Explore the vast range of titles available.

Background: Meningococcal disease is caused by the bacterium Neisseria meningitidis, which is a commensal in the human upper airways. Teenagers and young adults are the main reservoir for the bacteria. The aim of this study was to assess the prevalence of meningococcal carriage and risk factors for carriage among high school and university students in Northwestern Ethiopia. Methods: Oropharyngeal swabs and buccal samples were collected and stored on Whatman FTA-cards pending PCR analysis. DNA was extracted and a Multiplex TaqMan® custom assay was performed to detect N. meningitidis bacteria using the genes sodC and porA as species-specific targets. Genogrouping was performed for the samples positive for N. meningitidis using multiplex real-time PCR for the groups A, B, C, W, Y and X using a Rotor-Gene Q real-time PCR system. Result: Out of the 1025 participants, 52% were female with a mean and median ages of 17 and 16 years, respectively. A total of 19 throat swab samples were positive for N. meningitidis giving an overall carriage rate of 1.9%. The carriage rate of N. meningitidis among high school students was 1.0% and 2.5% for the University students, respectively (p-value = 0.051). A significantly higher carriage rate was observed among participants with the age of 23 and above (p-value = 0.021). Among the N. meningitidis isolates, 16 out of 19 were non-groupable, while 3 were groupable. Of the groupable isolates, two belonged to group W and one to group B. Among the risk factors assessed, sharing a glass or bottle for drinking (86%), not having received a meningitis vaccine (66%), and having had a tonsillectomy (47%), were the most common risk factors. Among participants with positive meningococcal carriage, 89% of them have shared glass for drinking and 74% of them had not received previous meningococcal vaccine, while this figure is reduced to 66% and 65%, respectively among the non-carriers. Conclusion: The overall meningococcal carriage rate was lower than those reported in previous Ethiopian studies, with age as the only identified risk factor.

Carrying side loads often occurs during activities of daily living. As walking is most unstable mediolaterally, side load carriage may further compromise gait biomechanics, especially for transtibial amputees (TTAs). This study investigated the effects of side load carriage on gait kinetics during steady-state walking to determine which side, intact or prosthetic, TTAs should carry a load. Twelve unilateral TTAs wore a passive-elastic foot and carried a side load of 13.6 kg while walking at their self-selected speed. Kinetic metrics, including ground reaction force peaks and impulses, loading and unloading rates, and joint moments and powers, were analyzed. TTAs had smaller propulsive forces on their intact limb during the prosthetic side load condition. During the intact side load condition, they had smaller hip flexor moment in late stance and smaller knee flexor moment at the end of swing on their intact limb. They had higher hip and knee abductor moments on their intact limb and prosthetic limb in early and late stance during the contralateral side load condition. TTAs generated higher hip extensor power at weight acceptance during the ipsilateral side load. Significant interactions were observed in hip extensor power and abductor moment, suggesting strong associations between hip extensor power generation and the ipsilateral side load and between hip abductor moment and the contralateral side load. These mixed results demonstrate some kinetic changes due to side load carriage and suggest that the side TTAs should carry a load depends on the desired effects, primarily on their intact limb.

Numerical study was carried out to analyze the effect of door opening scenario on the smoke propagation in metro tunnel fires. The smoke back-layering length, critical velocity, and temperature distribution were studied under a total of 8 working conditions. Results show that the opening of emergency exit doors could result in a shorter smoke back-layering length in the train compartment. In such conditions, a smaller driving force was needed to approach the critical velocity. On the other hand, the high temperature area of the tunnel evacuation platform would change under different opening scenarios. The research result could be used as a deeper understanding of the smoke propagation of metro fire and a reference for the formulation of smoke control.

The content of the article is based on the classical provisions of mechanics (the Dalembert principle) for non-ideal communication. The analytical proof is given that the linear acceleration of the car with its equally accelerated movement along the descent part of the sorting slide depends on the force under the influence of which the car rolls down the slope of the slide, the strength of resistances of all kinds, on the reduced mass of the car with the load, taking into account the moment of inertia of the rotating parts. At the same time, the results of calculations proved that taking into account the mass of rotating parts practically does not affect the acceleration of the carriage along the slope of the slide. The acceleration formulas and the resulting forces acting on the car are presented in the generally accepted notation and in the usual sense, followed by the calculated data.

To determine the duration of carbapenemase-producing Enterobacteriaceae (CPE) carriage, we studied 21 CPE carriers for »1 year. Mean carriage duration was 86 days; probability of decolonization in 1 year was 98.5%, suggesting that CPE-carriers' status can be reviewed yearly. Prolonged carriage was associated with use of antimicrobial drugs.

