The role of vaccination route with an adenovirus-vectored vaccine in protection, viral control, and transmission in the SARS-CoV-2/K18-hACE2 mouse infection model.

Introduction: Vaccination is the most effective mechanism to prevent severe COVID-19. However, breakthrough infections and subsequent transmission of SARS-CoV-2 remain a significant problem. Intranasal vaccination has the potential to be more effective in preventing disease and limiting transmission between individuals as it induces potent responses at mucosal sites. Methods: Utilizing a replication-deficient adenovirus serotype 5-vectored vaccine expressing the SARS-CoV-2 RBD (AdCOVID) in homozygous and heterozygous transgenic K18-hACE2, we investigated the impact of the route of administration on vaccine immunogenicity, SARS-CoV-2 transmission, and survival. Results: Mice vaccinated with AdCOVID via the intramuscular or intranasal route and subsequently challenged with SARS-CoV-2 showed that animals vaccinated intranasally had improved cellular and mucosal antibody responses. Additionally, intranasally vaccinated animals had significantly better viremic control, and protection from lethal infection compared to intramuscularly vaccinated animals. Notably, in a novel transmission model, intranasal vaccination reduced viral transmission to naïve co-housed mice compared to intramuscular vaccination. Discussion: Our data provide convincing evidence for the use of intranasal vaccination in protecting against SARS-CoV-2 infection and transmission.

Antibiotic prophylaxis in foot and ankle surgery: a systematic review of the literature.

BACKGROUND: With the advent of bacterial resistance, it is important now more than ever to evaluate use of antibiotic chemoprophylaxis in foot and ankle surgery. Within this area of the body there may be less dissection, surgery time with smaller incisions and importantly smaller sizes of implanted fixation as compared to other bone and joint procedures. Our objective was to systematically evaluate the quality of evidence behind existing guidelines. METHODOLOGY: A systematic literature search was performed: MEDLINE, CINHAL, EMBASE and the Cochrane library from 1990 up to March 2018. To avoid omitting any studies on the subject, Google Scholar was also used. The inclusion criterion were studies exploring perioperative antibiotic use, postoperative infection rates in elective foot and ankle surgery and studies associated with this subject evaluating antibiotic use in clean elective foot and ankle surgery. The exclusion criterion being studies upon contaminated or dirty surgery or those which were inclusive of procedures proximal to the foot and ankle. RESULTS: Overall 11 studies met the inclusion criteria. From the grading of evidence, 2 level one and 4 level two studies were recognised. These studies ranked relatively highly in comparison to 5 studies that were graded as level three and level four tiers of evidence. Results of SSI rates found within this systematic review ranged from 0% to 9.4% of overall postoperative infections encountered after foot and ankle surgery in the studies analysed. CONCLUSION: Whilst fragmented, aspects of antibiotic chemoprophylaxis are established fields in elective surgery with a growing body of evidence. Evidence for antibiotic use however, specifically within elective foot and ankle surgery, is lacking. This systematic review is a seminal paper which delivers an impression of the most influential literature within the field of foot and ankle surgery, with the aim being to entice conclusions and guide future research.