Early administration of nirmatrelvir/ritonavir leads to faster negative SARS-CoV-2 nasal swabs than monoclonal antibodies in COVID 19 patients at high-risk for severe disease.

PURPOSE: Besides the well-established efficacy in preventing severe COVID-19, the impact of early treatments, namely antivirals and monoclonal antibodies (mAbs), on the time length to negativization of SARS-CoV-2 nasal swabs is still unclear. The aim of this study was to compare the efficacy of different early treatments in reducing the SARS-CoV-2 viral shedding, identifying a single drug that might potentially lead to a more rapid negativization of SARS-CoV-2 nasal swab. METHODS: This was a single-centre, retrospective, observational study conducted at Ospedale Luigi Sacco in Milan. Data of high-risk COVID-19 patients who received early treatments between 23 December 2021 and March 2023 were extracted. The comparison across treatments was conducted using the Kruskall-Wallis test for continuous variables. Dunn's test with Bonferroni adjustment was performed for post-hoc comparisons of days to negativization. Secondly, a negative binomial regression adjusted for age, sex, number of comorbidities, immunosuppression, and SARS-CoV-2 vaccination status was implemented. RESULTS: Data from 428 patients receiving early treatments were collected. The majority were treated with Nirmatrelvir/Ritonavir and were affected by SARS-CoV-2 Omicron infection with BA.2 sublineage. The median length time to SARS-CoV-2 nasal swab negativization was 9 days [IQR 7-13 days]. We found that Nirmatrelvir/Ritonavir determined a significant decrease of the length time to SARS-CoV-2 nasal swab negativization compared to mAbs (p = 0.003), but not compared to Remdesivir (p = 0.147) and Molnupiravir (p = 0.156). CONCLUSION: Our findings highlight the importance of promptly treating high-risk COVID-19 patients with Nirmatrelvir/Ritonavir, as it also contributes to achieving a faster time to negative SARS-CoV-2 nasal swabs.

Delayed diagnosis among patients with visceral leishmaniasis.

We aimed to estimate the diagnostic latency of patients with visceral leishmaniasis (VL). A monocentric retrospective observational study was conducted including all confirmed cases of VL diagnosed from January 2005 to March 2022. Epidemiological and clinical characteristics of patients with VL were collected. The diagnostic latency was defined as the number of days between the first contact with a health-care provider for signs and/or symptoms referable to VL and the laboratory diagnosis of leishmaniasis. Twenty-four cases of VL were included in the study, mostly male (75%) and Italians (79.2%), with a median age of 40 years [Inter Quartile Range (IQR 30-48)]. Fourteen (58.3%) VL cases were people living with HIV (PLWH) and 4 (16.6%) subjects were on immunosuppressive therapy. For VL the median diagnostic latency was 54 days (IQR 28-162). The shorter diagnostic latency was observed in PLWH [31 days (IQR 20-47)] followed by immunocompetent patients [160 days (IQR 133-247)] and those on immunosuppressive therapy [329 days (IQR 200-678)]. Twelve patients (50%) reported at least one medical encounter before the diagnosis of VL and 6 patients received a wrong therapy. Diagnostic delay in VL was significant in patients under immune suppressive treatment.

The Defenders of the Alveolus Succumb in COVID-19 Pneumonia to SARS-CoV-2 and Necroptosis, Pyroptosis, and PANoptosis.

Alveolar type II (ATII) pneumocytes as defenders of the alveolus are critical to repairing lung injury. We investigated the ATII reparative response in coronavirus disease 2019 (COVID-19) pneumonia, because the initial proliferation of ATII cells in this reparative process should provide large numbers of target cells to amplify severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus production and cytopathological effects to compromise lung repair. We show that both infected and uninfected ATII cells succumb to tumor necrosis factor-α (TNF)-induced necroptosis, Bruton tyrosine kinase (BTK)-induced pyroptosis, and a new PANoptotic hybrid form of inflammatory cell death mediated by a PANoptosomal latticework that generates distinctive COVID-19 pathologies in contiguous ATII cells. Identifying TNF and BTK as the initiators of programmed cell death and SARS-CoV-2 cytopathic effects provides a rationale for early antiviral treatment combined with inhibitors of TNF and BTK to preserve ATII cell populations, reduce programmed cell death and associated hyperinflammation, and restore functioning alveoli in COVID-19 pneumonia.

