The Association Between Stool Shedding of SARS-Cov-2 Microbiome Diversity and Intestinal Inflammation

Introduction: The transmission of the etiologic virus of COVID-19 (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]) is thought to occur mainly via respiratory droplets even though limited evidence has shown the virus can be found in feces and involve the gastrointestinal (GI) tract. The aim of this study was to assess if patients with COVID-19 present with fecal shedding of SARS-CoV-2, intestinal inflammation or changes in their microbiota. Method(s): This was a prospective cohort study that included outpatients that presented with symptoms of COVID-19 and were tested using a nasopharyngeal PCR test (NPT). Two cohorts were selected: one with a (1) NPT and a control group with a (-) NPT. Stool and a clinical data were collected at baseline and then, days 14, 28 and 42. SARS-CoV-2 viral loads were measured in stool using PCR and stool microbiome was analyzed using 16S rRNA gene sequencing (V3/V4 region). Fecal calprotectin levels were also measured on each sample and used as a surrogate marker of intestinal inflammation. Result(s): 101 patients were recruited (410 total samples). Of those, 55 had a (1) COVID-19 NPT. Most patients with a (1) COVID-19 NPT PCR had a detectable fecal viral load (71%). Among these patients, 23 (55%) had detectable viral stool loads only at baseline, 12 through day 14, 6 through day 28 and 1 through day 42. One patient had a (-) NPT but detectable SARS-CoV-2 in the baseline stool sample. Subjects with (1) NPT presented more commonly with myalgias (p=0.02), dysgeusia (p=0.019) and anosmia (p=0.03) when compared to those with (-) NPT but there were no differences in any other symptoms including GI manifestations.Within the group with a (1) NPT, those patient with detectable SARS-CoV-2 in the stool were younger but no differences were seen in demographic, symptoms, or fecal calprotectin levels (Table). There was no correlation between fecal SARS-CoV-2 loads and fecal calprotectin levels (rho: 0.007 [p=0.95]). Patients with a (1) NPT PCR had higher evenness when compared to those that tested (-) for a NPT PCR. However, no differences were seen in other alpha or beta diversity (Figures 1A and 1B, respectively). Conclusion(s): Even though intestinal viral shedding of SARS-CoV-2 in patients with COVID-19 is common, these patients do not present with evidence of inflammation of the GI tract, a significantly disrupted gut microbiome or a higher incidence of GI symptoms when compared to patients with respiratory symptoms and no COVID-19.

Interferon 1beta-1a ring prophylaxis to reduce household transmission of SARS-CoV-2

Introduction/Aim: Accumulating evidence indicates that an early, robust type 1 interferon (IFN) response to SARS-CoV-2 is critical for COVID-19 outcomes. Our objective was to examine the prophylactic potential of IFN treatment to limit viral transmission Methods: A cluster-randomised clinical trial was undertaken to determine effects of IFNbeta-1a treatment on SARS-CoV-2 household transmission (clinicaltrials.gov: NCT04552379). Index cases were identified from confirmed SARS-CoV-2 cases in Santiago, Chile, with 341 index cases and 831 household contacts enrolled. Households received 125 mug subcutaneous pegylated-IFNbeta-1a on days 1, 6, & 11 (172 households, 607 participants), or standard care (169 households, 565 participants). Primary outcomes included: (1) duration of viral shedding in infected cases (IC-INF), (2) transmission to treatment-eligible household contacts (EHC-ITT) at day 11. Result(s): Of 1172 individuals randomised, 53 individuals withdrew from the study (IFNbeta-1a = 35, SOC = 18). Eighty-two households (IFNbeta-1a = 36, SOC = 46) where the index case was SARS-CoV-2 negative on days 1 & 6, or with no SARS-CoV-2 negative contacts at recruitment, were excluded from exploratory analyses. Treatment with IFNbeta-1a: had no effect on duration of viral shedding in the IC-INF population (primary outcome 1), had no effect on transmission of SARS-CoV-2 at day 11 in the EHC-ITT population (primary outcome 2) but an effect was observed in a sensitivity analysis at day 6 (EHC-ITT: OR = 0.493, 95% CI = 0.256-0.949), reduced duration of hospitalisation in the IC-INF population and incidence of hospitalisation in per-protocol index cases (secondary outcome 3). In exploratory frequentist analysis, a significant effect of IFNbeta-1a treatment on SARS-CoV-2 transmission by day 11 (OR = 0.55, 95% CI = 0.36-0.99), and a Bayesian analysis identified a significant reduction in the odds of transmission (OR = -0.85, 95% credible interval = -1.59--0.16). Conclusion(s): Ring prophylaxis with IFNbeta-1a had no effect on duration of viral shedding but reduces the probability of SARS-CoV-2 transmission to uninfected, post-exposure contacts within a household.

