Severity of the first 207 infections with the SARS-CoV-2 Omicron BA.2 variant, in Marseille, France, December, 2021-February, 2022

Characteristics and outcomes of COVID-19 patients presumed to be treated with sotrovimab in NHS hospitals in England

BACKGROUND

The impact of the constantly evolving severe acute respiratory syndrome coronavirus 2 on the effectiveness of early coronavirus disease 2019 (COVID-19) treatments is unclear. Here, we report characteristics and acute clinical outcomes of patients with COVID-19 treated with a monoclonal antibody (mAb; presumed to be sotrovimab) across six distinct periods covering the emergence and predominance of Omicron subvariants (BA.1, BA.2, and BA.5) in England.

METHODS

Retrospective cohort study using data from the Hospital Episode Statistics database from January 1-July 31, 2022. Included patients received a mAb delivered by a National Health Service (NHS) hospital as a day-case, for which the primary diagnosis was COVID-19. Patients were presumed to have received sotrovimab based on NHS data showing that 99.98% of COVID-19-mAb-treated individuals received sotrovimab during the study period. COVID-19-attributable hospitalizations were reported overall and across six distinct periods of Omicron subvariant prevalence. Subgroup analyses were conducted in patients with severe renal disease and active cancer.

RESULTS

Among a total of 10,096 patients, 1.0% (n = 96) had a COVID-19-attributable hospitalization, 4.6% (n = 465) had a hospital visit due to any cause, and 0.3% (n = 27) died due to any cause during the acute period. COVID-19-attributable hospitalization rates were consistent among subgroups, and no significant differences were observed across periods of Omicron subvariant predominance.

CONCLUSIONS

Levels of COVID-19-attributable hospitalizations and deaths were low in mAb-treated patients and among subgroups. Similar hospitalization rates were observed whilst Omicron BA.1, BA.2, and BA.5 were predominant, despite reported reductions in in vitro neutralization activity of sotrovimab against BA.2 and BA.5.

SARS-CoV-2 Viral Replication Persists in the Human Lung for Several Weeks after Symptom Onset

Rationale: In the upper respiratory tract, replicating (culturable) severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is recoverable for ∼4-8 days after symptom onset, but there is a paucity of data about the frequency and duration of replicating virus in the lower respiratory tract (i.e., the human lung).Objectives: We undertook lung tissue sampling (needle biopsy) shortly after death in 42 mechanically ventilated decedents during the Beta and Delta waves. An independent group of 18 ambulatory patients served as a control group.Methods: Lung biopsy cores from decedents underwent viral culture, histopathological analysis, electron microscopy, transcriptomic profiling, and immunohistochemistry.Measurements and Main Results: Thirty-eight percent (16 of 42) of mechanically ventilated decedents had culturable virus in the lung for a median of 15 days (persisting for up to 4 wk) after symptom onset. Lung viral culture positivity was not associated with comorbidities or steroid use. Delta but not Beta variant lung culture positivity was associated with accelerated death and secondary bacterial infection (P < 0.05). Nasopharyngeal culture was negative in 23.1% (6 of 26) of decedents despite lung culture positivity. This hitherto undescribed biophenotype of lung-specific persisting viral replication was associated with an enhanced transcriptomic pulmonary proinflammatory response but with concurrent viral culture positivity.Conclusions: Concurrent rather than sequential active viral replication continues to drive a heightened proinflammatory response in the human lung beyond the second week of illness and was associated with variant-specific increased mortality and morbidity. These findings have potential implications for the design of interventional strategies and clinical management of patients with severe coronavirus disease (COVID-19).

Pre-Hospital Management of Patients with COVID-19 and the Impact on Hospitalization

