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Background: Serial interval (SI) is one of the most important parameter for COVID-19 modelling purposes as it is related to the reproduction rate of the infection. The first meta-analysis of serial interval were performed with a range of uncertainty in the estimate. This meta-analysis aimed to reduce the uncertainty estimates by assessing publications over a longer period. Methods: A literature search was performed for articles published between 1st December 2019 and 15th February 2022. It retrieved 117 eligible studies containing some 80 for 90 serial interval estimates. A random effects model was used. Heterogeneity was checked. To detect a publication bias, a funnel plot was performed using an Egger’s test. Results: For alpha variant, the serial interval was estimated at 5.17 days (95% CI = 4.87 – 5.47) with a significant heterogeneity (I2 = 97.1%). The meta-analysis did not exhibit evident publication bias (Egger’s test = −0.55, p = 0.58). The meta-analysis allowed for reducing uncertainty in estimating the serial interval, although subgroup analysis did not reduce it sufficiently and showed that studies using a gamma distribution of serial intervals exhibited the highest estimate of 5.6 days. Compared to the other variants of concern, alpha serial interval estimate was bigger than delta, 4.07 days, and omicron, 3.06 days. Conclusion: The meta-analysis was carried out as a real-time monitoring of this parameter to make a choice and a rapid assessment of the control measures implemented, and the effectiveness of the vaccination campaign. The meta-analysis was unable to provide a suitable estimate of serial intervals for COVID-19 modelling purposes although its uncertainty was reduced. Furthermore, serial intervals estimate for alpha variant was close to earlier reports and lower than previous publications, respectively. Another limitation is, that meta-analysis of COVID pandemic studies in principle contains and produces itself a significant source of heterogeneity.

Background: During his life, Beethoven faced a lot of personal problems and diseases that could lead to a prolonged period of serious mental disorder. The aim of this work is to study the link between the distribution of pitch frequencies observed in 101 movements of 32 sonatas and four periods of his compositional style. Methods: The 32 sonatas for piano were chosen because they were composed during the three periods usually considered to reflect Beethoven’s career. A hierarchical generalized additive model was performed to regress the frequency of pitches with Musical Instrument Digital Interface (MIDI) pitches, periods of composition, degrees, rests, and length of the sonata’s movements. Results: The median frequency of pitches was higher during Beethoven’s time of mental distress. This period appeared as transitory between the bright Promethean period and the fullness of the final Ethereal period. This change in the expression of Beethoven’s creativity could well have played the role of a self-therapy. Conclusion: From this singular account of Beethoven’s history of mental problems and his way of dealing with them, it could be concluded that the stimulation of their musical creativity could be beneficial for psychiatrically patients with mental health issues. It also suggests that some mechanisms such as the application of hysteresis to cognitive function at a time of mental distress, may indicate new research avenues in the treatment of mental diseases.

Background: Serotype 1 was the most prevalent pneumococcal meningitis serotype encountered in Niger over the period 2003-2011 (pre-vaccination era), accounting for 45.3% of infections. Methods: Multiple locus VNTR analysis (MLVA) was used to create a genotypic snapshot of a representative subset of the pneumococcal population of serotype 1. Results: MLVA using 16 markers revealed a homogeneous genetic background of pneumococci serotype 1 from Niger, which clustered with few serotype 1 pneumococci from some African countries, while other African countries displayed different clonal complexes. DNA from Niger and from other African countries were different from pneumococci serotype 1 from European countries. Conclusions: MLVA-typing revealed a low genetic diversity among pneumococci serotype 1 from meningitis cases in Niger in the pre-vaccination era. [ABSTRACT FROM AUTHOR]

A letter to the editor about an increase in cases of Neisseria meningitidis in Niger in 2010 is presented.