IMMUNE STATUS AND SARS-CoV-2 VIRAL DYNAMICS

Background: Immunocompromised persons are disproportionately affected by severe SARS-CoV-2 infection, but immune compromise is heterogenous, which may impact viral dynamics. We hypothesized that higher degrees of compromised immunity are associated with higher viral shedding and slower viral clearance in the absence of COVID-19 therapeutics. Method(s): Participants enrolled in ACTIV-2/A5401, a platform trial for COVID-19 therapeutics in non-hospitalized adults within 10 days of symptom onset, received either an active treatment or placebo between 8/2020 and 7/2021. Participants were categorized based on the extent of immunosuppression into none, mild, moderate and severe categories at enrollment (day 0). Longitudinal anterior nasal (AN) and plasma SARS-CoV-2 levels were measured with a quantitative PCR assay. Regression models assessed associations between immunocompromise severity and viral levels (VL) at day 0, and longitudinally among those on placebo with quantifiable RNA at day 0. Multivariate analyses adjusted for demographics and symptom duration and vaccination status at day 0. Result(s): Immunocompromised (mild 383, moderate 159, severe 35) and immunocompetent (1956) participants had comparable symptom durations at day 0 (median 6 days) and most were unvaccinated (~95%). AN VL at day 0 was higher in the moderate/severe group compared to the immunocompetent group (adjusted difference in means: 0.47 log10 copies/mL, 95% CI 0.12, 0.83). While AN VL decayed at similar rates among all groups from day 0 to 3, there was a trend towards higher cumulative AN VLs across the 28-day follow-up in the moderate/severe group compared to immunocompetent group (adjusted fold difference in VL AUC 1.63, 95%CI 0.95, 2.77). The mild group showed no differences in day 0 VL or AUC compared to the immunocompetent group. The frequency of detectable plasma SARS-CoV-2 RNA was similar at day 0 across all groups (overall 21%), but there appeared to be a higher proportion of immunocompromised participants with detectable plasma viral RNA at day 7 (moderate/severe 2/23 [9%], mild 5/44 [11%]) compared to the immunocompetent group (8/282, 3%). Conclusion(s): Before emergence of Omicron and widespread vaccination, moderate/severe immunocompromised status was associated with higher nasal viral levels at study enrollment and showed a trend towards higher cumulative AN viral load, and all immunocompromised groups appeared to have more persistent plasma viremia during follow-up.

Prolonged Viable Viral Shedding in Immunocompromised Patients with Covid-19

Background: Immunocompromised patients with COVID-19 tend to shed viable virus for a prolonged period. Therefore, for moderately or severely immunocompromised patients with COVID-19, CDC recommends an isolation period of at least 20 days and ending isolation in conjunction with serial testing and consultation with an infectious disease specialist. However, data on viral kinetics and risk factors for prolonged viral shedding in these patients are limited. Method(s): From February 1, 2022 to April 1, 2022, we collected weekly saliva samples from immunocompromised patients with COVID-19 admitted to a tertiary hospital in Seoul, South Korea. Genomic and subgenomic RNAs were measured, and virus culture was performed. Result(s): A total of 41 patients were enrolled;29 (70%) were receiving chemotherapy against hematologic malignancies and the remaining 12 (30%) had undergone solid organ transplantation. Of the 41 patients, 14 (34%) had received 3 doses or more of COVID-19 vaccines. Real-time RT-PCR revealed that 7 (17%) were infected with Omicron BA.1, and 33 (80%) with Omicron BA.2. The median duration of viable virus shedding was 4 weeks (IQR 3-6). Patients undergoing B-cell depleting therapy shed viable virus for longer than the comparator (p=0.01). Multivariable analysis showed that 3-dose or more vaccination (HR 0.33, 95% CI 0.12 - 0.93, p = 0.04) and B-cell depleting therapy (HR 12.50, 95% CI 2.44 - 100.00, p = 0.003) independently affected viable virus shedding of SARS-CoV-2. Conclusion(s): Immunocompromised patients with COVID-19 shed viable virus for median 4 weeks. B-cell depleting therapy increases the risk of prolonged viable viral shedding, while completion of a primary vaccine series reduces this risk. Overall distribution of samples according to genomic viral copy number and culture positivity. Red dot indicates positive culture results, whereas blue dot indicated negative culture results. (Figure Presented).

