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Vaccines ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 46
Author(s):  
Marc Scherlinger ◽  
Luc Pijnenburg ◽  
Emmanuel Chatelus ◽  
Laurent Arnaud ◽  
Jacques-Eric Gottenberg ◽  
...  

Introduction: Few data are available concerning the effect of SARS-CoV-2 vaccination on the persistent symptoms associated with COVID-19, also called long-COVID or post-acute sequelae of COVID-19 (PASC). Patients and methods: We conducted a nationwide online study among adult patients with PASC as defined by symptoms persisting over 4 weeks following a confirmed or probable COVID-19, without any identified alternative diagnosis. Information concerning PASC symptoms, vaccine type and scheme and its effect on PASC symptoms were studied. Results: 620 questionnaires were completed and 567 satisfied the inclusion criteria and were analyzed. The respondents’ median age was 44 (IQR 25–75: 37–50) and 83.4% were women. The initial infection was proven in 365 patients (64%) and 5.1% had been hospitalized to receive oxygen. A total of 396 patients had received at least one injection of SARS-CoV-2 vaccine at the time of the survey, after a median of 357 (198–431) days following the initially-reported SARS-CoV-2 infection. Among the 380 patients who reported persistent symptoms at the time of SARS-CoV-2 vaccination, 201 (52.8%) reported a global effect on symptoms following the injection, corresponding to an improvement in 21.8% and a worsening in 31%. There were no differences based on the type of vaccine used. After a complete vaccination scheme, 93.3% (28/30) of initially seronegative patients reported a positive anti-SARS-CoV-2 IgG. A total of 170 PASC patients had not been vaccinated. The most common reasons for postponing the SARS-CoV-2 vaccine were fear of worsening PASC symptoms (55.9%) and the belief that vaccination was contraindicated because of PASC (15.6%). Conclusion: Our study suggests that SARS-CoV-2 vaccination is well tolerated in the majority of PASC patients and has good immunogenicity. Disseminating these reassuring data might prove crucial to increasing vaccine coverage in patients with PASC.


2021 ◽  
Author(s):  
Kathryn A Ryan ◽  
Robert J Watson ◽  
Kevin R Bewley ◽  
Christopher A Burton ◽  
Oliver Carnell ◽  
...  

The mutation profile of the SARS-CoV-2 Omicron variant poses a concern for naturally acquired and vaccine-induced immunity. We investigated the ability of prior infection with an early SARS-CoV-2, 99.99% identical to Wuhan-Hu-1, to protect against disease caused by the Omicron variant. We established that infection with Omicron in naive Syrian hamsters resulted in a less severe disease than a comparable dose of prototype SARS-CoV-2 (Australia/VIC01/2020), with fewer clinical signs and less weight loss. We present data to show that these clinical observations were almost absent in convalescent hamsters challenged with the same dose of Omicron 50 days after an initial infection with Australia/VIC01/2020. The data provide evidence for immunity raised against prototype SARS-CoV-2 being protective against Omicron in the Syrian hamster model. Further investigation is required to conclusively determine whether Omicron is less pathogenic in Syrian hamsters and whether this is predictive of pathogenicity in humans.


Author(s):  
Maimonah Alghanmi ◽  
Aziza Alrafiah

Background: Despite all treatment and control efforts, schistosomiasis still thrives in humanity. It is endemic in 78 countries that are anchored by poverty and diseases. Until now, the broad-spectrum praziquantel (PZQ) drug is the only effective treatment of choice. However, reports documented some side effects for PZQ like haemorrhage in lung tissues, resistance, and inefficacy to treat fibrotic tissues. Therefore, alternative drugs that help in reducing the undesired effects of schistosomiasis are required. This study examined the efficacy of Silymarin in interfering with the fibrogenesis process using a mouse model. Silymarin is a herbal extract known to have flavonoids and polyphenols that help in reducing the inflammatory reaction, stimulating hepatocyte regeneration, and inhibiting the fibrogenesis process. Methods: A total of thirty adult tBALB/c male mice were divided into negative, chronically infected control and treated groups. All were killed after 18 weeks from the initial infection. Different histopathological investigations and liver function tests were carried out to detect the difference between the groups. Results: Administration of Silymarin exhibited a significant improvement in all associated histopathology with a considerable decline in the area percentage of collagen fibers. It restored the elevated level of serum ALT as well. Conclusion: Silymarin as a treatment for chronic hepatopathies will only be successful if started during the acute phase of the disease.


