How effective is the BNT162b2 mRNA vaccine against SARS-CoV-2 transmission and infection? A national programme analysis in Monaco, July 2021 to September 2022.

BACKGROUND: We quantified SARS-CoV-2 dynamics in different community settings and the direct and indirect effect of the BNT162b2 mRNA vaccine in Monaco for different variants of concern (VOC). METHODS: Between July 2021 and September 2022, we prospectively investigated 20,443 contacts from 6320 index cases using data from the Monaco COVID-19 Public Health Programme. We calculated secondary attack rates (SARs) in households (n = 13,877), schools (n = 2508) and occupational (n = 6499) settings. We used binomial regression with a complementary log-log link function to measure adjusted hazard ratios (aHR) and vaccine effectiveness (aVE) for index cases to infect contacts and contacts to be infected in households. RESULTS: In households, the SAR was 55% (95% CI 54-57) and 50% (48-51) among unvaccinated and vaccinated contacts, respectively. The SAR was 32% (28-36) and 12% (10-13) in workplaces, and 7% (6-9) and 6% (3-10) in schools, among unvaccinated and vaccinated contacts respectively. In household, the aHR was lower in contacts than in index cases (aHR 0.68 [0.55-0.83] and 0.93 [0.74-1.1] for delta; aHR 0.73 [0.66-0.81] and 0.89 [0.80-0.99] for omicron BA.1&2, respectively). Vaccination had no significant effect on either direct or indirect aVE for omicron BA.4&5. The direct aVE in contacts was 32% (17, 45) and 27% (19, 34), and for index cases the indirect aVE was 7% (- 17, 26) and 11% (1, 20) for delta and omicron BA.1&2, respectively. The greatest aVE was in contacts with a previous SARS-CoV-2 infection and a single vaccine dose during the omicron BA.1&2 period (45% [27, 59]), while the lowest were found in contacts with either three vaccine doses (aVE - 24% [- 63, 6]) or one single dose and a previous SARS-CoV-2 infection (aVE - 36% [- 198, 38]) during the omicron BA.4&5 period. CONCLUSIONS: Protection conferred by the BNT162b2 mRNA vaccine against transmission and infection was low for delta and omicron BA.1&2, regardless of the number of vaccine doses and previous SARS-CoV-2 infection. There was no significant vaccine effect for omicron BA.4&5. Health authorities carrying out vaccination campaigns should bear in mind that the current generation of COVID-19 vaccines may not represent an effective tool in protecting individuals from either transmitting or acquiring SARS-CoV-2 infection.

The Impact of Severe Acute Respiratory Syndrome Coronavirus 2 Vaccination and Infection on Neutralizing Antibodies: A Nation-wide Cross-sectional Analysis.

BACKGROUND: Neutralising antibodies (nAbs) play a critical role in the protection against severe COVID-19. In the era of vaccine boosters and repeated SARS-CoV-2 outbreaks, identifying individuals at risk represents a public health priority. METHODS: Relying on the Monaco COVID Public Health Programme, we evaluated nAbs from July 2021-June 2022 in 8,080 SARS-CoV-2 vaccinated and/or infected children and adults, at their inclusion visit. We stratified by infection status and investigated variables associated with nAbs using a generalised additive model. RESULTS: Infected and vaccinated participants had high and consistent nAbs (>800 IU/mL), which remained stable over time since injection, regardless of the number of vaccine doses, body mass index, sex, or age. By contrast, uninfected participants showed larger variability (two doses [V2] median 157.6; interquartile range [IQR] 43.3-439.1 IU/mL) versus three doses [V3] median 882.5; [829.5-914.8] IU/mL). NAbs decreased by 20% per month after V2 (adjusted ratio 0.80; 95%CI [0.79-0.82]), but remained stable after V3 (adjusted ratio 0.98; 95%CI [0.92-1.05]). CONCLUSIONS: Hybrid immunity provided stable, high and consistent nAbs over time. The benefit of boosters was marked to restore decaying nAbs in uninfected participants. NAbs could identify individuals at risk of severe COVID-19 and provide more targeted vaccine boosters' campaigns.

Fixed-Distance Model for Balloon Placement During Fluoroscopy-Free Resuscitative Endovascular Balloon Occlusion of the Aorta in a Civilian Population.