Atypical Course of SarsCov-2 Infection in a Patient with Multiple Myeloma Treated with Autologous Stem Cell Transplantation

Covid-19 infection has more relevant consequences in frail and comorbid patients but little is known about its course in patients with hematologic malignancies. In this report we would like to present the case of a patient with multiple myeloma treated with recent autologous bone marrow stem cell transplantation and affected by Covid-19 pneumonia, presenting with a possible reinfection or an extremely long viral shedding.Copyright © 2023 Tehran University of Medical Sciences.

PROLONGED SARS-CoV-2 VIRAL BURDEN IN SIV-SARS-CoV-2 COINFECTED MACAQUES

Background: Individuals living with HIV are at increased risk of morbidity and mortality from COVID-19. Furthermore, SARS-CoV-2 infection in immunocompromised HIV infected individuals poses a risk to prolonged infection and viral shedding and the emergence of new variants of concern (VOCs). Using the SIV macaque model for AIDS, we are investigating the hypothesis that immune dysfunction during HIV infection will prolong SARSCoV- 2 viral infection, promote enhanced COVID-19 disease, and accelerate viral evolution. Here, we report the impact of SIV-CoV-2 co-infection on immune responses and pathogenesis. Method(s): Eight female rhesus macaques (aged 7-15 years, 5.5-9.9kg) were infected with SIVmac251 via low dose intravaginal challenge and then inoculated with 6.5x105 TCID50/mL SARS-CoV-2 (WA-1) at 17-34 weeks post-SIV infection via combined intranasal and intratracheal routes. Blood, bronchoalveolar lavage (BAL), stool, and nasal, oral, and rectal swabs were collected pre-infection through 14 days post-infection (DPI) to measure immune responses and viremia. ELISAs, ELISPOT, qRT-PCR, lung pathology, cytokine multiplex, and virus neutralization assays were performed to measure viral loads, pathogenesis, and immune responses. Result(s): Three days post-SARS-CoV-2 infection, we observed a transient decrease in CD4 counts, but there were no changes in clinical symptoms or plasma SIV viral loads. However, SARS-CoV-2 replication persisted in the upper respiratory tract, but not the lower respiratory tract. In addition, SARS-CoV-2 IgG seroconversion was delayed and antigen-specific T-cell responses were dampened. Notably, viral RNA levels in nasal swabs were significantly higher 7-14 DPI in SIV+ compared to previously published results using the same SARS-CoV-2 challenge virus in SIV- rhesus (PMCID: PMC8462335, PMC8829873). In addition, SIV/CoV-2 co-infected animals exhibited elevated levels of myeloperoxidase (MPO), a marker of neutrophil activation and increased lung inflammation. Conclusion(s): Here we provide evidence for the utility of the rhesus macaque in modeling human HIV-SARS-CoV-2 co-infection. Our results suggest that immunosuppression during SIV infection impairs de novo generation of anti-SARS-CoV-2 immunity, that may contribute to prolonged SARS-CoV-2 viral shedding, increased transmission windows, altered disease pathogenesis, and lower protection against subsequent SARS-CoV-2 exposures. Studies in progress will determine if SARS-CoV-2 viral evolution is accelerated in SIV-infected macaques.

