Maria Beatrice Valli

Dr. Maria Beatrice Valli

orcid

Research Focus & Metrics

Academic Career Length

16Years (2011-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
23 May 2011 in BMC Infectious Diseases
Verified
Journal Article
Open access
PDF file
SMSilvia Meschi
Silvia Meschi
MSMarina Selleri
Marina Selleri
ELEleonora Lalle
Eleonora Lalle
LBLicia Bordi
Licia Bordi
MVMaria Beatrice Valli
Maria Beatrice Valli
MCMaria Capobianchi
Maria Capobianchi
Background: The first influenza pandemic of the 21th century was ignited by a new strain of influenza A virus (A/H1N1pdm). Specific patient groups, including those with comorbidities, pregnant women, young children, older and immunocompromised patients, are at increased risk for serious influenza-related disease. This study was aimed at investigating the influence of clinical presentation, antiviral treatment and possible drug resistance-associated mutations, on the extent and duration of viral shedding in patients infected with A/H1N1pdm. Methods: An observational study was performed, based on retrospective review of clinical and laboratory records of patients who were hospitalized for A/H1N1pdm infection at the National Institute for Infectious Diseases "L. Spallanzani", Rome, Italy, between April 24 and December 31, 2009. Among 119 hospitalized patients, 39 were selected for a post hoc analysis, based on the availability of serial nasopharyngeal swabs samples and related information. Results: Eleven out of the 39 study patients (28.2%) presented with pneumonia; 29 (74.4%) received antiviral treatment. Patients with pneumonia were significantly older than patients without pneumonia. The mean values of viral RNA concentration were not significantly increased in patients with pneumonia, but a significant increase in the duration of viral shedding was observed as compared to patients without pneumonia. In patients receiving antivirals, the viral RNA concentration was significantly reduced in comparison to untreated patients at days 4-5 after symptom onset, while the overall duration of viral shedding was only marginally affected. A significant correlation between duration of viral shedding and time elapsed between symptom onset and therapy start was observed, with a significant reduction of days of viral shedding when therapy was initiated within 2 days of symptoms appearance. No known drug resistance mutations were detected in patients with prolonged viral shedding. Conclusions: Our results show that severe respiratory illness is associated with delayed virus clearance in patients with A/H1N1pdm infection. Antivirals caused an early reduction of viral load, but only marginally affected the overall duration of shedding. Prolonged shedding was not associated with the emergence of strains carrying known drug-resistance mutations.

1 October 2017 in Emerging Infectious Diseases
Verified
Journal Article
Open access
EGEmanuela Giombini
Emanuela Giombini
MRMartina Rueca
Martina Rueca
WBWalter Barberi
Walter Barberi
AIAnna Paola Iori
Anna Paola Iori
Concetta CastillettiConcetta Castilletti
Concetta Castilletti
MVMaria Beatrice Valli
Maria Beatrice Valli
In Italy in 2016, acute flaccid myelitis developed in a woman who had received a hematopoietic stem cell transplant. Enterovirus D68 viral genome was detected in respiratory and cerebrospinal fluid samples, and the viral protein 1 sequence clustered with lineage B3. Immunocompromised adults may be at risk for enterovirus D68–associated neurologic complications.

13 March 2021 in Biomolecules
Verified
Journal Article
Open access
PDF file
FCFrancesca Colavita
Francesca Colavita
FVFrancesco Vairo
Francesco Vairo
SMSilvia Meschi
Silvia Meschi
MVMaria Beatrice Valli
Maria Beatrice Valli
ELEleonora Lalle
Eleonora Lalle
MCMaria Capobianchi
Maria Capobianchi
COVID-19 pandemic is a dramatic health, social and economic global challenge. There is urgent need to maximize testing capacity. Rapid Antigen Tests (RAT) represent good candidates for point-of-care and mass surveillance testing to rapidly identify SARS-CoV-2-infected people, counterbalancing lower sensitivity vs. gold standard molecular tests with fast results and possible recurrent testing. We describe the results obtained with the testing algorithm implemented at points of entry (airports and ports) in the Lazio Region (Italy), using the STANDARD F COVID-19 Antigen Fluorescence ImmunoAssay (FIA), followed by molecular confirmation of FIA-positive samples. From mid-August to mid-October 2020, 73,643 RAT were reported to the Regional Surveillance Information System for travelers at points of entry in Lazio Region. Of these, 1176 (1.6%) were FIA-positive, and the proportion of RT-PCR-confirmed samples was 40.5%. Our data show that the probability of confirmation was directly dependent from the semi-quantitative FIA results. In addition, the molecularly confirmed samples were those with high levels of virus and that were actually harboring infectious virus. These results support public health strategies based on early mass screening campaigns by RAT in settings where molecular testing is not feasible or easily accessible, such as points of entry. This approach would contribute to promptly controlling viral spread through travel, which is now of particular concern due to the spread of SARS-CoV-2 variants.