Importance: Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an innovative procedure in the treatment of noncompressible truncal hemorrhage. However, readily available fluoroscopy remains a limiting factor in its widespread implementation. Several methods have been proposed to perform REBOA without fluoroscopic guidance, and these methods were adapted predominantly from the military theater. Objective: To develop a method for performing REBOA in a civilian population using a standardized distance from a set point of entry. Design, Setting, and Participants: A retrospective study of whole-body computed tomographic (CT) scans from a cohort of 280 consecutive civilian trauma patients from University Hospitals of Lyon, France, was used to calculate the endovascular distances from both femoral arteries at the level of the upper border of the symphysis pubis to aortic zone I (descending thoracic aorta) and zone III (infrarenal aorta). These whole-body CT scans were performed between 2013 and 2015. Data were analyzed from July 16 to December 7, 2015. Main Outcomes and Measures: Two segments (1 per zone) common to all CT scans were isolated, and their location, length, prevalence in the cohort, and predicted prevalence in the general population were calculated by inverting 99% certainty tolerance limits. Results: Among the 280 trauma patients (140 men and 140 women) in this study, the mean (SD) height was 170.7 (8.7) cm, and the mean (SD) age was 38.8 (16.5) years. The common segment in zone I (414-474 mm) existed in all CT scans. The common segment in zone III (236-256 mm) existed in 99.6% and 97.9% of CT scans from the right and left femoral arteries, respectively. These segments are expected to exist in 98.7% (zone I) and 94.9% (zone III) of the general population. Conclusions and Relevance: Target distances for blind placement of REBOA exist with more than 94% prevalence in a civilian population. These findings support the expanded use of REBOA in emergency department and prehospital settings. Validation for safety and efficacy on cadaveric and clinical models is necessary.

Kendrick's extrication device and unstable pelvic fractures: Should a trochanteric belt be added? A cadaveric study.

INTRODUCTION: Pre-hospital pelvic stabilisation is advised to prevent exsanguination in patients with unstable pelvic fractures (UPFs). Kendrick's extrication device (KED) is commonly used to extricate patients from cars or crevasses. However the KED has not been tested for potential adverse effects in patients with pelvic fractures. The aim of this study was to examine the effect of the KED on pubic symphysis diastasis (SyD) with and without the use of a trochanteric belt (TB) during the extraction process following a MVC. MATERIALS AND METHODS: Left-sided "open-book" UPFs were created in 18 human cadavers that were placed in seven different positions simulating pre-extraction and extraction positions using the KED with and without a TB in two different positions (through and over the thigh straps). The SyD was measured using anteroposterior radiographs. The effects of the KED with and without TB, on the SyD, were evaluated. RESULTS: The KED alone resulted in a non-significant increase of the SyD compared to baseline, whereas the addition of a TB to the KED resulted in a significant reduction of the SyD (p<0.001). The TB through the straps provided a significantly better reduction than the TB over the straps in the extracted position (p<0.05). CONCLUSION: Our study demonstrated that a TB in combination with the KED on UPFs is an effective way to achieve early reduction. The addition of the TB in combination with the KED could be considered for Pre-Hospital Trauma Life Support (PHTLS) training protocols.

Clamshell incision versus left anterolateral thoracotomy. Which one is faster when performing a resuscitative thoracotomy? The tortoise and the hare revisited.

BACKGROUND: The clamshell incision (CI) offers a better exposure than the left anterolateral thoracotomy (LAT) as a resuscitative thoracotomy. Most surgeons will have to manage a heart wound only once or twice in their career. The patient's survival depends on how fast the surgeon can control the heart wound; however, it is unclear which of the two incisions allows for faster control in the hands of inexperienced surgeons. The aim of this study was to compare the time needed to access and control a standardized stab wound to the right ventricle, by inexperienced surgical trainees, by LAT or CI; we hypothesized that the CI does not take longer than the LAT. METHODS: Sixteen residents were shown a video on how to perform both procedures. They were randomly assigned to control a standardized stab wound of the right ventricle on perfused human cadavers by LAT (n = 8) or CI (n = 8). Access time (skin to maximal exposure), control time (maximal exposure until control of the heart wound) and total time (the sum of access and control times) were recorded. RESULTS: Total time was 6.62 min [3.20-8.14] (median [interquartile range]) for LAT and 4.63 min [3.17-6.73] for CI (p = 0.46). Access time was 2.39 min [1.21-2.76] for LAT and 2.33 min [1.58-4.86] for CI (p = 0.34). Control time was 4.16 min [2.32-5.49] for LAT and 1.85 min [1.38-2.23] for CI (p = 0.018). CONCLUSIONS: The time needed from skin incision until cardiac wound control via CI was not longer than via LAT and the easier control of the cardiac wound when using CI was confirmed.

Effect of continuous oxygen insufflation on induced-gastric air volume during cardiopulmonary resuscitation in a cadaveric model.