NILMATREVIR-RITONAVIR TREATMENT IN CHILDREN WITH SARS-CoV-2 INFECTION

Background: Children seem to experience a less severe form of COVID-19 disease than adults, nevertheless, cases of severe infection have been described in a small proportion of patients, requiring hospitalization in 5-10% of cases. Among COVID-19 deaths 0,4% occurred in children and adolescents under 20 years of age. Most hospitalized children with acute COVID-19 had underlying conditions. Moreover, some children with previous COVID-19 infection, may later develop Multisystem Inflammatory Syndrome in Children (MIS-C), a rare but serious condition associated with COVID-19. These data suggest that a specific therapy is necessary in high-risk pediatric population, in order to prevent severe COVID-19, especially in children with underlying conditions. Antiviral paediatric data are currently very few Methods: We conducted a retrospective study on patients < 18 years of age who received Paxlovid (nirmatrelvir-ritonavir) for the treatment of mild-tomoderate COVID-19 at Bambino Gesu Children's Hospital from April 2022 to September 2022. Patients at high risk of progression to severe COVID-19 who had no need of supplemental oxygen received Paxlovid according to AIFA's indications for adults with the Informed Consent of relatives Results: 40 patients aged 1-18 years with confirmed SARS-CoV-2 infection were treated with Paxlovid (Tab 1)The average symptom duration was 4.2 days. No patient developed severe COVID-19 r All patients were treated within 5 days of symptom onset, Four patients received a longer course treatment (10 days) due to the persistence of symptoms combined with the presence of severe comorbidities .The mean time of viral shedding was 12.7 days, with a patient being persistently positive for 56 days. After Paxlovid initiation, only 5 patients (12.5%) experienced adverse reactions: Conclusion(s): Treatment with Paxlovid has proven to be safe. Further pharmacokinetic studies are required species for children < 5 years old.

Early antiviral therapy of abidol combined with lopinavir/ritonavir and recombinant interferon alpha-2b for patients with COVID-19 in Zhejiang: A multicenter prospective study.

Objective: To compare the efficacy of the combination of abidol, lopinavir/ritonavir plus recombinant interferon alpha-2b (rIFNalpha-2b) and the combination of lopinavir/ritonavir plus rIFNalpha-2b for patients with COVID-19 in Zhejiang province. Method(s): A multicenter prospective study was carried out to compare the efficacy of triple combination antiviral therapy and dual combination antiviral therapy in 15 medical institutions of Zhejiang province during January 22 to February 16, 2020. All patients were treated with rIFNalpha-2b (5 million U, 2 times/d) aerosol inhalation, in addition 196 patients were treated with abidol (200 mg, 3 times/d) + lopinavir/ritonavir (2 tablets, 1 time/12 h) (triple combination group) and 41 patients were treated with lopinavir/ritonavir (2 tablets, 1 time/12 h) (dual combination group). The patients who received triple combination antiviral therapy were further divided into three subgroups: <48 h, 3-5 d and >5 d according the time from the symptom onset to medication starting. The therapeutic efficacy was compared between triple combination group and dual combination group, and compared among 3 subgroups of patients receiving triple combination antiviral therapy. SPSS 17.0 software was used to analyze the data. Result(s): The virus nucleic acid-negative conversion time in respiratory tract specimens was (12.2+/-4.7) d in the triple combination group, which was shorter than that in the dual combination group [(15.0+/-5.0) d] (t=6.159, P<0.01). The length of hospital stay in the triple combination group [12.0 (9.0, 17.0) d] was also shorter than that in the dual combination group [15.0 (10.0, 18.0) d] (H=2.073, P<0.05). Compared with the antiviral treatment which was started within after the symptom onset of in the triple combination group, the time from the symptom onset to the viral negative conversion was 13.0 (10.0, 17.0), 17.0 (13.0, 22.0) and 21.0 (18.0, 24.0) d in subgroups of 48 h, 3-5 d and >5 d, respectively (Z=32.983, P<0.01), while the time from antiviral therapy to viral negative conversion was (11.8+/-3.9), (13.5+/-5.1) and (11.2+/-4.3) d, respectively(Z=6.722, P<0.05). Conclusion(s): The triple combination antiviral therapy of abidol, lopinavir/litonavir and rIFNalpha-2b shows shorter viral shedding time and shorter hospitalization time, compared with the dual combination antiviral therapy;and the earlier starting triple combination antiviral therapy will result in better antiviral efficacy.Copyright © 2020 by the Chinese Medical Association.

