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Crossroads of Pathogens: The Evolving Threat of Avian Influenza

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Influenza viruses are infamous for their ability to mutate and adapt, making the study of their evolution critical for public health. Some like H5N1 are severe, others as H7N3 are typically present with mild symptoms. The classification of influenza subtypes relies on the hemagglutinin (H) and neuraminidase (N) proteins on the viral surface, with 18 H subtypes and 11 N subtypes combining into diverse influenza strains. While most pose limited risks to humans, certain mutations can significantly alter their behavior. Case 1: Mutated H5N1 in a Vancouver Teen Canadian teen, who lives in the Fraser Health Region of British Columbia, first developed symptoms on Nov. 2 and was tested on Nov. 8, with a positive result confirmed on Nov. 9.  It was the first positive case of bird flu detected in a human in Canada. The teenager, hospitalized with a mutated H5N1 strain, was unconscious for over two weeks. The teen has made progress and is expected to recover. Alarmingly, this strain exhibits ...

First Documented Transmission of a Newly Minted Hybrid SARS-CoV-2 Variant

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In a recent case report, Swedish scientists documented the first known transmission of a novel recombinant SARS-CoV-2 variant. The case highlights how a patient co-infected with two different strains—sublineages of XBB (HV.1) and BA.2.86.1—generated and transmitted a hybrid variant to another patient within a hospital setting. In October 2023, routine genomic surveillance in Stockholm identified a recombinant variant in a patient (Patient B). This hybrid virus combined genetic material from two distinct lineages: the 5′ part of the genome from HV.1 and the 3′ part from BA.2.86.1. The recombination occurred at the orf1b and S gene junction, producing a novel variant not observed in other Swedish patients. Meanwhile, another patient (Patient A), co-hospitalized in the same ward, was found to be co-infected with both HV.1 and BA.2.86.1. Sequencing revealed that about 30% of the virus in Patient A came from the BA.2.86.1 lineage. The two patients shared six rare mutations, confirming that ...

Cytokine Storms After COVID-19 Vaccination

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Severe post-vaccinal complications could be driven by an overactive immune response. In a new case series , recently published in Cureus, three rheumatic disease patients with low disease activity needed hospitalization and new biological treatments, and one patient died after her 4th dose of SARS-CoV-2 mRNA vaccine. Cytokine analysis showed elevated levels of IL-1β, IL-6, IL-17, and TNF-α, indicating a cytokine storm, possibly triggered by IL-6 amplification (IL-6 Amp). This mechanism involves excessive IL-6 production through a feedback loop activated by simultaneous stimulation of NF-κB and STAT3 pathways Case 1: Acute Exacerbation of Interstitial Pneumonia in an 80-Year-Old Woman An 80-year-old woman with a history of rheumatoid arthritis (RA) had been in remission for five years thanks to a regimen including subcutaneous tocilizumab (TCZ-SC) and tacrolimus. However, after receiving the Pfizer-BioNTech vaccine, she developed severe dyspnea requiring oxygen. Her CT scan revealed new...

COVID in May

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Concerns about a potential resurgence of COVID-19 are mounting as summer 2024 approaches.  This is driven by several indicators, including social media posts, healthcare data, and wastewater surveillance across different regions. Our study findings corroborate this trend.  While many forecasters anticipate a surge, others expect a gradual increase through the end of May, and then a decline again around early June. Reports from social media suggest emerging clusters of COVID-19 in Texas, several Canadian provinces, the UK, and on cruises in northern regions such as a Norwegian cruise to Alaska.  Data from Alberta's Respiratory virus dashboard   (total weekly laboratory-confirmed COVID-19 cases) and wastewater surveillance in Calgary indicate an uptick in COVID-19 cases starting April 2024. The most recent statistics from Alberta Health reveal a significant increase in hospitalizations due to COVID-19, with 114 individuals currently hospitalized—an incr...

The offshoots of JN.1 in the Evolutionary Trajectory of COVID-19

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While the current SARS-COV-2 viral activity levels may seem reassuring ( back to the levels seen in October-November 2023 ), the evolving world of JN.1 offshoots, where the next generation of variants is taking shape, presents a compelling case for anticipating the potential challenges that lie ahead.  From the widespread presence of JN.1.16 across continents to the emerging dominance of JN.1.13 in the U.S., the current variant landscape is rapidly shifting, although the potential implications for the future are not quite clear.  The roots of the pandemic can be traced back to lineage A, with many initial sequences originating from China and subsequently spreading globally, including to regions such as South East Asia, Japan, South Korea, Australia, the USA, and Europe. Lineage B followed as the second major haplotype, with subsequent evolutions leading to the emergence of various sublineages. In 2020, we witnessed the emergence of variants such as Alpha (B.1.1.7) and Delta (...

The Persistence of COVID-19 Reinfections

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COVID-19 has posed numerous challenges since its emergence, and one area of concern has been the phenomenon of frequent reinfections.  In a recent study, based on UK's national COVID-19 Infection Survey, seven participants experienced COVID-19 reinfection five times.  Among these participants, identified as white females aged 21–50 years, three reported having a long-term health condition, and two were healthcare workers. The study also analyzed the variants, symptoms, and cycle threshold (Ct) values associated with these reinfections (see table) The study revealed that while reinfections increased after the emergence of Omicron variants, they were generally less severe than initial infections, associated with lower viral load and fewer reported symptoms compared to first infections. Several factors were identified as influencing the risk of reinfection. Age played a significant role, with individuals aged 30–45 years being at higher risk ( likely due to increased exposure )....

Chronic SARS-CoV-2 Shedding

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Chronic viral shedding, a condition where the virus continues to be released from an individual's body long after the initial infection, has been observed in many infectious diseases, including COVID-19.  In such cases, individuals may remain asymptomatic or experience only mild symptoms while the virus persists. It remains detectable in repeated tests over an extended period and can still infect others even in nasal swab is negative (which happens quite often ). This was evident in our study.    Recent research by Conway et al. (2024) highlights the possibility of chronic SARS-CoV-2 infection, extending over several months and potentially years. Other studies have documented prolonged asymptomatic infections and extended viral shedding in moderate to severe beyond hospital discharge. Analysis of sequencing data on UK samples taken between 2 November 2020 and 15 August 2022 lead to estimates that 0.1–0.5% of infections may become persistent with typically rebounding high ...