BACKGROUND: The main objective of this study was to compare the volume of gas insufflated in the stomach with continuous external chest compressions plus continuous oxygen insufflation (C-CPR) versus standard-CPR (S-CPR) which alternates external chest compressions and synchronized positive insufflations through a bag-valve-mask with a 30/2 ratio. The secondary objective was to compare upper airway pressures (intratracheal and intramask) generated during continuous oxygen insufflation. MATERIAL AND METHODS: Open, prospective, randomized, cross over, comparative, non-inferiority study. CPR was performed for six minutes periods, on seven fresh human corpses, with C-CPR or S-CPR in a random order. Before each CPR period, the stomach was completely emptied through the gastrostomy tube, and then 200 mL of air was injected in the stomach to be sure it was not collapsed. The gastric volume was measured at the end of each intervention. Intratracheal and intramask pressures were recorded continuously during C-CPR. Results were provided as mean ± standard deviation. Statistical analyses were done with a paired student t test. RESULTS: Induced-gastric inflation was lower with C-CPR (221 ± 130 mL) than with S-CPR (5401 ± 2208 mL, p = 0.001). Throughout C-CPR, no difference was found between the intratracheal and intramask pressures (4.4 ± 1.2; 4.0 ± 0.8 cmH2O, respectively, p = 0.45). CONCLUSION: This human cadaver study demonstrates that continuous oxygen insufflation induced less gastric inflation than intermittent insufflation during CPR.

Bilateral anterior thoracotomy (clamshell incision) is the ideal emergency thoracotomy incision: an anatomic study.

BACKGROUND: Emergency thoracotomy (ET) is a procedure that provides rapid access to intrathoracic structures for thoracic trauma patients arriving at the hospital in extremis. This study assesses the accessibility of intrathoracic structures provided by six different ET incisions. We hypothesize that the bilateral anterior thoracotomy ("clamshell" incision) provides the most rapid and definitive accessibility to intrathoracic structures. METHODS: Six ET incision types (left anterolateral thoracotomy, right anterolateral thoracotomy, left 2nd intercostal space incision, left 3rd intercostal space incision, median sternotomy, and bilateral anterior thoracotomy) were performed multiple times on eight cadavers. The critical intrathoracic structures were assessed for rapid accessibility and control, and they were characterized as "readily accessible," "accessible," and "inaccessible" on anatomic accessibility maps. RESULTS: Median sternotomy provided better access to intrathoracic structures than left and right anterior thoracotomies. Definitive control of the origin of the left subclavian artery was difficult with left 2nd or 3rd intercostal space incisions. Bilateral anterior thoracotomy, the clamshell incision, was easy to perform and gave superior access to all intrathoracic structures. CONCLUSIONS: In severe thoracic trauma, specific injuries are unknown, even if they can be anticipated. The best incision is therefore one that provides the most rapid and definitive access to all thoracic structures for assessment and control. While the right and left anterolateral incisions may be successfully employed by surgeons with extensive experience in ET, the clamshell incision remains the superior incision choice.

Comparison of thoracic wall behavior in large animals and human cadavers submitted to an identical ballistic blunt thoracic trauma.

BACKGROUND: Several models of ballistic blunt thoracic trauma are available, including human cadavers and large animals. Each model has advantages and disadvantages regarding anatomy and physiology, but they have not been compared with identical ballistic aggression. METHODS: To compare thoracic wall behavior in 40-kg pigs and human cadavers, the thorax of 12 human cadavers and 19 anesthetized pigs were impacted with two different projectiles at different speeds. On the thoracic wall, the peak acceleration, peak velocity, maximal compression, viscous criterion, and injury criteria (e.g. abbreviated injury scale and number of rib fractures) were recorded. The correlations between these motion and injury parameters and the blunt criterion were compared between the two groups. The bone mineral density of each subject was also measured. RESULTS: The peak acceleration, the peak velocity and the viscous criterion were significantly higher for the pigs. The AIS and the number of rib fractures were significantly higher for human cadavers. The bone mineral density was significantly higher for cadavers, but was, for the two groups, significantly lower than for 30-year-old human. CONCLUSION: The motion of the pig's thoracic wall is greater than that of the human cadaver, and the severity of the impact is always greater for human cadavers than for pigs. In addition, pig bone is more elastic and less brittle than older human cadaver bone. Due to the bone mineral density, the thoracic wall of human adults should be more rigid and more resistant than the thoracic wall of human cadavers or pigs.

The flap by flap dissection in terminal ballistic applied to less lethal weapons.

Medical examiners often have to solve questions such as firing distance and bullet trajectory for lethal weapons. Knowledge in the field of terminal ballistics has increased during the last 30 years and layer by layer dissection reveals superficial wounds that can be linked with the permanent cavity. At the end of the 1990s, terminal ballistics also focused on less lethal weapons and their wounds. Here, 2 different less lethal weapons with single bullets were tested on nonembalmed and undressed cadavers (N = 26) at different ranges and speeds. We have developed a technique for dissection which we call flap by flap dissection that reveals the advantage of the bullet-skin-bone entity, the absence of wounds linking its components and range of less lethal weapons.

Less-lethal hybrid ammunition wounds: a forensic assessment introducing bullet-skin-bone entity.

