Chronic infections of Haplosporidium nelsoni (MSX) in the oyster Crassostrea virginica
Chronic infections of Haplosporidium nelsoni (MSX) in the oyster Crassostrea virginica
复制标题
维吉尼亚牡蛎中纳尔逊单孢子虫 (MSX) 的慢性感染
DOI：
10.1016/0022-2011(85)90054-0
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发表时间：
1985
影响因子：
3.4
通讯作者：
S. Ford
中科院分区：
文献类型：
--
作者：
S. Ford
生活在纳尔逊单孢子虫(MSX)地方性疫区的牡蛎每年夏天都会暴露在感染颗粒中，通常很难区分新感染的病变和旧的感染。为了研究没有新感染并发症的长期寄生，感染MSX的牡蛎被从特拉华湾转移到新泽西海岸的一个没有疾病的地区。因为转移后的感染是在特拉华湾已知的感染期内获得的，所以有可能确定牡蛎感染的时间有多长，以及它们是如何受到慢性寄生虫的影响的。慢性感染表现出与每年再次感染的地方病地区相同的季节性周期(冬季和晚春高水平，夏季和早春低水平)。在个别牡蛎体内，慢性MSX变得局部化，复发为全身感染，然后又以可能受温度控制的顺序再次局部化。一些实验牡蛎在MSX的作用下存活了至少4年。血细胞增多症在这些牡蛎中持续存在，它们糟糕的状况表明，长期感染的人可能会降低对额外压力的抵抗力。
Oysters inhabiting areas enzootic for the parasiteHaplosporidium nelsoni(MSX) are exposed to infective particles each summer, and it is often difficult to distinguish newly acquired lesions from older infections. To study long-term parasitism without the complication of new infections, MSX-infected oysters were moved from Delaware Bay to a disease-free area on the New Jersey coast. Because infections seen after the transfer were acquired in Delaware Bay during a known infective period, it was possible to determine how long oysters remained infected and how they were affected by chronic parasitism. Chronic infections displayed the same seasonal cycle (high levels in winter and late spring, low levels in summer and early spring) that occurs in enzootic areas with annual reinfection. Within individual oysters, chronic MSX became localized, relapsed into general infections, and then became localized again in a sequence that was probably controlled by temperature. Some experimental oysters survived with MSX for at least 4 years. Hemocytosis persisted in these oysters, and their poor condition suggested that chronically infected individuals would have lowered resistance to additional stress.