Hospitalisation for monkeypox in Milan, Italy.

During the current multi-country outbreak of human monkeypox the hospitalisation rate observed in Milan, Italy was 8.8%. Bacterial superinfection and severe perianal pain were the main cause of hospitalisation requiring antibiotic treatment and analgesic therapy. One patient was treated with Cidofovir. All hospitalised patients were discharged and the outcome was favourable with full recovery.

The Defenders of the Alveolus Succumb in COVID-19 Pneumonia to SARS-CoV-2, Necroptosis, Pyroptosis and Panoptosis.

The alveolar type II (ATII) pneumocyte has been called the defender of the alveolus because, amongst the cell’s many important roles, repair of lung injury is particularly critical. We investigated the extent to which SARS-CoV-2 infection incapacitates the ATII reparative response in fatal COVID-19 pneumonia, and describe massive infection and destruction of ATI and ATII cells. We show that both type I interferon-negative infected ATII and type I-interferon-positive uninfected ATII cells succumb to TNF-induced necroptosis, BTK-induced pyroptosis and a new PANoptotic hybrid form of inflammatory cell death that combines apoptosis, necroptosis and pyroptosis in the same cell. We locate pathway components of these cell death pathways in a PANoptosomal latticework that mediates emptying and disruption of ATII cells and destruction of cells in blood vessels associated with microthrombi. Early antiviral treatment combined with inhibitors of TNF and BTK could preserve ATII cell populations to restore lung function and reduce hyperinflammation from necroptosis, pyroptosis and panoptosis. Highlights: In fatal COVID-19 pneumonia, the initial destruction of Type II alveolar cells by SARS-CoV-2 infection is amplified by infection of the large numbers of spatially contiguous Type II cells supplied by the proliferative reparative response.Interferon-negative infected cells and interferon-positive uninfected cells succumb to inflammatory forms of cell death, TNF-induced necroptosis, BTK-induced pyroptosis, and PANoptosis.All of the cell death pathway components, including a recently identified NINJ1 component, are localized in a PANoptosome latticework that empties in distinctive patterns to generate morphologically distinguishable cell remnants.Early combination treatment with inhibitors of SARS-CoV-2 replication, TNF and BTK could reduce the losses of Type II cells and preserve a reparative response to regenerate functional alveoli.

Family cluster of Chagas disease among Bolivian immigrants in Italy: High rate of maternal-fetal transmission.

BACKGROUND: Chagas disease (CD) or American trypanosomiasis is a neglected anthropozoonosis caused by Trypanosoma cruzi that affects 6-8 million people worldwide (mainly in Latin America), 30-40% of whom develop cardiac or digestive complications. Once confined to endemic areas of Latin America, CD has more recently become a global disease as a result of migration flows from endemic to non-endemic regions, particularly in northern America and Europe. Congenital transmission is a particular challenge as it may be sustained for multiple generations and perpetuate the infection even in non-endemic countries. METHODS: Subjects were identified during a cross-sectional survey of CD among Latin American people living in Milan, Italy. Serology was carried out using tests based on either a lysate and a recombinant antigen of Trypanosoma cruzi. They were also tested by a conventional Polymerase Chain Reaction (PCR) targeting the 330 bp variable region of the T. cruzi kinetoplast minicircle genome and a commercial real-time PCR. RESULTS: We here describe a Bolivian family cluster with seven affected people with at least two autochthonous congenital T. cruzi infection which was identified during the course of a CD screening programme. We also review the epidemiology, diagnosis and control of congenital CD, with particular emphasis on the challenges facing the control and management of such a complex and still largely hidden disease. CONCLUSIONS: Our experience confirms the need to screen for CD all family members once a case is diagnosed and shows the possible high rate of congenital CD also in non-endemic areas.

A Lab-On-chip Tool for Rapid, Quantitative, and Stage-selective Diagnosis of Malaria.

