Effects of vaccination, new SARS-CoV-2 variants and reinfections on post-COVID-19 complications

Long COVID or Post-COVID-19 Condition: Past, Present and Future Research Directions

The presence of symptoms after an acute SARS-CoV-2 infection (long-COVID) has become a worldwide healthcare emergency but remains underestimated and undertreated due to a lack of recognition of the condition and knowledge of the underlying mechanisms. In fact, the prevalence of post-COVID symptoms ranges from 50% during the first months after the infection up to 20% two-years after. This perspective review aimed to map the existing literature on post-COVID symptoms and to identify gaps in the literature to guide the global effort toward an improved understanding of long-COVID and suggest future research directions. There is a plethora of symptomatology that can be due to COVID-19; however, today, there is no clear classification and definition of this condition, termed long-COVID or post-COVID-19 condition. The heterogeneity in the symptomatology has led to the presence of groups/clusters of patients, which could exhibit different risk factors and different mechanisms. Viral persistence, long-lasting inflammation, immune dysregulation, autoimmune reactions, reactivation of latent infections, endothelial dysfunction and alteration in gut microbiota have been proposed as potential mechanisms explaining the complexity of long-COVID. In such an equation, viral biology (e.g., re-infections, SARS-CoV-2 variants), host biology (e.g., genetics, epigenetics) and external factors (e.g., vaccination) should be also considered. These various factors will be discussed in the current perspective review and future directions suggested.

Neuropsychiatric post-acute sequelae of COVID-19: prevalence, severity, and impact of vaccination

The potential long-term neuropsychiatric effects of COVID-19 are of global concern. This study aimed to determine the prevalence and predictors of neuropsychiatric post-acute sequelae of COVID-19 among Egyptian COVID-19 survivors and to study the impact of full vaccination before COVID-19 infection on the occurrence and severity of these manifestations. Three months after getting COVID-19 infection, 1638 COVID-19 survivors were screened by phone for possible neuropsychiatric sequelae. Subjects suspected to suffer from these sequelae were invited to a face-to-face interview for objective evaluation. They were requested to rate the severity of their symptoms using visual analogue scales (VAS). The mean age of participants was 38.28 ± 13 years. Only 18.6% were fully vaccinated before COVID-19 infection. Neuropsychiatric post-acute sequelae of COVID-19 were documented in 598 (36.5%) subjects, fatigue was the most frequent one (24.6%), followed by insomnia (16.4%), depression (15.3%), and anxiety (14.4%). Moderate and severe COVID-19 infection and non-vaccination increased the odds of developing post-COVID-19 neuropsychiatric manifestations by 2 times (OR 1.95, 95% CI = 1.415-2.683), 3.86 times (OR 3.86, 95% CI = 2.358-6.329), and 1.67 times (OR 1.67, 95% CI = 1.253-2.216), respectively. Fully vaccinated subjects before COVID-19 infection (n = 304) had significantly lesser severity of post-COVID-19 fatigue, ageusia/hypogeusia, dizziness, tinnitus, and insomnia (P value = 0.001, 0.008, < 0.001, 0.025, and 0.005, respectively) than non-vaccinated subjects. This report declared neuropsychiatric sequelae in 36.5% of Egyptian COVID-19 survivors, fatigue being the most prevalent. The effectiveness of COVID-19 vaccines in reducing the severity of some post-COVID-19 neuropsychiatric manifestations may improve general vaccine acceptance.

