OMICRON: Virology, immunopathogenesis, and laboratory diagnosis

Bazargan, Mahsa; Elahi, Reza; Esmaeilzadeh, Abdolreza

doi:10.1002/jgm.3435

Cited by 38 publications

(52 citation statements)

References 207 publications

(329 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Older adults often have more comorbidities; poor nutrition; and poor heart, lung, and kidney function, resulting in their low natural immunity and susceptibility to viruses ( 9 ). Although previous studies have suggested that Omicron has an immune evasion effect on vaccines or antibodies from previous infections ( 11 – 13 ), the infection and severe illness rates increase drastically when the patient is not vaccinated ( 8 , 10 ). In this study, there was no statistically significant difference in vaccination status (35 unvaccinated persons) ( P = 0.058), which may be related to the smaller sample size.…”

Section: Discussionmentioning

confidence: 97%

“…This may be related to the small sample size, and it is unclear whether it is related to re-positivity based on the current study. Depression may lead to decreased immunity, and immune escape by Omicron is common ( 13 ). Thus, patients may be more prone to re-positivity, which also explains why once the patient is infected with Omicron, it is difficult to fight Omicron through their own immune function.…”

Section: Discussionmentioning

confidence: 99%

“…The high infectivity made the Omicron threaten more people, especially for elderly ( 8 , 9 ), and one study have demonstrated that rate of severe illness would not be decreased for some population without vaccination ( 10 ). Experimental studies show that Omicron has many mutations in its structure compared with SARS-CoV-2, which increases the risk of reinfection ( 2 , 11 – 13 ). In previous outbreaks, the total reinfection rate of the SARS-CoV-2 variant was <2% ( 6 ).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Older age and depressive state are risk factors for re-positivity with SARS-CoV-2 Omicron variant

Peng

Duan

et al. 2022

Front. Public Health

View full text Add to dashboard Cite

BackgroundThe reinfection rate of SARS-CoV-2 Omicron variant is high; thus, exploring the risk factors for reinfection is important for the effective control of the epidemic. This study aimed to explore the effects of psychological and sleep factors on re-positivity with Omicron.MethodsThrough a prospective cohort study, 933 adult patients diagnosed with Omicron BA.2.2 infection and testing negative after treatment were included for screening and follow-up. We collected data on patients' demographic characteristics, SARS-CoV-2 Omicron vaccination status, anxiety, depression, and sleep status. Patients underwent nucleic acid testing for SARS-CoV-2 Omicron for 30 days. Regression and Kaplan-Meier analyses were used to determine the risk factors for re-positivity of Omicron.ResultsUltimately, 683 patients were included in the analysis. Logistic regression analysis showed that older age (P = 0.006) and depressive status (P = 0.006) were two independent risk factors for Omicron re-positivity. The odds ratios of re-positivity in patients aged ≥60 years and with a Patient Health Questionnaire-9 (PHQ-9) score ≥5 was 1.82 (95% confidence interval:1.18–2.78) and 2.22 (1.27–3.85), respectively. In addition, the time from infection to recovery was significantly longer in patients aged ≥60 years (17.2 ± 4.5 vs. 16.0 ± 4.4, P = 0.003) and in patients with PHQ-9≥5 (17.5 ± 4.2vs. 16.2 ± 4.5, P = 0.026). Kaplan–Meier analysis showed that there was a significantly higher primary re-positivity rate in patients aged ≥60 years (P = 0.004) and PHQ-9 ≥ 5 (P = 0.007).ConclusionThis study demonstrated that age of ≥60 years and depressive status were two independent risk factors for re-positivity with Omicron and that these factors could prolong the time from infection to recovery. Thus, it is necessary to pay particular attention to older adults and patients in a depressive state.

show abstract

Section: Discussionmentioning

confidence: 97%

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Older age and depressive state are risk factors for re-positivity with SARS-CoV-2 Omicron variant

Peng

Duan

et al. 2022

Front. Public Health

View full text Add to dashboard Cite

show abstract

“…Nevertheless, the arrival of the Omicron variant marked a turning point regarding the frequency of reinfections detected, not seen before for other VOCs, with a 10-fold increase in the proportion of cases ( Bastard et al., 2022 ; Nunes et al., 2022 ; Pulliam et al., 2022 ). This characteristic of Omicron is attributed to the more than 30 mutations identified in this variant, mainly in the RBD of the Spike protein and together with insertions and deletions ( Akkız, 2022 ), that confer an increased ability to evade immune protection, including that acquired by vaccination ( Bazargan et al., 2022 ). As expected, the incidence of suspected reinfections detected in Ecuador in this study increased to 2.45% during the Omicron period, and sequencing confirmed that the reinfecting variants were from this clade ( Figure 3 ).…”

Section: Discussionmentioning

confidence: 99%

Occurrence of SARS-CoV-2 reinfections at regular intervals in Ecuador

Guevara

Prado-Vivar

Márquez

et al. 2022

Front. Cell. Infect. Microbiol.

