2 viral load to assess impact of hydroxychloroquine as postexposure prophylaxis and early treatment for COVID-19

Two randomized controlled trials demonstrated no clinical benefit of hydroxychloroquine (HCQ) for either postexposure prophylaxis or early treatment of SARS-CoV-2 infection. Using data from these studies, we calculated the time-weighted average change from baseline SARS-CoV-2 viral load and demonstrated that HCQ did not affect viral clearance.

Viral Shedding 1 Year Following First-Episode Genital HSV-1 Infection

IMPORTANCE

Herpes simplex virus type 1 (HSV-1) is the leading cause of first-episode genital herpes in many countries.

OBJECTIVE

To inform counseling messages regarding genital HSV-1 transmission, oral and genital viral shedding patterns among persons with first-episode genital HSV-1 infection were assessed. The trajectory of the development of HSV-specific antibody and T-cell responses was also characterized.

DESIGN, SETTING, AND PARTICIPANTS

Prospective cohort followed up for up to 2 years, with 82 participants followed up between 2013 and 2018. Participants were recruited from sexual health and primary care clinics in Seattle, Washington. Persons with laboratory-documented first-episode genital HSV-1 infection, without HIV infection or current pregnancy, were referred for enrollment.

EXPOSURES

First-episode genital HSV-1 infection.

MAIN OUTCOMES AND MEASURES

Genital and oral HSV-1 shedding and lesion rates at 2 months, 11 months, and up to 2 years after initial genital HSV-1 infection. Participants self-collected oral and genital swabs for HSV polymerase chain reaction testing for 30 days at 2 and 11 months and up to 2 years after diagnosis of genital HSV-1. Blood samples were collected at serial time points to assess immune responses to HSV-1. Primary HSV-1 infection was defined as absent HSV antibody at baseline or evolving antibody profile using the University of Washington HSV Western Blot. HSV-specific T-cell responses were detected using interferon γ enzyme-linked immunospot.

RESULTS

Among the 82 participants, the median (range) age was 26 (16-64) years, 54 (65.9%) were women, and 42 (51.2%) had primary HSV-1 infection. At 2 months, HSV-1 was detected from the genital tract in 53 participants (64.6%) and in the mouth in 24 participants (29.3%). Genital HSV-1 shedding was detected on 275 of 2264 days (12.1%) at 2 months and declined significantly to 122 of 1719 days (7.1%) at 11 months (model-predicted rate, 6.2% [95% CI, 4.3%-8.9%] at 2 months vs 3.2% [95% CI, 1.8%-5.7%] at 11 months; relative risk, 0.52 [95% CI, 0.29-0.93]). Genital lesions were rare, reported on 65 of 2497 days (2.6%) at 2 months and 72 of 1872 days (3.8%) at 11 months. Oral HSV-1 shedding was detected on 88 of 2247 days (3.9%) at 2 months. Persons with primary HSV-1 infection had a higher risk of genital shedding compared with those with nonprimary infection (model-predicted rate, 7.9% [95% CI, 5.4%-11.7%] vs 2.9% [95% CI, 1.7%-5.0%]; relative risk, 2.75 [95% CI, 1.40-5.44]). Polyfunctional HSV-specific CD4+ and CD8+ T-cell responses were maintained during the follow-up period.

CONCLUSIONS AND RELEVANCE

Genital HSV-1 shedding was frequent after first-episode genital HSV-1, particularly among those with primary infection, and declined rapidly during the first year after infection.

A multifaceted high-throughput assay for probing antigen-specific antibody-mediated primary monocyte phagocytosis and downstream functions

Monocytes are highly versatile innate immune cells responsible for pathogen clearance, innate immune coordination, and induction of adaptive immunity. Monocytes can directly and indirectly integrate pathogen-destructive instructions and contribute to disease control via pathogen uptake, presentation, or the release of cytokines. Indirect pathogen-specific instructions are conferred via Fc-receptor signaling and triggered by antibody opsonized material. Given the tremendous variation in polyclonal humoral immunity, defining the specific antibody-responses able to arm monocytes most effectively remains incompletely understood. While monocyte cell line-based assays have been used previously, cell lines may not faithfully recapitulate the full biology of monocytes. Thus, here we describe a multifaceted antigen-specific method for probing antibody-dependent primary monocyte phagocytosis (ADMP) and secondary responses. The assay not only reliably captures phagocytic uptake of immune complexes, but also detects unique changes in surface markers and cytokine secretions profiles, poorly detected by monocytic cell lines. The assay captures divergent polyclonal-monocyte recruiting activity across subjects with varying SARS-CoV-2 disease severity and also revealed biological nuances in Fc-mutant monoclonal antibody activity related to differences in Fc-receptor binding. Thus, the ADMP assay is a flexible assay able to provide key insights into the role of humoral immunity in driving monocyte phenotypic transitions and downstream functions across many diseases.

CD8+ T cell clonotypes from prior SARS-CoV-2 infection predominate during the cellular immune response to mRNA vaccination

Almost three years into the SARS-CoV-2 pandemic, hybrid immunity is highly prevalent worldwide and more protective than vaccination or prior infection alone. Given emerging resistance of variant strains to neutralizing antibodies (nAb), it is likely that T cells contribute to this protection. To understand how sequential SARS-CoV-2 infection and mRNA-vectored SARS-CoV-2 spike (S) vaccines affect T cell clonotype-level expansion kinetics, we identified and cross-referenced TCR sequences from thousands of S-reactive single cells against deeply sequenced peripheral blood TCR repertoires longitudinally collected from persons during COVID-19 convalescence through booster vaccination. Successive vaccinations recalled memory T cells and elicited antigen-specific T cell clonotypes not detected after infection. Vaccine-related recruitment of novel clonotypes and the expansion of S-specific clones were most strongly observed for CD8+ T cells. Severe COVID-19 illness was associated with a more diverse CD4+ T cell response to SARS-CoV-2 both prior to and after mRNA vaccination, suggesting imprinting of CD4+ T cells by severe infection. TCR sequence similarity search algorithms revealed myriad public TCR clusters correlating with human leukocyte antigen (HLA) alleles. Selected TCRs from distinct clusters functionally recognized S in the predicted HLA context, with fine viral peptide requirements differing between TCRs. Most subjects tested had S-specific T cells in the nasal mucosa after a 3rd mRNA vaccine dose. The blood and nasal T cell responses to vaccination revealed by clonal tracking were more heterogeneous than nAb boosts. Analysis of bulk and single cell TCR sequences reveals T cell kinetics and diversity at the clonotype level, without requiring prior knowledge of T cell epitopes or HLA restriction, providing a roadmap for rapid assessment of T cell responses to emerging pathogens.