Malaria remains the most important mosquito-borne infectious disease worldwide, with 229 million new cases and 409.000 deaths in 2019. The infection is caused by a protozoan parasite which attacks red blood cells by feeding on hemoglobin and transforming it into hemozoin. Despite the WHO recommendation of prompt malaria diagnosis, the quality of microscopy-based diagnosis is frequently inadequate while rapid diagnostic tests based on antigens are not quantitative and still affected by non-negligible false negative/positive results. PCR-based methods are highly performant but still not widely used in endemic areas. Here, a diagnostic tool (TMek), based on the paramagnetic properties of hemozoin nanocrystals in infected red blood cells (i-RBCs), is reported on. Exploiting the competition between gravity and magnetic forces, i-RBCs in a whole blood specimen are sorted and electrically detected in a microchip. The amplitude and time evolution of the electrical signal allow for the quantification of i-RBCs (in the range 10-105 i-RBC µL-1) and the distinction of the infection stage. A preliminary validation study on 75 patients with clinical suspect of malaria shows on-field operability, without false negative and a few false positive results. These findings indicate the potential of TMek as a quantitative, stage-selective, rapid test for malaria.

Histoplasmosis Diagnosed in Europe and Israel: A Case Report and Systematic Review of the Literature from 2005 to 2020.

Human histoplasmosis is a mycosis caused by two distinct varieties of a dimorphic fungus: Histoplasma capsulatum var. capsulatum and H. capsulatum var. duboisii. In Europe, it is usually imported by migrants and travellers, although there have been some autochthonous cases, especially in Italy; however, most European physicians are unfamiliar with its clinical and pathological picture, particularly among immunocompromised patients without HIV infection. This systematic review of all the cases of histoplasmosis reported in Europe and Israel between 2005 and 2020 identified 728 cases diagnosed in 17 European countries and Israel described in 133 articles. The vast majority were imported (mainly from Central and South America), but there were also seven autochthonous cases (six in Europe and one in Israel). The patients were prevalently males (60.4%), and their ages ranged from 2 to 86 years. The time between leaving an endemic region and the diagnosis of histoplasmosis varied from a few weeks to more than 40 years. Progressive disseminated histoplasmosis was the most frequent clinical picture among people living with HIV infection (89.5%) or a different immunocompromising condition (57.1%), but it was also recorded in 6.2% of immunocompetent patients. Twenty-eight cases were caused by Histoplasma duboisii. Immunocompromised patients without HIV infection had the worst outcomes, with a mortality rate of 32%.

Limbic encephalitis in a COVID-19 patient?

We describe the case of a 79-year-old woman infected by SARS-CoV-2 and purely neurological confusional syndrome without clinically relevant respiratory disease and NMR alterations of the limbic system.

Case Report: A Fatal Case of West Nile Virus Meningoencephalomyelitis in a Woman with Systemic Lupus Erythematosus Initially Misdiagnosed as SARS-CoV-2 Infection.

We present a fatal case of West Nile virus meningoencephalomyelitis initially misdiagnosed as COVID-19 in a 63-year-old Egyptian woman with a previous diagnosis of systemic lupus erythematosus. The patient's medical history and immunosuppressive therapy, as well as the COVID-19 pandemic, substantially broadened the differential diagnosis of her encephalitis.

Non-human primate and human malaria: past, present and future.

BACKGROUND: Studies of the malaria parasites infecting various non-human primates (NHPs) have increased our understanding of the origin, biology and pathogenesis of human Plasmodium parasites.This review considers the major discoveries concerning NHP malaria parasites, highlights their relationships with human malaria and considers the impact that this may have on attempts to eradicate the disease. RESULTS: The first description of NHP malaria parasites dates back to the early 20th century. Subsequently, experimental and fortuitous findings indicating that some NHP malaria parasites can be transmitted to humans have raised concerns about the possible impact of a zoonotic malaria reservoir on efforts to control human malaria.Advances in molecular techniques over the last 15 years have contributed greatly to our knowledge of the existence and geographical distribution of numerous Plasmodium species infecting NHPs, and extended our understanding of their close phylogenetic relationships with human malaria parasites. The clinical application of such techniques has also made it possible to document ongoing spillovers of NHP malaria parasites (Plasmodium knowlesi, P. cynomolgi, P. simium, P. brasilianum) in humans living in or near the forests of Asia and South America, thus confirming that zoonotic malaria can undermine efforts to eradicate human malaria. CONCLUSIONS: Increasing molecular research supports the prophetic intuition of the pioneers of modern malariology who saw zoonotic malaria as a potential obstacle to the full success of malaria eradication programmes. It is, therefore, important to continue surveillance and research based on one-health approaches in order to improve our understanding of the complex interactions between NHPs, mosquito vectors and humans during a period of ongoing changes in the climate and the use of land, monitor the evolution of zoonotic malaria, identify the populations most at risk and implement appropriate preventive strategies.

