Friday, January 06, 2017

Hong Kong: CHP Update On H7N9 Investigation









#12,090



Hong Kong's CHP has published the following update, confirming overnight news reports that their latest H7N9 case has died, and summarizing the epidemiological investigation on this, and late December's, imported case.

First their statement, then I'll return with a bit more.

 
     The Centre for Health Protection (CHP) of the Department of Health today (January 6) reported an update on the third human case of avian influenza A(H7N9) in Hong Kong this winter.

     The male patient, aged 62, passed away in the small hours today in Yan Chai Hospital (YCH). Contact tracing has so far identified 33 close contacts and 90 other contacts.

     Close contacts include the patient's family contacts as well as relevant in-patients and healthcare workers (HCWs) of YCH. An HCW with mild symptoms is pending testing and the others 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 other family members, other relevant in-patients, visitors and HCWs of YCH, personnel involved upon his arrival in Hong Kong and ambulance personnel involved in patient transfer. All remain 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. For those in-patients with underlying illnesses or higher risk of complications, they will also be given Tamiflu for five days as a precautionary measure.
 
     Regarding the second human H7N9 case this winter reported on December 30, 2016, further epidemiological investigations revealed that the patient's residence in Zhongshan from December 14 to 16 last year was opposite a wet market with live poultry stalls and there were also mobile stalls selling live poultry outside the market. Based on information available thus far, it has been classified as an imported case. The patient was hospitalised in Princess Margaret Hospital in serious condition.
 
     From 2013 to date, 19 imported human H7N9 cases have been confirmed in Hong Kong, with seven deaths (37 per cent).
 
     In addition, the CHP is closely monitoring an additional human H7N9 case in Shandong. According to the Health and Family Planning Commission of Rizhao Municipality, the patient is a man aged 77.
 
     "As H7N9 virus continues to be detected in animals and environments in the Mainland, additional human cases are expected in affected and possibly neighbouring areas. Epidemiological experience in the past few years shows that most imported human H7N9 cases were detected in Hong Kong in the first quarter. In view of the heavy trade and travel between the Mainland and Hong Kong, further sporadic human cases in Hong Kong every now and then are expected, especially in the coming few months," a spokesman for the CHP said.
 
     "Therefore, we again urge the public to avoid touching birds, poultry or their droppings and visiting poultry markets or farms during travel, particularly in the upcoming Lunar New Year holidays. If feeling unwell, such as having a 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 actively inform the doctors of their travel history for prompt diagnosis and treatment," the spokesman added.
 
Ends/Friday, January 6, 2017

Issued at HKT 18:13

With the addition of 16 cases announced yesterday (see CIDRAP's H7N9 activity intensifies in China with 16 more cases by Lisa Schnirring) the number of cases reported at this stage of the season is nearly 4 times what it was during last year's (admittedly down) epidemic.

Given the limits of surveillance - essentially only those who are sick enough to be hospitalized are usually ever tested - and China's history of belated reporting (we may yet hear of more cases from December), we are admittedly working with incomplete information. 

The encouraging news - so far, at least - is that we've not seen any large (and very few small) clusters of cases, most cases are linked to live bird exposure, and contacts of known cases rarely test positive for the virus. 
That could change, of course.  H7N9 is evolving, as are H5N6, H5N1, H5N8, and every other novel (or seasonal) flu virus out there. 
In last month's MMWR: Assessing The 4th Epidemic Wave Of H7N9 In China, researchers stated that `using the Influenza Risk Assessment Tool (10), CDC found that A(H7N9) virus has the highest potential pandemic risk of any novel influenza A viruses that have been assessed.'

So we watch it, and a growing list of other up-and-coming novel viruses, very closely.