ABSTRACT
Long COVID, in which disease-related symptoms persist for months after recovery, has led to a revival of the discussion of whether neuropsychiatric long-term symptoms after viral infections indeed result from virulent activity or are purely psychological phenomena. In this review, we demonstrate that, despite showing differences in structure and targeting, many viruses have highly similar neuropsychiatric effects on the host. Herein, we compare severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), human immunodeficiency virus 1 (HIV-1), Ebola virus disease (EVD), and herpes simplex virus 1 (HSV-1). We provide evidence that the mutual symptoms of acute and long-term anxiety, depression and post-traumatic stress among these viral infections are likely to result from primary viral activity, thus suggesting that these viruses share neuroinvasive strategies in common. Moreover, it appears that secondary induced environmental stress can lead to the emergence of psychopathologies and increased susceptibility to viral (re)infection in infected individuals. We hypothesize that a positive feedback loop of virus-environment-reinforced systemic responses exists. It is surmised that this cycle of primary virulent activity and secondary stress-induced reactivation, may be detrimental to infected individuals by maintaining and reinforcing the host's immunocompromised state of chronic inflammation, immunological strain, and maladaptive central-nervous-system activity. We propose that this state can lead to perturbed cognitive processing and promote aversive learning, which may manifest as acute, long-term neuropsychiatric illness.
ABSTRACT
Introduction: COVID-19 pandemic has affected the whole world. Besides COVID, other viral infections may emerge during the course of the disease owing to lymphopenia, use of immunosuppressants, underlying comorbidities, and immune dysregulation, which may pose additional threats.1 We hereby describe two cases of COVID- 19 with viral co-infections belonging to the Herpesviridae family with undulating clinical course. Case 1: Cytomegalovirus (CMV) Co-infection: A 55-year-old male, COVID unvaccinated, chronic smoker, overweight and hypertensive was admitted to our ICU with a 1-week history of fever, cough, and breathlessness. SARSCoV- 2 reverse transcriptase-polymerase chain reaction (RT-PCR) test was positive. At admission, he had hypoxaemia (SpO2 86%on room air), respiratory rate 35-40/minute, and ground-glass opacities in chest X-ray involving 50% of bilateral lung parenchyma suggestive of severe COVID-19 pneumonia. He was managed with lung-protective invasive mechanical ventilation, restrictive fluid strategy, 16-18 hour/day proning sessions (4-5), intravenous (IV) remdesivir, IV dexamethasone 6 mg 12 hourly, and enoxaparin thromboprophylaxis. After 2 weeks of ICU stay, weaning was attempted but the weaning attempts failed due to underlying neuromuscular weakness. On examination, bilateral (B/L) cranial nerve palsies, areflexia, and motor power 0/5 in bilateral upper and lower limbs were noticed. possibility of Guillain-Barre syndrome (GBS) was kept and IV immunoglobulin therapy was empirically administered for 5 days with some improvement in power up to 1/5 in upper limbs. On day 35 of hospitalization, he developed pancytopenia along with features of deranged liver function and gut dysfunction. In evaluation, PCR for CMV turned out to be positive in blood. Bone marrow aspiration and biopsy showed hemopoiesis with viral inclusion bodies and hemophagocytosis (HLH) [Figs 1 and 2]. A diagnosis of secondary HLH related to CMV was contemplated and IV ganciclovir was initiated along with steroids. Histological evidence of CMV co-infection was present and moreover, the quantitative viral load of CMV showed a decreasing trend after initiating IV gancyclovir. However, the patient continued to deteriorate and succumbed to his illness in the 8th week of the ICU stay. Case 2: Herpes Simplex Virus (HSV) Co-infection: Twenty-three years postpartum female with no comorbidities and uneventful obstetric history was referred to our hospital two weeks after a full-term normal vaginal delivery. She developed generalized status epilepticus on the 10th day of delivery, which was managed with anti-epileptic drugs (AEDs). During the hospital stay, RTPCR for COVID-19 turned out to be positive but she remained asymptomatic and seizures were well-controlled on AEDs. On admission to our hospital, she was fully conscious and alert with no neurological deficits. Notable findings were pancytopenia with megaloblastic features, B/L pedal edema, and hepatosplenomegaly. NCCT brain revealed mild subarachnoid hemorrhage (SAH) along the bilateral parietooccipital region for which conservative management was planned. 