2021 ◽  
Author(s):  
Sarena Banu ◽  
Mohammed M Idris ◽  
Ramakrishnan Nagaraj

Infection with the SARS-CoV-2 virus results in manifestation of several clinical observations from asymptomatic to multi-organ failure. Biochemically, the serious effects are due to what is described as cytokine storm. The initial infection region for COVID-19 is the nasopharyngeal/oropharyngeal region which is the site where samples are taken to examine the presence of virus. We have earlier shown that several defensin genes are down regulated in cells from this region in patients who tested positive in the RTPCR test. We have now carried out detailed proteomic analysis of the nasopharyngeal/oropharyngeal swab samples collected from normal individuals and those tested positive for SARS-CoV-2 by RTPCR, involving high throughput quantitative proteomics analysis. Several proteins like annexins, cytokines and histones were found differentially regulated in the host human cells following SARS-CoV-2 infection. Genes for these proteins were also observed to be differentially regulated when their expression was analyzed. Majority of the cytokine proteins were found to be up regulated in the infected individuals. Cell to Cell signaling interaction, Immune cell trafficking and inflammatory response pathways were found associated with the differentially regulated proteins based on network pathway analysis.


2021 ◽  
Vol 23 (2) ◽  
pp. 201-205
Author(s):  
Murilo Soares Costa ◽  
Gabriel de Oliveira Gelape ◽  
André Barbosa de Andrade ◽  
Luiza Passini Vaz-Tostes ◽  
Madara da Silva Simões ◽  
...  

Vaccination against COVID-19 is happening worldwide, with most vaccines requiring 2 doses to reach its maximum potential. It is the most efficient measure to prevent new cases of COVID-19, both of infection and reinfection. This case reports the reinfection of a female receptionist at an urgent care facility, where the research group was testing and monitoring symptoms of patients with flu syndrome, in the city of Belo Horizonte, Minas Gerais, Brasil, where she reinfected between the two preconized doses. Her initial infection occurred in September 2020 and reinfection in February 2021, 14 days after the first dose - both confirmed by RT-PCR - with reportedly worse symptoms on the latter. We warn for the possibility of reinfection episodes even after the first dose of vaccination, differently from what literature stated so far, so that health agents can organize more effective security measures, in a context of viral mutation and of new strains.


2021 ◽  
Vol 8 ◽  
Author(s):  
Daniel Gussarow ◽  
Agnes Bonifacius ◽  
Anne Cossmann ◽  
Metodi V. Stankov ◽  
Philip Mausberg ◽  
...  

Since its declaration as a pandemic in March 2020, SARS-CoV-2 has infected more than 217 million people worldwide and despite mild disease in the majority of the cases, more than 4.5 million cases of COVID-19-associated death have been reported as of September 2021. The question whether recovery from COVID-19 results in prevention of reinfection can be answered with a “no” since cases of reinfections have been reported. The more important question is whether during SARS-CoV-2 infection, a protective immunity is built and maintained afterwards in a way which protects from possibly severe courses of disease in case of a reinfection. A similar question arises with respect to vaccination: as of September 2021, globally, more than 5.2 billion doses of vaccines have been administered. Therefore, it is of utmost importance to study the cellular and humoral immunity toward SARS-CoV-2 in a longitudinal manner. In this study, reconvalescent COVID-19 patients have been followed up for more than 1 year after SARS-CoV-2 infection to characterize in detail the long-term humoral as well as cellular immunity. Both SARS-CoV-2-specific T cells and antibodies could be detected for a period of more than 1 year after infection, indicating that the immune protection established during initial infection is maintained and might possibly protect from severe disease in case of reinfection or infection with novel emerging variants. Moreover, these data demonstrate the opportunity for immunotherapy of hospitalized COVID-19 patients via adoptive transfer of functional antiviral T cells isolated from reconvalescent individuals.


PLoS ONE ◽  
2021 ◽  
Vol 16 (11) ◽  
pp. e0260038
Author(s):  
Caroline J. Zeiss ◽  
Jennifer L. Asher ◽  
Brent Vander Wyk ◽  
Heather G. Allore ◽  
Susan R. Compton