Detection and Kinetics of Subgenomic Severe Acute Respiratory Syndrome Coronavirus 2 RNA Viral Load in Longitudinal Diagnostic RNA-Positive Samples

While detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by diagnostic reverse-transcription polymerase chain reaction (RT-PCR) is highly sensitive for viral RNA, the nucleic acid amplification of subgenomic RNAs (sgRNAs) that are the product of viral replication may more accurately identify replication. We characterized the diagnostic RNA and sgRNA detection by RT-PCR from nasal swab samples collected daily by participants in postexposure prophylaxis or treatment studies for SARS-CoV-2. Among 1932 RT-PCR-positive swab samples with sgRNA tests, 40% (767) had detectable sgRNA. Above a diagnostic RNA viral load (VL) threshold of 5.1 log10 copies/mL, 96% of samples had detectable sgRNA with VLs that followed a linear trend. The trajectories of diagnostic RNA and sgRNA VLs differed, with 80% peaking on the same day but duration of sgRNA detection being shorter (8 vs 14 days). With a large sample of daily swab samples we provide comparative sgRNA kinetics and a diagnostic RNA threshold that correlates with replicating virus independent of symptoms or duration of illness.

Dynamics of SARS-CoV-2 VOC neutralization and novel mAb reveal protection against Omicron

To evaluate SARS-CoV-2 variants we isolated SARS-CoV-2 temporally during the pandemic starting with first appearance of virus in the Western hemisphere near Seattle, WA, USA, and isolated each known major variant class, revealing the dynamics of emergence and complete take-over of all new cases by current Omicron variants. We assessed virus neutralization in a first-ever full comparison across variants and evaluated a novel monoclonal antibody (Mab). We found that convalescence greater than 5-months provides little-to-no protection against SARS-CoV-2 variants, vaccination enhances immunity against variants with the exception of Omicron BA.1, and paired testing of vaccine sera against ancestral virus compared to Omicron BA.1 shows that 3-dose vaccine regimen provides over 50-fold enhanced protection against Omicron BA.1 compared to a 2-dose regimen. We also reveal a novel Mab that effectively neutralizes Omicron BA.1 and BA.2 variants over clinically-approved Mabs. Our observations underscore the need for continued vaccination efforts, with innovation for vaccine and Mab improvement, for protection against variants of SARS-CoV-2.

Summary

We isolated SARS-CoV-2 temporally starting with emergence of virus in the Western hemisphere. Neutralization analyses across all variant lineages show that vaccine-boost regimen provides protection against Omicron BA.1. We reveal a Mab that protects against Omicron BA.1 and BA.2 variants.

Isoniazid preventive therapy and tuberculosis transcriptional signatures in people with HIV

OBJECTIVES

To examine the association between isoniazid preventive therapy (IPT) or nontuberculous mycobacteria (NTM) sputum culture positivity and tuberculosis (TB) transcriptional signatures in people with HIV.

DESIGN

Cross-sectional study.

METHODS

We enrolled adults living with HIV who were IPT-naive or had completed IPT more than 6 months prior at HIV care clinics in western Kenya. We calculated TB signatures using gene expression data from qRT-PCR. We used multivariable linear regression to analyze the association between prior receipt of IPT or NTM sputum culture positivity with a transcriptional TB risk score, RISK6 (range 0-1). In secondary analyses, we explored the association between IPT or NTM positivity and four other TB transcriptional signatures.

RESULTS

Among 381 participants, 99.7% were receiving antiretroviral therapy and 86.6% had received IPT (completed median of 1.1 years prior). RISK6 scores were lower (mean difference 0.10; 95% confidence interval (CI): 0.06-0.15; P  < 0.001) among participants who received IPT than those who did not. In a model that adjusted for age, sex, duration of ART, and plasma HIV RNA, the RISK6 score was 52.8% lower in those with a history of IPT ( P  < 0.001). No significant association between year of IPT receipt and RISK6 scores was detected. There was no association between NTM sputum culture positivity and RISK6 scores.

CONCLUSION

In people with HIV, IPT was associated with significantly lower RISK6 scores compared with persons who did not receive IPT. These data support investigations of its performance as a TB preventive therapy response biomarker.

SARS-CoV-2 Variant Vaccine Boosters Trial: Preliminary Analyses

Background

Protection from SARS-CoV-2 vaccines wanes over time and is compounded by emerging variants including Omicron subvariants. This study evaluated safety and immunogenicity of SARS-CoV-2 variant vaccines.

Methods

This phase 2 open-label, randomized trial enrolled healthy adults previously vaccinated with a SARS-CoV-2 primary series and a single boost. Eligible participants were randomized to one of six Moderna COVID19 mRNA vaccine arms (50µg dose): Prototype (mRNA-1273), Omicron BA.1+Beta (1 or 2 doses), Omicron BA.1+Delta, Omicron BA.1 monovalent, and Omicron BA.1+Prototype. Neutralization antibody titers (ID 50 ) were assessed for D614G, Delta, Beta and Omicron BA.1 variants and Omicron BA.2.12.1 and BA.4/BA.5 subvariants 15 days after vaccination.

Results

From March 30 to May 6, 2022, 597 participants were randomized and vaccinated. Median age was 53 years, and 20% had a prior SARS-CoV-2 infection. All vaccines were safe and well-tolerated. Day 15 geometric mean titers (GMT) against D614G were similar across arms and ages, and higher with prior infection. For uninfected participants, Day 15 Omicron BA.1 GMTs were similar across Omicron-containing vaccine arms (3724-4561) and higher than Prototype (1,997 [95%CI:1,482-2,692]). The Omicron BA.1 monovalent and Omicron BA.1+Prototype vaccines induced a geometric mean ratio (GMR) to Prototype for Omicron BA.1 of 2.03 (97.5%CI:1.37-3.00) and 1.56 (97.5%CI:1.06-2.31), respectively. A subset of samples from uninfected participants in four arms were also tested in a different laboratory at Day 15 for neutralizing antibody titers to D614G and Omicron subvariants BA.1, BA.2.12.2 and BA.4/BA.5. Omicron BA.4/BA.5 GMTs were approximately one third BA.1 GMTs (Prototype 517 [95%CI:324-826] vs. 1503 [95%CI:949-2381]; Omicron BA.1+Beta 628 [95%CI:367-1,074] vs. 2125 [95%CI:1139-3965]; Omicron BA.1+Delta 765 [95%CI:443-1,322] vs. 2242 [95%CI:1218-4128] and Omicron BA.1+Prototype 635 [95%CI:447-903] vs. 1972 [95%CI:1337-2907).

Conclusions

Higher Omicron BA.1 titers were observed with Omicron-containing vaccines compared to Prototype vaccine and titers against Omicron BA.4/BA.5 were lower than against BA.1 for all candidate vaccines.

