The epidemiological investigation – including contact tracing – on Hong Kong’s 11th imported case of H7N9 continues, and today we learn that her two traveling companions, and one of the doctors she initially consulted, have now been located and are asymptomatic.
Two reports from Hong Kong’s CHP. First an investigation status update, followed by excerpts from the letter sent to local doctors informing them of the case, alerting them of the possibility of seeing additional cases, and providing additional details on the patient’s presentation and course of treatment.
The Department of Health (DH) today (December 29) reported the latest updates on the first confirmed human case of avian influenza A(H7N9) in Hong Kong this winter, and again urged the public to maintain strict personal, food and environmental hygiene both locally and during travel.
Further epidemiological investigations by the Centre for Health Protection (CHP) of the DH have so far located two travel collaterals who travelled with the patient to Shenzhen on December 13. According to them, the trio visited a wet market in Niulanqian, Bao'an, Shenzhen, bought vegetables, and did not purchase or have contact with live chickens sold there. Both travel collaterals have remained asymptomatic for more than 10 days (incubation period) since their last contact with the patient and have been put under medical surveillance.
Investigations also revealed that the patient had consulted two private doctors practising in the same clinic on December 19 and 23 respectively. While the CHP has reached one of the duo thus far, the other private doctor is now out of town and follow-up is under way.
According to the private doctor whom the CHP has reached, the patient did not reveal her travel history to the Mainland during consultation. The clinic staff have remained asymptomatic and have been put under medical surveillance. Tracing of the relevant clients who attended the clinic at the same time with the patient is under way.
In addition, the patient underwent a chest X-ray examination in a medical laboratory centre on December 23, and the CHP's follow-up is under way.
Investigations are ongoing.
Ends/Monday, December 29, 2014
Issued at HKT 18:56
And this letter sent to local doctors (similar ones were sent to hospitals):
Surveillance And Epidemiology Branch December 28, 2014
A Confirmed Case of Human Infection with Avian Influenza A(H7N9) virus and Activation of Serious Response Level of Government’s Preparedness Plan
I would like to draw your attention to a confirmed case of human infection with avian influenza A(H7N9) virus in Hong Kong. The patient is a 68-year-old Chinese woman who has hypertension. She lives with her husband in Tuen Mun in Hong Kong.
According to the patient's family, she developed fever and symptoms of influenza-like illness (ILI) on December 19 and consulted two private doctors on December 19 and 23. She subsequently developed shortness of breath on December 25 and attended Accident and Emergency Department (AED) of Tuen Mun Hospital (TMH). Chest X-ray taken at AED showed extensive right side pneumonia and she was admitted to TMH. She developed desaturation soon after admission. She was intubated and was transferred to intensive care unit for treatment on the same day. She is now in critical condition.
Her endotracheal aspirate, nasopharyngeal aspirate and nasopharyngeal swab were all tested positive for influenza A(H7N9) virus by polymerase chain reaction by the Centre for Health Protection (CHP)'s Public Health Laboratory Services Branch on December 27, 2014.
Preliminary epidemiological investigation revealed that the patient travelled to Longgang, Shenzhen on December 13 for a day trip and returned to Hong Kong on the same day. During the trip, she ate cooked chicken at her friend's residence in Longgang. The CHP is communicating with the Health and Family Planning Commission of Guangdong to investigate the source of her infection. The patient did not visit any wet market in Hong Kong during the incubation period. According to available information, this is likely to be an imported infection. The CHP is tracing the exposed close contacts of the patient and will provide them with antiviral presumptive treatment and put them under quarantine. CHP’s investigation is on-going.
In view of this confirmed case, the Government has raised the influenza response level from “Alert” Response Level to “Serious” Response Level under the Framework of Government’s Preparedness Plan for Influenza Pandemic. Prior to this case, ten imported cases of human infection with avian influenza A(H7N9) virus were recorded in Hong Kong since December 2013.
Cumulatively, a total of 470 confirmed human H7N9 cases have been reported since March 2013, including at least 184 deaths (as of December 27, 2014). These included 454 cases in Mainland China and 16 cases exported from Mainland China to Hong Kong (11), Taiwan (4) and Malaysia (1).
As the winter months approached, there has been increase in number of sporadic human cases of avian influenza A (H7N9) infection occurring in Mainland China. There have been 16 human H7N9 cases reported (as of December 27) with onset dates since the beginning of September. These 16 cases occurred in Xinjiang (6), Jiangsu (3), Guangdong (2), Zhejiang (2), Beijing (1), Fujian (1) and Shanghai (1). Based on the seasonal pattern of avian influenza viruses, it is likely that the disease activity of H7N9 in Mainland China may further increase in the winter and heightened vigilance is warranted.
In response to the newly confirmed case in Hong Kong, we have enhanced surveillance by activating zero reporting with both public and private hospitals. Private hospitals are obliged to report the number of suspected cases on a daily basis and a nil return is required (Appendix 1 and 2). We would like to urge you to pay special attention to those who presented with ILI or fever and had history of visiting wet market with live poultry or contact with poultry in Guangdong or other affected areas within the incubation period (i.e., 10 days before onset of symptoms). The list of affected areas is regularly updated and is available at the following webpage of the CHP website:
Any suspected case meeting the reporting criteria (available from: https://ceno.chp.gov.hk/casedef/casedef.pdf ) should be immediately reported to the Central Notification Office (CENO) of CHP via fax (2477 2770), phone (24772772) or CENO On-line (www.chp.gov.hk/ceno).
Please also contact the Medical Control Officer (MCO) of the Department of Health at pager: 7116 3300 (call - 3 - 9179) when reporting any suspected case. CHP will make arrangement to send the patient to regional public hospitals for isolation, testing and treatment. Besides, it is important to isolate the patient to minimize contact/exposure to staff and other patients and advise the patient to wear a surgical mask while waiting for transport.
For updates on the latest situation of avian influenza, please visit the CHP’s designated website at http://www.chp.gov.hk/en/view_content/24244.html.
Thank you for your ongoing support in combating communicable diseases.
(Dr. SK CHUANG)
for Controller, Centre for Health Protection
Department of Health