Geographical reconstruction of the SARS-CoV-2 outbreak in Lombardy (Italy) during the early phase.

The first identification of autochthonous transmission of SARS-CoV-2 in Italy was documented by the Laboratory of Clinical Microbiology, Virology and Bioemergencies of L. Sacco Hospital (Milano, Italy) on 20th February 2020 in a 38 years old male patient, who was found positive for pneumonia at the Codogno Hospital. Thereafter Lombardy has reported the highest prevalence of COVID-19 cases in the country, especially in Milano, Brescia and Bergamo provinces. The aim of this study was to assess the potential presence of different viral clusters belonging to the six main provinces involved in Lombardy COVID-19 cases in order to highlight peculiar province-dependent viral characteristics. A phylogenetic analysis was conducted on 20 full length genomes obtained from patients addressing to several Lombard hospitals from February 20th to April 4th, 2020, aligned with 41 Italian viral genome assemblies available on GISAID database as of 30th March, 2020: two main monophyletic clades, containing 8 and 53 isolates, respectively, were identified. Noteworthy, Bergamo isolates mapped inside the small clade harbouring M gene D3G mutation. The molecular clock analysis estimated a cluster divergence approximately one month before the first patient identification, supporting the hypothesis that different SARS-CoV-2 strains had spread worldwide at different times, but their presence became evident only in late February along with Italian epidemic emergence. Therefore, this epidemiological reconstruction suggests that virus initial circulation in Lombardy was ascribable to multiple introduction. The phylogenetic reconstruction robustness, however, will be improved when more genomic sequences are available, in order to guarantee a complete epidemiological surveillance.

Occurrence of Lyme disease infection in a non-endemic area in Northern Italy.

BACKGROUND: In Italy, the incidence of human tick-borne disease has increased over the last decades. Since 2015 a multidisciplinary group has been established in Sacco Hospital for the management of the patients affected by Lyme disease (LD). A retrospective evaluation (2015-2017) was performed for LD in non-endemic areas. METHODS: Retrospective analysis of all 1000 samples for 800 patients screened for LD antibodies at the Sacco Hospital in 3 years (2015-2017). Clinical and epidemiological data were collected and compared with the serological results. RESULTS: Among the 800 patients screened, 134 of them were diagnosed with borreliosis during 2015 (37 cases), 2016 (31 cases) and 2017 (66 cases). Localized LD was diagnosed 100 out of 134 cases (69%): in most of them (N.=63) erythema migrans has been documented; in 37 out of 100 it was not possible to detect it. In only three cases, patients complained of different clinical symptoms such as headache, arm and facial pain respectively. 23 out of 134 cases (16%) showed a persistence of serological positivity and symptoms with osteomuscular involvement and fatigue, despite the therapy (late LD). In that same study 11 out of 134 patients (7%) received a diagnosis of neuroborreliosis. CONCLUSIONS: Our data reported a high percentage of LD infection (19%) in a non-endemic area. The definition of a Multidisciplinary Working Group and a clinical care pathway allowed a better clinical management of LD cases treated in Sacco Hospital, Milan.

Impact of NRTI resistance mutations on virological effectiveness of antiretroviral regimens containing elvitegravir: a multi-cohort study.

BACKGROUND: Antiretroviral drug resistance mutations remain a major cause of treatment failure. OBJECTIVES: To evaluate the impact of NRTI resistance mutations on virological effectiveness of elvitegravir-containing regimens. MATERIALS AND METHODS: We selected treatment-experienced HIV-1-infected patients starting elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide (E/C/F/TAF) or elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil fumarate (E/C/F/TDF), with at least one protease/reverse transcriptase genotype available before switching and at least one HIV-1 RNA viral load (VL) measurement during follow-up. The primary endpoint was virological failure (VF), defined as one VL value of ≥1000 copies/mL or two consecutive VL values of >50 copies/mL. RESULTS: We included 264 ART regimens: 75.6% male, median (IQR) age 47 years (39-53), 7 years (3-16) of HIV infection, nadir CD4+ 247 cells/mm3 (105-361), 81.5% with VL ≤50 copies/mL and 11.7% with at least one NRTI mutation at baseline. Eleven (5.2%) VFs occurred in virologically suppressed patients versus eight (15.1%) in viraemic patients. The estimated probability of VF at 48 weeks with versus without any NRTI mutation was 7.4% (95% CI 2.3-12.5) versus 3.8% (2.1-5.5) in virologically suppressed patients and 66.7% (39.5-93.9) versus 11.2% (6.5-15.9) (P<0.001) in viraemic patients. The only predictor of VF was time on therapy (per 1 year more, adjusted HR 1.14, 95% CI 1.02-1.27, P=0.024) in viraemic patients. CONCLUSIONS: A switch to E/C/F/TDF or E/C/F/TAF is safe for virologically suppressed patients without documented NRTI resistance, but not recommended in viraemic patients with a history of NRTI resistance. Although we did not detect a detrimental effect of past NRTI resistance in virologically suppressed patients, a fully active regimen remains preferred in this setting due to possible rebound of drug-resistant virus in the long term.

Lyme borreliosis incidence in Lombardy, Italy (2000-2015): Spatiotemporal analysis and environmental risk factors.