Clinicaltrialsgov

NCT05289037.

T cell receptor sequencing identifies prior SARS-CoV-2 infection and correlates with neutralizing antibodies and disease severity

BACKGROUNDMeasuring the immune response to SARS-CoV-2 enables assessment of past infection and protective immunity. SARS-CoV-2 infection induces humoral and T cell responses, but these responses vary with disease severity and individual characteristics.METHODSA T cell receptor (TCR) immunosequencing assay was conducted using small-volume blood samples from 302 individuals recovered from COVID-19. Correlations between the magnitude of the T cell response and neutralizing antibody (nAb) titers or indicators of disease severity were evaluated. Sensitivity of T cell testing was assessed and compared with serologic testing.RESULTSSARS-CoV-2-specific T cell responses were significantly correlated with nAb titers and clinical indicators of disease severity, including hospitalization, fever, and difficulty breathing. Despite modest declines in depth and breadth of T cell responses during convalescence, high sensitivity was observed until at least 6 months after infection, with overall sensitivity ~5% greater than serology tests for identifying prior SARS-CoV-2 infection. Improved performance of T cell testing was most apparent in recovered, nonhospitalized individuals sampled > 150 days after initial illness, suggesting greater sensitivity than serology at later time points and in individuals with less severe disease. T cell testing identified SARS-CoV-2 infection in 68% (55 of 81) of samples with undetectable nAb titers (<1:40) and in 37% (13 of 35) of samples classified as negative by 3 antibody assays.CONCLUSIONThese results support TCR-based testing as a scalable, reliable measure of past SARS-CoV-2 infection with clinical value beyond serology.TRIAL REGISTRATIONSpecimens were accrued under trial NCT04338360 accessible at clinicaltrials.gov.FUNDINGThis work was funded by Adaptive Biotechnologies, Frederick National Laboratory for Cancer Research, NIAID, Fred Hutchinson Joel Meyers Endowment, Fast Grants, and American Society for Transplantation and Cell Therapy.

Comparison of herpes simplex virus 1 genomic diversity between adult sexual transmission partners with genital infection

Herpes simplex virus (HSV) causes chronic infection in the human host, characterized by self-limited episodes of mucosal shedding and lesional disease, with latent infection of neuronal ganglia. The epidemiology of genital herpes has undergone a significant transformation over the past two decades, with the emergence of HSV-1 as a leading cause of first-episode genital herpes in many countries. Though dsDNA viruses are not expected to mutate quickly, it is not yet known to what degree the HSV-1 viral population in a natural host adapts over time, or how often viral population variants are transmitted between hosts. This study provides a comparative genomics analysis for 33 temporally-sampled oral and genital HSV-1 genomes derived from five adult sexual transmission pairs. We found that transmission pairs harbored consensus-level viral genomes with near-complete conservation of nucleotide identity. Examination of within-host minor variants in the viral population revealed both shared and unique patterns of genetic diversity between partners, and between anatomical niches. Additionally, genetic drift was detected from spatiotemporally separated samples in as little as three days. These data expand our prior understanding of the complex interaction between HSV-1 genomics and population dynamics after transmission to new infected persons.

HSV-2-Specific Human Female Reproductive Tract Tissue Resident Memory T Cells Recognize Diverse HSV Antigens

Antigen-specific T_RM persist and protect against skin or female reproductive tract (FRT) HSV infection. As the pathogenesis of HSV differs between humans and model organisms, we focus on humans with well-characterized recurrent genital HSV-2 infection. Human CD8+ T_RM persisting at sites of healed human HSV-2 lesions have an activated phenotype but it is unclear if T_RM can be cultivated in vitro. We recovered HSV-specific T_RM from genital skin and ectocervix biopsies, obtained after recovery from recurrent genital HSV-2, using ex vivo activation by viral antigen. Up to several percent of local T cells were HSV-reactive ex vivo. CD4 and CD8 T cell lines were up to 50% HSV-2-specific after sorting-based enrichment. CD8 T_RM displayed HLA-restricted reactivity to specific HSV-2 peptides with high functional avidities. Reactivity to defined peptides persisted locally over several month and was quite subject-specific. CD4 T_RM derived from biopsies, and from an extended set of cervical cytobrush specimens, also recognized diverse HSV-2 antigens and peptides. Overall we found that HSV-2-specific T_RM are abundant in the FRT between episodes of recurrent genital herpes and maintain competency for expansion. Mucosal sites are accessible for clinical monitoring during immune interventions such as therapeutic vaccination.

Neonatal Herpes Simplex Virus Infection: Epidemiology and Outcomes in the Modern Era

BACKGROUND

Over the past several decades, there have been advances in diagnosis and treatment of neonatal herpes simplex virus (HSV) disease. There has been no recent comprehensive evaluation of the impact of these advances on the management and outcomes for neonates with HSV.

METHODS

Clinical data for initial presentation, treatment, and outcomes were abstracted from medical records of neonates with HSV treated at Seattle Children's Hospital between 1980 and 2016.

RESULTS

One hundred thirty infants with a diagnosis of neonatal HSV were identified. Between 1980 and 2016, high-dose acyclovir treatment for neonatal HSV infection increased from 0% to close to 95%, with subsequent decrease in overall HSV-related mortality from 20.9% to 5.6%. However, even among infants treated with high-dose acyclovir, mortality was 40.9% for infants with disseminated (DIS) disease, and only 55% of infants with central nervous system (CNS) disease were without obvious neurologic abnormalities at 24 months. Over the study period, the time between initial symptoms and diagnosis decreased. Skin recurrences were more common with HSV-2 than HSV-1 (80% vs 55%; P = .02) and in infants with lesions at initial diagnosis (76% vs 47%; P = .02).

CONCLUSION

Changes in the standard of care for management of neonatal HSV disease have led to improvements in timeliness of diagnosis and outcome but mortality in infants with DIS disease and neurologic morbidity in infants with CNS disease remain high. Future research should focus on prevention of perinatal infection and subsequent recurrences.

T cell response to intact SARS-CoV-2 includes coronavirus cross-reactive and variant-specific components

SARS-CoV-2 provokes a robust T cell response. Peptide-based studies exclude antigen processing and presentation biology, which may influence T cell detection studies. To focus on responses to whole virus and complex antigens, we used intact SARS-CoV-2 and full-length proteins with DCs to activate CD8 and CD4 T cells from convalescent people. T cell receptor (TCR) sequencing showed partial repertoire preservation after expansion. Resultant CD8 T cells recognize SARS-CoV-2-infected respiratory tract cells, and CD4 T cells detect inactivated whole viral antigen. Specificity scans with proteome-covering protein/peptide arrays show that CD8 T cells are oligospecific per subject and that CD4 T cell breadth is higher. Some CD4 T cell lines enriched using SARS-CoV-2 cross-recognize whole seasonal coronavirus (sCoV) antigens, with protein, peptide, and HLA restriction validation. Conversely, recognition of some epitopes is eliminated for SARS-CoV-2 variants, including spike (S) epitopes in the Alpha, Beta, Gamma, and Delta variant lineages.

