Clinical features of endemic community-acquired psittacosis

Abstract

Following a large outbreak of community-acquired psittacosis in 2002 in residents of the Blue Mountains, New South Wales, Australia, we reviewed new cases in this area over a 7-year period from 2003 to 2009. Using the 2010 criteria from the Centers for Disease Control National Notifiable Diseases Surveillance System, 85 patients with possible psittacosis were identified, of which 48 were identified as definite or probable infection. Clinical features of these cases are summarized. In addition to Chlamydia -specific serology, specimens, where available, underwent nucleic acid testing for chlamydial DNA using real-time PCR. Chlamydophila psittaci DNA was detected in samples from 23 patients. Four of 18 specimens were culture positive. This is the first description of endemic psittacosis, and is characterized in this location by community-acquired psittacosis resulting from inadvertent exposure to birds. The disease is likely to be under-diagnosed, and may often be mistaken for gastroenteritis or meningitis given the frequency of non-respiratory symptoms, particularly without a history of contact with birds. Clinical characteristics of endemic and outbreak-associated cases were similar. The nature of exposure, risk factors and reasons for the occurrence of outbreaks of psittacosis require further investigation.

An outbreak of psittacosis at a veterinary school demonstrating a novel source of infection

“…The study was unable to identify any association between psittacosis and bird contact [32]. Similar results were found in an Australian study in which 29 cases (60%) did not have direct bird contact [17]. Further research using qPCR technology is required to characterise the prevalence of C. psittaci disease attributable to equine and other non-avian sources.…”

Recent history of psittacosis in Australia: expanding our understanding of the epidemiology of this important globally distributed zoonotic disease

“…It is likely that human infections are underdiagnosed as: (i) most cases of community acquired pneumonia receive treatment without testing; 16 (ii) infections are misdiagnosed; 17 and/or (iii) specific molecular testing for C. psittaci and other chlamydial species, based on clinical features and risk factors alone, may mean that infections are missed. It is likely that human infections are underdiagnosed as: (i) most cases of community acquired pneumonia receive treatment without testing; 16 (ii) infections are misdiagnosed; 17 and/or (iii) specific molecular testing for C. psittaci and other chlamydial species, based on clinical features and risk factors alone, may mean that infections are missed.…”

“…As in the rest of the world, psittacosis in Australia is still considered to be a rare but important cause of zoonotic disease. It is likely that human infections are underdiagnosed as: (i) most cases of community acquired pneumonia receive treatment without testing; 16 (ii) infections are misdiagnosed; 17 and/or (iii) specific molecular testing for C. psittaci and other chlamydial species, based on clinical features and risk factors alone, may mean that infections are missed. 18 While C. psittaci zoonoses resulting from direct contact with birds should still be considered the most important risk factor for psittacosis in humans, the results of recent Australian studies reveal that primary care physicians and public health authorities need to consider carefully alternative transmission routes for this zoonotic agent in patients with suspected pneumonia of unknown origin.…”

Psitacose: A Propósito de Um Caso Clínico

“…Estas podem ser portadoras assintomáticas ou manifestar doença. 9,12 No período sintomático, eliminam um elevado inóculo bacteriano.…”