In 2019, a community-based, cross-sectional carriage survey and a seroprevalence survey of 1,216 persons 1-55 years of age were conducted in rural Vietnam to investigate the mechanism of diphtheria outbreaks. Seroprevalence was further compared with that of an urban area that had no cases reported for the past decade. Carriage prevalence was 1.4%. The highest prevalence, 4.5%, was observed for children 1-5 years of age. Twenty-seven asymptomatic Coerynebacterium diphtheriae carriers were identified; 9 carriers had tox gene-bearing strains, and 3 had nontoxigenic tox gene-bearing strains. Child malnutrition was associated with low levels of diphtheria toxoid IgG, which might have subsequently increased child carriage prevalence. Different immunity patterns in the 2 populations suggested that the low immunity among children caused by low vaccination coverage increased transmission, resulting in symptomatic infections at school-going age, when vaccine-induced immunity waned most. A school-entry booster dose and improved infant vaccination coverage are recommended to control transmissions.

Abstract Background The thirteen-valent pneumococcal conjugate vaccine (PCV13) is not included in the national immunization program and is administered voluntarily with informed consent in China. In preparation for assessing the impact of pilot introduction in Hainan Province, we conducted a carriage study among children under 5 years of age from four locations in Hainan Province, China. Methods From March to June 2022, nasopharyngeal (NP) swabs, collected from healthy children aged younger than 59 months who lived in the 4 different locations (Haikou, Wanning, Baisha and Qiongzhong) in Hainan Province, were tested for pneumococcus using conventional culture. Pneumococcal isolates were serotyped using the Quellung reaction. Risk factors associated with pneumococcal colonization were assessed using univariate analysis and multivariable logistic regression adjusting for age, daycare attendance and other factors. Results Pneumococcus was isolated in 710 (30.4%) of the 2333 children enrolled. Of 737 pneumococci, 29 serotypes were identified; 60.9% were PCV13 serotypes; the most common vaccine serotypes were 6B (20.4%), 19F (13.0%), 6A (11.9%) and 23F (6.1%); and the most common nonvaccine serotypes were 23A (12.9%), 34 (6.1%) and nontypeable (NT) pneumococci (5.6%). Children vaccinated with PCV13 had lower carriage (17.7% vs 32.5%; P = 0.0001) and fewer PCV13 serotypes (41.9% vs 62.7%; P = 0.0017) compared to unimmunized children. After adjustment, NP carriage was higher among children attending daycare (aOR = 2.3, 95% CI: 1.7–3.2), living in rural areas (aOR = 1.4, 95% CI: 1.1–1.8), living with siblings (aOR = 1.3, 95% CI: 1.0–1.6) and whose mothers had completed senior high/technical secondary school (aOR = 1.5, 95% CI: 1.1–2.0). In contrast, completion of 3–4 doses of PCV13 were associated with a lower carriage rate (aOR = 0.6, 95% CI: 0.4–0.9). Conclusions We established the baseline of pneumococcal carriage, serotype distribution and PCV13 immunization rates among healthy children under 5 years of age in Hainan Province, prior to the introduction of PCV13 into the national immunization program. The high proportion of PCV13 serotypes suggests that PCV13 introduction will likely have a substantial impact on pneumococcal carriage in Hainan Province. Graphical Abstract

The rates of nasopharyngeal meningococcal carriage in healthcare workers are unknown. Meningococcal vaccine is recommended for risk groups but healthcare workers are not included in risk groups for many countries. Herein, we aimed to investigate the nasopharyngeal meningococcal carriage rates, basal and after one dose of Men-ACWY-DT vaccine response on the 30th day by evaluating meningococcus IgG antibody levels and decolonization at month six after vaccination among the detected carriers. Nasopharyngeal swab samples were taken before vaccination to evaluate meningococcal carriage in healthcare workers. All participants received a single dose of Men-ACWY-DT vaccine. Serum samples were collected immediately before vaccination and again on day 30 post-vaccination. Antibodies in the stored sera were analyzed using the ELISA method. Participants who were determined to carry meningococci at the initial visit underwent another round of nasopharyngeal swab tests six months post-vaccination to check for decolonization. Between November 2020 and May 2021, we evaluated samples from 100 physicians [52 % females, 28.28 ± 4.45 (min: 24, max: 49)]. The majority of the physicians worked in the emergency department (45 %), followed by the infectious diseases clinic (14 %). Fifty-eight physicians had a history of at least one contact with a meningococcus-infected patient, and 53 (91.4 %) had used prophylactic antibiotics at least once due to this exposure. None of the study group nasopharyngeal swab cultures were positive for Neisseria meningitidis. Before the Men-ACWY-DT vaccine, anti-meningococcus IgG positivity was detected in the serum samples of only 3 (3 %) participants. By day 30 after vaccination, 48 % of participants showed positive for antibodies. As we didn’t detect nasopharyngeal carriage in any participants, we didn’t evaluate decolonization among carriers six months post-vaccination. Notably, detection of antibodies was evident in about half of the participants on day 30 after receiving a single dose of the Men-ACWY-DT vaccine.