Urban ecology of the Vervet Monkey Chlorocebus pygerythrus in KwaZulu-Natal, South Africa.

Doctor of Philosophy in Biological Sciences. University of KwaZulu-Natal, Pietermaritzburg 2017The spread of development globally is extensively modifying habitats and often results in competition for space and resources between humans and wildlife. For the last few decades a central goal of urban ecology research has been to deepen our understanding of how wildlife communities respond to urbanisation. In the KwaZulu-Natal Province of South Africa, urban and rural transformation has reduced and fragmented natural foraging grounds for vervet monkeys Chlorocebus pygerythrus. However, no data on vervet urban landscape use exist. They are regarded as successful urban exploiters, yet little data have been obtained prior to support this. This research investigated aspects of the urban ecology of vervet monkeys in three municipalities of KwaZulu-Natal (KZN), as well as factors that may predict human-monkey conflict. Firstly, through conducting an urban wildlife survey, we were able to assess residents’ attitudes towards, observations of and conflict with vervet monkeys, investigating the potential drivers of intragroup variation in spatial ecology, and identifying predators of birds’ nests. We analysed 602 surveys submitted online and, using ordinal regression models, we ascertained that respondents’ attitudes towards vervets were most influenced by whether or not they had had aggressive interactions with them, by the belief that vervet monkeys pose a health risk and by the presence of bird nests, refuse bins and house raiding on their properties. Secondly, to investigate the vervet monkeys perceived negative impact on urban nesting birds, 75 artificial nests were deployed, and monitored by camera traps. Overall, 17 were depredated, 15 by monkeys and two by domestic cats Felis catus. It was determined that future experiments on natural nest predation are essential for comparison. Thirdly, by collecting observational data on 20 vervet monkey troops living in a variety of developed landscapes within KZN, it was found that the key landscape features influencing vervet monkey troop-level visitation rates, durations and observed foraging in residences were the absence of dogs, presence of supplementary food provisioning, fruiting trees, trees taller than two meters, and a high percentage of tree coverage. Data analysis revealed higher visitation rates during winter, in gardens with higher tree density, and the highest foraging rates in gardens closer to main roads, where supplementary provisioning and bird feeders were present. Furthermore, gardens with greater canopy cover had higher rates of feeding, grooming and playing, which all decreased with increasing troop size, while resting rates decreased with increasing distance from indigenous forest patches and main roads. Gardens experiencing comparatively low levels of visitation experienced high levels of raiding. The combination of these variables appears to provide monkeys with predictable, accessible, indigenous, exotic and anthropogenic food sources in human-modified habitats within close proximity to suitable sleeping sites and safety. Lastly, we examined vervet monkey space use using GPS/UHF telemetry data from 10 vervet monkeys across six troops over nine months within a 420 ha eco-estate. We documented a mean home range of 0.99 km2 (95% MCP) and 1.07 km2 (95% FK) for females (n = 6), 1 km2 (95% MCP) and 1.50 km2 (95% FK) for males (n = 4) and 0.87 km2 (95% MCP) and 1.12 km2 (95% FK) for troops (n=6), respectively, indicating that males and larger troops had larger home ranges. These relatively small home ranges included shared territorial boundaries and high home range overlap. Vervet monkey movements indicated higher morning activity levels and habitat selection indicated significantly more use of golf course, urban residential and forest, thicket and woodland areas, and avoidance of wetland, grassland and shrub, and urban built-up areas. Our results suggest that modified-habitat use by vervet monkeys is a consequence of behavioural facilitation to access highly-available food resources, thereby facilitating their persistence in developing ecosystems in South Africa. Therefore, conflict management is dependent on the conservation of sufficient natural habitats and food resources, to minimize their dependence on manmade resources and consequently reduce human-monkey conflict. The results contributed to an understanding of the drivers of urban vervet monkey spatial ecology within a transformed landscape. This hopefully will assist in determining the most sustainable way to mitigate conflict and manage vervet monkeys in these municipalities. In a broader context, this study highlights the value of citizen science and wildlife spatial ecology studies in providing mechanisms for identifying priority management and conservation efforts at the highly complex human-wildlife interface

VentBase: Developing a consensus among stakeholders in the deep-sea regarding environmental impact assessment for deep-sea mining – A workshop report

Mining seafloor massive sulfides for metals is an emergent industry faced with environmental management challenges. These revolve largely around limits to our current understanding of biological variability in marine systems, a challenge common to all marine environmental management. VentBase was established as a forum where academic, commercial, governmental, and non-governmental stakeholders can develop a consensus regarding the management of exploitative activities in the deep-sea. Participants advocate a precautionary approach with the incorporation of lessons learned from coastal studies. This workshop report from VentBase encourages the standardization of sampling methodologies for deep-sea environmental impact assessment. VentBase stresses the need for the collation of spatial data and importance of datasets amenable to robust statistical analyses. VentBase supports the identification of set-asides to prevent the local extirpation of vent-endemic communities and for the post-extraction recolonization of mine sites.<br/

