Increased platelet activation and lower platelet-monocyte aggregates in COVID-19 patients with severe pneumonia.

BACKGROUND: The increased procoagulant platelets and platelet activation are associated with thrombosis in COVID-19. In this study, we investigated platelet activation in COVID-19 patients and their association with other disease markers. METHODS: COVID-19 patients were classified into three severity groups: no pneumonia, mild-to-moderate pneumonia, and severe pneumonia. The expression of P-selectin and activated glycoprotein (aGP) IIb/IIIa on the platelet surface and platelet-leukocyte aggregates were measured prospectively on admission days 1, 7, and 10 by flow cytometry. RESULTS: P-selectin expression, platelet-neutrophil, platelet-lymphocyte, and platelet-monocyte aggregates were higher in COVID-19 patients than in uninfected control individuals. In contrast, aGPIIb/IIIa expression was not different between patients and controls. Severe pneumonia patients had lower platelet-monocyte aggregates than patients without pneumonia and patients with mild-to-moderate pneumonia. Platelet-neutrophil and platelet-lymphocyte aggregates were not different among groups. There was no change in platelet-leukocyte aggregates and P-selectin expression on days 1, 7, and 10. aGPIIb/IIIa expression was not different among patient groups. Still, adenosine diphosphate (ADP)-induced aGPIIb/IIIa expression was lower in severe pneumonia than in patients without and with mild-to-moderate pneumonia. Platelet-monocyte aggregates exhibited a weak positive correlation with lymphocyte count and weak negative correlations with interleukin-6, D-dimer, lactate dehydrogenase, and nitrite. CONCLUSION: COVID-19 patients have higher platelet-leukocyte aggregates and P-selectin expression than controls, indicating increased platelet activation. Compared within patient groups, platelet-monocyte aggregates were lower in severe pneumonia patients.

Immunogenicity of a fractional or full third dose of AZD1222 vaccine or BNT162b2 messenger RNA vaccine after two doses of CoronaVac vaccines against the Delta and Omicron variants.

OBJECTIVES: The study aimed to compare the immunogenicity and safety of fractional (half) third doses of heterologous COVID-19 vaccines (AZD1222 or BNT162b2) to full doses after the two-dose CoronaVac and when boosting after three different extended intervals. METHODS: At 60-<90, 90-<120, or 120-180 days intervals after the two-dose CoronaVac, participants were randomized to full-dose or half-dose AZD1222 or BNT162b2, followed up at day 28, 60, and 90. Vaccination-induced immune responses to Ancestral, Delta, and Omicron BA.1 strains were evaluated by antispike, pseudovirus, and microneutralization and T cell assays. Descriptive statistics and noninferiority cut-offs were reported as geometric mean concentration or titer and concentration or titer ratios comparing baseline to day 28 and day 90 and different intervals. RESULTS: No safety concerns were detected. All assays and intervals showed noninferior immunogenicity between full doses and half doses. However, full-dose vaccines and/or longer 120-180-day intervals substantially improved the immunogenicity (measured by antispike or measured by pseudotyped virus neutralizing titers 50; P <0.001). Seroconversion rates were over 90% against the SARS-CoV-2 strains by all assays. Immunogenicity waned more quickly with half doses than full doses but remained high against the Ancestral or Delta strains. Against Omicron, the day 28 immunogenicity increased with longer intervals than shorter intervals for full-dose vaccines. CONCLUSION: Immune responses after day 28 when boosting at longer intervals after the two-dose CoronaVac was optimal. Half doses met the noninferiority criteria compared with the full dose by all the immune assays assessed.

Detectable Duration of Viable SARS-CoV-2, Total and Subgenomic SARS-CoV-2 RNA in Noncritically Ill COVID-19 Patients: a Prospective Cohort Study.

