Tiwary Puja, Singh Shakti Kumar, Kushwaha Anurag Kumar, Rowton Edgar, Sacks David, Singh Om Prakash, Sundar Shyam, Lawyer Phillip
Department of Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India.
Kala Azar Medical Research Center, Muzaffarpur, Bihar, India.
J Med Entomol. 2017 Sep 1;54(5):1129-1139. doi: 10.1093/jme/tjx099.
This pilot project was preliminary and essential to a larger effort to define the ability of certain human-subject groups across the infection spectrum to serve as reservoirs of Leishmania donovani infection to sand flies in areas of anthroponotic transmission such as in Bihar state, India. This is possible only via xenodiagnosis of well-defined subject groups using live vector sand flies. The objective was to establish at the Kala Azar Medical Research Center (KAMRC), Muzaffarpur, Bihar, India, a self-sustaining colony of Phlebotomus argentipes (Annandale & Brunneti), closed to infusion with wild-caught material and certified safe for human xenodiagnosis. Prior to this endeavor, no laboratory colony of this vector existed in India meeting the stringent biosafety requirements of this human-use study. From March through mid-December, 2015, over 68,000 sand flies were collected in human dwellings and cattle sheds using CDC-type light traps over 254 nights. Blood-fed and gravid P. argentipes females were selected and placed individually in isoline-rearing vials for oviposition, and >2,500 egg clutches were harvested. Progeny were reared according to standard methods, providing a continuous critical mass of F1 males and females to stimulate social feeding behavior. With construction of a large feeding cage and use of a custom-made rabbit restrainer, the desired level of blood-feeding on restrained rabbits was achieved to make the colony self-sustaining and expand it to working level. Once self-sustaining, the colony was closed to infusion with wild-caught material and certified free of specific human pathogens.
这个试点项目是初步的,但对于一项更大的工作至关重要,该工作旨在确定在印度比哈尔邦等人畜共患传播地区,处于感染谱不同阶段的某些人类受试者群体作为杜氏利什曼原虫感染白蛉宿主的能力。这只有通过使用活的媒介白蛉对明确界定的受试者群体进行异种诊断才能实现。目标是在印度比哈尔邦穆扎法尔布尔的黑热病医学研究中心(KAMRC)建立一个自给自足的银足白蛉(Annandale & Brunneti)种群,不引入野生捕获的材料,并经认证对人类异种诊断安全。在此之前,印度不存在符合这项人体使用研究严格生物安全要求的该媒介实验室种群。2015年3月至12月中旬,在254个夜晚使用疾控中心型诱虫灯在人类住所和牛棚中收集了超过68000只白蛉。挑选出吸食血液和怀孕的银足白蛉雌性个体,分别放入同系饲养小瓶中产卵,收获了超过2500个卵块。按照标准方法饲养后代,提供持续的关键数量的F1代雄性和雌性个体以刺激群体取食行为。通过建造一个大型饲养笼并使用定制的兔子束缚器,实现了在束缚兔子身上达到所需的取食水平,使种群能够自给自足并扩大到工作规模。一旦实现自给自足,该种群不再引入野生捕获的材料,并经认证无特定人类病原体。