Isolation and typing of Cryptococcus neoformans in fecal specimens from pigeon and other birds in Taiwan

• Main Authors: Chih-feng Chen, 陳志峯
• Other Authors: Ming-jeng Pan
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/21170259972148802633

碩士 === 中臺科技大學 === 醫學生物科技研究所 === 99 === Cryptococcosis, a zoonotic disease, can cause fatal meningoencephalitis in humans or patients who have acquired immune deficiency syndrome (AIDS), with cancer, with organ transplantation and with defective immunity. Cryptococcus neoformans, a wide spread opportunistic pathogen of cryptococcosis, can be isolated from Eucalyptus trees, soil and the bird droppings especially pigeons. There are three varieties of this organism: C. neoformans var. grubii (serotype A), C. neoformans var. neoformans (serotype D) and C. neoformans var. gattii (serotype B and C). According to the specific immunologic properties of their capsular polysaccharide, they have been divided into five distinct serotypes (A, B, C, D and AD). Based on the previous studies, pigeon droppings were the important reservoir of C. neoformans var. grubii and C. neoformans var. neoformans. To understand the distribution of C. neoformans in pigeons and other birds, we collected fecal specimens from all over Taiwan during April to November, 2009. A total of 1,178 fresh fecal specimens from pigeons and other birds were collected from the whole Taiwan including Kinmen and Penghu off-shore islands. The results showed the isolation rate were 6.62% (74/1,118) and 5.0% (3 / 60) in pigeons and the other birds’ feces respectively, without significant differences. In this investigation, the total positive rate was 6.54% (77/1178), the positive rate in northern Taiwan was 12.8% (47/368), and central Taiwan positive rate was 6.0% (25/416), 1.9% positive rate in southern Taiwan (4 / 216) and off-shore islands positive rate was 1.3% (1 / 75). The survey found that all 77 isolates belonged to serotype A and VNI molecular type, which are similar to domestic human isolates reported. Their correlation deserves public health attention.