Concussion in sport: what is known and what is new?

The aim of this article was to summarise the latest definition of concussion, signs of concussion, as well as important facts on recovery and graduated return to play, for different age groups. New technologies available to the sports physician are listed.Keywords: concussion, diagnosis, return to play, sign

Solvability of a hybrid model for a vertical slender structure

We consider the solvability of a hybrid model for the vibration of a vertical slender structure mounted on an elastic seating. The slender structure is modeled as a Rayleigh beam and gravity is taken into account. The seating and foundation block are modeled as rigid bodies connected by elastic springs with damping mechanisms. We show how an existence result for a general linear vibration problem in variational form may be applied to the weak variational problem for this system

The relationship between functional movement analysis and lowerbody injury rates in adolescent female football players

Objective. To determine whether a relationship exists between the functional movement analysis (FMA) score and lower-body injury rates in high-performance adolescent female football players.Method. Observations included a baseline FMA score and medical injury reports. Data were collected from 24 players’ injury and illness records over a 38-week training period. All football injuries requiring medical attention (including stiffness, strains, contusions and sprains) and/or the removal from a session, leading to training restriction, were included in the study. Off-season weeks were excluded. Pearson’s product-moment correlation coefficient was calculated to assess the strength of the linear relationship between the FMA score and the number of medical visits, and between the number of medical visits and the number of training-restriction days.Results. There was no evidence of a relationship between the FMA score and injury risk in teenage female football players (r=0.016; p=0.940). A strong indication of a cyclical season in the training schedule was noticed over the 38-week study period. A substantive negative correlation (r=-0.911; p=0.032) was seen in the number of medical visits compared with the training-restriction days. Injuries during two peak periods could have resulted from overuse, increased training load, stress and overtraining.Conclusion. It could not be shown that a high FMA score was associated with a lower risk of injury. The ultimate goal is thus to reduce recurrent injury in players with a high FMA count. The regular medical visits observed suggest that player condition is maintained by means of reducing injury and managing training-restriction days. Our findings are in accordance with previous studies in terms of the lower limb being the most frequent region of injury, specifically the knee. This study supports previous suggestions that it is essential to develop a prevention strategy to measure trauma and recovery

Reclaiming comprehensive public health

Global and national responses to the COVID-19 pandemic highlight a long-standing tension between biosecurity-focused, authoritarian and sometimes militarised approaches to public health and, in contrast, comprehensive, social determinants, participatory and rights-based approaches. Notwithstanding principles that may limit rights in the interests of public health and the role of central measures in some circumstances, effective public health in a protracted pandemic like COVID-19 requires cooperation, communication, participatory decision-making and action that safeguards the Siracusa principles, respect for people’s dignity and local-level realities and capacities. Yet there is mounting evidence of a dominant response to COVID-19 where decisions are being made and enforced in an overcentralised, non-transparent, top-down manner, often involving military coercion and abuse in communities, even while evidence shows the long-term harm to public health and human rights. In contrast, experiences of comprehensive, equity-focused, participatory public health approaches, which use diverse sources of knowledge, disciplines and capabilities, show the type of public health approach that will be more effective to meet the 21st century challenges of pandemics, climate, food and energy crises, growing social inequality, conflict and other threats to health

Change in Composition of the Anopheles Gambiae Complex and its Possible Implications for the Transmission of Malaria and Lymphatic Filariasis in North-Eastern Tanzania.

A dramatic decline in the incidence of malaria due to Plasmodium falciparum infection in coastal East Africa has recently been reported to be paralleled (or even preceded) by an equally dramatic decline in malaria vector density, despite absence of organized vector control. As part of investigations into possible causes for the change in vector population density, the present study analysed the Anopheles gambiae s.l. sibling species composition in north-eastern Tanzania. The study was in two parts. The first compared current species complex composition in freshly caught An. gambiae s.l. complex from three villages to the composition reported from previous studies carried out 2-4 decades ago in the same villages. The second took advantage of a sample of archived dried An. gambiae s.l. complex specimens collected regularly from a fourth study village since 2005. Both fresh and archived dried specimens were identified to sibling species of the An. gambiae s.l. complex by PCR. The same specimens were moreover examined for Plasmodium falciparum and Wuchereria bancrofti infection by PCR. As in earlier studies, An. gambiae s.s., Anopheles merus and Anopheles arabiensis were identified as sibling species found in the area. However, both study parts indicated a marked change in sibling species composition over time. From being by far the most abundant in the past An. gambiae s.s. was now the most rare, whereas An. arabiensis had changed from being the most rare to the most common. P. falciparum infection was rarely detected in the examined specimens (and only in An. arabiensis) whereas W. bancrofti infection was prevalent and detected in all three sibling species. The study indicates that a major shift in An. gambiae s.l. sibling species composition has taken place in the study area in recent years. Combined with the earlier reported decline in overall malaria vector density, the study suggests that this decline has been most marked for An. gambiae s.s., and least for An. arabiensis, leading to current predominance of the latter. Due to differences in biology and vectorial capacity of the An. gambiae s.l. complex the change in sibling species composition will have important implications for the epidemiology and control of malaria and lymphatic filariasis in the study area

