RESUMEN
Climate change-driven alterations in Arctic environments can influence habitat availability, species distributions and interactions, and the breeding, foraging, and health of marine mammals. Phocine distemper virus (PDV), which has caused extensive mortality in Atlantic seals, was confirmed in sea otters in the North Pacific Ocean in 2004, raising the question of whether reductions in sea ice could increase contact between Arctic and sub-Arctic marine mammals and lead to viral transmission across the Arctic Ocean. Using data on PDV exposure and infection and animal movement in sympatric seal, sea lion, and sea otter species sampled in the North Pacific Ocean from 2001-2016, we investigated the timing of PDV introduction, risk factors associated with PDV emergence, and patterns of transmission following introduction. We identified widespread exposure to and infection with PDV across the North Pacific Ocean beginning in 2003 with a second peak of PDV exposure and infection in 2009; viral transmission across sympatric marine mammal species; and association of PDV exposure and infection with reductions in Arctic sea ice extent. Peaks of PDV exposure and infection following 2003 may reflect additional viral introductions among the diverse marine mammals in the North Pacific Ocean linked to change in Arctic sea ice extent.
Asunto(s)
Organismos Acuáticos/virología , Cetáceos/virología , Virus del Moquillo Focino/metabolismo , Moquillo , Calentamiento Global , Hielo , Nutrias/virología , Animales , Regiones Árticas , Moquillo/epidemiología , Moquillo/transmisión , Virus del Moquillo Focino/patogenicidadRESUMEN
OBJECTIVE: To aims of this study was to assess and compare the efficacy of PTA and surgery in the treatment of severe lower limb ischaemia. DESIGN: Prospective 12-month study of 180 consecutive patients with severe chronic lower limb ischaemia. METHODS: PTA was used as first line therapy whenever possible and appropriate. Surgical revascularisation, primary amputation and conservative therapy were used in eh remaining patients. Patient survival and limb salvage were derived using life table analysis. RESULTS: Revascularisation was attempted in 135 (75%) patients, with PTA in 82 (46%), surgery in 19 (27%) and a combination of both in four (2%). Overall 12-month survival and limb salvage was 75% and 71%, respectively. Surgery and PTA had significantly higher survival rates (91% and 78%) than primary amputation or conservative therapy (57% and 52%) (p < 0.0001 log rank test). Revascularisation with either surgery or PTA achieved the same limb salvage rate of 76%. CONCLUSION: A large proportion of patients with severe chronic lower limb ischaemia can be managed by PTA. THis management strategy produces a clinically effective outcome at 1-year.