Dynamics of the seroprevalence of SARS-CoV-2 antibodies among healthcare workers at a COVID-19 referral hospital in Milan, Italy.

OBJECTIVES: Healthcare workers (HCWs) are at high risk of developing SARS-CoV-2 infection. The aim of this single-centre prospective study was to evaluate the trend of SARS-CoV-2 seroprevalence in HCWs working at the primary referral centre for infectious diseases and bioemergencies (eg, COVID-19) in Northern Italy and investigate the factors associated with seroconversion. METHODS: Six hundred and seventy-nine HCW volunteers were tested for anti-SARS-CoV-2 antibodies three times between 4 March and 27 May 2020 and completed a questionnaire covering COVID-19 exposure, symptoms and personal protective equipment (PPE) training and confidence at each time. RESULTS: SARS-CoV-2 seroprevalence rose from 3/679 to 26/608 (adjusted prevalence: 0.5%, 95% CI 0.1 to 1.7% and 5.4%, 95% CI 3.6 to 7.9, respectively) between the first two time points and then stabilised, in line with the curve of the COVID-19 epidemic in Milan. From the first time point, 61.6% of the HCWs had received training in the use of PPE and 17 (61.5%) of those who proved to be seropositive reported symptoms compatible with SARS-CoV-2 infection. Contacts with ill relatives or friends and self-reported symptoms were independently associated with an increased likelihood of seroconversion (p<0.0001 for both), whereas there was no significant association with professional exposure. CONCLUSION: The seroprevalence of SARS-CoV-2 among the HCWs at our COVID-19 referral hospital was low at the time of the peak of the epidemic. The seroconversions were mainly attributable to extrahospital contacts, probably because the hospital readily adopted effective infection control measures. The relatively high number of asymptomatic seropositive HCWs highlights the need to promptly identify and isolate potentially infectious HCWs.

Anti-SARS-CoV-2 Immunoglobulin Isotypes, and Neutralization Activity Against Viral Variants, According to BNT162b2-Vaccination and Infection History.

Purpose: To compare SARS-CoV-2 antigen-specific antibody production and plasma neutralizing capacity against B.1 wild-type-like strain, and Gamma/P.1 and Delta/B.1.617.2 variants-of-concern, in subjects with different Covid-19 disease and vaccination histories. Methods: Adult subjects were: 1) Unvaccinated/hospitalized for Covid-19; 2) Covid-19-recovered followed by one BNT162b2 vaccine dose; and 3) Covid-19-naïve/2-dose BNT162b2 vaccinated. Multiplex Luminex® immunoassays measured IgG, IgA, and IgM plasma levels against SARS-CoV-2 receptor-binding domain (RBD), spike-1 (S), and nucleocapsid proteins. Neutralizing activity was determined in Vero E6 cytopathic assays. Results: Maximum anti-RBD IgG levels were similar in Covid-19­recovered individuals 8‒10 days after single-dose vaccination and in Covid-19-naïve subjects 7 days after 2nd vaccine dosing; both groups had ≈2­fold higher anti-RBD IgG levels than Unvaccinated/Covid-19 subjects tracked through 2 weeks post-symptom onset. Anti-S IgG expression patterns were similar to RBD within each group, but with lower signal strengths. Viral antigen-specific IgA and IgM levels were more variable than IgG patterns. Anti-nucleocapsid immunoglobulins were not detected in Covid-19-naïve subjects. Neutralizing activity against the B.1 strain, and Gamma/P.1 and Delta/B.1.617.2 variants, was highest in Covid­19-recovered/single-dose vaccinated subjects; although neutralization against the Delta variant in this group was only 26% compared to B.1 neutralization, absolute anti-Delta titers suggested maintained protection. Neutralizing titers against the Gamma and Delta variants were 33‒77% and 26‒67%, respectively, versus neutralization against the B.1 strain (100%) in the three groups. Conclusion: These findings support SARS-CoV-2 mRNA vaccine usefulness regardless of Covid-19 history, and confirm remarkable protection provided by a single vaccine dose in people who have recovered from Covid-19.

