ABSTRACT
Non-SARS coronaviruses (HCoVs) contribute substantially to seasonal common colds. Their structural homology with SARS-CoV-2 suggests a possible cross-reactivity and cross-protection. The presence of IgG to the most common HCoVs (NL63, 229E, OC43, HKU1) in correlation with RBD-specific IgG and IgA, and the susceptibility to SARS-CoV-2 infection was evaluated in 48 individuals with recently diagnosed moderate SARS-CoV-2 infection (A, n=24) or intensive exposure to SARS-CoV-2 (B, n=24). Anti-S1 IgG for each of the four HCoVs, alongside with RBD-IgG and RBD-IgA were evaluated using ELISA (Creative Diagnostics, USA;Euroimmune, Germany). RBD-specific IgG and IgA were detected in 37% and 71% of group A (average levels 8.5 and 6.8) and 42% and 29% of group B (average levels 3.4 and 4.6 respectively, p < 0.05). IgG specific for NL63, 229E, and OC43 was present in 100.0%, and for HKU-1 - in 94% of tested samples (average index 7.4, 3.9, 4.1, and 2.6, respectively). The levels of IgG to NL63 and 229E did not differ significantly between the groups (7.6 vs.7.2;3.7 vs. 4.1, p > 0.05), nor did correlate with anti-SARS-CoV-2 response. HKU-1-specific IgG was significantly decreased in COVID-19 patients (A) as compared to SARS-CoV-2 resistant donors (B): 1.98vs.3.2, p < 0.01. Curiously, OC43-specific IgG was lower in the group with intensive exposure to SARS-CoV-2 (3.5vs.4.7, p < 0.01), and correlated with RBD-specific IgA (R=0.42, p < 0.05). IgG to seasonal coronaviruses is commonly detected, but only HKU-1-specific IgG was associated with resistance to SARS-CoV-2 infection. OC43-specific IgG may be induced simultaneously with RBD-specific IgA and interfere with SARS-CoV-2 neutralization.
ABSTRACT
Coronaviruses are a large family of viruses that cause diseases ranging from mild flu-like symptoms to more severe illnesses. The purpose of this study was to present a survey on anosmia in COVID-19 among Bulgarian soldiers from Varna. For the period from July 01, 2020, to December 16, 2020, a survey was conducted among 80 cadets studying in a regular form of training at the Nikola Vaptsarov Naval Academy – Varna. The main clinical signs and symptoms among the participants were: anosmia (68.7% of cadets), headache (38.7%), fatigue (35.0%), fever (30.0%), cough (28.7%), dyspnea (13.7%), diarrhea (8.7%), nausea/ vomiting (8.7%), asymptomatic cases (21.2%). We found that 35% (28/80) of the participants were without anosmia, 17.5% (14/80) – with a partial anosmia, and 47.5% (38/80) – a complete anosmia. Regarding vaccination against COVID-19, the following was found: 26.2% of the cadets declared that they were willing to be vaccinated, and 73.8% – did not want to be vaccinated. In conclusion, soldiers are exposed to an increased risk of transmitting infectious diseases due to coexistence and intensive contacts. The SARS-CoV-2 proliferation control strategy has a key role to play in controlling the pandemic and its consequences. © 2021, Central Medical Library Medical University – Sofia. All rights reserved.
ABSTRACT
Coronavirus infections are common in both animals and humans. This article presented an overview of the scientific literature on SARS-CoV-2 infection. Various aspects of this infection have been considered: a common characteristic and part of the international experience. Improving knowledge on COVID-19 is an important step in dealing with this infection.