Viral infections in children undergoing hematopoietic stem cell transplant

Background Although viral infection is a major clinical problem for hematopoietic stem cell transplant recipients, there are few large series reporting on these infections in the pediatric population. We performed a retrospective analysis of the impact of viral infections in this patient population in our center, managed by a uniform antiviral prophylaxis protocol. Method We reviewed the medical records of consecutive children and adolescents who received hematopoietic stem cell transplantation at the Division of Pediatrics, The University of Texas M. D. Anderson Cancer Center in Houston, TX, from July, 1992 to August, 1996. Results. During the study period there were 70 episodes of viral infections in 96 transplants. The viruses most commonly encountered were cytomegalovirus (24), varicella-zoster (21) and herpes simplex (10). Fifty of these episodes resulted in clinically apparent diseases, affecting 39 patients. The Kaplan-Meier estimated probability for the development of viral diseases was 62%. Ten percent of these patients died as a direct result of the infectious process, all within 4 months of transplant. Significant factors for development of viral disease were the development of acute graft-vs. -host disease and the duration of preengraftment neutropenia. Conclusions. Viruses are common pathogens after hematopoietic stem cell transplantation in the pediatric population. Despite routine antiviral prophylaxis the morbidity and mortality of viral infections remain high. Enhancement of immune recovery after hematopoietic stem cell transplantation together with the development of new classes of antiviral agents may impact the incidence and prognosis of viral infections in this setting

Census and distribution of large carnivores in the Tsavo national parks, a critical east African wildlife corridor

Kenya's Tsavo National Parks are a critical conservation area and the only wilderness corridor through densely populated human-dominated landscapes stretching from the East African coast to Lake Victoria, separating extensive undeveloped grasslands south of the equator from the undeveloped semiarid bushlands to the north. At nearly 21,000 km(2), Tsavo is one of four lion strongholds in East Africa and part of Africa's most important populations of all other large African carnivores. To provide baseline data on the status of large carnivores, a track survey was undertaken in 2013. Lions and both hyaena species were widely distributed across both parks, while cheetahs and wild dogs were more patchily distributed. Spotted hyaenas were the most abundant, with an estimated population of 3,903 +/- 514 (95% CI), followed by lion (706 +/- 201), striped hyaena (679 +/- 144), leopard (452 +/- 98), cheetah (154 +/- 74) and wild dog (111 +/- 92). Tsavo's carnivores suffer from bushmeat poaching, illegal grazing and retaliatory killing, and increasing human numbers on its periphery. Given Tsavo's importance as a stronghold for lions and an ecological corridor, increased investment in effective protection is strongly recommended. Evaluating trends will require complementary techniques in light of intensive monitoring requirements