Antimicrobial resistance including Extended Spectrum Beta Lactamases (ESBL) among E. coli isolated from kenyan children at hospital discharge

Background

Children who have been discharged from hospital in sub-Saharan Africa remain at substantial risk of mortality in the post-discharge period. Antimicrobial resistance (AMR) may be an important factor. We sought to determine the prevalence and risk factors associated with AMR in commensal Escherichia coli(E. coli) from Kenyan children at the time of discharge.

Methodology/Principle findings

Fecal samples were collected from 406 children aged 1–59 months in western Kenya at the time of discharge from hospital and cultured for E. coli. Susceptibility to ampicillin, ceftriaxone, cefotaxime, ceftazidime, cefoxitin, imipenem, ciprofloxacin, gentamicin, combined amoxicillin/clavulanic acid, trimethoprim-sulfamethoxazole, azithromycin, and chloramphenicol was determined by disc diffusion according to guidelines from the Clinical and Laboratory Standards Institute (CLSI). Poisson regression was used to determine associations between participant characteristics and the presence of extended-spectrum beta-lactamases (ESBL) producing E. coli. Non-susceptibility to ampicillin (95%), gentamicin (44%), ceftriaxone (46%), and the presence of ESBL (44%) was high. Receipt of antibiotics during the hospitalization was associated with the presence of ESBL (aPR = 2.23; 95% CI: 1.29–3.83) as was being hospitalized within the prior year (aPR = 1.32 [1.07–1.69]). Open defecation (aPR = 2.02; 95% CI: 1.39–2.94), having a toilet shared with other households (aPR = 1.49; 95% CI: 1.17–1.89), and being female (aPR = 1.42; 95% CI: 1.15–1.76) were associated with carriage of ESBL E. coli

Conclusions/Significance

AMR is common among isolates of E. coli from children at hospital discharge in Kenya, including nearly half having detectable ESBL.

Children who have been hospitalized in sub-Saharan Africa remain at a high risk of death and morbidity for at least 6 months following discharge. These children may harbor AMR in commensal bacteria following hospitalization, which may be associated with poor outcomes. There are limited data describing AMR and risk factors that are associated with AMR carriage at hospital discharge. In this cross-sectional study of Kenyan children under 5 years of age discharged from hospitals, we found AMR to be high. Children who received antibiotics in the hospital, had limited access to improved sanitation, and who were female had the highest prevalence of ESBL-producing E. coli.

Delayed mortality among solid organ transplant recipients hospitalized for COVID-19

INTRODUCTION

Most studies of solid organ transplant (SOT) recipients with COVID-19 focus on outcomes within one month of illness onset. Delayed mortality in SOT recipients hospitalized for COVID-19 has not been fully examined.

METHODS

We used data from a multicenter registry to calculate mortality by 90 days following initial SARS-CoV-2 detection in SOT recipients hospitalized for COVID-19 and developed multivariable Cox proportional-hazards models to compare risk factors for death by days 28 and 90.

RESULTS

Vital status at day 90 was available for 936 of 1117 (84%) SOT recipients hospitalized for COVID-19: 190 of 936 (20%) died by 28 days and an additional 56 of 246 deaths (23%) occurred between days 29 and 90. Factors associated with mortality by day 90 included: age > 65 years [aHR 1.8 (1.3-2.4), p =<0.001], lung transplant (vs. non-lung transplant) [aHR 1.5 (1.0-2.3), p=0.05], heart failure [aHR 1.9 (1.2-2.9), p=0.006], chronic lung disease [aHR 2.3 (1.5-3.6), p<0.001] and body mass index ≥ 30 kg/m 2 [aHR 1.5 (1.1-2.0), p=0.02]. These associations were similar for mortality by day 28. Compared to diagnosis during early 2020 (March 1-June 19, 2020), diagnosis during late 2020 (June 20-December 31, 2020) was associated with lower mortality by day 28 [aHR 0.7 (0.5-1.0, p=0.04] but not by day 90 [aHR 0.9 (0.7-1.3), p=0.61].

CONCLUSIONS

In SOT recipients hospitalized for COVID-19, >20% of deaths occurred between 28 and 90 days following SARS-CoV-2 diagnosis. Future investigations should consider extending follow-up duration to 90 days for more complete mortality assessment.

Self-Assessed Severity as a Determinant of Coronavirus Disease 2019 Symptom Specificity: A Longitudinal Cohort Study

Coronavirus disease 2019 symptom definitions rarely include symptom severity. We collected daily nasal swab samples and symptom diaries from contacts of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) case patients. Requiring ≥1 moderate or severe symptom reduced sensitivity to predict SARS-CoV-2 shedding from 60.0% (95% confidence interval [CI], 52.9%-66.7%) to 31.5% (95% CI, 25.7%- 38.0%) but increased specificity from 77.5% (95% CI, 75.3%-79.5%) to 93.8% (95% CI, 92.7%-94.8%).

Comparison of Racial, Ethnic, and Geographic Location Diversity of Participants Enrolled in Clinic-Based vs 2 Remote COVID-19 Clinical Trials

IMPORTANCE

Racial and ethnic diversity among study participants is associated with improved generalizability of clinical trial results and may address inequities in evidence that informs public health strategies. Novel strategies are needed for equitable access and recruitment of diverse clinical trial populations.

OBJECTIVE

To investigate demographic and geographical location data for participants in 2 remote COVID-19 clinical trials with online recruitment and compare with those of a contemporaneous clinic-based COVID-19 study.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study was conducted using data from 3 completed, prospective randomized clinical trials conducted at the same time: 2 remotely conducted studies (the Early Treatment Study and Hydroxychloroquine COVID-19 Postexposure Prophylaxis [PEP] Study) and 1 clinic-based study of convalescent plasma (the Expanded Access to Convalescent Plasma for the Treatment of Patients With COVID-19 study). Data were collected from March to August 2020 with 1 to 28 days of participant follow-up. All studies had clinical sites in Seattle, Washington; the 2 remote trials also had collaborating sites in New York, New York; Syracuse, New York; Baltimore, Maryland; Boston, Massachusetts; Chicago, Illinois; New Orleans, Louisiana; and Los Angeles, California. Two remote trials with inclusive social media strategies enrolled 929 participants with recent SARS-CoV-2 exposure (Hydroxychloroquine COVID-19 PEP Trial) and 231 participants with COVID-19 infection (Early Treatment Study); the clinic-based Expanded Access to Convalescent Plasma for the Treatment of Patients With COVID-19 study enrolled 250 participants with recent COVID-19 infection. Data were analyzed from April to August 2021.

