Thymosin alpha 1 restores the immune homeostasis in lymphocytes during Post-Acute sequelae of SARS-CoV-2 infection.

The complex alterations of the immune system and the immune-mediated multiorgan injury plays a key role in host response to SARS-CoV-2 infection and in the pathogenesis of COVID-19, being also associated with adverse outcomes. Thymosin alpha 1 (Tα1) is one of the molecules used in the treatment of COVID-19, as it is known to restore the homeostasis of the immune system during infections and cancer. The use of Tα1 in COVID-19 patients had been widely used in China and in COVID-19 patients, it has been shown to decrease hospitalization rate, especially in those with greater disease severity, and reduce mortality by restoring lymphocytopenia and more specifically, depleted T cells. Persistent dysregulation with depletion of naive B and T cell subpopulations and expansion of memory T cells suggest a chronic stimulation of the immune response in individuals with post-acute sequelae of SARS-CoV-2 infection (PASC). Our data obtained from an ex vivo study, showed that in PASC individuals with a chronically altered immune response, Tα1 improve the restoration of an appropriate response, most evident in those with more severe illness and who need respiratory support during acute phase, and in those with specific systemic and psychiatric symptoms of PASC, confirming Tα1 treatment being more effective in compromised patients. The results obtained, along with promising reports on recent trials on Tα1 administration in patients with COVID-19, offer new insights into intervention also for those patients with long-lasting inflammation with post-infectious symptoms, some of which have a delayed onset.

High prevalence of asymptomatic SARS-CoV-2 infection in a cohort of liver transplant recipients in central Italy.

Asymptomatic subjects account for 25 to 45% of SARS-CoV-2 infections, and in particular, subjects on mild immunosuppressive therapy may have symptoms masked and could spread virus for an extended period of time. To determine the cumulative incidence of symptomatic and asymptomatic SARS-CoV-2 infections and associated risk factors, we conducted a prospective clinical and serological survey in a cohort of 278 liver transplant recipients (LTRs) from Central Italy. Three different serology tests were performed every 4 months in 259 LTRs between April 2020 and April 2021: one based on raw extract of whole SARS-CoV-2 virus and two on specific viral antigens (nucleoprotein and receptor binding domain) to detect specific IgG, IgM and IgA. Hundred fifteen LTRs who reported symptoms or close contact with a SARS-CoV-2-positive subject, or had a positive serological result underwent molecular testing by standard screening procedures (RT-PCR on naso-pharyngeal swab). Thirty-one past or active SARS-CoV-2 infections were identified: 14 had positive molecular test (64% symptomatic), and 17 had positive serology only (18% symptomatic). SARS-CoV-2 infection was not statistically related to gender, age, obesity, diabetes, renal impairment, type of anti-rejection therapy or time from transplant. Asymptomatic SARS-CoV-2 cases (61.3%) were more frequent in males and in those with glomerular filtrate rate >50 ml/min. Overall, the addition of repeated serology to standard diagnostic molecular protocols increased detection of SARS-CoV-2 infection from 5.1% to 10.9%. Anti-SARS-CoV-2 seroprevalence among our LTRs (11.2%) is comparable to the general population of Central Italy, considered a medium-impact area. Only one asymptomatic subject (6%) was found to carry SARS-CoV-2 in respiratory tract at the time of serological diagnosis.

Prevalence of parasitic infections in migrants: do official symptom-driven guidelines apply to the current situation?

In recent years, migration has become a significant challenge in Western countries. Migrant populations, coming from hyper-endemic areas, may present parasitic infections that remain latent and asymptomatic even for years, eventually leading to severe complications. Italian guidelines have been established to perform screening guided by the presence of symptoms and/or hypereosinophilia. Parasitological screening was conducted in a migrant population to carry out preventative measures. All migrants were asked to report any symptoms suggesting parasitic infections and list any previous treatment received. Travel data were recorded. Parasitological examination of stools and urine were conducted in all patients regardless of symptoms. In all, 208 consecutive patients were enrolled in our outpatient clinic from November 2016 to August 2017. Thirty-four patients were excluded due to the previous assumption of albendazole or because they did not exhibit suitable samples. Prevalence of parasitic infections was 33/174 (18.9%). A statistically significant difference for the prevalence of parasitic infections was not found between patients who were asymptomatic and without hypereosinophilia compared to those who presented symptoms and/or hypereosinophilia (27/151 [17.9%] vs. 6/23 [26.0%]; p=0.39). By contrast, a statistically significant difference was found for the length of time between arrival in Italy and parasitological examinations (4/51 [7.8%] migrants who arrived in Italy more than six months prior to screening vs. 29/123 [23.6%] migrants who arrived within six months; p= 0.016). Our results did not demonstrate any significant differences in prevalence of parasitic infections between symptomatic or hypereosinophilic and asymptomatic migrants. Thus we feel it inappropriate to support recent guidelines recommending parasitological examinations only in migrants with symptoms and/or hypereosinophilia. By contrast, it would appear important to perform parasitological screening in migrants as soon as possible after their arrival. Since such infestations, if untreated, could result in chronic diseases and complications, and could be transmitted in the host countries, our results have potential implications for public health.