Food safety concerns in "COVID-19 era"

In March 2020, the World Health Organization (WHO) declared that the COVID-19 outbreak can be characterized as a pandemic. Human-to-human transmission of the SARS-CoV-2 virus may initially be blamed as the first cause of spread, but can an infection be contracted by ingestion of contaminated food or touching contaminated food surfaces? Recently cold-chain food contamination has been indicated as a possible source of many human cases in China. However, the risk of a food-related COVID-19 infection is still debated since the virus may reach people through a fresh product or packaging, which have been touched/sneezed on by infected people. This review summarizes the most recent evidence on the zoonotic origin of the pandemic, reports the main results regarding the transmission of SARS-CoV-2 through food or a food chain, as well as the persistence of the virus at different environmental conditions and surfaces. Emphasis is also posed on how to manage the risk of food-related COVID-19 spread and potential approaches that can reduce the risk of SARS-CoV-2 contamination.Copyright © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

Analysis of factors influencing viral shedding time in elderly patients with mild and asymptomatic Omicron infection.

Objective To analyze the potential factors influencing the viral shedding time (duration of nucleic acid positivity) in elderly patients with mild and asymptomatic infection. Methods The clinical data of 1141 elderly (>=60 years) patients with mild and asymptomatic Omicron infection who were admitted to National Exhibition and Convention Center (Shanghai) Cabin Hospital from April 14, 2022 to May 1, 2022 were retrospectively collected, viral shedding time of patients were compared between different groups (age, gender, number of vaccination, hypertension, diabetes). Pearson analysis was adopted to analyze the relationship between age and viral shedding time. Kaplan-Meier curve and Log-rank test were used to evaluate the viral shedding time in elderly patients with different clinical characteristics. Multivariate Cox proportional-hazards regression model was adopted to analyze the factors influencing viral shedding time in elderly patients with Omicron. Results Among 1441 patients, 791(54.9%) males and 650(45.1%) females. There were 513(35.6%) patients receiving 0 dose of vaccine, 29(2.0%) patients received 1 dose of vaccine, 405(28.1%) patients received 2 doses of vaccine, 494(34.3%) patients received 3 doses of vaccine. Compared with patients aged 60 to 70 years, patients aged 70 to 80 years had longer viral shedding time (P<0.001). The viral shedding time in patients with hypertension and diabetes was longer than that in patients without hypertension and diabetes (P<0.05). In terms of vaccination, the viral shedding time of patients receiving 2 or 3 doses of vaccine was significantly shorter than that of patients receiving 1 dose of vaccine or none (P<0.05). There was a positive correlation between patient age and viral shedding time, with an R2=0.029 (P<0.001). Kaplan-Meier curve showed that there existed significant difference in viral shedding time between the patients with different vaccination doses (P<0.001), and patients with age >=70, hypertension and diabetes were all associated with prolonged viral shedding time (P<0.05). Cox regression analysis showed that the age >=70 years was a risk factor for prolonged viral shedding time, and 2 or 3 doses of vaccine was a protective factor for prolonged viral shedding time (P<0.05). Conclusions Among the elderly population, the viral shedding time would gradually increase with age. Patients who received >=2 doses of vaccine would have reduced viral shedding time compared with those who received <2 doses of vaccine.Copyright © 2022 Authors. All rights reserved.

Progress and challenge for asymptomatic infection of 2019-nCoV.

By April 28, 2020, the global pandemic of COVID-19 has resulted in over 3 million infections and more than 200, 000 deaths. As the epidemic of COVID-19 has been basically controlled in China, the asymptomatic infection becomes one of most serious challenges for "External defense input, internal defense rebound" currently. Studies have shown that patients with asymptomatic infections are highly contagious in the early stage, most of whom are in the pre-symptomatic stage. Children and pregnant women have a higher incidence of asymptomatic infections, but the impacts are not yet clear. This article reviews the definition, epidemiological characteristics, contagiousness, viral shedding and cause of persistent positive nucleic acid in asymptomatic patients. Active detection of nucleic acids and antibodies and timely diagnosis and treatment of asymptomatic cases are the critical issues for the prevention and control of COVID-19.Copyright © 2020 by the Chinese Medical Association.