INTERVENTIONS

Remote trials used inclusive social media strategies and clinician referral for recruitment and telehealth, courier deliveries, and self-collected nasal swabs for remotely conducted study visits. For the clinic-based study, participants were recruited via clinician referral and attended in-person visits.

MAIN OUTCOMES AND MEASURES

Google Analytics data were used to measure online participant engagement and recruitment. Participant demographics and geographical location data from remote trials were pooled and compared with those of the clinic-based study. Statistical comparison of demographic data was limited to participants with COVID infections (ie, those in the remotely conducted Early Treatment Study vs those in the clinic-based study) to improve accuracy of comparison given that the Hydroxychloroquine COVID-19 PEP Trial enrolled participants with COVID-19 exposures and thus had different enrollment criteria.

RESULTS

A total of 1410 participants were included. Among 1160 participants in remote trials and 250 participants in the clinic-based trial, the mean (range) age of participants was 39 (18-80) years vs 50 (19-79) years and 676 individuals (58.3%) vs 131 individuals (52.4%) reported female sex. The Early Treatment Study with inclusive social media strategies enrolled 231 participants in 41 US states with increased rates of racial, ethnic, and geographic diversity compared with participants in the clinic-based study. Among 228 participants in the remotely conducted Early Treatment Study with race data vs participants in the clinic-based study, 39 individuals (17.1%) vs 1 individual (0.4%) identified as Alaska Native or American Indian, 11 individuals (4.8%) vs 22 individuals (8.8%) identified as Asian, 26 individuals (11.4%) vs 4 individuals (1.6%) identified as Black, 3 individuals (1.3%) vs 1 individual identified as Native Hawaiian or Pacific Islander, 117 individuals (51.3%) vs 214 individuals (85.6%) identified as White, and 32 individuals (14.0%) vs 8 individuals (3.2%) identified as other race (P < .001). Among 230 individuals in the Early Treatment Study vs 236 individuals in the clinic-based trial with ethnicity data, 71 individuals (30.9%) vs 11 individuals (4.7%) identified as Hispanic or Latinx (P<.001). There were 29 individuals in the Early Treatment Study with nonurban residences (ie, rural, small town, or peri-urban; 12.6%) vs 6 of 248 individuals in the clinic-based trial with residence data (2.4%) (P < .001). In remote trial online recruitment, the highest engagement was with advertisements on social media platforms; among 125 147 unique users with age demographics who clicked on online recruitment advertisements, 84 188 individuals (67.3%) engaged via Facebook.

CONCLUSIONS AND RELEVANCE

These findings suggest that remote clinical trials with online advertising may be considered as a strategy to improve diversity among clinical trial participants.

T cell response to intact SARS-CoV-2 includes coronavirus cross-reactive and variant-specific components

SARS-CoV-2 provokes a brisk T cell response. Peptide-based studies exclude antigen processing and presentation biology and may influence T cell detection studies. To focus on responses to whole virus and complex antigens, we used intact SARS-CoV-2 and full-length proteins with DC to activate CD8 and CD4 T cells from convalescent persons. T cell receptor (TCR) sequencing showed partial repertoire preservation after expansion. Resultant CD8 T cells recognize SARS-CoV-2-infected respiratory cells, and CD4 T cells detect inactivated whole viral antigen. Specificity scans with proteome-covering protein/peptide arrays show that CD8 T cells are oligospecific per subject and that CD4 T cell breadth is higher. Some CD4 T cell lines enriched using SARS-CoV-2 cross-recognize whole seasonal coronavirus (sCoV) antigens, with protein, peptide, and HLA restriction validation. Conversely, recognition of some epitopes is eliminated for SARS-CoV-2 variants, including spike (S) epitopes in the alpha, beta, gamma, and delta variant lineages.

Trajectory of Viral RNA Load Among Persons With Incident SARS-CoV-2 G614 Infection (Wuhan Strain) in Association With COVID-19 Symptom Onset and Severity

IMPORTANCE

The SARS-CoV-2 viral trajectory has not been well characterized in incident infections. These data are needed to inform natural history, prevention practices, and therapeutic development.

OBJECTIVE

To characterize early SARS-CoV-2 viral RNA load (hereafter referred to as viral load) in individuals with incident infections in association with COVID-19 symptom onset and severity.

DESIGN, SETTING, AND PARTICIPANTS

This prospective cohort study was a secondary data analysis of a remotely conducted study that enrolled 829 asymptomatic community-based participants recently exposed (<96 hours) to persons with SARS-CoV-2 from 41 US states from March 31 to August 21, 2020. Two cohorts were studied: (1) participants who were SARS-CoV-2 negative at baseline and tested positive during study follow-up, and (2) participants who had 2 or more positive swabs during follow-up, regardless of the initial (baseline) swab result. Participants collected daily midturbinate swab samples for SARS-CoV-2 RNA detection and maintained symptom diaries for 14 days.

EXPOSURE

Laboratory-confirmed SARS-CoV-2 infection.

MAIN OUTCOMES AND MEASURES

The observed SARS-CoV-2 viral load among incident infections was summarized, and piecewise linear mixed-effects models were used to estimate the characteristics of viral trajectories in association with COVID-19 symptom onset and severity.

RESULTS

A total of 97 participants (55 women [57%]; median age, 37 years [IQR, 27-52 years]) developed incident infections during follow-up. Forty-two participants (43%) had viral shedding for 1 day (median peak viral load cycle threshold [Ct] value, 38.5 [95% CI, 38.3-39.0]), 18 (19%) for 2 to 6 days (median Ct value, 36.7 [95% CI, 30.2-38.1]), and 31 (32%) for 7 days or more (median Ct value, 18.3 [95% CI, 17.4-22.0]). The cycle threshold value has an inverse association with viral load. Six participants (6%) had 1 to 6 days of viral shedding with censored duration. The peak mean (SD) viral load was observed on day 3 of shedding (Ct value, 33.8 [95% CI, 31.9-35.6]). Based on the statistical models fitted to 129 participants (60 men [47%]; median age, 38 years [IQR, 25-54 years]) with 2 or more SARS-CoV-2-positive swab samples, persons reporting moderate or severe symptoms tended to have a higher peak mean viral load than those who were asymptomatic (Ct value, 23.3 [95% CI, 22.6-24.0] vs 30.7 [95% CI, 29.8-31.4]). Mild symptoms generally started within 1 day of peak viral load, and moderate or severe symptoms 2 days after peak viral load. All 535 sequenced samples detected the G614 variant (Wuhan strain).