Thigh-length compression stockings and DVT after stroke

Controversy exists as to whether neoadjuvant chemotherapy improves survival in patients with invasive bladder cancer, despite randomised controlled trials of more than 3000 patients. We undertook a systematic review and meta-analysis to assess the effect of such treatment on survival in patients with this disease

SARS-CoV-2 evolution during treatment of chronic infection

The spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is critical for virus infection through the engagement of the human ACE2 protein1 and is a major antibody target. Here we show that chronic infection with SARS-CoV-2 leads to viral evolution and reduced sensitivity to neutralizing antibodies in an immunosuppressed individual treated with convalescent plasma, by generating whole-genome ultra-deep sequences for 23 time points that span 101&nbsp;days and using in vitro techniques to characterize the mutations revealed by sequencing. There was little change in the overall structure of the viral population after two courses of remdesivir during the first 57&nbsp;days. However, after convalescent plasma therapy, we observed large, dynamic shifts in the viral population, with the emergence of a dominant viral strain that contained a substitution (D796H) in the S2 subunit and a deletion (ΔH69/ΔV70) in the S1 N-terminal domain of the spike protein. As passively transferred serum antibodies diminished, viruses with the escape genotype were reduced in frequency, before returning during a final, unsuccessful course of convalescent plasma treatment. In vitro, the spike double mutant bearing both ΔH69/ΔV70 and D796H conferred modestly decreased sensitivity to convalescent plasma, while maintaining infectivity levels that were similar to the wild-type virus.The spike substitution mutant D796H appeared to be the main contributor to the decreased susceptibility to neutralizing antibodies, but this mutation resulted in an infectivity defect. The spike deletion mutant ΔH69/ΔV70 had a twofold higher level of infectivity than wild-type SARS-CoV-2, possibly compensating for the reduced infectivity of the D796H mutation. These data reveal strong selection on SARS-CoV-2 during convalescent plasma therapy, which is associated with the emergence of viral variants that show evidence of reduced susceptibility to neutralizing antibodies in immunosuppressed individuals

Azithromycin in patients admitted to hospital with COVID-19 (RECOVERY): a randomised, controlled, open-label, platform trial

Background Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatory actions. We aimed to evaluate the safety and efficacy of azithromycin in patients admitted to hospital with COVID-19. Methods In this randomised, controlled, open-label, adaptive platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), several possible treatments were compared with usual care in patients admitted to hospital with COVID-19 in the UK. The trial is underway at 176 hospitals in the UK. Eligible and consenting patients were randomly allocated to either usual standard of care alone or usual standard of care plus azithromycin 500 mg once per day by mouth or intravenously for 10 days or until discharge (or allocation to one of the other RECOVERY treatment groups). Patients were assigned via web-based simple (unstratified) randomisation with allocation concealment and were twice as likely to be randomly assigned to usual care than to any of the active treatment groups. Participants and local study staff were not masked to the allocated treatment, but all others involved in the trial were masked to the outcome data during the trial. The primary outcome was 28-day all-cause mortality, assessed in the intention-to-treat population. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936. Findings Between April 7 and Nov 27, 2020, of 16 442 patients enrolled in the RECOVERY trial, 9433 (57%) were eligible and 7763 were included in the assessment of azithromycin. The mean age of these study participants was 65·3 years (SD 15·7) and approximately a third were women (2944 [38%] of 7763). 2582 patients were randomly allocated to receive azithromycin and 5181 patients were randomly allocated to usual care alone. Overall, 561 (22%) patients allocated to azithromycin and 1162 (22%) patients allocated to usual care died within 28 days (rate ratio 0·97, 95% CI 0·87–1·07; p=0·50). No significant difference was seen in duration of hospital stay (median 10 days [IQR 5 to >28] vs 11 days [5 to >28]) or the proportion of patients discharged from hospital alive within 28 days (rate ratio 1·04, 95% CI 0·98–1·10; p=0·19). Among those not on invasive mechanical ventilation at baseline, no significant difference was seen in the proportion meeting the composite endpoint of invasive mechanical ventilation or death (risk ratio 0·95, 95% CI 0·87–1·03; p=0·24). Interpretation In patients admitted to hospital with COVID-19, azithromycin did not improve survival or other prespecified clinical outcomes. Azithromycin use in patients admitted to hospital with COVID-19 should be restricted to patients in whom there is a clear antimicrobial indication. Funding UK Research and Innovation (Medical Research Council) and National Institute of Health Research