da Costa-Val Adriane Pimenta, Cavalcanti Reginaldo Roris, de Figueiredo Gontijo Nelder, Michalick Marilene Suzan Marques, Alexander Bruce, Williams Paul, Melo Maria Norma
Escola de Veterinária da Universidade Federal de Minas Gerais, Departamento de Clínica e Cirurgia Veterinárias, Av. Antônio Carlos, 6627, P.O. Box 567, 30161-970 Belo Horizonte MG, Brazil.
Vet J. 2007 Nov;174(3):636-43. doi: 10.1016/j.tvjl.2006.11.006. Epub 2007 Jan 16.
The main source of Leishmania infantum infection in humans is a naturally infected dog. This study reports on the infectivity to phlebotomine sandflies (Lutzomyia longipalpis) of serologically positive mongrel dogs that differed in clinical status, haematology and humoral responses to immunoglobulin (Ig) G(T) (total anti-Leishmania IgG), IgG(1) and IgG(2) subclasses of antibody to crude antigen of L. infantum. Forty-five female L. longipalpis were allowed to feed directly on the ears of dogs classified as asymptomatic, oligosymptomatic or symptomatic before being dissected five days later. Promastigotes were detected in 88% of the dissected sandflies. The highest rate of infectivity to sandflies was found in symptomatic dogs, followed by oligosymptomatic and asymptomatic animals. The results suggest that dogs naturally infected with L. infantum with higher total IgG and IgG(2) concentrations and lower haematocrit levels were able to infect the highest proportion of L. longipalpis. No correlation was observed between anaemia and the intensity of clinical signs. Symptomatic dogs presented the highest infection rate and intensity of infection.
人类利什曼原虫婴儿亚种感染的主要来源是自然感染的狗。本研究报告了血清学阳性的杂种狗对白蛉（长须罗蛉）的感染性，这些狗在临床状态、血液学以及对婴儿利什曼原虫粗抗原的免疫球蛋白（Ig）G(T)（总抗利什曼原虫IgG）、IgG(1)和IgG(2)亚类抗体的体液反应方面存在差异。45只雌性长须罗蛉直接叮咬被分类为无症状、轻度症状或有症状的狗的耳朵，5天后解剖这些白蛉。在88%的解剖白蛉中检测到前鞭毛体。对白蛉感染率最高的是有症状的狗，其次是轻度症状和无症状的动物。结果表明，总IgG和IgG(2)浓度较高且血细胞比容水平较低的自然感染婴儿利什曼原虫的狗能够感染最高比例的长须罗蛉。未观察到贫血与临床症状强度之间的相关性。有症状的狗呈现出最高的感染率和感染强度。