CONCLUSIONS AND RELEVANCE

This cohort study suggests that having incident SARS-CoV-2 G614 infection was associated with a rapid viral load peak followed by slower decay. COVID-19 symptom onset generally coincided with peak viral load, which correlated positively with symptom severity. This longitudinal evaluation of the SARS-CoV-2 G614 with frequent molecular testing serves as a reference for comparing emergent viral lineages to inform clinical trial designs and public health strategies to contain the spread of the virus.

Awareness and Correlates of HIV Pre-Exposure Prophylaxis (PrEP) Among HIV-negative People Who Access Syringe Services in Seattle, Washington

BACKGROUND

HIV pre-exposure prophylaxis (PrEP) is safe and effective for use in people who inject drugs (PWID), but PrEP is underutilized in this population. We assessed awareness of PrEP and correlates of interest in PrEP among PWID in Seattle, Washington.

METHODS

This study analyzed data from a 2019 survey of PWID at 3 Seattle-area syringe service programs (SSPs). We used descriptive statistics to compare PrEP-aware and unaware PWID and multivariable Poisson regression with robust standard errors to estimate adjusted prevalence ratios (APR) for interest in PrEP.

RESULTS

Among 348 HIV-negative PWID, ≤1% were currently taking PrEP, 51% were PrEP aware and 46% were interested in PrEP. Interest in PrEP was inversely associated with prior PrEP awareness (APR 0.58, 95% CI 0.45 - 0.74); however, interest in PrEP was high among PWID meeting pre-specified risk criteria for HIV (APR 1.41, 95% CI 1.06 - 1.88).

CONCLUSIONS

Our results suggest increasing awareness of PrEP may not be sufficient to promote PrEP uptake among PWID, and further efforts are needed to understand perceptions of risk for HIV, determinants of PrEP use, and to investigate successful strategies for PrEP implementation and delivery in this marginalized population.

Supplemental data for this article is available online at https://doi.org/10.1080/10826084.2021.2012688 .

Cervical cancer screening, abnormal results, and follow-up in women with substance use-related diagnoses

Background: Substance use-related diagnoses are common and associated with poor health outcomes. The objective of this analysis was to compare rates of cervical cancer screening, screening abnormalities, and follow-up care in women with and without a substance use-related diagnosis seen for primary care between January 1, 2016 and December 31, 2019 in the University of Washington healthcare system. Methods: This study included women aged 21-65 years of age who had at least one outpatient visit between January 1, 2016 and December 31, 2019 within one of 45 primary care or women's health clinics in the academic healthcare system. Exposure status was defined using ICD10 codes for substance-use related diagnoses or no substance-use related diagnoses. Only first cervical cancer screening was included. Generalized linear models with a binomial family and log link were used to estimate risk ratios. Results: 3845 women had a substance use-related diagnosis and 89214 did not. Women with a substance use-related diagnosis were less likely to be screened for cervical cancer (44%, 1675/3845) compared to women without a substance use-related diagnosis (49%, 43338/89214; relative risk [RR] 0.90, 95% CI 0.86-0.93). Women with a substance use-related diagnosis were also more likely to have an abnormal screening result (18%, 304/1675) compared to women without a substance use-related diagnosis (10%, 4528/43338; RR 1.74, 95% CI 1.56-1.93). Follow-up for abnormal screens did not differ significantly between groups (24 vs 25%; RR 0.80, 95% CI 0.55-1.17). Conclusion: To combat disparities in cervical cancer screening for women with substance use-related diagnoses, public health efforts should expand access to screening where women with substance use-related diagnoses are seen, including acute care, inpatient hospitalizations, and addiction treatment settings.

Starting to have sexual intercourse is associated with increases in cervicovaginal immune mediators in young women: a prospective study and meta-analysis

Background:

Adolescent girls and young women (AGYW) are at high risk of sexually transmitted infections (STIs). It is unknown whether beginning to have sexual intercourse results in changes to immune mediators in the cervicovaginal tract that contribute to this risk.

Methods:

We collected cervicovaginal lavages from Kenyan AGYW in the months before and after first penile-vaginal sexual intercourse and measured the concentrations of 20 immune mediators. We compared concentrations pre- and post-first sex using mixed effect models. We additionally performed a systematic review to identify similar studies and combined them with our results by meta-analysis of individual participant data.

Results:

We included 180 samples from 95 AGYW, with 44% providing only pre-first sex samples, 35% matched pre and post, and 21% only post. We consistently detected 19/20 immune mediators, all of which increased post-first sex (p<0.05 for 13/19; Holm-Bonferroni-adjusted p<0.05 for IL-1β, IL-2, and CXCL8). Effects remained similar after excluding samples with STIs and high Nugent scores. Concentrations increased cumulatively over time after date of first sex, with an estimated doubling time of about 5 months.

Our systematic review identified two eligible studies, one of 93 Belgian participants, and the other of 18 American participants. Nine immune mediators were measured in at least two-thirds of studies. Meta-analysis confirmed higher levels post-first sex for 8/9 immune mediators (p<0.05 for six mediators, most prominently IL-1α, IL-1β, and CXCL8).

Conclusions:

Cervicovaginal immune mediator concentrations were higher in women who reported that they started sexual activity. Results were consistent across three studies conducted on three different continents.

Funding:

This research was funded by R01 HD091996-01 (ACR), by P01 AI 030731-25 (Project 1) (AW), R01 AI116292 (FH), R03 AI154366 (FH) and by the Center for AIDS Research (CFAR) of the University of Washington/Fred Hutchinson Cancer Research Center AI027757.

1060. Pritelivir in Immunocompromised Patients with Mucocutaneous Acyclovir-Resistant Herpes Simplex Virus-Infections – First Case Series

Background

HSV recurrences are usually managed effectively with existing antiviral drugs (nucleoside analogs such as acyclovir). However, in immunocompromised patients (e.g., malignancy, HIV, transplant), if lesions persist or recur while receiving antiviral treatment, acyclovir resistance should be suspected. In this population, there are limited treatment options. The helicase-primase inhibitor pritelivir is a novel oral antiviral, with a new mode of action and is active against both HSV-1 and HSV-2, including acyclovir and foscarnet-resistant strains. In this case series, we report the first clinical experiences with pritelivir in the treatment of immunocompromised patients with acyclovir resistant HSV infection.

Methods

All patient reported in this case series received pritelivir in a Phase 2 study. There were treated in an open-label design with a 400 mg pritelivir oral loading dose followed by a 100 mg oral maintenance dose daily for up to 28 days.

