2) This study investigated a controlled human infection model (CHIM) using SARS-CoV-2 in individuals with pre-existing immunity from prior infection and/or vaccination.
36 volunteers with documented prior SARS-CoV-2 infection were enrolled and given intranasal inoculations ...3
3) ...of increasing doses of SARS-CoV-2, from 1x101 to 1x105 TCID50.
Despite dose escalation, sustained infection was not induced in any volunteers. 5 volunteers (14%) showed transient infection based on PCR-detected virus outside the immediate post-inoculation period.
4) Transiently infected volunteers had significantly lower baseline mucosal and systemic antibody levels against SARS-CoV-2, compared to uninfected volunteers.
Transiently infected volunteers also had significantly lower baseline IFNฮณ responses ...
5) ...to a CD8+ T cell epitope peptide pool by ELISpot.
39% of volunteers subsequently developed asymptomatic community-acquired omicron infection during follow-up.
The study demonstrated potent protective immunity against homologous re-infection induced ...
6) ...by prior infection, vaccination, or their combination. It was not able to establish a CHIM that reliably induces infection in those with pre-existing immunity.
In summary, this first SARS-CoV-2 CHIM in individuals ...
7) ... with prior immunity showed protection against sustained re-infection but identified some correlates of the weaker transient infection seen in a small number of volunteers. It provided validation of the safety and relevance of SARS-CoV-2 CHIMs.
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2) Cuba conducted a nationwide pediatric vaccination campaign in September 2021 using the heterologous SOBERANA-02-Plus vaccine scheme (2 doses of SOBERANA-02 followed by 1 dose of SOBERANA-Plus). Over 95% of children aged 2-18 were fully vaccinated by December 2021.
3) The study evaluated the real-world effectiveness of this vaccine scheme against symptomatic COVID-19 infection and severe disease in children aged 2-11 during Cuba's Omicron wave from December 2021 to June 2022.
2) ... that plays a crucial role in the immune system. They are located on the surface of immune cells and are responsible for recognizing specific molecules from pathogens, as bacteria, viruses, and fungi. When TLRs detect these molecules ...
3) ...they trigger an immune response to eliminate the invading pathogens. TLRs are essential for the body's defense against infections and are involved in inflammation and the activation of other immune cells.
2) The study aims to examine the protein-protein interaction (PPI) network between SARS-CoV-2 viral proteins and human host proteins. This can provide insights into potential therapeutic targets and drug repurposing opportunities for COVID-19
3) A PPI network was constructed consisting of 29 SARS-CoV-2 viral proteins interacting with 2896 host proteins. 176 host genes were identified that interact with all viral proteins, indicating their importance.
2) The study analyzed 17 pediatric patients in Korea who experienced severe neurological manifestations associated with SARS-CoV-2 infection during the Omicron variant-predominant period from January to April 2022.
3) Over half (11/17) of the patients had pre-existing neurological disabilities and 9 met the criteria for MIS-C (multisystem inflammatory syndrome in children). Only 1 patient was vaccinated.
Severe neurological manifestations included acute necrotiwezing encephalopathy ...
2) The study assessed the kinetics of antibodies against SARS-CoV-2 among 137 employees of the Pasteur Institute of Tunis who had confirmed COVID-19 infection between September 2020-March 2021.
3) Antibody levels were measured at 1, 3, 6, 9 and 12 months post-infection. Neutralizing antibodies and anti-S-RBD antibodies significantly decreased between months 1-3 but increased from months 3-6.
2) This study aims to investigate the impact of the Omicron variant on young people 12 months after infection. The study included 345 young people who had their first laboratory-confirmed infection with the Omicron variant and 360 young people who were reinfected ...
3) ...with the Omicron variant.
They completed an online questionnaire assessing demographics, symptoms, and their impact at different time points. The most common symptoms reported at 12 months post-testing were tiredness and sleeping difficulties.