Progress and challenge for asymptomatic infection of 2019-nCoV.

By April 28, 2020, the global pandemic of COVID-19 has resulted in over 3 million infections and more than 200, 000 deaths. As the epidemic of COVID-19 has been basically controlled in China, the asymptomatic infection becomes one of most serious challenges for "External defense input, internal defense rebound" currently. Studies have shown that patients with asymptomatic infections are highly contagious in the early stage, most of whom are in the pre-symptomatic stage. Children and pregnant women have a higher incidence of asymptomatic infections, but the impacts are not yet clear. This article reviews the definition, epidemiological characteristics, contagiousness, viral shedding and cause of persistent positive nucleic acid in asymptomatic patients. Active detection of nucleic acids and antibodies and timely diagnosis and treatment of asymptomatic cases are the critical issues for the prevention and control of COVID-19.Copyright © 2020 by the Chinese Medical Association.

Progress and challenge for asymptomatic infection of 2019-nCoV.

By April 28, 2020, the global pandemic of COVID-19 has resulted in over 3 million infections and more than 200, 000 deaths. As the epidemic of COVID-19 has been basically controlled in China, the asymptomatic infection becomes one of most serious challenges for "External defense input, internal defense rebound" currently. Studies have shown that patients with asymptomatic infections are highly contagious in the early stage, most of whom are in the pre-symptomatic stage. Children and pregnant women have a higher incidence of asymptomatic infections, but the impacts are not yet clear. This article reviews the definition, epidemiological characteristics, contagiousness, viral shedding and cause of persistent positive nucleic acid in asymptomatic patients. Active detection of nucleic acids and antibodies and timely diagnosis and treatment of asymptomatic cases are the critical issues for the prevention and control of COVID-19.Copyright © 2020 by the Chinese Medical Association.

Duration of viable virus shedding and polymerase chain reaction positivity of the SARS-CoV-2 Omicron variant in the upper respiratory tract: a systematic review and meta-analysis.

OBJECTIVES: To assess the duration of viable virus shedding and polymerase chain reaction (PCR) positivity of the SARS-CoV-2 Omicron variant in the upper respiratory tract. METHODS: We systematically searched PubMed, Cochrane, and Web of Science for original articles reporting the duration of viable virus shedding and PCR positivity of the SARS-CoV-2 Omicron variant in the upper respiratory tract from November 11, 2021 to December 11, 2022. This meta-analysis was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and was registered with PROSPERO (CRD42022357349). We used the DerSimonian-Laird random-effects meta-analyses to obtain the pooled value and the 95% confidence intervals. RESULTS: We included 29 studies and 230,227 patients. The pooled duration of viable virus shedding of the SARS-CoV-2 Omicron variant in the upper respiratory tract was 5.16 days (95% CI: 4.18-6.14), and the average duration of PCR positivity was 10.82 days (95% CI: 10.23-11.42). The duration of viable virus shedding and PCR positivity of the SARS-CoV-2 Omicron variant in symptomatic patients was slightly higher than that in asymptomatic patients, but the difference was not significant (P >0.05). CONCLUSION: The current study improves our understanding of the status of the literature on the duration of viable virus shedding and PCR positivity of Omicron in the upper respiratory tract. Our findings have implications for pandemic control strategies and infection control measures.

Comparison of culture-competent virus shedding duration of SARS-CoV-2 Omicron variant in regard to vaccination status: A prospective cohort study.

Previous studies have shown that fully vaccinated patients with SARS-CoV-2 Delta variants has shorter viable viral shedding period compared to unvaccinated or partially vaccinated patients. However, data about effects of vaccination against the viable viral shedding period in patients with SARS-CoV-2 Omicron variants were limited. We compared the viable viral shedding period of SARS-CoV-2 omicron variant regard to vaccination status. Saliva samples were obtained daily from patients with SARS-CoV-2 Omicron variant, and genomic assessments and virus culture was performed to those samples. We found no difference in viable viral shedding period between fully vaccinated and not or partially vaccinated, nor between 1st boostered vs non-boostered patients with SARS-CoV-2 Omicron variant.

Transmission potential of vaccinated and unvaccinated persons infected with the SARS-CoV-2 Delta variant in a federal prison, July-August 2021.