Background and Objectives: During the COVID-19 pandemic, patient care was mainly organized around the hospital. Pre-hospital care has, to our knowledge, never been evaluated. We aimed to study the impact of pre-hospital pathways on hospitalization during the last part of the pandemic. Materials and Methods: This was a monocentric, retrospective analysis of prospectively collected medical records. Data from patients admitted to our institute between 1 February and 7 March 2022 were analyzed. The primary outcomes were defined as the number of hospitalizations, resuscitations, and deaths at the time of interview and in the subsequent 30 days. The main explanatory variables were times from onset of symptoms to care, age, gender, News2 score, comorbidities, and pre-hospital pathways and their duration. Results: Three pre-hospital pathways were identified: a pathway in which the patient consults a general practitioner for a test (PHP1); a pathway in which the patient consults for care (PHP2); and no pre-hospital pathway and direct admission to hospital (PHP3). Factors independently associated with outcome (hospitalization) were being male (OR 95% CI; 2.21 (1.01-4.84), p = 0,04), News2 score (OR 95% CI; 2.04 (1.65-2.51), p < 0.001), obesity (OR 95% CI; 3.45 (1.48-8.09), p = 0.005), D-dimers > 0.5 µg/mL (OR 95% CI; 3.45 (1.47-8.12), p = 0.005), and prolonged time from symptoms to hospital care (PHP duration) (OR 95% CI; 1.07 (1.01-1.14), p = 0.03). All things being equal, patients with a "PHP2" pre-hospital pathway had a higher probability of hospitalization compared to those with a "PHP3" pre-hospital pathway (OR 95% CI; 4.31 (1.48-12.55), p = 0.007). Conclusions: Along with recognized risk factors such as gender, News 2 score, and obesity, the patient's pre-hospital pathway is an important risk factor associated with hospitalization.

Severity and outcomes of Omicron variant of SARS-CoV-2 compared to Delta variant and severity of Omicron sublineages: a systematic review and metanalysis

OBJECTIVES

To compare severity and clinical outcomes from Omicron as compared with the Delta variant and to compare outcomes between Omicron sublineages.

METHODS

We searched the WHO COVID-19 Research database for studies that compared clinical outcomes for patients with Omicron variant and the Delta variant, and separately Omicron sublineages BA.1 and BA.2. A random-effects meta-analysis was used to pool estimates of relative risk (RR) between variants and sublineages. Heterogeneity between studies was assessed using the I2 index. Risk of bias was assessed using the tool developed by the Clinical Advances through Research and Information Translation team.

RESULTS

Our search identified 1494 studies and 42 met the inclusion criteria. Eleven studies were published as preprints. Of the 42 studies, 29 adjusted for vaccination status; 12 had no adjustment; and for 1, the adjustment was unclear. Three of the included studies compared the sublineages of Omicron BA.1 versus BA.2. As compared with Delta, individuals infected with Omicron had 61% lower risk of death (RR 0.39, 95% CI 0.33 to 0.46) and 56% lower risk of hospitalisation (RR 0.44, 95% CI 0.34 to 0.56). Omicron was similarly associated with lower risk of intensive care unit (ICU) admission, oxygen therapy, and non-invasive and invasive ventilation. The pooled risk ratio for the outcome of hospitalisation when comparing sublineages BA.1 versus BA.2 was 0.55 (95% 0.23 to 1.30).

DISCUSSION

Omicron variant was associated with lower risk of hospitalisation, ICU admission, oxygen therapy, ventilation and death as compared with Delta. There was no difference in the risk of hospitalisation between Omicron sublineages BA.1 and BA.2.

PROSPERO REGISTRATION NUMBER

CRD42022310880.

The emergence of SARS-CoV-2 Omicron subvariants: current situation and future trends

The SARS-CoV-2 Omicron variant (B.1.1.529) has been the most recent variant of concern (VOC) established by the World Health Organization (WHO). Because of its greater infectivity and immune evasion, this variant quickly became the dominant type of circulating SARS-CoV-2 worldwide. Our literature review thoroughly explains the current state of Omicron emergence, particularly by comparing different omicron subvariants, including BA.2, BA.1, and BA.3. Such elaboration would be based on structural variations, mutations, clinical manifestation, transmissibility, pathogenicity, and vaccination effectiveness. The most notable difference between the three subvariants is the insufficiency of deletion (Δ69-70) in the spike protein, which results in a lower detection rate of the spike (S) gene target known as (S) gene target failure (SGTF). Furthermore, BA.2 had a stronger affinity to the human Angiotensin-converting Enzyme (hACE2) receptor than other Omicron sub-lineages. Regarding the number of mutations, BA.1.1 has the most (40), followed by BA.1, BA.3, and BA.3 with 39, 34, and 31 mutations, respectively. In addition, BA.2 and BA.3 have greater transmissibility than other sub-lineages (BA.1 and BA.1.1). These characteristics are primarily responsible for Omicron's vast geographical spread and high contagiousness rates, particularly BA.2 sub-lineages.

