Department of Bacteriology, Host-Pathogen Interaction and Diagnostics Development, Wageningen Bioveterinary Research, Lelystad, The Netherlands.
Department of Diagnostics and Crisis Organisation, Wageningen Bioveterinary Research, Lelystad, The Netherlands.
Vet Res. 2021 Nov 20;52(1):141. doi: 10.1186/s13567-021-01011-y.
Chlamydia psittaci was considered the predominant chlamydial species in poultry until Chlamydia gallinacea was discovered in 2009. C. psittaci is a zoonotic obligate intracellular bacterium reported in more than 465 bird species including poultry. In poultry, infections can result in asymptomatic disease, but also in more severe systemic illness. The zoonotic potential of C. gallinacea has yet to be proven. Infections in poultry appear to be asymptomatic and in recent prevalence studies C. gallinacea was the main chlamydial species found in chickens. The high prevalence of C. gallinacea resulted in the question if an infection with C. gallinacea might protect against an infection with C. psittaci. To investigate possible cross protection, chickens were inoculated with C. gallinacea NL_G47 and subsequently inoculated with either a different strain of C. gallinacea (NL_F725) or C. psittaci. Chickens that had not been pre-inoculated with C. gallinacea NL_G47 were used as a C. gallinacea or C. psittaci infection control. In the groups that were inoculated with C. psittaci, no difference in pharyngeal or cloacal shedding, or in tissue dissemination was observed between the control group and the pre-inoculated group. In the groups inoculated with C. gallinacea NL_F725, shedding in cloacal swabs and tissues dissemination was lower in the group pre-inoculated with C. gallinacea NL_G47. These results indicate previous exposure to C. gallinacea does not protect against an infection with C. psittaci, but might protect against a new infection of C. gallinacea.
鹦鹉热衣原体曾被认为是禽类中的主要衣原体种，直到 2009 年发现了鸡衣原体。鹦鹉热衣原体是一种严格的细胞内需氧菌，已在 465 种以上鸟类中发现，包括家禽。在家禽中，感染可导致无症状疾病，但也可导致更严重的全身性疾病。鸡衣原体的人畜共患潜力尚未得到证实。家禽感染似乎无症状，在最近的流行率研究中，鸡衣原体是在鸡中发现的主要衣原体种。鸡衣原体的高流行率导致了一个问题，即感染鸡衣原体是否可以预防感染鹦鹉热衣原体。为了研究可能的交叉保护作用，鸡用鸡衣原体 NL_G47 进行了接种，随后用不同的鸡衣原体（NL_F725）或鹦鹉热衣原体进行了接种。未用鸡衣原体 NL_G47 进行预接种的鸡被用作鸡衣原体或鹦鹉热衣原体感染的对照组。在接种了鹦鹉热衣原体的组中，在咽或泄殖腔拭子中脱落，或组织传播方面，对照组和预接种组之间没有差异。在接种了鸡衣原体 NL_F725 的组中，在预接种了鸡衣原体 NL_G47 的组中，在泄殖腔拭子和组织传播中的脱落率较低。这些结果表明，先前暴露于鸡衣原体并不能预防感染鹦鹉热衣原体，但可能预防新的鸡衣原体感染。
