Yesterday's announcement of Hong Kong's second H7N9 case in just two weeks came with the suspicion - because of the reported onset date of the 26th - that the virus might have been acquired locally rather than from the patient's recent trip to Guangdong province.
Today's HK CHP update backs away from the 26th onset date slightly - based on the interpretation of chest x-rays - and makes it more likely this was an imported case.
The incubation period for H7N9 is thought to max out between 7 and 10 days, although outliers are always possible. With symptom onset based on the patient's subjective recall, a certain amount of `fudge factor' comes into play.
While potentially good news for Hong Kong, today's update does not (yet) declare this to be an `imported' case.
This latest Hong Kong case is just one of three cases announced yesterday, and so today's update also mentions the Hunan and Shanghai cases.
The Centre for Health Protection (CHP) of the Department of Health today (December 30) reported an update on the second human case of avian influenza A(H7N9) in Hong Kong this winter.
Enquiries revealed that the male patient aged 70 had claimed that he had come across mobile stalls selling live poultry in Shagang Xu, Zhongshan, on December 14.
Although the patient claimed to have symptoms on December 26, according to the clinical and chest radiological assessment, the onset of his illness was likely to be before December 26.
Contact tracing has so far identified 17 close contacts and 85 other contacts.
Close contacts include the patient's family contacts as well as relevant in-patients, visitors and healthcare workers (HCWs) of United Christian Hospital (UCH). All have remained asymptomatic. They will be given antiviral prophylaxis with oseltamivir (Tamiflu) for five days, advised to wear a mask and put under medical surveillance for 10 days following their last exposure to the patient.
Other contacts are the patient's travel collateral, other family members, relevant in-patients, visitors and HCWs of UCH. His travel collateral with cough tested negative for influenza A virus and the others have remained asymptomatic. They will be advised to wear a mask and will be put under medical surveillance for 10 days following their last exposure to the patient.
The CHP is also closely monitoring a total of two additional human cases of avian influenza A(H7N9) in Hunan and Shanghai, and again urged the public to maintain strict personal, food and environmental hygiene both locally and during travel.
According to the Hunan Provincial Center for Disease Control and Prevention, the female patient aged 53 from Shaoyang had close contact with poultry before onset. In addition, the Shanghai Municipal Commission of Health and Family Planning reported that the male patient aged 34 is from Sichuan.
"Locally, two human cases of avian influenza A(H7N9) were recently detected in this winter. Neighbouring Guangdong and Macau also reported their first human H7N9 cases in this winter. The activity of avian influenza is expected to increase in winter based on its seasonal pattern," a spokesman for the CHP said.
"The public should avoid touching birds, poultry or their droppings and visiting poultry markets or farms during travel, particularly in the upcoming New Year holidays. If feeling unwell such as having fever or cough, wear a mask and seek medical advice at once. Travellers returning from affected areas should consult doctors promptly if symptoms develop and let them know their travel history," the spokesman added.
The CHP's Port Health Office conducts health surveillance measures at all boundary control points. Thermal imaging systems are in place for body temperature checks on inbound travellers. Suspected cases will be immediately referred to public hospitals for follow-up.
The display of posters and broadcasting of health messages in departure and arrival halls as health education for travellers is under way. The travel industry and other stakeholders are regularly updated on the latest information.
The public should maintain strict personal, hand, food and environmental hygiene and take heed of the advice below while handling poultry:
The public may visit the CHP's pages for more information: the avian influenza page, the weekly Avian Influenza Report, global statistics and affected areas of avian influenza, the Facebook Page and the YouTube Channel.
- Avoid touching poultry, birds, animals or their droppings;
- When buying live chickens, do not touch them and their droppings. Do not blow at their bottoms. Wash eggs with detergent if soiled with faecal matter and cook and consume them immediately. Always wash hands thoroughly with soap and water after handling chickens and eggs;
- Eggs should be cooked well until the white and yolk become firm. Do not eat raw eggs or dip cooked food into any sauce with raw eggs. Poultry should be cooked thoroughly. If there is pinkish juice running from the cooked poultry or the middle part of its bone is still red, the poultry should be cooked again until fully done;
- Wash hands frequently, especially before touching the mouth, nose or eyes, before handling food or eating, and after going to the toilet, touching public installations or equipment such as escalator handrails, elevator control panels or door knobs, or when hands are dirtied by respiratory secretions after coughing or sneezing; and
- Wear a mask if fever or respiratory symptoms develop, when going to a hospital or clinic, or while taking care of patients with fever or respiratory symptoms.Ends/Friday, December 30, 2016Issued at HKT 19:15