Results

Of the 23 patients, 11 had HIV infection and 12 had malignancy, transplant or an autoimmune disease. Of this cohort, 19 patients showed full resolution of their HSV-related lesions during the 28 day treatment period, while in 4 subjects lesions improved but did not completely heal during the observation period. Pritelivir was well tolerated without significant adverse effects.Reasons for incomplete lesion resolution during the 28 day treatment period, were extensive lesions in one patient, one patient with resistance development, and one patient with lesions in the oral cavity. Three patients subsequently experienced full resolution, while one patient required foscarnet due to CMV reactivation, necessitating early discontinuation.

Conclusion

Pritelivir is a promising novel treatment option for patients with severe mucocutaneous HSV-1/2 infections that are resistant to acyclovir and foscarnet. An international Phase 3 study is underway to evaluate pritelivir efficacy in immunocompromised patients.

Disclosures

Joerg Albrecht, MD/PhD, Biogen (Scientific Research Study Investigator)Investigator for AiCuris (Scientific Research Study Investigator) Robin K. Avery, MD, Aicuris (Grant/Research Support)Astellas (Grant/Research Support)Chimerix (Research Grant or Support)Merck (Grant/Research Support)Oxford Immunotec (Grant/Research Support)Qiagen (Grant/Research Support)Takeda/Shire (Grant/Research Support) Roy F. Chemaly, MD, MPH, FACP, FIDSA, AiCuris (Grant/Research Support)Ansun Biopharma (Consultant, Grant/Research Support)Chimerix (Consultant, Grant/Research Support)Clinigen (Consultant)Genentech (Consultant, Grant/Research Support)Janssen (Consultant, Grant/Research Support)Karius (Grant/Research Support)Merck (Consultant, Grant/Research Support)Molecular Partners (Consultant, Advisor or Review Panel member)Novartis (Grant/Research Support)Oxford Immunotec (Consultant, Grant/Research Support)Partner Therapeutics (Consultant)Pulmotec (Consultant, Grant/Research Support)Shire/Takeda (Consultant, Grant/Research Support)Viracor (Grant/Research Support)Xenex (Grant/Research Support) Nicolas C. Issa, MD, AiCuris (Scientific Research Study Investigator)Astellas (Scientific Research Study Investigator)GSK (Scientific Research Study Investigator)Merck (Scientific Research Study Investigator) Camille Kotton, MD, Shire/Takeda (Advisor or Review Panel member) Camille Kotton, MD, UpToDate (Individual(s) Involved: Self): I write chapters on zoonoses for UpToDate., Independent Contractor Princy N. Kumar, MD, AMGEN (Other Financial or Material Support, Honoraria)Eli Lilly (Grant/Research Support)Gilead (Grant/Research Support, Shareholder, Other Financial or Material Support, Honoraria)GSK (Grant/Research Support, Shareholder, Other Financial or Material Support, Honoraria)Merck & Co., Inc. (Grant/Research Support, Shareholder, Other Financial or Material Support, Honoraria) Moti Ramgopal, MD FACP FIDSA, Abbvie (Scientific Research Study Investigator, Speaker’s Bureau)Gilead (Consultant, Scientific Research Study Investigator, Speaker’s Bureau)Janssen (Consultant, Scientific Research Study Investigator, Research Grant or Support, Speaker’s Bureau)Merck (Consultant, Scientific Research Study Investigator)ViiV (Consultant, Scientific Research Study Investigator, Speaker’s Bureau) Anna Wald, MD, MPH, Aicuris (Consultant)Crozet (Consultant)GSK (Scientific Research Study Investigator)Merck (Other Financial or Material Support, DSMB)Sanofi (Scientific Research Study Investigator)X-Vax (Consultant) Michael G. Ison, MD, MS, Celltrion, Inc. (Consultant)

Cross-reactive and mono-reactive SARS-CoV-2 CD4+ T cells in prepandemic and COVID-19 convalescent individuals

Class II tetramer reagents for eleven common DR alleles and a DP allele prevalent in the world population were used to identify SARS-CoV-2 CD4+ T cell epitopes. A total of 112, 28 and 42 epitopes specific for Spike, Membrane and Nucleocapsid, respectively, with defined HLA-restriction were identified. Direct ex vivo staining of PBMC with tetramer reagents was used to define immunodominant and subdominant T cell epitopes and estimate the frequencies of these T cells in SARS-CoV-2 exposed and naïve individuals. Majority of SARS-CoV-2 epitopes identified have <67% amino acid sequence identity with endemic coronaviruses and are unlikely to elicit high avidity cross-reactive T cell responses. Four SARS-CoV-2 Spike reactive epitopes, including a DPB1*04:01 restricted epitope, with ≥67% amino acid sequence identity to endemic coronavirus were identified. SARS-CoV-2 T cell lines for three of these epitopes elicited cross-reactive T cell responses to endemic cold viruses. An endemic coronavirus Spike T cell line showed cross-reactivity to the fourth SARS-CoV-2 epitope. Three of the Spike cross-reactive epitopes were subdominant epitopes, while the DPB1*04:01 restricted epitope was a dominant epitope. Frequency analyses showed Spike cross-reactive T cells as detected by tetramers were present at relatively low frequency in unexposed people and only contributed a small proportion of the overall Spike-specific CD4+ T cells in COVID-19 convalescent individuals. In total, these results suggested a very limited number of SARS-CoV-2 T cells as detected by tetramers are capable of recognizing ccCoV with relative high avidity and vice versa. The potentially supportive role of these high avidity cross-reactive T cells in protective immunity against SARS-CoV-2 needs further studies.

Tissue-Resident-Memory CD8+ T Cells Bridge Innate Immune Responses in Neighboring Epithelial Cells to Control Human Genital Herpes

Tissue-resident-memory T cells (TRM) populate the body’s barrier surfaces, functioning as frontline responders against reencountered pathogens. Understanding of the mechanisms by which CD8TRM achieve effective immune protection remains incomplete in a naturally recurring human disease. Using laser capture microdissection and transcriptional profiling, we investigate the impact of CD8TRM on the tissue microenvironment in skin biopsies sequentially obtained from a clinical cohort of diverse disease expression during herpes simplex virus 2 (HSV-2) reactivation. Epithelial cells neighboring CD8TRM display elevated and widespread innate and cell-intrinsic antiviral signature expression, largely related to IFNG expression. Detailed evaluation via T-cell receptor reconstruction confirms that CD8TRM recognize viral-infected cells at the specific HSV-2 peptide/HLA level. The hierarchical pattern of core IFN-γ signature expression is well-conserved in normal human skin across various anatomic sites, while elevation of IFI16, TRIM 22, IFITM2, IFITM3, MX1, MX2, STAT1, IRF7, ISG15, IFI44, CXCL10 and CCL5 expression is associated with HSV-2-affected asymptomatic tissue. In primary human cells, IFN-γ pretreatment reduces gene transcription at the immediate-early stage of virus lifecycle, enhances IFI16 restriction of wild-type HSV-2 replication and renders favorable kinetics for host protection. Thus, the adaptive immune response through antigen-specific recognition instructs innate and cell-intrinsic antiviral machinery to control herpes reactivation, a reversal of the canonical thinking of innate activating adaptive immunity in primary infection. Communication from CD8TRM to surrounding epithelial cells to activate broad innate resistance might be critical in restraining various viral diseases.

