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COVID-19
Published in Stephen T. Sinatra, Mark C. Houston, Nutritional and Integrative Strategies in Cardiovascular Medicine, 2022
Since most COVID-19 infections are asymptomatic or have minimal symptoms, serology has evolved into an important tool to determine the true prevalence of COVID-19 infections in the population from a public health perspective. Additionally, there is a push to do antibody testing post-vaccination or confirmed COVID-19 infection to determine immune status. Antibodies can appear as early as a few days in COVID-19 patients.28 Serology tests have an analytical sensitivity of 100% and a specificity of 99.6%. Unlike most infections where IgM precedes IgG, in COVID-19, they can appear simultaneously and then IgM wanes over time. The half-life of antibodies is approximately 73 days.29,30 Even if antibodies fall below detectable levels after an immune response, memory B-cells can respond to new exposure within minutes.
Ayurveda and COVID-19
Published in Srijan Goswami, Chiranjeeb Dey, COVID-19 and SARS-CoV-2, 2022
A positive take home from the pandemic is the fact that literally hundreds of thousands of people who tested Covid-19 positive have recovered. A few did so with medical intervention but in most cases, their immune system bailed them out of the crisis. Nature has equipped the human being to protect itself from millions of known and unknown microbes. The immune system in every life form is designed to combat intruders like bacteria, viruses, and any toxic material like bee stings or scorpion venom that enters the body. The immune system identifies the pathogen and creates an antibody to combat it. After a raging battle, which may be seen in the form of swelling, fever, redness, and pain, the immune system overpowers the pathogen and cures the person. Most of us have experienced a number of infections like common colds, stomach infections, conjunctivitis, or sinusitis. Some of us have recovered from serious infections like pneumonia or bronchitis. A strong immune system is equipped to combat most pathogens. If a foreign material like a thorn or wood splinter enters the body, the immune system isolates it from the rest of the body and eventually expels it from the system. At times, when it fails to expel the foreign body, it sequesters the thorn or splinter and builds a tough layer around it, which, for all practical purposes, separates it from the body. Some of us have experienced this phenomenon in the form of a corn.
The immune and lymphatic systems, infection and sepsis
Published in Peate Ian, Dutton Helen, Acute Nursing Care, 2020
Michelle Treacy, Caroline Smales, Helen Dutton
When an antigen or ‘foreign’ substance is detected, B cells or plasma cells (found in lymphoid tissue) are stimulated to secrete large quantities of antibodies, which bind to specific antigens, forming the antigen–antibody complex. Each antibody has a specific adapter site, epitope, or ‘lock’, that fits a particular antigen, or ‘key’. Each antibody recognises the shape of the antigen to which they are programmed to bind.
Genomic and serological assessment of asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections in child labor
Published in Pathogens and Global Health, 2022
Niloofar Najafi, Hoorieh Soleimanjahi, Shadab Shahali, Mahmoud Reza Pourkarim, Marijn Thijssen, Fatemeh Fotouhi, Taravat Bamdad, Kayhan Azadmanesh, Zeynab Nasiri, Neda Afzali, Mohammad Reza Jabbari, Atefeh Yari, Hesam Karimi, Mohammad Hadi Karbalaei Niya
In December 2019, a cluster of pneumonia cases with unknown etiology were reported in Wuhan, China. In early January 2020, a novel coronavirus, named severe acute respiratory distress syndrome coronavirus 2 (SARS-CoV-2), was identified as the causative agent [1]. From Wuhan, the virus quickly spread across the globe and urged the World Health Organization (WHO) to announce a pandemic on 11 March 2020 [2]. SARS-CoV-2 is a member of the Coronaviridae family and was initially isolated from the patient’s respiratory tract. An infection with this virus can cause a wide-spectrum of respiratory and systemic symptoms, collectively referred to as coronavirus disease 2019 (COVID-19) [3]. Similar to previous coronaviruses SARS and MERS, the newly emerged virus is classified as a member of the Orthocoronavirinae sub-family of betacoronavirus genus [4]. Diagnosis of SARS-CoV-2 infection is based on either serological immune assays (IA) or molecular assays, such as real-time reverse transcription polymerase chain reaction (RT-PCR). Currently, RT-PCR is the gold standard for diagnosing SARS-CoV-2 infection [5]. Antibody testing for SARS-CoV-2 enables the identification of past exposure to the virus, even after the virus has been cleared by the immune system. Combining both serological methods and RT-PCR allows the identification of resolved and current infection, respectively, which are therefore valuable techniques in epidemiological studies [5–8].
A Differential Immune Modulating Role of Vitamin D in Urinary Tract Infection.
Published in Immunological Investigations, 2022
Obviously, a protective antibody response can be induced against infection and/or following vaccination (Bartlett et al. 2009; Hopkins and Uehling 1995). Our findings indicated higher levels of IgG and IgA in the sera of patients than those in the control group without any significant difference in the serum levels of IgM. The bacterial adherence and colonization could have resulted in the recall of serum antibody response since this might correspond with inhibition of bacterial adhesion which was in agreement with previous studies (Alteri et al. 2009; Imani Fooladi et al. 2014; Layton and Smithyman 1983). Presumably, proper vitamin D levels might be important to prepare the microenvironment for B cell activation to mount IgG production as a possible result of selective changes in the nature and the extent of VDR binding sites mediated by antigen stimulation, although the production level of IgA might be enhanced by the presence of bacteria resulted in a proper/sufficient antigen experience. Alteration of cytokine production may postulate to be involved in this effect. In recent studies, it has been established that the IL-10 synthesis primarily by mast cells involves in a failure to attenuate persistent bacterial burden in the bladder due to the impairment of class switching and defective production of antigen-specific antibodies (Choi et al. 2016; Hopkins et al. 1998; Pellegrino et al. 2003).
Two-tiered SARS-CoV-2 seroconversion screening in the Netherlands and stability of nucleocapsid, spike protein domain 1 and neutralizing antibodies
Published in Infectious Diseases, 2021
Anja Garritsen, Anja Scholzen, Daan W. A. van den Nieuwenhof, Anke P. F. Smits, E. Suzan Datema, Luc S. van Galen, Milou L. C. E Kouwijzer
Since early on in the COVID-19 pandemic, it has been suggested that serological tests could be used to issue so-called ‘immunity passports’ [18–20], a discussion re-emerging now that the first vaccines have become available. This has caused heated discussions about potential ethical, equitable and legal implications as well as public health ramifications due to potentially increased/encouraged risky behaviour by ‘immunity passport’ holders [17,21]. One often used argument in this context is that it is not yet established whether antibodies confer protective immunity to further symptomatic infection or transmission, which amount of antibody is needed for protection or how long any such immunity lasts. In the mean-time, a wealth of data has emerged that strongly supports both the stability (as far as it can be evaluated up to now) and protective efficacy of SARS-CoV-2 neutralizing antibodies.