Phalen D N, Radabaugh C S, Dahlhausen R D, Styles D K
Department of Large Animal Medicine and Surgery, College of Veterinary Medicine, Texas A&M University, College Station 77843, USA.
J Am Vet Med Assoc. 2000 Jul 1;217(1):32-6. doi: 10.2460/javma.2000.217.32.
To determine rapidity of spread and onset and duration of viremia, virus shedding, and antibody production in parrots naturally infected with avian polyomavirus (APV).
Case series.
92 parrots in 2 aviaries.
Blood samples were obtained from parrots naturally exposed to APV during a 3- to 4-month period for determination of serum virus neutralizing antibody and detection of viral DNA. Nestlings from the next year's hatch were monitored for APV infection.
The first indication of inapparent infection was viremia, which developed simultaneously with or was followed within 1 week by cloacal virus shedding and antibody production. Cloacal virus shedding continued after viremia ceased. During viremia, viral DNA was detected continuously in blood samples. Viral DNA was detected in serial cloacal swab specimens in most birds, but it was detected inconsistently in 6 birds and not detected in 3 birds, even though these birds were viremic. Duration of cloacal virus shedding was < or = 4.5 months. In 1 aviary, prevalence of infection was 88% and dissemination of virus through the 3-room building required 4.5 months. In the second aviary, a single-room nursery, prevalence of infection was > or = 90%. For all affected birds, infection could be detected 18 days after the first death.
If a single sampling is used for polymerase chain reaction detection of viral DNA, blood and cloacal swab specimens are required. In nestling nonbudgerigar parrots, cloacal virus shedding may persist for 4.5 months. Management protocols alone are sufficient to prevent introduction of APV into a nursery.
确定自然感染禽多瘤病毒（APV）的鹦鹉体内病毒血症的传播速度、发病时间、持续时间、病毒排出情况及抗体产生情况。
病例系列研究。
两个鸟舍中的92只鹦鹉。
在3至4个月期间，从自然接触APV的鹦鹉身上采集血样，以测定血清病毒中和抗体并检测病毒DNA。对次年孵化的雏鸟进行APV感染监测。
隐性感染的首个迹象是病毒血症，其与泄殖腔病毒排出及抗体产生同时出现或在1周内相继出现。病毒血症停止后，泄殖腔仍持续排出病毒。病毒血症期间，血样中可连续检测到病毒DNA。多数鸟类的系列泄殖腔拭子标本中可检测到病毒DNA，但6只鸟检测结果不一致，3只鸟未检测到，即便这些鸟存在病毒血症。泄殖腔病毒排出持续时间≤4.5个月。在一个鸟舍中，感染率为88%，病毒在三室建筑内传播需4.5个月。在第二个鸟舍（单间育雏室）中，感染率≥90%。对于所有受感染鸟类，在首次死亡后18天可检测到感染。
若仅通过一次采样利用聚合酶链反应检测病毒DNA，则需要采集血液和泄殖腔拭子标本。在雏鸟非虎皮鹦鹉中，泄殖腔病毒排出可能持续4.5个月。仅靠管理方案足以防止APV传入育雏室。