Agencies all around the world now use less-lethal weapons with homogeneous missiles such as bean bag or rubber bullets. Contusions and sometimes significant morbidity have been reported. This study focuses on wounds caused by hybrid ammunition with the pathologists' flap-by-flap procedure. Twenty-four postmortem human subjects were used, and lesions caused on frontal, temporal, sternal, and left tibial regions by a 40-mm hybrid ammunition (33 g weight) were evaluated on various distance range. The 50% risk of fractures occurred at 79.2 m/sec on the forehead, 72.9 m/sec on the temporal, 72.5 m/sec on the sternum, and 76.7 m/sec on the tibia. Skin lesions were not predictors of bone fracture. There was no correlation between soft and bone tissue observed lesions and impact velocity (correlated to distance range). Lesions observed with hybrid ammunition were the result of bullet-skin-bone entity as the interaction of the projectile on skin and bone tissues.

First clinical study of a new virus-inhibiting surgical glove.

QUESTION UNDER STUDY: Prospective clinical study to evaluate the tolerance, ergonomics and glove barrier value (mechanical resistance to breach) of a new surgical glove sandwiching droplets of a disinfecting agent between two layers of a synthetic elastomer (G-VIR) able to inactivate viruses when breached. METHODS: 100 surgical procedures were performed by six surgeons wearing G-VIR on 100 patients included after informed consent. Procedures were classified into laparoscopic (n = 28) or open surgery (n = 72); open surgery being subdivided either into superficial (n = 33) and deep (n = 39) or into hernia (n = 32) and non hernia (n = 40). The ergonomics and tolerance of the glove were evaluated by the surgeons using a questionnaire. Patients were clinically evaluated daily during hospitalization and once between the 4th to 6th postoperative week. All used gloves underwent a water leak test to detect any breach. RESULTS: 834 G-VIR gloves were used, 456 by the first surgeon and 378 by the assistant surgeon, resulting in 195 exposures, lasting 288 operator-hours (OH). No adverse effect on patients and/or surgeons linked to G-VIR could be observed. Ergonomics of G-VIR has been evaluated as equivalent as standard double gloving, excepted for donning which was more difficult (P <0.05). The breach rate per glove (BRpG) amounted to 1.8%. According to breach rate per operator-hour (BRpOH), surgical procedures could be categorized in low (laparoscopy), middle (non hernia and hernia superficial) and high (hernia deep) risk procedures. CONCLUSIONS: G-VIR gloving offers an excellent mechanical protection, is suitable for daily surgical practice and maybe recommended in high risk surgical procedures.

Anticipated detection of imminent surgeon-patient barrier breaches. A prospective randomized controlled trial using an indicator underglove system.

The double gloving indicator underglove system (IUS) is based on a colored detection of the outer glove perforation. Our objective was to determine the IUS efficiency to detect outer glove perforations and to reduce the risks of blood and body fluids exposure, warning the surgeon before the breach of the surgeon-patient barrier (SPB). A series of 100 visceral surgical procedures were randomly assigned to either double (IUS) or single gloving. The noticed glove perforations (using the water test method) and the IUS efficiency were analyzed in 99 procedures. In 49 single-gloving procedures, 19 perforations were noticed: one was immediately perceived (perceived accidental exposure, PAE); 3 were discovered as the gloves were being removed, and 15 were undetected before the water test (unperceived prolonged contact, UPC). In 50 double-gloving procedures (IUS), 16 perforations were noticed, all of them involving only the outer glove: the IUS allowed immediate detection of 3 perforations without any blood exposure; 13 other perforations went undetected but without any UPC. In conjunction with the protective quality of double gloving, the IUS allows detection of significant breaches of the outer glove before the breach of the SPB.

Ballistic study of the SAPL GC27 gun: is it really "nonlethal"?

To evaluate the potential dangers of the "nonlethal" 12-gauge single-shot handgun SAPL GC27 with Fun-Tir (FT) and mini-Gomm-Cogne (mGC) ammunition, a ballistic study was performed with both types of ammunition. Nine unembalmed human corpses covered with a cloth sheet were shot through the right and left pectoral regions. With the mGC ammunition, rib fractures were observed when the firing range was less than 2 meters, skin perforation when the range was less than 1.5 meters, with lung injuries at less than 0.2 meter; the heart and the aorta were lacerated at contact range (0 meter). No skin perforation was observed with the FT ammunition, but rib fractures were observed when it was fired at up to 2 meters. Our study shows that the mGC ammunition, shot by the CG27 firearm, can be lethal at contact range and that pellets penetrate the skin at ranges of less than 1 meter. These results led us to conclude that this weapon is too dangerous to be marketed as a "nonlethal" weapon. The term "reduced wounding power weapon" is preferable.