Infections, inflammation, and risk of neuropsychiatric disorders: the neglected role of �co-infection�

Neuropsychiatric disorders (NPDs) have multiple etiological factors, mainly genetic background, environmental conditions and immunological factors. The host immune responses play a pivotal role in various physiological and pathophysiological process. In NPDs, inflammatory immune responses have shown to be involved in diseases severity and treatment outcome. Inflammatory cytokines and chemokines are involved in various neurobiological pathways, such as GABAergic signaling and neurotransmitter synthesis. Infectious agents are among the major amplifier of inflammatory reactions, hence, have an indirect role in the pathogenesis of NPDs. As such, some infections directly affect the central nervous system (CNS) and alter the genes that involved in neurobiological pathways and NPDs. Interestingly, the most of infectious agents that involved in NPDs (e.g., Toxoplasma gondii, cytomegalovirus and herpes simplex virus) is latent (asymptomatic) and co-or-multiple infection of them are common. Nonetheless, the role of co-or-multiple infection in the pathogenesis of NPDs has not deeply investigated. Evidences indicate that co-or-multiple infection synergically augment the level of inflammatory reactions and have more severe outcomes than single infection. Hence, it is plausible that co-or-multiple infections can increase the risk and/or pathogenesis of NPDs. Further understanding about the role of co-or-multiple infections can offer new insights about the etiology, treatment and prevention of NPDs. Likewise, therapy based on anti-infective and anti-inflammatory agents could be a promising therapeutic option as an adjuvant for treatment of NPDs. © 2020 Infection; Inflammation; Neuropsychiatric disorders; Co-infection; Immunology; Microbiology; Infectious disease; Psychiatry. © 202

Transmission routes for SARS-CoV-2 infection: review of evidence

There is no specific treatment for SARS-CoV-2, and all infection control strategies are based on breaking the transmission chain of virus. The high transmission rate of SARS-CoV-2 has raised many questions about the possible routes of infection transmission. Due to uncertainty of the main transmission routes, the infection control policies faced with more challenges. The possible main route of transmission is thought to be the close contact and respiratory droplets. Therefore, it is necessary to maintain physical distance and using the face mask. Another routes of transmission are through contaminated surfaces as well as airborne, fecal-oral transmission

Host factors and vaccine efficacy: Implications for COVID-19 vaccines

The efficacy of the vaccines varies between individuals and populations. The immunogenicity of the vaccine is influenced by various factors, including host factors. Previous studies have shown that host factors affect the effectiveness of vaccines, which may be true about COVID-19 vaccines. In this review, we evaluate the possible association of host factors with vaccine efficacy with a special focus on COVID-19 vaccines

Claims and reasons about mild COVID-19 in children

The elderly form the main risk group in the coronavirus disease 2019 (COVID-19) pandemic, and age is recognized as a major risk factor for the severity of infection and mortality of COVID-19. The severity of the infection in children is milder than in adults. Although the pathophysiology of COVID-19 is not fully understood, several possible factors and mechanisms have been suggested for the lower severity of infection in children. (c) 2021 The Author(s). Published by Elsevier Ltd

COVID-19 reinfection: prolonged shedding or true reinfection?

The SARS-CoV-2 pandemic is underway and millions of people have been infected. A large number of patients with COVID-19 have recovered and been discharged. While a number of recovered patients test positive again or even have a recurrence of clinical symptoms. Some researchers believe that a positive retest is related to the long-term persistence of the virus in the body, although there is some evidence in favor of reinfection. In this study, we focus more on the possible reasons for positive retesting, antibody responses, and review of possible reinfection case reports

COVID-19-associated opportunistic infections: a snapshot on the current reports

Treatment of the novel Coronavirus Disease 2019 (COVID-19) remains a complicated challenge, especially among patients with severe disease. In recent studies, immunosuppressive therapy has shown promising results for control of the cytokine storm syndrome (CSS) in severe cases of COVID-19. However, it is well documented that immunosuppressive agents (e.g., corticosteroids and cytokine blockers) increase the risk of opportunistic infections. On the other hand, several opportunistic infections were reported in COVID-19 patients, including Aspergillus spp., Candida spp., Cryptococcus neoformans, Pneumocystis jiroveci (carinii), mucormycosis, Cytomegalovirus (CMV), Herpes simplex virus (HSV), Strongyloides stercoralis, Mycobacterium tuberculosis, and Toxoplasma gondii. This review is a snapshot about the main opportunistic infections that reported among COVID-19 patients. As such, we summarized information about the main immunosuppressive agents that were used in recent clinical trials for COVID-19 patients and the risk of opportunistic infections following these treatments. We also discussed about the main challenges regarding diagnosis and treatment of COVID-19-associated opportunistic infections (CAOIs)

An update review on complicated mechanisms of COVID-19 pathogenesis and therapy: direct viral damage, renin-angiotensin system dysregulation, immune system derangements, and endothelial dysfunction

SARS-CoV-2 was reported as the cause of coronavirus disease 2019 (COVID-19) in late December 2019. The new virus belongs to the Coronaviridae family and the Betacoronavirus genus, according to sequencing and phylogenetic studies. Genomic sequence analysis showed that SARS-CoV-2 is similar to SARS. SARS-CoV-2 is more infectious and the high level of COVID-19 community transmission has led to a growing pandemic. Although infections in most patients with COVID-19 are moderate or mild, 20 of the patients develop severe or critical disease. COVID- 19 may affect a wide range of organs and tissues, including respiratory, digestive system, nervous system, and skin. Patients with COVID-10 have been confirmed to have renal, cardiovascular, gastrointestinal, and nervous system problems in addition to pulmonary involvement. The pathogenesis of SARS-CoV-2 is being investigated, but it is possible that the organ damage might in part be caused by direct viral damage (detection of inclusion bodies in tissues, such as the kidneys), dysregulation of the immune system, renin-angiotensin system, bradykinin pathway, and coagulation, as well as host genetic factors and their polymorphisms, which may affect the disease severity. In this review, an update on the possible pathogenesis pathways of COVID-19 has been performed. It is hoped that best care is developed for patients with COVID- 19 by identifying its pathogenesis pathways

Host factors and vaccine efficacy: Implications for COVID-19 vaccines

The efficacy of the vaccines varies between individuals and populations. The immunogenicity of the vaccine is influenced by various factors, including host factors. Previous studies have shown that host factors affect the effectiveness of vaccines, which may be true about COVID-19 vaccines. In this review, we evaluate the possible association of host factors with vaccine efficacy with a special focus on COVID-19 vaccines