Lyme borreliosis cases have been reported from Lombardy in northern Italy, where Ixodes ricinus is the main vector of Borrelia burgdorferi sensu lato. However, spatial and temporal variation in the incidence of Lyme borreliosis is not well understood. In the present study, based on new notified cases of Lyme borreliosis from 2000 to 2015, an average of 1.24 new cases per million residents per year was documented. New cases, georeferenced at the municipal level, were analyzed by retrospective space-time analysis (using SaTScan v. 9.3.1); and land cover, extrapolated from a Corine Land Cover dataset (using QGIS 2.8.1), was used to implement an environmental risk factor analysis. Firstly, a temporal high-risk cluster was detected in Lombardy: the relative risk of Lyme borreliosis was 3.73 times higher during 2008-2015 compared with the entire study period. Moreover, in a spatiotemporal high-risk cluster with a circular base, land cover consisting of wildland-urban interface, meadow, forest and meadow-forest transition were significantly higher compared to low-risk areas. Results of the present study demonstrate that the incidence of Lyme borreliosis is increasing in Lombardy and that environmental conditions are suitable for I. ricinus ticks infected with B. burgdorferi s.l.: citizens and health systems should be aware of Lyme borreliosis to reduce tick bites with personal protective behaviors and to avoid misdiagnosis, particularly within the area including the observed high-risk cluster. Economic resources should be invested to inform about methods to prevent tick bites, how to check people and pets after frequenting risk areas, and ways of removing the biting ticks when they are found.

Remitting infections due to community-acquired Panton-Valentine leukocidin-producing Staphylococcus aureus in the Milan area.

One of the most important Staphylococcus aureus virulence factors is Panton-Valentine leukocidin (PVL). We describe an outbreak of recurrent cutaneous PVL infections in different members of three family clusters. Molecular investigations were performed to confirm the presence of the mecA and PVL genes and to assign the SCCmec type, sequence type (ST) and clonal relatedness. A strain of PVL-producing methicillin-resistant S. aureus (MRSA) was responsible for infection in two related families (A and B), and a third family (C) was infected with PVL-producing methicillin-sensitive S. aureus (MSSA). Molecular investigations revealed the same clone of community-acquired (CA)-MRSA, PVL positive ST8, and SCCmec IV in families A and B and CA-MSSA PVL positive ST15 in family C. S. aureus PVL may give rise to recurrent uncontrolled infections that are difficult to eradicate, and close family contacts are at high risk for transmission.

Use of Dithiothreitol to Dislodge Bacteria From the Biofilm on an Aortic Valve in the Operating Theatre: A Case of Infective Endocarditis Caused by Staphylococcus aureus and Proteus mirabilis.

This is the first reported case of 2 biofilm-producing bacteria, Staphylococcus aureus and Proteus mirabilis, identified from an aortic valve using an innovative device with dithiothreitol solution, able to dislodge bacterial biofilm. The method is usable in the operating theatre and recommended in infective endocarditis nonresponders to empiric therapy.

Diffusion and transmission of carbapenem-resistant Klebsiella pneumoniae in the medical and surgical wards of a university hospital in Milan, Italy.

Carbapenem-resistant Klebsiella pneumoniae (CRKP) is emerging as a public health problem worldwide. In Italy, a remarkable increase in CRKP cases has been reported since 2010. In this study, CRKP diffusion, distribution and in-hospital transmission trends were evaluated in a university hospital in Milan, Italy, from January 2012 to December 2013. Isolates from 63 newly detected CRKP-positive patients were genotyped, and possible transmission was determined by combining the molecular results with data concerning the patients' admission and in-hospital transfers. Most of the cases (90.4%) were from general medical and surgery wards, and the remaining 9.6% were from the intensive care unit. Fifteen of the 46 hospital-associated cases (32.6%) were attributable to in-hospital transmission. After the introduction of targeted and hospital-wide control measures, the transmission index significantly decreased from 0.65 to 0.13 (p=0.01). There was also a decrease in the overall nosocomial case incidence, from 0.37 to 0.17 per 1000 person-days (p=0.07). Our findings indicate that the spread of CRKP in Northern Italy hospitals may go far beyond high-risk settings (i.e., intensive care units) and that strict surveillance should be extended to general areas of care.

Salinomycin and other ionophores as a new class of antimalarial drugs with transmission-blocking activity.

The drug target profile proposed by the Medicines for Malaria Venture for a malaria elimination/eradication policy focuses on molecules active on both asexual and sexual stages of Plasmodium, thus with both curative and transmission-blocking activities. The aim of the present work was to investigate whether the class of monovalent ionophores, which includes drugs used in veterinary medicine and that were recently proposed as human anticancer agents, meets these requirements. The activity of salinomycin, monensin, and nigericin on Plasmodium falciparum asexual and sexual erythrocytic stages and on the development of the Plasmodium berghei and P. falciparum mosquito stages is reported here. Gametocytogenesis of the P. falciparum strain 3D7 was induced in vitro, and gametocytes at stage II and III or stage IV and V of development were treated for different lengths of time with the ionophores and their viability measured with the parasite lactate dehydrogenase (pLDH) assay. The monovalent ionophores efficiently killed both asexual parasites and gametocytes with a nanomolar 50% inhibitory concentration (IC50). Salinomycin showed a fast speed of kill compared to that of standard drugs, and the potency was higher on stage IV and V than on stage II and III gametocytes. The ionophores inhibited ookinete development and subsequent oocyst formation in the mosquito midgut, confirming their transmission-blocking activity. Potential toxicity due to hemolysis was excluded, since only infected and not normal erythrocytes were damaged by ionophores. Our data strongly support the downstream exploration of monovalent ionophores for repositioning as new antimalarial and transmission-blocking leads.