Entomological Surveillance of Behavioural Resilience and Resistance in Residual Malaria Vector Populations.

The most potent malaria vectors rely heavily upon human blood so they are vulnerable to attack with insecticide-treated nets (ITNs) and indoor residual spraying (IRS) within houses. Mosquito taxa that can avoid feeding or resting indoors, or by obtaining blood from animals, mediate a growing proportion of the dwindling transmission that persists as ITNs and IRS are scaled up. Increasing frequency of behavioural evasion traits within persisting residual vector systems usually reflect the successful suppression of the most potent and vulnerable vector taxa by IRS or ITNs, rather than their failure. Many of the commonly observed changes in mosquito behavioural patterns following intervention scale-up may well be explained by modified taxonomic composition and expression of phenotypically plastic behavioural preferences, rather than altered innate preferences of individuals or populations. Detailed review of the contemporary evidence base does not yet provide any clear-cut example of true behavioural resistance and is, therefore, consistent with the hypothesis presented. Caution should be exercised before over-interpreting most existing reports of increased frequency of behavioural traits which enable mosquitoes to evade fatal contact with insecticides: this may simply be the result of suppressing the most behaviourally vulnerable of the vector taxa that constituted the original transmission system. Mosquito taxa which have always exhibited such evasive traits may be more accurately described as behaviourally resilient, rather than resistant. Ongoing national or regional entomological monitoring surveys of physiological susceptibility to insecticides should be supplemented with biologically and epidemiologically meaningfully estimates of malaria vector population dynamics and the behavioural phenotypes that determine intervention impact, in order to design, select, evaluate and optimize the implementation of vector control measures

Genomic reconstruction of the SARS-CoV-2 epidemic in England.

The evolution of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus leads to new variants that warrant timely epidemiological characterization. Here we use the dense genomic surveillance data generated by the COVID-19 Genomics UK Consortium to reconstruct the dynamics of 71 different lineages in each of 315 English local authorities between September 2020 and June 2021. This analysis reveals a series of subepidemics that peaked in early autumn 2020, followed by a jump in transmissibility of the B.1.1.7/Alpha lineage. The Alpha variant grew when other lineages declined during the second national lockdown and regionally tiered restrictions between November and December 2020. A third more stringent national lockdown suppressed the Alpha variant and eliminated nearly all other lineages in early 2021. Yet a series of variants (most of which contained the spike E484K mutation) defied these trends and persisted at moderately increasing proportions. However, by accounting for sustained introductions, we found that the transmissibility of these variants is unlikely to have exceeded the transmissibility of the Alpha variant. Finally, B.1.617.2/Delta was repeatedly introduced in England and grew rapidly in early summer 2021, constituting approximately 98% of sampled SARS-CoV-2 genomes on 26 June 2021

The use of resuscitative endovascular balloon occlusion of the aorta to control hemorrhagic shock during video-assisted retroperitoneal debridement or infected necrotizing pancreatitis.

Introduction: Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a technique that has been shown to provide central vascular control to support proximal aortic pressure and minimize hemorrhage in a wide variety of clinic settings, however the role of REBOA for emergency general surgery is less defined. Case description: This is a report of a 44 year old man who experienced hemorrhagic shock during video-assisted retroperitoneal debridement (VARD) for necrotizing pancreatitis where REBOA was used to prevent ongoing hemorrhage and death. Discussion: This is the first documented report REBOA being used during pancreatic debridement in the literature and one of the first times it has been used in emergency general surgery. The use of REBOA is an option for those in hemorrhagic shock whom conventional aortic cross-clamping or supra-celiac aortic exposure is either not possible or exceedingly dangerous. Conclusion: REBOA allows for adequate resuscitation and can be used as a bridge to definitive therapy in a range of surgical subspecialties with minimal morbidity and complications. The risks associated with insertion of wires, sheaths, and catheters into the arterial system, as well as the risk of visceral and spinal cord ischemia due to aortic occlusion mandate that the use of this technique be utilized in only appropriate clinical scenarios

Seroepidemiological and parasitological evaluation of the heterogeneity of malaria infection in the Gambia.

BACKGROUND: As countries make progress in malaria control, transmission may be reduced to such an extent that few cases occur, and identification of the remaining foci of transmission may require a combination of surveillance tools. The study explored the usefulness of parasite prevalence, seroprevalence and model-estimated seroconversion rates for detecting local differences in malaria transmission in a West African country. METHODS: Age-stratified cross-sectional surveys were conducted during the wet season in 2008 and the following dry season in 2009 in The Gambia. In each season, 20 village communities were sampled from six diverse areas throughout the country. A total of 7,586 participants were surveyed, 51% (3,870) during the wet season. Parasites were detected by thick film slide microscopy, and anti-MSP1-19 antibodies were detected by ELISA using eluted dried blood from filter papers. RESULTS: Overall parasite prevalence was 12.4% in the wet season and 2.2% in the dry season, with village-specific parasite prevalence ranging from 1.4 to 45.9% in the wet season and from 0.0 to 13.2% in the dry season. Prevalence was highest in the eastern part of the country. Serological indices also varied between villages, indicating local heterogeneity in transmission, and there was a high correlation between wet and dry season estimates across the villages. The overall prevalence of anti-MSP119 antibodies was similar in the wet (19.5%) and in the dry (19.6%) seasons. CONCLUSION: The study illustrates the utility of measuring both parasite prevalence and serological indices for monitoring local variation in malaria transmission, which are more informative than single measures as control intensifies and malaria declines. Measurements of seropositivity have the logistical advantage of being relative stable seasonally so that sampling at any time of year may be conducted

Fetal adnexa-derived stem cells application in Horse model of tendon disease

The equine superficial digital flexor tendon is a frequently injured structure that is functionally and clinically equivalent to the human Achilles tendon. Both act as critical energy-storage systems during high-speed locomotion and can accumulate exercise- and age-related microdamage that predisposes to rupture during normal activity. The biology of tendon and its matrix, and the pathological changes occurring in the context of early injury in both horses and people are reviewed. In addition, this review focuses on the current use of stem cells (MSCs), recovered from either bone marrow or adipose tissue to treat strain-induced tendon injury in the horse with particular interest to non-embryonic extra-fetal-derived stem cells that open new perspectives for developmental biology and for regenerative medicine