View full text Add to dashboard Cite

SARS-CoV-2 reinfection is defined as a new infection with a different virus variant in an individual who has already recovered from a previous episode of COVID-19. The first case of reinfection in the world was described in August 2020, since then, reinfections have increased over time and their incidence has fluctuated with specific SARS-CoV-2 variant waves. Initially, reinfections were estimated to represent less than 1% of total COVID-19 infections. With the advent of the Omicron variant, reinfections became more frequent, representing up to 10% of cases (based on data from developed countries). The frequency of reinfections in Latin America has been scarcely reported. The current study shows that in Ecuador, the frequency of reinfections has increased 10-fold following the introduction of Omicron, after 22 months of surveillance in a single center of COVID-19 diagnostics. Suspected reinfections were identified retrospectively from a database of RT-qPCR-positive patients. Cases were confirmed by sequencing viral genomes from the first and second infections using the ONT MinION platform. Monthly surveillance showed that the main incidence peaks of reinfections were reached within four to five months, coinciding with the increase of COVID-19 cases in the country, suggesting that the emergence of reinfections is related to higher exposure to the virus during outbreaks. This study performed the longest monitoring of SARS-CoV-2 reinfections, showing an occurrence at regular intervals of 4-5 months and confirming a greater propensity of Omicron to cause reinfections.

show abstract

“…More specifically, OPNI exhibited an independent association with disease severity and mortality, even in the period of omicron variant predominance. It has been well established that the omicron variant contains a markedly higher number of novel mutations than other variants in its spike protein, the majority of which are in its receptor binding region, which increases transmissibility, while decreasing antibody and vaccination responses (38).…”

Section: Discussionmentioning

confidence: 99%

Onodera's prognostic nutritional index: Comparison of its role in the severity and outcomes of patients with COVID‑19 during the periods of alpha, delta and omicron variant predominance

et al. 2022

View full text Add to dashboard Cite

Coronavirus disease 2019 (COVID-19) has posed a severe public health threat worldwide, affecting the function of multiple organs in affected individuals, in addition to respiratory function. Several strains of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been circulating worldwide since it first arose, with some of these having the ability to escape from natural or vaccine-mediated immunity. The Onodera's prognostic nutritional index (OPNI), which is derived from the peripheral lymphocyte count and serum albumin, has been reported to be significantly associated with a poor survival rate and post-operative complications in patients with various diseases and in some studies on patients with COVID-19. The aim of the present retrospective study was to evaluate and compare the efficacy of OPNI as a prognostic indicator in patients with COVID-19 during the periods of alpha, delta and omicron variant predominance.Adult patients who visited or were hospitalized due to SARS-CoV-2 infection were included, covering the second, third (alpha variant), fourth (delta variant) and fifth (omicron variant) pandemic waves. According to the results obtained, OPNI exhibited a statistically significant difference among patients with mild/moderate, severe and critical disease, with the lowest values observed in patients with critical disease in all the pandemic waves examined. Moreover, OPNI was found to be an independent prognostic biomarker of intubation and mortality in patients with COVID-19, according to multivariate logistic regression analysis, including as confounders an age >65 years, the male sex and the presence of comorbidities in all periods examined.

show abstract

OMICRON: Virology, immunopathogenesis, and laboratory diagnosis

Cited by 38 publications

References 207 publications

Older age and depressive state are risk factors for re-positivity with SARS-CoV-2 Omicron variant

Older age and depressive state are risk factors for re-positivity with SARS-CoV-2 Omicron variant

Occurrence of SARS-CoV-2 reinfections at regular intervals in Ecuador

Onodera's prognostic nutritional index: Comparison of its role in the severity and outcomes of patients with COVID‑19 during the periods of alpha, delta and omicron variant predominance

Contact Info

Product

Resources

About