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NGS technologies for detection of SARS-CoV-2 strains and mutations
Published in Sanjeeva Srivastava, Multi-Pronged Omics Technologies to Understand COVID-19, 2022
Manisha Choudhury, Ayushi Verma, Ankit Halder, Arup Acharjee
The WGS data reveals insights about the genomic variants like single-nucleotide polymorphisms (SNPs), insertions, and deletions that drive the organism toward new strains to counter the host’s immune system. For instance, the phenomenon of “Antigenic Drift” and “Antigenic Shift” is quite common in influenza viruses (H. Kim, Webster, and Webby 2018). It is noteworthy that a new lineage, “B.1.1.7”, could be detected, and several significant mutations could be identified. The rapid extension of the lineages signifies the importance of genomic and epidemiological surveillance (“Preliminary Genomic Characterisation of an Emergent SARSCoV-2 Lineage in the UK Defined by a Novel Set of Spike Mutations—SARS-CoV-2 Coronavirus/NCoV-2019 Genomic Epidemiology” 2020).
Human physiology, hazards and health risks
Published in Stephen Battersby, Clay's Handbook of Environmental Health, 2023
Revati Phalkey, Naima Bradley, Alec Dobney, Virginia Murray, John O’Hagan, Mutahir Ahmad, Darren Addison, Tracy Gooding, Timothy W Gant, Emma L Marczylo, Caryn L Cox
The viral genome can undergo genetic changes when transferred from one host to another, an adaptive response to any resistance acquired by the hosts over time. This process of adaptation occurs in a number of ways, for example, antigenic drift, which entails small changes to the viral genome over time that can confer resistance to a range of antiviral drugs. Antigenic shift entails a sudden, major change in the viral genome, resulting in a new strain which hosts have little or no acquired immunity to, for example, changes to the influenza virus leading to epidemics or pandemics. Viruses can be diagnosed using a variety of methods that include the following:
Human physiology, hazards and health risks
Published in Stephen Battersby, Clay's Handbook of Environmental Health, 2016
David J. Baker, Naima Bradley, Alec Dobney, Virginia Murray, Jill R. Meara, John O’Hagan, Neil P. McColl, Caryn L. Cox
The viral genome can undergo genetic changes when transferred from one host to another, an adaptive response to any resistance acquired by the hosts over time. This process of adaptation occurs in a number of ways, for example antigenic drift, which entails small changes to the viral genome over time that can confer resistance to a range of antiviral drugs. Antigenic shift entails a sudden, major change in the viral genome, resulting in a new strain, which hosts have little or no acquired immunity to, for example changes to the influenza virus leading to epidemics or pandemics. Viruses can be diagnosed using a variety of methods that include the following:Serology (usually blood) – this is the mainstay of laboratory diagnosis of viral infections. Viral serologic testing monitors the immune system’s antibody response to viral antigen exposure, including both infection and immunisation. Serological diagnosis involves the use of a variety of techniques that are constantly evolving to improve both the accuracy of the test result and also the speed at which the results can be known.Direct examination of a specimen can be undertaken to detect viral antigens, for example, the use of immunoflourescence techniques to detect influenza viruses. Other methods of direct examination include electron microscopy to visualise viral particles in a specimen such as fluid from vesicles and tissue.Molecular methods such as polymerase chain reaction (PCR) and nucleic acid based amplification techniques are increasingly utilised by laboratories. These methods involve the amplification of viral genetic material such as RNA and DNA to enable the qualitative and quantitative detection of the viral genome.
Principles of risk decision-making
Published in Journal of Toxicology and Environmental Health, Part B, 2022
Daniel Krewski, Patrick Saunders-Hastings, Patricia Larkin, Margit Westphal, Michael G. Tyshenko, William Leiss, Maurice Dusseault, Michael Jerrett, Doug Coyle
A global infectious disease outbreak, such as the recent COVID-19 pandemic caused by the SARS-CoV-2 virus, may exert enormous public health impact: as of this writing, the World Health Organization (2022) estimates there have been over 545 million cases of COVID-19, and over 6 million deaths worldwide. Such outbreaks emerged as a result of an antigenic shift, wherein genetic components of viruses re-assort to produce a novel viral strain to which humans possess no appreciable immunity (Zambon 1999). If the disease can be transmitted easily between humans and manifest in diseases, a global pandemic may thus occur. Over the past one hundred years, the combined global burden of the 1918 Spanish flu, 1957 Asian flu, 1968 Hong Kong flu, and 2009 swine flu has amounted to tens of millions of infections, hospitalizations, and deaths, as well as billions of dollars in associated health and socioeconomic costs (Saunders-Hastings and Krewski 2016).