Self-collection of capillary blood using Tasso-SST devices for Anti-SARS-CoV-2 IgG antibody testing

Background

Efforts to minimize COVID-19 exposure during the current SARS-CoV-2 pandemic have led to limitations in access to medical care and testing. The Tasso-SST kit includes all of the components necessary for remote, capillary blood self-collection. In this study, we sought to investigate the accuracy and reliability of the Tasso-SST device as a self-collection device for measurement of SARS-CoV-2 IgG antibodies.

Methods

Capillary blood was obtained via unsupervised and supervised application of the Tasso-SST device, and venous blood was collected by standard venipuncture. Unsupervised self-collected blood samples underwent either extreme summer or winter-simulated shipping conditions prior to testing. Sera obtained by all three methods were tested concurrently using the EuroImmun anti-SARS-CoV-2 S1 IgG assay in a CLIA-certified clinical laboratory.

Results

Successful Tasso-SST capillary blood collection by unsupervised and supervised administration was completed by 93.4% and 94.5% of participants, respectively. Sera from 56 participants, 55 with documented (PCR+) COVID-19, and 33 healthy controls were then tested for anti-SARS-CoV-2 IgG antibodies. Compared to venous blood results, Tasso-SST-collected (unstressed) and the summer- and winter-stressed blood samples demonstrated Deming regression slopes of 1.00 (95% CI: 0.99–1.02), 1.00 (95% CI: 0.98–1.01), and 0.99 (95% CI: 0.97–1.01), respectively, with an overall accuracy of 98.9%.

Conclusions

Capillary blood self-collection using the Tasso-SST device had a high success rate. Moreover, excellent concordance was found for anti-SARS-CoV-2 IgG results between Tasso-SST capillary and standard venous blood-derived sera. The Tasso-SST device should enable widespread collection of capillary blood for testing without medical supervision, facilitating epidemiologic studies.

Distinct populations of antigen-specific tissue-resident CD8+ T cells in human cervix mucosa

The ectocervix is part of the lower female reproductive tract (FRT), which is susceptible to sexually transmitted infections (STIs). Comprehensive knowledge of the phenotypes and T cell receptor (TCR) repertoire of tissue-resident memory T cells (TRMs) in the human FRT is lacking. We took single-cell RNA-Seq approaches to simultaneously define gene expression and TCR clonotypes of the human ectocervix. There were significantly more CD8+ than CD4+ T cells. Unsupervised clustering and trajectory analysis identified distinct populations of CD8+ T cells with IFNGhiGZMBloCD69hiCD103lo or IFNGloGZMBhiCD69medCD103hi phenotypes. Little overlap was seen between their TCR repertoires. Immunofluorescence staining showed that CD103+CD8+ TRMs were preferentially localized in the epithelium, whereas CD69+CD8+ TRMs were distributed evenly in the epithelium and stroma. Ex vivo assays indicated that up to 14% of cervical CD8+ TRM clonotypes were HSV-2 reactive in HSV-2-seropositive persons, reflecting physiologically relevant localization. Our studies identified subgroups of CD8+ TRMs in the human ectocervix that exhibited distinct expression of antiviral defense and tissue residency markers, anatomic locations, and TCR repertoires that target anatomically relevant viral antigens. Optimization of the location, number, and function of FRT TRMs is an important approach for improving host defenses to STIs.

Examining the dynamics of Epstein-Barr virus shedding in the tonsils and the impact of HIV-1 coinfection on daily saliva viral loads

Epstein-Barr virus (EBV) is transmitted by saliva and is a major cause of cancer, particularly in people living with HIV/AIDS. Here, we describe the frequency and quantity of EBV detection in the saliva of Ugandan adults with and without HIV-1 infection and use these data to develop a novel mathematical model of EBV infection in the tonsils. Eligible cohort participants were not taking antiviral medications, and those with HIV-1 infection had a CD4 count >200 cells/mm3. Over a 4-week period, participants provided daily oral swabs that we analysed for the presence and quantity of EBV. Compared with HIV-1 uninfected participants, HIV-1 coinfected participants had an increased risk of EBV detection in their saliva (IRR = 1.27, 95% CI = 1.10-1.47) and higher viral loads in positive samples. We used these data to develop a stochastic, mechanistic mathematical model that describes the dynamics of EBV, infected cells, and immune response within the tonsillar epithelium to analyse potential factors that may cause EBV infection to be more severe in HIV-1 coinfected participants. The model, fit using Approximate Bayesian Computation, showed high fidelity to daily oral shedding data and matched key summary statistics. When evaluating how model parameters differed among participants with and without HIV-1 coinfection, results suggest HIV-1 coinfected individuals have higher rates of B cell reactivation, which can seed new infection in the tonsils and lower rates of an EBV-specific immune response. Subsequently, both these traits may explain higher and more frequent EBV detection in the saliva of HIV-1 coinfected individuals.

B cells, antibody-secreting cells, and virus-specific antibodies respond to herpes simplex virus 2 reactivation in skin

Tissue-based T cells are important effectors in the prevention and control of mucosal viral infections; less is known about tissue-based B cells. We demonstrate that B cells and antibody-secreting cells (ASCs) are present in inflammatory infiltrates in skin biopsy specimens from study participants during symptomatic herpes simplex virus 2 (HSV-2) reactivation and early healing. Both CD20+ B cells, most of which are antigen inexperienced based on their coexpression of IgD, and ASCs - characterized by dense IgG RNA expression in combination with CD138, IRF4, and Blimp-1 RNA - were found to colocalize with T cells. ASCs clustered with CD4+ T cells, suggesting the potential for crosstalk. HSV-2-specific antibodies to virus surface antigens were also present in tissue and increased in concentration during HSV-2 reactivation and healing, unlike in serum, where concentrations remained static over time. B cells, ASCs, and HSV-specific antibody were rarely detected in biopsies of unaffected skin. Evaluation of samples from serial biopsies demonstrated that B cells and ASCs followed a more migratory than resident pattern of infiltration in HSV-affected genital skin, in contrast to T cells. Together, these observations suggest the presence of distinct phenotypes of B cells in HSV-affected tissue; dissecting their role in reactivation may reveal new therapeutic avenues to control these infections.

A Public Health COVID-19 Vaccination Strategy to Maximize the Health Gains for Every Single Vaccine Dose

This commentary discusses the pros and cons of single-dose COVID-19 vaccination versus the 2-dose strategy.