Characterization of the cytokine storm reflects hyperinflammatory endothelial dysfunction in COVID-19.

BACKGROUND: Physicians treating patients with coronavirus disease 2019 (COVID-19) increasingly believe that the hyperinflammatory acute stage of COVID-19 results in a cytokine storm. The circulating biomarkers seen across the spectrum of COVID-19 have not been characterized compared with healthy controls, but such analyses are likely to yield insights into the pursuit of interventions that adequately reduce the burden of these cytokine storms. OBJECTIVE: To identify and characterize the host inflammatory response to severe acute respiratory syndrome coronavirus 2 infection, we assessed levels of proteins related to immune responses and cardiovascular disease in patients stratified as mild, moderate, and severe versus matched healthy controls. METHODS: Blood samples from adult patients hospitalized with COVID-19 were analyzed using high-throughput and ultrasensitive proteomic platforms and compared with age- and sex-matched healthy controls to provide insights into differential regulation of 185 markers. RESULTS: Results indicate a dominant hyperinflammatory milieu in the circulation and vascular endothelial damage markers within patients with COVID-19, and strong biomarker association with patient response as measured by Ordinal Scale. As patients progress, we observe statistically significant dysregulation of IFN-γ, IL-1RA, IL-6, IL-10, IL-19, monocyte chemoattractant protein (MCP)-1, MCP-2, MCP-3, CXCL9, CXCL10, CXCL5, ENRAGE, and poly (ADP-ribose) polymerase 1. Furthermore, in a limited series of patients who were sampled frequently, confirming reliability and reproducibility of our assays, we demonstrate that intervention with baricitinib attenuates these circulating biomarkers associated with the cytokine storm. CONCLUSIONS: These wide-ranging circulating biomarkers show an association with increased disease severity and may help stratify patients and selection of therapeutic options. They also provide insights into mechanisms of severe acute respiratory syndrome coronavirus 2 pathogenesis and the host response.

Bacteriophage therapy: an overview and the position of Italian Society of Infectious and Tropical Diseases.

In recent years, the increase of antibiotic resistance and the lack in the pipeline of novel antimicrobial molecules make bacterial infections difficult to treat. Among European countries, Italy is the one region with a higher number of deaths caused by antibiotic-resistant bacteria. Moreover, a major concern is represented by biofilm-related infections. The ability of bacteria to form biofilm in presence of implanted-medical devices represents a further challenge for the treatment of bacterial infections. Thus, the development of alternative strategies to fight multi-drug resistant bacteria embedded in biofilms is an urgent need. Nowadays, bacteriophage therapy represents one of the potential and promising treatment options to overcome antibiotic resistance phenomenon. Bacteriophages are viruses capable to infect and replicate within bacterial cell. They are widespread in soil and water and play a role in microbial physiology. Since their discovery at the beginning of the twentieth century bacteriophages were used with therapeutic purposes against bacterial infections. However, the advent of the antibiotic era spurred medical doctors to abandon phage therapy in return for the most promising antibiotic therapy. For historical reasons, only few countries in the world, including Georgia, Russia and Poland have carried on the use of phages for therapeutic purposes and have developed specialised research and treatment centres, where phage therapy is permitted and applied to cure infectious disease. Although the efficacy of bacteriophages for treatment of infections is widely documented, the introduction of phage therapy in common management of bacterial infections in European hospital is hindered by the lack of an appropriate legal and regulatory framework. Different strategies have been used to overcome this problem, like the "Magistral Phage" preparation in Belgium. Here, we provide a review of the fundamental concept on bacteriophage therapy and propose this treatment as a possible alternative choice when antibiotics and surgery are not enough to eradicate a bacterial infection. We believe that the introduction of phage therapy in Italy might improve the quality of life of patients suffering of chronic bacterial infections and fight antibiotic resistances problem. To reach this goal the support and the promotion of Italian government and the scientific authorities is essential. SIMIT, the Italian Society of Infectious and Tropical Diseases, proposes to support the creation of an Italian Task Force to improve knowledge on bacteriophage therapy, collect stronger evidence about their efficacy and develop appropriate protocols for phage administration.