2D echocardiography was normal. Ultrasonography of the abdomen showed gross splenomegaly and mild hepatomegaly with mesenteric lymphadenopathy. NCCT thorax and abdomen were unremarkable apart from hepatosplenomegaly. In pancytopenia workup, IgM anti-HSV-1 antibodies turned out to be positive in blood. In addition, tropical workup was suggestive of Leptospirosis (IgM antibodies positive). Serological evidence was suggestive of acute HSV-1 infection (based on antibody titers). Bone marrow workup had features of trilineage hematopoiesis with micronormoblastic maturation consistent with iron deficiency anemia without any evidence of hemophagocytosis. IV acyclovir, IV doxycycline, and iron replacement were added, after which she improved clinically and was discharged in stable condition. Tables 1 and 2 show a detailed description of these cases. Discussion: Herpesviridae family is the most important group of viruses responsible for persistent vi al infections in humans, of which CMV contributes to 60-90% of infections in adults, especially in developing countries.2 In healthy individuals, these viruses are kept dormant by the body's immune mechanisms but in an immunocompromised population, reactivation from the latent state can occur. SARS-CoV-2 infection predisposes patients to concomitant viral co-infections, owing to T-cell lymphopenia, decreased NK cell number, and use of immunosuppressive medications.3,4 The first case of CMV co-infection was first reported by D'Ardes and co-workers in 2020.5 Since then, many studies have been emerging in this area. In an observational study from France, 38 COVID-19 patients on >7 days of MV were studied for HSV and CMV pulmonary co-infections (by quantitative real-time PCR in tracheal samples) out of which 47% of patients had one of these infections (24% HSV, 5% CMV, 18% both).6 Another study looking for HSV-1 in patients on invasive MV found HSV-1 reactivation between days 11 and 40, which correlated with immunological markers of decreased innate immunity.7 A case series looking for CMV infection (by PCR in plasma or BAL) in COVID-19, also found CMV reactivation between day 7 and 45 of illness. Most of these patients were above 60 years of age and immunosuppressed (HIV, diabetes mellitus, medications).8 Although immunocompromised individuals are more vulnerable, healthy immunocompetent adults who are critically ill or on prolonged MV may also be susceptible to these infections.9-12 This may be explained by a state of immunoparalysis inherent to prolonged critical illness. In case 1, an ICU stay of around 9 weeks complicated with recurrent nosocomial infections, multiple blood product transfusions, and steroid usage could have the likely triggers. Whether viral co-infections are merely bystanders or truly pathogenic is difficult to comment but timely management is essential to avoid end-organ damage (EOD) which may occur directly (by enhanced viral load secondary to compromised host immunity) or indirectly (by inflammatory changes consequent to prolonged cell-mediated immunity required to maintain viral dormancy).2-4,13 It also seems imperative to study if a viral co-infection has a proclivity to develop more severe hematological anomalies (besides the inherent risk of HLH with COVID) as was seen in case 1, in which the patient had a downward spiral of illness with multiorgan dysfunction.14-15 Limitations: Dynamics of PCR trends and virology studies of samples from trachea, gut, and urine could not be analysed in our patients. Conclusion: Viral co-infections can occur in COVID-19 disease as these patients are often immunocompromised and critically ill. A high index of suspicion and prompt management is needed to improve the outcome of patients. Patients with organ dysfunctions especially hematologic abnormalities with bone marrow involvement should be worked up in detail to look for concomitant viral co-infections. In the future, large-scale research is needed to better elucidate the relationship between SARS-CoV-2 and other viral co-infections.
ABSTRACT
Objective: The coronavirus disease 2019 (COVID-19) epidemic resulting from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has still spread globally. The occurrence of the Delta variant, which is more infectious and spreads faster than earlier forms of the virus that causes COVID-19, makes infection prevention more challenging. Therefore, this study aimed to gain a comprehensive insight into the transmission routes of SARS-CoV-2 for curbing the propagation of SARS-CoV-2 in human populations. Methods: We studied a prospective cohort of 576 patients admitted consecutively to the First Affiliated Hospital of Guangzhou Medical University from January 21 to June 8, 2020. These patients were chosen based on their similar clinical phenotypes or imaging findings. There were 21 (3.6%) laboratory-confirmed COVID-19 patients (16 severe and 5 mild cases) and 555 non-COVID-19 patients. The antibody response and routes and duration of viral shedding were systematically evaluated in serial clinical specimens. Moreover, SARS-CoV-2 RNA was also detected in a mouth rinse, urine, and tear samples. This study was approved by the Medical Ethical Committee of The First Affiliated Hospital of Guangzhou Medical University (approval No. 2020-77). Results: SARS-CoV-2 mainly existed in sputum, nasal and throat swabs, and feces samples. Virus latency was longer in sputum and feces samples than in nasopharyngeal samples. IgG antibody response in respiratory samples was related to disease severity. Although droplets and aerosols are the major transmission routes for COVID-19, covert routes of transmission from asymptomatic patients, contaminated surfaces, and wastewater are also of interest. Conclusion: Our findings provide a solid foundation for developing prophylactic measures against SARS-CoV-2.