As the SARS-CoV-2 virus evolves, should Omicron subvariant BA.2 be subjected to quarantine, or should we learn to live with it?

It has been nearly 35 months since the COVID-19 outbreak. The pathogen SARS-CoV-2 has evolved into several variants. Among them, Omicron is the fifth variant of concern which have rapidly spread globally during the past 8 months. Omicron variant shows different characteristics from previous variants, which is highly infectious, highly transmissible, minimally pathogenic, vaccine and antibody tolerant; however, it is less likely to cause severe illness, resulting in fewer deaths. Omicron has evolved into five main lineages, including BA.1, BA.2, BA.3, BA.4, and BA.5. Before BA.5, Omicron BA.2 sublineage was the dominant strain all over the world for several months. The experience of prevention and treatment against BA.2 is worth studying and learning for overcoming other Omicron subvariants. Although the Omicron subvariant BA.2 is significantly less severe than that caused by ancestral strains, it is still far more dangerous than influenza, and its long-term sequelae are unknown. Effective treatments are currently limited; therefore, effective defense may be the key to controlling the epidemic today, rather than just "living with" the virus.

Viral load of SARS-CoV-2 Omicron is not high despite its high infectivity

Patients infected with the Omicron variant of severe acute respiratory syndrome coronavirus 2 has increased worldwide since the beginning of 2022 and the variant has spread more rapidly than the Delta variant, which spread in the summer of 2021. It is important to clarify the cause of the strong transmissibility of the Omicron variant to control its spread. In 694 patients with coronavirus disease 2019, the copy numbers of virus in nasopharyngeal swab-soaked samples and the viral genotypes were examined using quantitative polymerase chain reaction (PCR) and PCR-based melting curve analysis, respectively. Whole-genome sequencing was also performed to verify the viral genotyping data. There was no significant difference (p = 0.052) in the copy numbers between the Delta variant cases (median 1.5 × 10⁵ copies/μl, n = 174) and Omicron variant cases (median 1.2 × 10⁵ copies/μl, n = 328). During this study, Omicron BA.1 cases (median 1.1 ×10⁵ copies/μl, n = 275) began to be replaced by BA.2 cases (median 2.3 × 10⁵ copies/μl, n = 53), and there was no significant difference between the two groups (p = 0.33). Our results suggest that increased infectivity of the Omicron variant and its derivative BA.2 is not caused by higher viral loads but by other factors, such as increased affinity to cell receptors or immune escape.

Risk Factors Associated with Mortality in Hospitalized Patients with COVID-19 during the Omicron Wave in Brazil

Considering the imminence of new SARS-CoV-2 variants and COVID-19 vaccine availability, it is essential to understand the impact of the disease on the most vulnerable groups and those at risk of death from the disease. To this end, the odds ratio (OR) for mortality and hospitalization was calculated for different groups of patients by applying an adjusted logistic regression model based on the following variables of interest: gender, booster vaccination, age group, and comorbidity occurrence. A massive number of data were extracted and compiled from official Brazilian government resources, which include all reported cases of hospitalizations and deaths associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Brazil during the “wave” of the Omicron variant (BA.1 substrain). Males (1.242; 95% CI 1.196–1.290) aged 60–79 (3.348; 95% CI 3.050–3.674) and 80 years or older (5.453; 95% CI 4.966–5.989), and hospitalized patients with comorbidities (1.418; 95% CI 1.355–1.483), were more likely to die. There was a reduction in the risk of death (0.907; 95% CI 0.866–0.951) among patients who had received the third dose of the anti-SARS-CoV-2 vaccine (booster). Additionally, this big data investigation has found statistical evidence that vaccination can support mitigation plans concerning the current scenario of COVID-19 in Brazil since the Omicron variant and its substrains are now prevalent across the entire country.