30 April 2021 in Journal of Endocrinological Investigation
Verified
Journal Article
Open access
PDF file
Donatella PaoliDonatella Paoli
Donatella Paoli
FPFrancesco Pallotti
Francesco Pallotti
GNGerardo Nigro
Gerardo Nigro
LML. Mazzuti
L. Mazzuti
MHM. N. Hirsch
M. N. Hirsch
FLFrancesco Lombardo
Francesco Lombardo
Purpose: Due to relevant repercussions on reproductive medicine, we aimed to evaluate feasibility of RT-PCR as a detection method of SARS-CoV-2 RNA in seminal fluid. Methods: A qualitative determination of the RT-PCR assays in semen was performed through different approaches: (1) efficiency of RNA extraction from sperm and seminal plasma was determined using PRM1 and PRM2 mRNA and a heterologous system as control; (2) samples obtained by diluting viral preparation from a SARS-CoV-2 panel (virus cultured in Vero E6 cell lines) were tested; (3) viral presence in different fractions of seminal fluid (whole sample, seminal plasma and post-centrifugation pellet) was evaluated. Semen samples from mild and recovered COVID-19 subjects were collected by patients referring to the Infectious Disease Department of the Policlinico Umberto I Hospital - “Sapienza” University of Rome. Control subjects were recruited at the Laboratory of Seminology-Sperm Bank “Loredana Gandini'' of the same hospital. Results: The control panel using viral preparations diluted in saline and seminal fluid showed the capability to detect viral RNA presence with Ct values depending on the initial viral concentration. All tested semen samples were negative for SARS-CoV-2, regardless of the nasopharyngeal swab result or seminal fluid fraction. Conclusion: These preliminary data show that RT-PCR for SARS-CoV-2 RNA testing appears to be a feasible method for the molecular diagnosis of SARS-CoV-2 in seminal fluid, supported by results of the control panel. The ability to detect SARS-CoV-2 in semen is extremely important for reproductive medicine, especially in assisted reproductive technology and sperm cryopreservation.

GSGiuseppe Sberna
Giuseppe Sberna
ELEleonora Lalle
Eleonora Lalle
MVMaria Beatrice Valli
Maria Beatrice Valli
LBLicia Bordi
Licia Bordi
Anna Rosa GarbugliaAnna Rosa Garbuglia
Anna Rosa Garbuglia
AAAlessandra Amendola
Alessandra Amendola
A descriptive analysis of common respiratory pathogens (CRPs) detected in nasopharyngeal swabs (NPSs) from hospitalized patients with influenza-like illness during the fall seasons of the past three years, 2019–2021, in the Lazio region, Italy, was conducted to assess whether or not CRP circulation changed because of COVID-19 during the fall season. The results observed in a total of 633 NPSs subjected to molecular diagnosis for CRPs by multiplex PCR assay during the autumn seasons (exactly from week 41 to week 50) were compared with each other. In 2019, in 144 NPSs, the more represented CRPs were rhinovirus/enterovirus (7.6%) and influenza A/B (4.2%). In 2020, 55 (21.6%) out of 255 NPSs resulted positive for SARS-CoV-2 and, except for one case of Legionella pneumophila, the CRPs detected were exclusively rhinovirus/enterovirus (4.7%). In 2021, among 234 NPSs, 25.6% resulted positive for SARS-CoV-2, 14.5% for respiratory syncytial virus (RSV), and 12.8% for rhinovirus/enterovirus. Compared with 2019, in 2020, CRP circulation was severely limited to a few cases; in 2021, instead, infections by RSV (detected also among adults), rhinovirus/enterovirus, and other respiratory pathogens were observed again, while influenza was practically absent. The comparison of the CRPs detected in the NPSs depicts a different circulation in the Lazio region during the last three fall seasons. CRP monitoring has a direct impact on the prevention and control strategies of respiratory infectious diseases, such as the non-pharmacological interventions implemented in response to the COVID-19 pandemic. Future studies should investigate the impact of specific interventions on the spread of respiratory infections.

1 January 2016 in Clinical Microbiology and Infectious Diseases
Verified
Journal Article
Open access
FCFrancesca Colavita
Francesca Colavita
CVCarolina Venditti
Carolina Venditti
AVAntonella Vulcano
Antonella Vulcano
Concetta CastillettiConcetta Castilletti
Concetta Castilletti
PZPaola Zaccaro
Paola Zaccaro
ACAntonino Di Caro
Antonino Di Caro