SARS-CoV-2 vaccine development: where are we?

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has proved to be one of the most challenging infectious diseases in the modern era, and despite several countermeasures to lessen its impact, the spread of the virus is still affecting most countries. This renders the goal of active immunization of the population through vaccination a worldwide public health priority. In fact, only when efficient vaccination programs will be successfully implemented, a return to pre-pandemic normality can be considered. The scientific community has made a tremendous effort to blow the lid off the pathogenesis of the disease, and unprecedented efforts are ongoing with governments, private organizations, and academics working together to expeditiously develop safe and efficacious vaccines. Previous research efforts in the development of vaccines for other coronaviruses (Severe Acute Respiratory Syndrome Coronavirus 1 and Middle East Respiratory Syndrome Coronavirus) as well other emerging viruses have opened the door for exploiting several strategies to design a new vaccine against the pandemic virus. Indeed, in a few months, a stunning number of vaccines have been proposed, and almost 50 putative vaccine candidates have entered clinical trials. The different vaccine candidates use different vaccine development platforms, from inactivated whole virus vaccine to subunit vaccine, nucleic acid, and vectored vaccines. In this review, we describe strengths, flaws, and potential pitfalls of each approach to understand their chances of success.

Methicillin-resistant Staphylococcus aureus: epidemiology and antimicrobial susceptibility experiences from the University Hospital 'Luigi Vanvitelli' of Naples.

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the important pathogens worldwide showing resistance to several widely used antibiotics. This has made the treatment of MRSA infections harder, especially due to their prevalence in the hospital setting. We evaluated the antibiotic susceptibility patterns of healthcare-associated MRSA infections with a focus on Vancomycin Intermediate S. Aureus (VISA) and macrolide-licosamide-streptogramin B (MLSB) phenotypes. A total of 417 Staphylococcus aureus (S. aureus) cases were isolated between January 2017 and December 2018, through several clinical specimens collected from the University Hospital 'Luigi Vanvitelli' of Naples. We identified bacterial strains using Matrix-Assisted Laser Desorption/Ionization-Time of Flight (MALDI-TOF) and antimicrobial susceptibility using Phoenix BD (Becton Dickinson, NJ, USA). Out of the total 417 S. aureus cases, 140 were MRSA (33.6%) and of these, 50% were soft tissue infections. All MRSA and Methicillin sensible S.aureus MSSA isolates were susceptible to linezolid and daptomycin. Two MRSA cases exhibited intermediate resistance to vancomycin and were of constitutive MLSB phenotype. Among the MRSA strains, 11.4% were constitutive and 43.6% were inducible MLSB phenotypes and 8.6% were macrolide-streptogramin B phenotype. This study characterized the epidemiological status, antibiotic resistance patterns, and current prevalent phenotypes of healthcare-associated MRSA. This knowledge can aid clinicians in improving the antimicrobial stewardship program by adapting appropriate guidelines for the proper use of MRSA antibacterial agents.