Breakthrough Infections of E484K-Harboring SARS-CoV-2 Delta Variant, Lombardy, Italy.

The Delta variant of concern of severe acute respiratory syndrome coronavirus 2 is dominant worldwide. We report a case cluster caused by Delta sublineage B.1.617.2 harboring the mutation E484K in Italy during July 11-July 29, 2021. This mutation appears to affect immune response and vaccine efficacy; monitoring its appearance is urgent.

Symptomatic SARS-CoV-2 infections after full schedule BNT162b2 vaccination in seropositive healthcare workers: a case series from a single institution.

We report 11 cases of SARS-CoV-2 infection in healthcare workers (HCW) naïve for COVID-19 and seropositive after the second dose of the BNT162b2 mRNA vaccine. Based on voluntary-based surveillance, they tested positive for different strains of SARS-CoV-2, as Spike gene sequencing showed. Five of them reported mild symptoms. Given the risk for SARS-CoV-2 introduction from asymptomatic vaccinees, this case series suggests the need to continue nasopharyngeal screening programmes.

HHV8 a subtype is associated with rapidly evolving classic Kaposi's sarcoma.

The link between human herpesvirus 8 (KSHV) and Kaposi's sarcoma (KS) has been proven, but many important aspects including risk factors, genetic predisposition to tumor development, transmission of KSHV, and the pathogenic potential of different genotypes remain to be elucidated. Possible associations between clinical parameters and antibody levels, viral load fluctuations, and viral genotype were analyzed by quantitative real-time PCR, an in-house developed IFA assay, and sequence analysis of ORF K1-VR1 in blood, serum and saliva of 38 subjects with classic KS (cKS). KSHV lytic antibodies were significantly increased in stage IV compared to stage I and II patients (p = 0.006 and p = 0.041, respectively). KSHV blood, serum, and saliva viral load was comparable in all stages. The highest viral loads were detected in saliva, and they decreased in stages III-IV compared to stages I-II patients. Higher concentrations of lytic antibodies and higher viral loads were observed in fast progressing cKS patients, in whom KSHV detection from blood was also more frequent. Type A KSHV strain was almost exclusively present in rapid progressors (12/17 cases), while C type was mainly present in slow progressing patients (6/7 cases). Finally, detection of type A KSHV strain associated with higher blood viral loads. KSHV lytic antibody levels and viral load can be used to monitor clinical evolution of cKS. Infection supported by KSHV A subtype is associated with more rapid progressive disease. Careful monitoring and aggressive therapeutic protocols should be considered in patients with KSHV A-supported infection.

Presence, quantitation and characterization of JC virus in the urine of Italian immunocompetent subjects.

Human polyomavirus JC (JCV) infects the worldwide population, remains latent in the kidney, and is excreted in the urine. A longitudinal study was performed in order to evaluate JCV excretion, to characterize molecularly the virus and to determine if its presence in urine is a consequence of viral reactivation or merely of epithelial squamous cell shedding. The presence of cellular sediment and the JCV genome were examined in 333 urine samples collected periodically for 3 months from 17 healthy subjects; molecular characterization, and quantitation of the virus were also undertaken. JCV DNA was detected in 40.2% of the samples, with a significant difference (P<0.001) observed between males and females. JCV shedding was independent of the presence of cellular sediment in every individual. JCV genotype 1 was the genome detected most frequently, while all of the amplified strains showed archetypal organization of the transcriptional control region (TCR). No clinical symptoms have been associated with JCV excretion and no microbial load was detected in the urine samples. The lack of correlation between JCV DNA detection and the presence of squamous cells in urine sediment indicates that viruria is regulated by the life cycle of JCV. Thus, the virus is eliminated as consequence of its reactivation.

A case of a progressive multifocal leukoencephalopathy patient with four different JC virus transcriptional control region rearrangements in cerebrospinal fluid, blood, serum, and urine.

JC virus (JCV) is the etiological agent of progressive multifocal leukoencephalopathy (PML), a fatal demyelinating disease of the central nervous system (CNS). During the acquired immunodeficiency syndrome (AIDS) epidemic, it was the cause of the death in up to 8% of AIDS patients. The genomic organization of JCV and, in particular, the hypervariability of the transcriptional control region (TCR), a regulatory noncoding region, are well known. Given that the TCR plays a central role in the viral replication of JCV, a crucial role in the determination of the neurotropism and in the pathogenic capabilities of the virus is also suspected. Here the authors describe a case of PML that did not respond to highly active antiretroviral therapy (HAART) therapy. There was a simultaneous presence of JCV strains with four different TCR structures in urine, peripheral blood cells, serum, and cerebrospinal fluid (CSF) samples. These data confirmed that the presence of the archetype TCt is restricted to urine, while also suggesting that the degree of the rearrangement varies and increases from the peripheral blood to CSF.

Detection of herpesvirus-6A in a case of subacute cerebellitis and myoclonic dystonia.

This is a case study of a child who developed roseola infantum first, then varicella, and was later affected by acute cerebellar syndrome, severe truncal ataxia, and myoclonic dystonia. Human herpesvirus 6 (HHV-6) A and B were detected in the cerebrospinal fluid (CSF) and peripheral blood, respectively, upon ataxia onset. The intricacy of this case suggests multifaceted conclusions ranging from the need for a multidirectional approach to neurological diseases, to confirmation of a more pronounced neurotropism of HHV-6A and a possible role of viruses in myoclonic dystonia syndrome, although this last hypothesis should be confirmed by larger studies.

Bactericidal activity of levofloxacin, gatifloxacin, penicillin, meropenem and rokitamycin against Bacillus anthracis clinical isolates.

This study aimed to evaluate the bactericidal rates of levofloxacin, gatifloxacin, penicillin, meropenem and rokitamycin against seven isolates of Bacillus anthracis clinically isolated between 1960 and 1970. After determination of MIC and MBC, time-kill experiments were carried out. Antimicrobial activity was evaluated at concentrations equal to 1 x, 2 x, 4 x and 8 x MIC after 0, 3, 6, 12 and 24 h of incubation with the drugs. Bactericidal activity was defined as a decrease in bacterial count of at least 3 log10. All the isolates were susceptible to all the antibiotics, by considering the antistaphylococcal breakpoints. Levofloxacin was bactericidal at 1 x MIC after 24 h and at 4 x MIC after 12 h, and gatifloxacin was bactericidal at 2 x MIC after 24 h and at 8 x MIC after 12 h. Meropenem, rokitamycin and penicillin also showed bactericidal activity at concentrations of 4 x and 8 x MIC, respectively, but only after 24 h incubation; after the same time, meropenem and rokitamycin showed a more marked killing than penicillin at 2 x MIC.