SARS-CoV-2 Reinfections and Long COVID in the Post-Omicron Phase of the Pandemic

We are reviewing the current state of knowledge on the virological and immunological correlates of long COVID, focusing on recent evidence for the possible association between the increasing number of SARS-CoV-2 reinfections and the parallel pandemic of long COVID. The severity of reinfections largely depends on the severity of the initial episode; in turn, this is determined both by a combination of genetic factors, particularly related to the innate immune response, and by the pathogenicity of the specific variant, especially its ability to infect and induce syncytia formation at the lower respiratory tract. The cumulative risk of long COVID as well as of various cardiac, pulmonary, or neurological complications increases proportionally to the number of SARS-CoV-2 infections, primarily in the elderly. Therefore, the number of long COVID cases is expected to remain high in the future. Reinfections apparently increase the likelihood of long COVID, but less so if they are mild or asymptomatic as in children and adolescents. Strategies to prevent SARS-CoV-2 reinfections are urgently needed, primarily among older adults who have a higher burden of comorbidities. Follow-up studies using an established case definition and precise diagnostic criteria of long COVID in people with or without reinfection may further elucidate the contribution of SARS-CoV-2 reinfections to the long COVID burden. Although accumulating evidence supports vaccination, both before and after the SARS-CoV-2 infection, as a preventive strategy to reduce the risk of long COVID, more robust comparative observational studies, including randomized trials, are needed to provide conclusive evidence of the effectiveness of vaccination in preventing or mitigating long COVID in all age groups. Thankfully, answers not only on the prevention, but also on treatment options and rates of recovery from long COVID are gradually starting to emerge.

The prevalence of and factors related to reinfection with COVID-19 in Ahvaz, Iran: A comparative cross-sectional study

Background and Aims

Reinfection with the coronavirus disease 2019 (COVID-19) virus may be as serious as the first infection, exposing people to risks such as admission to hospital or even death. This study aimed to evaluate the prevalence of and the factors related to reinfection in Ahvaz, Iran.

Methods

This was a comparative cross-sectional study that was conducted on 200 reinfected individuals and 200 people who had once been infected with COVID-19. Infection with COVID-19 was confirmed using the polymerase chain reaction (PCR) test, and those with reinfection had to have a negative PCR test after recovery from the first infection and a positive PCR test for COVID-19 > 90 days after the first infection. Data was collected using a questionnaire and a checklist. Data were analyzed using the Chi-square test, independent t-test, and logistic regression test.

Results

Around 7000 reinfections were observed in this study, and the prevalence of reinfection was 0.59% in Ahvaz City. A large proportion of the participants in the control group, 133 (66.5%) received two doses of COVID-19 vaccines compared with 110 (55%) in the reinfected group (p = 0.003), and 43 (21.5%) of reinfected participants did not receive any vaccine. Older people were 0.982 times more likely to get reinfected with COVID-19 (95% confidence interval [CI]: 0.966-0.997). Also, those receiving vaccination once or twice were 2.311 and 2.498 times less likely to get reinfected with COVID-19, respectively (95% CI: 1.093-4.887 and 1.281-4.872, respectively).

Conclusion

The findings of this study showed that the prevalence of reinfection among people in Ahvaz City was 0.59%. Older individuals, those without vaccination or with suboptimal vaccination, and people with comorbidities were at a higher risk for reinfection. Health policymakers should pay more attention to factors related to reinfection with COVID-19.

Impairments following COVID-19 infection: manifestations and investigations of related factors

The COVID-19 pandemic had a major global impact on the health and wellbeing for many individuals. Even though the infection rates have gone down due to the availability of vaccines, the consequences of the disease are still present due to persistent symptoms among individuals. The aim of the current study was to map long-term impairments in individuals infected with COVID-19 by applying the framework of the World Health Organization's International Classification of Functioning, Disability and Health (ICF) and also investigate the factors related to the context of an individual's life influencing the impairments. A web-survey that targeted individuals that had been infected with COVID-19 was used. The survey included a range of measures covering contextual factors and factors related to body functions and structures and post-COVID impairments. A total of 501 individuals were included in the study (with a mean age of 47.6 years). 96% of the respondents reported at least one moderate-to-severe impairment due to COVID-19 infection and the most frequent one was fatigue. In that, 79.6% and 86.9% of the study sample reported moderate-to-severe brain fatigue and tiredness or lack of energy, respectively. Severity of COVID-19 infection appeared as the strongest risk factor for post-COVID impairments. Based on the results, interventions can be tailored to help individuals with post-COVID-19 condition. This could be one way lessening the effect of COVID-19 on health care and society as a whole.