Determination of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infectivity is important in guiding the infection control and differentiating between reinfection and persistent viral RNA. Although viral culture is the gold standard to determine viral infectivity, the method is not practical. We studied the kinetics of SARS-CoV-2 total RNAs and subgenomic RNAs (sgRNAs) and their potential role as surrogate markers of viral infectivity. The kinetics of SARS-CoV-2 sgRNAs compared to those of the culture and total RNA shedding in a prospective cohort of patients diagnosed with coronavirus disease 2019 (COVID-19) were investigated. A total of 260 nasopharyngeal swabs from 36 patients were collected every other day after entering the study until the day of viral total RNA clearance, as measured by reverse transcription PCR (RT-PCR). Time to cessation of viral shedding was in order from shortest to longest: by viral culture, sgRNA RT-PCR, and total RNA RT-PCR. The median time (interquartile range) to negativity of viral culture, subgenomic N transcript, and N gene were 7 (5 to 9), 11 (9 to 16), and 18 (13 to 21) days, respectively (P < 0.001). Further analysis identified the receipt of steroid as the factors associated with longer duration of viral infectivity (hazard ratio, 3.28; 95% confidence interval, 1.02 to 10.61; P = 0.047). We propose the potential role of the detection of SARS-CoV-2 subgenomic RNA as the surrogate marker of viral infectivity. Patients with negative subgenomic N RNA RT-PCR could be considered for ending isolation. IMPORTANCE Our study, combined with existing evidence, suggests the feasibility of the use of subgenomic RNA RT-PCR as a surrogate marker for SARS-CoV-2 infectivity. The kinetics of SARS-CoV-2 subgenomic RNA should be further investigated in immunocompromised patients.

Spontaneous tension hemothorax in a severe COVID-19 patient receiving ECMO therapy: The other side of COVID-19-associated coagulopathy.

As opposed to widely recognized Coronavirus Disease 2019 (COVID-19)-associated thrombotic events, the unusual but serious bleeding complications in COVID-19 patients are worth-mentioned. Here, we describe a 44-year-old man afflicted by COVID-19 pneumonia with acute respiratory distress syndrome (ARDS) and submassive pulmonary embolism. The patient's condition initially improved with the prescription of ECMO, tocilizumab, and hemoadsorption, however, he later developed spontaneous tension hemothorax, which is considered rare but devastating in the setting of COVID-19. While the exact pathogenesis of COVID-19-associated bleeding events remains poorly understood, we aim to highlight the other aspect of coagulation dysfunction potentially caused by COVID-19.

SARS-CoV-2 RT-PCR positivity of individuals subsequent to completing quarantine upon entry into a country during a transmission-free period.

BACKGROUND: During the current coronavirus disease 2019 (COVID-19) pandemic, many countries require travellers to undergo a reverse transcription-polymerase chain reaction (RT-PCR) testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) before travelling across borders. However, in persons having recovered from COVID-19, RT-PCR positivity can persist for an extended period. MATERIALS AND METHODS: We describe three cases who sought fit-to-fly certificates in Thailand during the period free of local transmission but were tested positive for RT-PCR for SARS-CoV-2. All had returned from a country with an active outbreak of COVID-19. Their clinical courses are described; positive nasopharyngeal swab samples were processed for viral isolation and whole-genome sequencing (WGS); and serology as well as neutralizing antibody were assessed. The contact tracing was carried out for determining evidence of indigenous transmission among close contacts of those three cases. RESULTS: All three cases were completely asymptomatic. Chest computerized tomography was not compatible with COVID-19 pneumonia; cell cultures failed to rescue replication-competent virus; WGS revealed fragmented viral genetic material from nasopharyngeal swab samples; and serological tests demonstrated stable levels of antibodies, together with the presence of neutralizing antibody, suggesting past infection with negligible transmission risk. Contact tracing identified no transmission in high-risk close contact individuals. CONCLUSION: RT-PCR positivity for SARS-CoV-2 might detect fragmented viral genome. Issuance of a travel certificate in these circumstances is problematic. Serology tests can help to define past infection. A practical acceptable set of guidelines for issuance of a COVID-19 safety travel certification is a necessity.

SARS-CoV-2 neutralizing antibodies decline over one year and patients with severe COVID-19 pneumonia display a unique cytokine profile.

OBJECTIVES: As coronavirus disease 2019 (COVID-19) rages on worldwide, there is an urgent need to characterize immune correlates of protection from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and to identify immune determinants of COVID-19 severity. METHODS: This study examined the longitudinal profiles of neutralizing antibody (NAb) titers in hospitalized COVID-19 patients clinically diagnosed with mild symptoms, pneumonia, or severe pneumonia, up to 12 months after illness onset, using live-virus neutralization. Multiplex, correlation, and network analyses were used to characterize serum-derived inflammatory cytokine profiles in all severity groups. RESULTS: Peak NAb titers correlated with disease severity, and NAb titers declined over the course of 12 months regardless of severity. Multiplex analyses revealed that IP-10, IL-6, IL-7, and VEGF-α were significantly elevated in severe pneumonia cases compared to those with mild symptoms and pneumonia cases. Correlation and network analyses further suggested that cytokine network formation was distinct in different COVID-19 severity groups. CONCLUSIONS: The study findings inform on the long-term kinetics of naturally acquired serological immunity against SARS-CoV-2 and highlight the importance of identifying key cytokine networks for potential therapeutic immunomodulation.