Circulating Dynamics of SARS-CoV-2 Variants between April 2021 and February 2022 in Turkey

The diagnosis of new variants and monitoring their potential effects on diagnosis, therapeutics, and vaccines by genomic sequencing is essential to manage global public crises. In the current study, spike-genome next-generation sequencing was generated from 492 SARS-CoV-2 isolates to evaluate the mutations in Turkey from April 2021 to February 2022. The variant analysis was performed using (Coronavirus Antiviral and Resistance Database (CoV-RDB) by Stanford University). We revealed that the lineages Alpha (B.1.1.7), Beta (B.1.351), Delta (B.1.617.2), Eta (B.1.525), variant of interest (VOI), lota (B.1.526), Zeta (P.2), Omicron (B.1.1.529), and Omicron BA.1 (B.1.1.529.1) were in the circulation in Turkey during the given period. The most common lineages were B.1.1.7, B.1.617.2, B.1.1.529, and B.1.1.529.1 SARS-CoV-2 variant circulation in Turkey seems highly heterogenetic; however, quite similar to the global epidemiologic analysis. The existence of globally circulating variants in the same chronological order in Turkey can be a guide for precautions, treatment, and vaccine options to be taken in the future.

SARS-CoV-2 and COVID-19: A Narrative Review

The World Health Organisation has reported that the viral disease known as COVID-19, caused by SARS-CoV-2, is the leading cause of death by a single infectious agent. This narrative review examines certain components of the pandemic: its origins, early clinical data, global and UK-focussed epidemiology, vaccination, variants, and long COVID.

Current vaccine strategies against SARS-CoV-2: Promises and challenges

In the years since the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic began and spread across the globe, lessons have been learned about the challenges and opportunities that a pandemic brings to humankind. Researchers have produced many vaccines at unprecedented speed to protect people, but they have also been cognizant of the challenges presented by a new and unexpected infectious disease. The scope of this review is to examine the path of vaccine discovery so far and identify potential targets. Here, we provide insight into the leading vaccines and their advantages and challenges. We discuss the emerging mutations within the SARS-CoV-2 spike protein and other issues that need to be addressed to overcome coronavirus disease 2019 (COVID-19) completely. Future research is needed to develop a cheap, temperature-stable vaccine providing long-term immunity that protects the upper respiratory tract.

Omicron BA.2 Lineage, the "Stealth" Variant: Is It Truly a Silent Epidemic? A Literature Review

The epidemic curve of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is silently rising again. Worldwide, the dominant SARS-CoV-2 variant of concern (VOC) is Omicron, and its virological characteristics, such as transmissibility, pathogenicity, and resistance to both vaccine- and infection-induced immunity as well as antiviral drugs, are an urgent public health concern. The Omicron variant has five major sub-lineages; as of February 2022, the BA.2 lineage has been detected in several European and Asian countries, becoming the predominant variant and the real antagonist of the ongoing surge. Hence, although global attention is currently focused on dramatic, historically significant events and the multi-country monkeypox outbreak, this new epidemic is unlikely to fade away in silence. Many aspects of this lineage are still unclear and controversial, but its apparent replication advantage and higher transmissibility, as well as its ability to escape neutralizing antibodies induced by vaccination and previous infection, are rising global concerns. Herein, we review the latest publications and the most recent available literature on the BA.2 lineage of the Omicron variant.

Case Report: The Experience of Managing a Moderate ARDS Caused by SARS-CoV-2 Omicron BA.2 Variant in Chongqing, China: Can We Do Better?

Background

The severe coronavirus disease 2019 (COVID-19) pandemic is still raging worldwide, and the Omicron BA.2 variant has become the new circulating epidemic strain. However, our understanding of the Omicron BA.2 variant is still scarce. This report aims to present a case of a moderate acute respiratory distress syndrome (ARDS) caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) Omicron BA.2 variant and to discuss some management strategies that may benefit this type of case.

Case Presentation

A 78-year-old man, who had four negative nucleic acid tests and a fifth positive, was admitted to our hospital. This patient was generally good upon admission and tested negative for anti-SARS-CoV-2 antibodies even after receiving two doses of the COVID-19 vaccine. On the 7th day of hospitalization, he developed a moderate ARDS. Improved inflammatory index and decreased oxygen index were primarily found in this patient, and a series of treatments, including anti-inflammation and oxygen therapies, were used. Then this patient’s condition improved soon and reached two negative results of nucleic acid tests on the 18th day of hospitalization.

Conclusion

At-home COVID-19 rapid antigen test could be complementary to existing detection methods, and the third booster dose of COVID-19 vaccine may be advocated in the face of the omicron BA.2 variant. Anti-inflammatory and oxygen therapies are still essential treatments for ARDS patients infected with SARS-CoV-2 Omicron BA.2 variant.