Photo Credit USDA
# 6740
From Hong Kong’s Centre for Health Protection today a report on five workers at an agricultural station who have contracted an – as yet unidentified – respiratory illness.
These patients have tested negative for the `usual suspects’, including influenza, RSV, and Legionnaire’s Disease. They all work at an animal management center that recently took in 16 seized parrots, 3 of which subsequently died.
Testing is now underway for Psittacosis (parrot fever). First the report, then I’ll return with a few brief notes.
Joint investigation into suspected outbreak of respiratory disease in Sheung Shui
The Centre for Health Protection (CHP) of the Department of Health is today (November 26) conducting a joint investigation with the Agriculture, Fisheries and Conservation Department (AFCD) into a suspected outbreak of respiratory disease involving five AFCD staff working in the New Territories North Animal Management Centre (NTNAMC) in Sheung Shui. They were all males aged between 27 and 64 with onset of symptoms from November 6 to November 24.
The first case affected a 64-year-old man who presented with upper respiratory symptoms since November 6. He was admitted to a hospital in Australia since November 12.
The second case is a 55-year-old man. He developed chills, cough and sore throat since November 8 and fever, shortness of breath, headache and myalgia since November 19. He was admitted to Queen Mary Hospital (QMH) on November 22. His chest X-ray showed bilateral upper zone patchiness and the clinical diagnosis was pneumonia. He is now receiving care in the Intensive Care Unit of QMH in stable condition.
Respiratory and urine specimens taken from the 55-year-old patient at QMH tested by the hospital yielded negative results for influenza virus, respiratory syncytial virus (RSV) and Legionnaires' Disease, while test results for psittacosis and leptospirosis are pending. CHP's Public Health Laboratory Centre performed tests on the patient's respiratory specimens and it was negative for Novel Coronavirus associated with Severe Respiratory Disease.
The third case affected a 62-year-old man who developed bilateral red eyes on November 12, and was admitted to Alice Ho Miu Ling Nethersole Hospital on November 17 because of cough with blood-stained sputum, malaise, chills, rigors and sore throat. His condition was stable. The diagnosis was pneumonia. Preliminary laboratory testing for influenza virus, parainfluenza virus, RSV and adenovirus was negative.
The fourth case is a 27-year-old man. He developed fever, headache and malaise on November 14 and was admitted to Yan Chai Hospital on November 18. The diagnosis was pneumonia. He recovered after treatment and was discharged home on November 22 and his condition was stable.
The fifth case affected a 62-year old man who presented with cough, chills and rigor since November 24 and was admitted to Princess Margaret Hospital for further management on November 26. His condition is stable.
The home contacts of the patients are asymptomatic.
CHP staff conducted a site visit to NTNAMC today and provided health advice to the staff.
According to the information provided by AFCD, there is a batch of 16 seized parrots being kept in NTNAMC since October 20. Subsequently, three died and 10 were euthanised as precautionary measures. The health condition of the three surviving birds is being closely monitored.
The possibility of psittacosis outbreak among these staff is being actively investigated.
While we don’t yet know if Psittacosis is behind this outbreak, parrot fever continues to cause small outbreaks around the world. It is caused by Chlamydia psittaci, one of several microorganisms in the genus Chlamydia that is shed in the feces of many birds.
In 2007 (see To You, My Heart Cries Out Chlamydia) I wrote about a small outbreak that occurred at a Bird lovers Society show in Weurt, Norway.
And earlier this year I told the fascinating story of how parrot fever was responsible for the creation of the NIH in the United States (see How Parrot Fever Changed Public Health In America).
The CDC maintains a Psittacosis website, with the following information.
Clinical Features
In humans, fever, chills, headache, muscle aches, and a dry cough. Pneumonia is often evident on chest x-ray.Etiologic Agent
Chlamydia psittaci, a bacteriumIncidence
Since 1996, fewer than 50 confirmed cases were reported in the United States each year. Many more cases may occur that are not correctly diagnosed or reported.Sequelae
Endocarditis, hepatitis, and neurologic complications may occasionally occur. Severe pneumonia requiring intensive-care support may also occur. Fatal cases have been reported.Transmission
Infection is acquired by inhaling dried secretions from infected birds. The incubation period is 5 to 19 days. Although all birds are susceptible, pet birds (parrots, parakeets, macaws, and cockatiels) and poultry (turkeys and ducks) are most frequently involved in transmission to humans.Risk Groups
Bird owners, pet shop employees, and veterinarians. Outbreaks of psittacosis in poultry processing plants have been reported.Surveillance
Psittacosis is a reportable condition in most states.Trends
Annual incidence varies considerably because of periodic outbreaks. A decline in reported cases since 1988 may be the result of improved diagnostic tests that distinguish C.psittaci from more common C. pneumoniae infections.Challenges
Diagnosis of psittacosis can be difficult. Antibiotic treatment may prevent an antibody response, thus limiting diagnosis by serologic methods. Infected birds are often asymptomatic. Tracebacks of infected birds to distributors and breeders often is not possible because of limited regulation of the pet bird industry.Opportunities
Characterize new and rapid diagnostic tests for human and avian psittacosis, and determine value of screening flocks for avian psittacosis to prevent human infection.