Mice Immunized with the Vaccine Candidate HexaPro Spike Produce Neutralizing Antibodies against SARS-CoV-2.

Updated and revised versions of COVID-19 vaccines are vital due to genetic variations of the SARS-CoV-2 spike antigen. Furthermore, vaccines that are safe, cost-effective, and logistic-friendly are critically needed for global equity, especially for middle- to low-income countries. Recombinant protein-based subunit vaccines against SARS-CoV-2 have been reported using the receptor-binding domain (RBD) and the prefusion spike trimers (S-2P). Recently, a new version of prefusion spike trimers, named HexaPro, has been shown to possess two RBD in the "up" conformation, due to its physical property, as opposed to just one exposed RBD found in S-2P. Importantly, this HexaPro spike antigen is more stable than S-2P, raising its feasibility for global logistics and supply chain. Here, we report that the spike protein HexaPro offers a promising candidate for the SARS-CoV-2 vaccine. Mice immunized by the recombinant HexaPro adjuvanted with aluminum hydroxide using a prime-boost regimen produced high-titer neutralizing antibodies for up to 56 days after initial immunization against live SARS-CoV-2 infection. Also, the level of neutralization activity is comparable to that of convalescence sera. Our results indicate that the HexaPro subunit vaccine confers neutralization activity in sera collected from mice receiving the prime-boost regimen.

The association between body mass index and severity of Coronavirus Disease 2019 (COVID-19): A cohort study.

OBJECTIVES: The coronavirus disease 2019 (COVID-19) has become a worst pandemic. The clinical characteristics vary from asymptomatic to fatal. This study aims to examine the association between body mass index (BMI) levels and the severity of COVID-19. METHODS AND STUDY DESIGN: A cohort study included 147 adult patients with confirmed COVID-19 were categorized into 4 groups by BMI levels on admission: <18.5 (underweight), 18.5-22.9 (normal weight), 23.0-24.9 (overweight), and ≥25.0 kg/m2 (obese). Rates of pneumonia, severe pneumonia, acute kidney injury (AKI), and ICU stay during hospitalization across BMI group was determined. Logistic regression analysis was used to determine the association between BMI and severe pneumonia. RESULTS: Of the totals, patients having a BMI <18.5, 18.5-22.9, 23.0-24.9, and ≥25.0 kg/m2 were 12.9%, 38.1%, 17.7%, and 31.3%, respectively. The rates of pneumonia and severe pneumonia tended to be higher in patients with higher BMI, whereas the rates of AKI and ICU stay were higher in patients with BMI <18.5 kg/m2 and ≥ 25 kg/m2, when compared to patients with normal BMI. After controlling for age, sex, diabetes, hypertension and dyslipidemia in the logistic regression analysis, having a BMI ≥25.0 kg/m2 was associated with higher risk of severe pneumonia (OR 4.73; 95% CI, 1.50-14.94; p = 0.003) compared to having a BMI 18.5-22.9 kg/m2. During admission, elevated hemoglobin and alanine aminotransferase levels on day 7 and 14 of illness were associated with higher BMI levels. In contrast, rising of serum creatinine levels was observed in underweight patients on days 12 and 14 of illness. CONCLUSIONS: Obesity in patients with COVID-19 was associated with severe pneumonia and adverse outcomes such as AKI, transaminitis and ICU stay. Underweight patients should be closely monitored for AKI. Further studies in body composition are warranted to explore the links between adiposity and COVID-19 pathogenesis.

Role of clinical pharmacists in telemonitoring for patients with Coronavirus Disease 2019 (COVID-19).

WHAT IS KNOWN AND OBJECTIVE: Clinical pharmacists actively participate in patient care via patients' medication use. Yet the setting of Coronavirus Disease 2019 (COVID-19) limits patient contact with healthcare personnel. We aimed to review the services provided and drug-related problems detected using telemonitoring methods to guide clinical pharmacists in providing service in treating COVID-19 patients. COMMENT: At a tertiary care hospital in Thailand, clinical pharmacists provided pharmaceutical care services for COVID-19 patients via telemonitoring using the hospital's computerized physician order entry system. The pharmacists were able to provide therapeutic drug monitoring services, especially for anticoagulants. Many patients were considered special populations, with individualized requirements for drug dosing. Some adverse drug reactions were observed. Drug-related problems were mostly related to medication use in critically ill patients. WHAT IS NEW AND CONCLUSION: Telemonitoring is a viable method for clinical pharmacists to provide pharmaceutical care and meet the challenges posed by treating patients with COVID-19.