BACKGROUND: The extent to which vaccinated persons who become infected with SARS-CoV-2 contribute to transmission is unclear. During a SARS-CoV-2 Delta variant outbreak among incarcerated persons with high vaccination rates in a federal prison, we assessed markers of viral shedding in vaccinated and unvaccinated persons. METHODS: Consenting incarcerated persons with confirmed SARS-CoV-2 infection provided mid-turbinate nasal specimens daily for 10 consecutive days and reported symptom data via questionnaire. Real-time reverse transcription-polymerase chain reaction (RT-PCR), viral whole genome sequencing, and viral culture was performed on these nasal specimens. Duration of RT-PCR positivity and viral culture positivity was assessed using survival analysis. RESULTS: A total of 957 specimens were provided by 93 participants, of whom 78 (84 %) were vaccinated and 17 (16 %) were unvaccinated. No significant differences were detected in duration of RT-PCR positivity among vaccinated participants (median: 13 days) versus those unvaccinated (median: 13 days; p = 0.50), or in duration of culture positivity (medians: 5 days and 5 days; p = 0.29). Among vaccinated participants, overall duration of culture positivity was shorter among Moderna vaccine recipients versus Pfizer (p = 0.048) or Janssen (p = 0.003) vaccine recipients. In post-hoc analyses, Moderna vaccine recipients demonstrated significantly shorter duration of culture positivity compared to unvaccinated participants (p = 0.02). When restricted to participants without reported prior infection, the difference between Moderna vaccine recipients and unvaccinated participants was more pronounced (medians: 3 days and 6 days, p = 0.002). CONCLUSIONS: Infectious periods for vaccinated and unvaccinated persons who become infected with SARS-CoV-2 are similar and can be highly variable, though some vaccinated persons are likely infectious for shorter durations. These findings are critically important, especially in congregate settings where viral transmission can lead to large outbreaks. In such settings, clinicians and public health practitioners should consider vaccinated, infected persons to be no less infectious than unvaccinated, infected persons.

Trajectories of the SARS-CoV-2 RNA load in patients with hematological malignancy.

OBJECTIVES: The higher risk of prolonged viral shedding in coronavirus disease (COVID-19) patients with hematological malignancies (HM) necessitates test-based de-isolation strategies. However, evidence to establish their appropriate isolation period is insufficient. This study investigated the factors affecting prolonged viral shedding and the requisite isolation period in these patients. METHODS: We retrospectively reviewed 14 COVID-19 patients with HM between January and April 2022, who were subjected to our test-based de-isolation strategy, followed by analysis of the viral load trajectory. The viral loads of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were evaluated using the cycle threshold (Ct ) of the reverse-transcription quantitative polymerase chain reaction. The trajectories were classified according to the time-interval from COVID-19 onset to the attainment of Ct values >30. RESULTS: The median interval between onset and attainment of a Ct value >30 was 22 days. Five patients with mild or moderate COVID-19 without intense treatment histories achieved Ct values >30 within 20 days. The other nine patients needed more than 20 days, including three patients who did not meet this criterion during the observation period. CONCLUSIONS: The SARS-CoV-2 viral load trajectories in patients with HM can be stratified by treatment history for the underlying HM and severity of COVID-19.

SARS-CoV-2 viral shedding in vaccinated and unvaccinated persons: A case series.

The preclinical time course of SARS-CoV-2 shedding is not well-described. Understanding this time course will help to inform risk of SARS-CoV-2 transmission. During an outbreak in a congregate setting, we collected paired mid-turbinate nasal swabs for antigen testing and reverse-transcription polymerase chain reaction (RT-PCR) every other day from all consenting infected and exposed persons. Among 12 persons tested prospectively before and during SARS-CoV-2 infection, ten of 12 participants (83%) had completed a primary COVID-19 vaccination series prior to the outbreak. We recovered SARS-CoV-2 in viral culture from 9/12 (75%) of participants. All three persons from whom we did not recover SARS-CoV-2 in viral culture had completed their primary vaccination series. We recovered SARS-CoV-2 from viral culture in 6/9 vaccinated persons and before symptom onset in 3/6 symptomatic persons. These findings underscore the need for both non-pharmaceutical interventions and vaccination to mitigate transmission.