Sequence-based prediction for vaccine strain selection and identification of antigenic variability in foot-and-mouth disease virus

Identifying when past exposure to an infectious disease will protect against newly emerging strains is central to understanding the spread and the severity of epidemics, but the prediction of viral cross-protection remains an important unsolved problem. For foot-and-mouth disease virus (FMDV) research in particular, improved methods for predicting this cross-protection are critical for predicting the severity of outbreaks within endemic settings where multiple serotypes and subtypes commonly co-circulate, as well as for deciding whether appropriate vaccine(s) exist and how much they could mitigate the effects of any outbreak. To identify antigenic relationships and their predictors, we used linear mixed effects models to account for variation in pairwise cross-neutralization titres using only viral sequences and structural data. We identified those substitutions in surface-exposed structural proteins that are correlates of loss of cross-reactivity. These allowed prediction of both the best vaccine match for any single virus and the breadth of coverage of new vaccine candidates from their capsid sequences as effectively as or better than serology. Sub-sequences chosen by the model-building process all contained sites that are known epitopes on other serotypes. Furthermore, for the SAT1 serotype, for which epitopes have never previously been identified, we provide strong evidence - by controlling for phylogenetic structure - for the presence of three epitopes across a panel of viruses and quantify the relative significance of some individual residues in determining cross-neutralization. Identifying and quantifying the importance of sites that predict viral strain cross-reactivity not just for single viruses but across entire serotypes can help in the design of vaccines with better targeting and broader coverage. These techniques can be generalized to any infectious agents where cross-reactivity assays have been carried out. As the parameterization uses pre-existing datasets, this approach quickly and cheaply increases both our understanding of antigenic relationships and our power to control disease

Risk factors for oesophageal, lung, oral and laryngeal cancers in black South Africans

The authors used data collected from 1995 to 1999, from an on-going cancer case–control study in greater Johannesburg, to estimate the importance of tobacco and alcohol consumption and other suspected risk factors with respect to cancer of the oesophagus (267 men and 138 women), lung (105 men and 41 women), oral cavity (87 men and 37 women), and larynx (51 men). Cancers not associated with tobacco or alcohol consumption were used as controls (804 men and 1370 women). Tobacco smoking was found to be the major risk factor for all of these cancers with odds ratios ranging from 2.6 (95% CI 1.5–4.5) for oesophageal cancer in female ex-smokers to 50.9 (95% CI 12.6–204.6) for lung cancer in women, and 23.9 (95% CI 9.5–60.3) for lung cancer and 23.6 (95% CI 4.6–121.2) for laryngeal cancer in men who smoked 15 or more grams of tobacco a day. This is the first time an association between smoking and oral and laryngeal cancers has been shown in sub-Saharan Africa. Long-term residence in the Transkei region in the southeast of the country continues to be a risk factor for oesophageal cancer, especially in women (odds ratio=14.7, 95% CI 4.7–46.0), possibly due to nutritional factors. There was a slight increase in lung cancer (odds ratio=2.9, 95% CI 1.1–7.5) in men working in ‘potentially noxious’ industries. ‘Frequent’ alcohol consumption, on its own, caused a marginally elevated risk for oesophageal cancer (odds ratio=1.7, 95% CI 1.0–2.9, for women and odds ratio=1.8, 95% CI 1.2–2.8, for men). The risks for oesophageal cancer in relation to alcohol consumption increased significantly in male and female smokers (odds ratio=4.7, 95% CI=2.8–7.9 in males and odds ratio=4.8, 95% CI 3.2–6.1 in females). The above results are broadly in line with international findings