Objective:Detection of meningococcal carriers is key to understanding the epidemiology of Neisseria meningitidis, yet no gold standard has been established. Here, we directly compare two methods for collecting pharyngeal swabs to identify meningococcal carriers. Methods:We conducted cross-sectional surveys of schoolchildren at multiple sites in Africa to compare swabbing the posterior pharynx behind the uvula (U) to swabbing the posterior pharynx behind the uvula plus one tonsil (T). Swabs were cultured immediately and analyzed using molecular methods. Results:One thousand and six paired swab samples collected from schoolchildren in four countries were analyzed. Prevalence of meningococcal carriage was 6.9% (95% CI: 5.4-8.6%) based on the results from both swabs, but the observed prevalence was lower based on one swab type alone. Prevalence based on the T swab or the U swab alone was similar (5.2% (95% CI: 3.8-6.7%) versus 4.9% (95% CI: 3.6-6.4%) respectively (p=0.6)). The concordance between the two methods was 96.3% and the kappa was 0.61 (95% CI: 0.50-0.73), indicating good agreement. Conclusions:These two commonly used methods for collecting pharyngeal swabs provide consistent estimates of the prevalence of carriage, but both methods misclassified carriers to some degree, leading to underestimates of the prevalence. [ABSTRACT FROM AUTHOR]

Objective: To investigate potential risk factors for acquisition in seven countries of the meningitis belt., Methods: Households were followed up every 2 weeks for 2 months, then monthly for a further 4 months. Pharyngeal swabs were collected from all available household members at each visit and questionnaires completed. Risks of acquisition over the whole study period and for each visit were analysed by a series of logistic regressions., Results: Over the course of the study, acquisition was higher in: (i) 5-to 14-year olds, as compared with those 30 years or older (OR 3.6, 95% CI 1.4-9.9); (ii) smokers (OR 3.6, 95% CI 0.98-13); and (iii) those exposed to wood smoke at home (OR 2.6 95% CI 1.3-5.6). The risk of acquisition from one visit to the next was higher in those reporting a sore throat during the dry season (OR 3.7, 95% CI 2.0-6.7) and lower in those reporting antibiotic use (OR 0.17, 95% CI 0.03-0.56)., Conclusions: Acquisition of meningococcal carriage peaked in school age children. Recent symptoms of sore throat during the dry season, but not during the rainy season, were associated with a higher risk of acquisition. Upper respiratory tract infections may be an important driver of epidemics in the meningitis belt., (© 2019 John Wiley & Sons Ltd.)

The pattern of epidemic meningococcal disease in the African meningitis belt may be influenced by the background level of population immunity but this has been measured infrequently. A standardised enzyme-linked immunosorbent assay (ELISA) for measuring meningococcal serogroup A IgG antibodies was established at five centres within the meningitis belt. Antibody concentrations were then measured in 3930 individuals stratified by age and residence from six countries. Seroprevalence by age was used in a catalytic model to determine the force of infection. Meningococcal serogroup A IgG antibody concentrations were high in each country but showed heterogeneity across the meningitis belt. The geometric mean concentration (GMC) was highest in Ghana (9.09 μg/mL [95% CI 8.29, 9.97]) and lowest in Ethiopia (1.43 μg/mL [95% CI 1.31, 1.57]) on the margins of the belt. The force of infection was lowest in Ethiopia (λ = 0.028). Variables associated with a concentration above the putative protective level of 2 μg/mL were age, urban residence and a history of recent vaccination with a meningococcal vaccine. Prior to vaccination with the serogroup A meningococcal conjugate vaccine, meningococcal serogroup A IgG antibody concentrations were high across the African meningitis belt and yet the region remained susceptible to epidemics.

Background: Serotype 1 was the most prevalent pneumococcal meningitis serotype encountered in Niger over the period 2003-2011 (pre-vaccination era), accounting for 45.3% of infections., Methods: Multiple locus VNTR analysis (MLVA) was used to create a genotypic snapshot of a representative subset of the pneumococcal population of serotype 1., Results: MLVA using 16 markers revealed a homogeneous genetic background of pneumococci serotype 1 from Niger, which clustered with few serotype 1 pneumococci from some African countries, while other African countries displayed different clonal complexes. DNA from Niger and from other African countries were different from pneumococci serotype 1 from European countries., Conclusions: MLVA-typing revealed a low genetic diversity among pneumococci serotype 1 from meningitis cases in Niger in the pre-vaccination era., (© The Author 2015. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)