最新研究结论：

　蝙蝠中也不存在狂犬病毒的隐性感染，

　感染狂犬病毒后不发病的蝙蝠无传染性。

美国科罗拉多州立大学、美国CDC等单位的研究人员今年在PLoS ONE上发表研究论文，阐述狂犬病毒中和抗体（RVNA）在蝙蝠血清中的存在不应被解释为持续感染狂犬病毒的证据，即目前尚无蝙蝠持续感染狂犬病毒的证据。在血清学阳性蝙蝠的口咽分泌物和安乐死的血清学阳性蝙蝠的所有器官中，均未发现狂犬病毒RNA，即这些蝙蝠都不具有感染性。

以前曾发表过大量有关于野生动物狂犬病感染的血清流行病学研究，发现个别食肉目动物和人在未接种疫苗的情况下仍可检测到低水平RVNA。这些动物和人都未发病，同时其体内任何时候也检测不到狂犬病毒或病毒RNA。可推测这些动物也不存在狂犬病的持续感染，它们不传播狂犬病，对狂犬病的流行不起作用。

论文题目：

Variability in Seroprevalence of Rabies Virus Neutralizing Antibodies and Associated Factors in a Colorado Population of Big Brown Bats (Eptesicus fuscus).

科罗拉多州大棕蝠(Eptesicus fuscus)群体中狂犬病毒中和抗体的血清流行病学变化及影响因素。

作者：

ThomasJ. O’Shea1*, Richard A. Bowen2,  ThomasR. Stanley1,  Vidya Shankar 2,3¤ ,Charles E. Rupprecht4,5

作者单位：

1  United States Geological Survey, Fort Collins Science Center, Fort Collins,Colorado, United States of America,

2  Department of Biomedical Sciences, Colorado State University, Fort Collins,Colorado, United States of America,

3  Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America,

4  Ross University School of Veterinary Medicine, Basseterre, Saint Kitts, West Indies,

5  The Global Alliance for Rabies Control, Manhattan, Kansas, United States of America

发表的杂志：

PLoS ONE 9(1): e86261. doi:10.1371/journal.pone.0086261

摘要

科罗拉多州柯林斯堡（Fort Collins）的建筑物是大棕蝠(Eptesicus fuscus)的夏季栖息地之一。在2001-2005年，我们在该地采集具有永久性标记的大棕蝠标本，检测狂犬病毒中和抗体（RVNA）。成年雌性的血清学阳性率（17.9％，N =2,332）明显高于雄性（9.4％，N =128，P=0.007），也高于会飞的幼年大棕蝠（10.2％，N =738，P =0.0001）。血清阳性率在大量使用杀虫剂的大旱之年最低，而在其他正常年份则较高，这表明环境压力可能会抑制大棕蝠中RVNA的产生。在5年期间在成年雌性的5个栖息地每年抽样，血清阳性率也随蝙蝠年龄的增长而增加，变化幅度是从6.2%直到26.7％。在其他17个栖息地采集成年雌性的样品，1～4年间血清阳性率的变化介于0%至47.1％之间。

对我们采集的样品的血清学状况变化采用对数回归方法建立排序模型，表明是随不同年份和季节的相对干旱状况的变化而变化。个别蝙蝠的抗体存在与否随时间而变化。成年雌性蝙蝠从先前血清学阳性状态转变成阴性状态，用年度模式可能提供最佳解释。解释由血清学阴性转变为阳性的唯一有竞争力的模型是季节的天数，随着季节的推进阳转率会增加。在261只血清学阳性蝙蝠的口咽分泌物和13只安乐死的血清学阳性蝙蝠的器官中，我们均未发现狂犬病毒RNA。血清学阳性和阴性的蝙蝠的存活率没有显着差异。 RVNA在蝙蝠血清中的存在不应被解释为持续感染狂犬病的证据。

Abstract

In 2001–2005 we sampled permanently marked big brown bats (Eptesicus fuscus) at summer roosts in buildings at Fort Collins, Colorado, for rabies virus neutralizing antibodies (RVNA). Seroprevalence was higher in adult females(17.9%, n = 2,332) than males (9.4%, n = 128; P = 0.007) or volant juveniles(10.2%, n = 738; P,0.0001). Seroprevalence was lowest in a drought year with local insecticide use and highest in the year with normal conditions,suggesting that environmental stress may suppress RVNA production in big brown bats. Seroprevalence also increased with age of bat, and varied from 6.2 to 26.7% among adult females at five roosts sampled each year for five years.Seroprevalence of adult females at 17 other roosts sampled for 1 to 4 years ranged from 0.0 to 47.1%.

Using logistic regression, the only ranking model in our candidate set of explanatory variables for serological status at first sampling included year, day of season, and a year by day of season interaction that varied with relative drought conditions. The presence or absence of antibodies in individual bats showed temporal variability. Year alone provided the best model to explain the likelihood of adult female bats showing a transition to seronegative from a previously seropositive state. Day of the season was the only competitive model to explain the likelihood of a transition from seronegative to seropositive,which increased as the season progressed. We found no rabies viral RNA in oropharyngeal secretions of 261 seropositive bats or in organs of 13 euthanized seropositive bats. Survival of seropositive and seronegative bats did not differ. The presence of RVNA in serum of bats should not be interpreted as evidence for ongoing rabies infection.

PDF全文下载： RVNA in Big Brown Bats-pone-2014.pdf

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