At present, global immunity to SARS-CoV-2 resides within a heterogeneous combination of susceptible, naturally infected and vaccinated individuals. The extent to which viral shedding and transmission occurs on re-exposure to SARS-CoV-2 is an important determinant of the rate at which COVID-19 achieves endemic stability. We used Sialodacryoadenitis Virus (SDAV) in rats to model the extent to which immune protection afforded by prior natural infection via high risk (inoculation; direct contact) or low risk (fomite) exposure, or by vaccination, influenced viral shedding and transmission on re-exposure. On initial infection, we confirmed that amount, duration and consistency of viral shedding, and seroconversion rates were correlated with exposure risk. Animals were reinfected after 3.7–5.5 months using the same exposure paradigm. 59% of seropositive animals shed virus, although at lower amounts. Previously exposed seropositive reinfected animals were able to transmit virus to 25% of naive recipient rats after 24-hour exposure by direct contact. Rats vaccinated intranasally with a related virus (Parker’s Rat Coronavirus) were able to transmit SDAV to only 4.7% of naive animals after a 7-day direct contact exposure, despite comparable viral shedding. Cycle threshold values associated with transmission in both groups ranged from 29–36 cycles. Observed shedding was not a prerequisite for transmission. Results indicate that low-level shedding in both naturally infected and vaccinated seropositive animals can propagate infection in susceptible individuals. Extrapolated to COVID-19, our results suggest that continued propagation of SARS-CoV-2 by seropositive previously infected or vaccinated individuals is possible.


mBio ◽  
2021 ◽  
Author(s):  
Danielle Westhoff Smith ◽  
Adityarup Chakravorty ◽  
Mitch Hayes ◽  
Wolfgang Hammerschmidt ◽  
Bill Sugden

Epstein-Barr virus (EBV) is a ubiquitous human pathogen, infecting up to 95% of the world’s adult population. Initial infection with EBV can cause infectious mononucleosis.


2021 ◽  
Vol 17 (11) ◽  
pp. e1010068
Author(s):  
Thomas Bruun Rasmussen ◽  
Jannik Fonager ◽  
Charlotte Sværke Jørgensen ◽  
Ria Lassaunière ◽  
Anne Sofie Hammer ◽  
...  

Mink, on a farm with about 15,000 animals, became infected with SARS-CoV-2. Over 75% of tested animals were positive for SARS-CoV-2 RNA in throat swabs and 100% of tested animals were seropositive. The virus responsible had a deletion of nucleotides encoding residues H69 and V70 within the spike protein gene as well as the A22920T mutation, resulting in the Y453F substitution within this protein, seen previously in mink. The infected mink recovered and after free-testing of 300 mink (a level giving 93% confidence of detecting a 1% prevalence), the animals remained seropositive. During further follow-up studies, after a period of more than 2 months without any virus detection, over 75% of tested animals again scored positive for SARS-CoV-2 RNA. Whole genome sequencing showed that the viruses circulating during this re-infection were most closely related to those identified in the first outbreak on this farm but additional sequence changes had occurred. Animals had much higher levels of anti-SARS-CoV-2 antibodies in serum samples after the second round of infection than at free-testing or during recovery from initial infection, consistent with a boosted immune response. Thus, it was concluded that following recovery from an initial infection, seropositive mink were readily re-infected by SARS-CoV-2.


2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Jacinda K. Dariotis ◽  
Stephanie M. Sloane ◽  
Rebecca Lee Smith

Abstract Background Severe acute respiratory syndrome coronavirus 2 reinfection prevalence is unknown. It is essential to understand reinfection symptoms and, importantly, the lived experience. Case presentation Case study design is the best method for understanding this contemporary pandemic and rare occurrence of reinfections. A 19-year-old White Non-Hispanic woman presented with presumed severe acute respiratory syndrome coronavirus 2 reinfection 6 weeks after initially mild symptomatic infection and consistent repeat negative results. Real-time reverse-transcription polymerase chain reaction from saliva was used for detection. Twice-weekly saliva samples were collected (a) before initial infection, (b) resumed on day 10 after initial infection until reinfection was detected, and (c) resumed on day 10 post-reinfection. A 1.5-hour virtual interview was conducted, transcribed, and independently analyzed by two researchers. Four themes emerged: (1) perceived invincibility or inevitability and subsequent immunity increases risk of transmission via inconsistent preventive behaviors; (2) normalcy desires, trusted others, and implicit social pressures to not wear masks and distance increase one’s coronavirus disease 2019 risk; (3) physical symptoms are more severe with reinfection compared with first infection; and (4) mental health sequelae (trauma and stigma) are more severe and enduring than physical health outcomes. Conclusions Unmasked social interactions contradicting public health recommendations were rationalized by social circle members with heavy reliance on feeling asymptomatic, lacking a positive test (testing negative or not testing), or attributing symptoms to allergies. Stigma of testing positive and consequences of not conforming to social group behaviors is overwhelming and creates pressure to take risks. This case study provides insights and lessons learned relevant for public health messaging and continued preventive behaviors.


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