Wednesday, January 10, 2018

Taiwan & Hong Kong Both Report Heavy Flu Activity

ILI Emergency Visits Taiwan














#13,051


While most regions of the world only have to contend with one severe flu season per year, both Kong Kong and Taiwan are embroiled in their second serious flu epidemic in the past 6 months. 
Last summer, both were hard hit by an `out-of-season' H3N2 epidemic that easily eclipsed their regular winter/spring epidemic of 2017 (see Hong Kong's Summer Flu Appears To Have Peaked).
While Hong Kong is known for having a biphasic or `double peaked’  flu season, their heaviest activity usually occurs between February and April with a less severe season in mid to late summer (see Seasonality of Influenza A(H3N2) Virus: A Hong Kong Perspective (1997–2006).

Over the past couple of weeks we've seen increased reports of influenza in both Taiwan & Hong Kong (see Seasonal Flu Reports Increasing Across China, Asia) and this week levels have reached epidemic proportions.
Unlike last summer, the culprit currently appears to be influenza B (Yamagata Lineage), which is also reported to be widespread across much of China (see China: NHFPC Statement On Current Flu Epidemic).
Today both Hong Kong and Taiwan have issued seasonal flu alerts. First stop, Hong Kong:
     The Centre for Health Protection (CHP) of the Department of Health today (January 10) announced that local seasonal influenza activity has continued to increase in the past week and exceeded the baseline level, indicating that Hong Kong has entered the 2017-18 winter influenza season. The community should heighten vigilance and maintain personal protection against influenza.
 
     The positive percentage of seasonal influenza viruses among respiratory specimens received by the CHP increased from 9.76 per cent in the week ending December 30 to over 15 per cent in the following week. The circulating influenza viruses in the past week were predominantly influenza B, with low influenza A activity.

     In the above period, the weekly average rate of the influenza-like illness (ILI) syndrome group in the accident and emergency departments increased from 195.3 cases per 1 000 coded cases to 208.8. The overall admission rate with principal diagnosis of influenza in public hospitals increased from 0.26 per 10 000 population to 0.40.
 
     After the Christmas and New Year holidays, the CHP recorded an increase in institutional ILI outbreaks from two (affecting six persons) in the week ending December 30 to five (affecting 21 persons) last week. In the first three days of this week, 13 ILI outbreaks (affecting 46 persons) have been recorded. The above outbreaks occurred in primary schools (eight), residential care homes for the elderly (five), kindergartens/child care centres (five), a residential care home for the disabled (one) and a hospital (one).
 
     The CHP has collaborated with public hospitals under the Hospital Authority and private hospitals to monitor influenza-associated admissions to intensive care units (ICU) and deaths among patients aged 18 years or above as routine surveillance throughout the year starting in 2018. As of yesterday (January 9), 24 cases (10 deaths) had been recorded. Of note, the causes of ICU admission or death among the cases may be due to other acute medical conditions or underlying diseases. Starting tomorrow (January 11), the weekly surveillance data on adult severe influenza cases will be reported in the CHP’s Flu Express published every Thursday.

     In children aged under 18, routine surveillance of severe influenza-associated complications or deaths is ongoing. As of yesterday, one case had been recorded this year. In 2015, 2016 and 2017, 25 (one death), 31 (four deaths) and 27 (four deaths) cases were recorded respectively. Among them, 73 cases (88 per cent) did not receive seasonal influenza vaccination for the respective season.
 
     "We anticipate that local seasonal influenza activity will continue to rise in the coming weeks and remain at an elevated level for some time. We again urge the public, particularly children, the elderly and chronic disease patients, to observe strict personal, hand and environmental hygiene," a spokesman for the CHP said.
 
     The CHP will issue letters to doctors, hospitals, institutions and schools again to appeal for heightened vigilance and appropriate actions.
 
     "According to the latest data, the currently circulating viruses in Hong Kong, including the influenza B and influenza A H1 and H3 viruses, were antigenically similar to the components of the northern hemisphere influenza vaccine adopted in the 2017-18 Government Vaccination Programme and Vaccination Subsidy Scheme," the spokesman said.
         (Continue . . . )


Next, this from the Taiwan CDC:



The domestic influenza epidemic has entered the epidemic period, the total number of emergency cases in the country last week (101,364) was slightly higher than the previous week, and the percentage of emergency patients continued to rise, coupled with the recent cold snap, cold conditions will make the flu virus more active, people because of the cold wind closed doors and windows, may increase the risk of viral transmission.
The CDC has launched the "Peak influenza contingency plan", but also to remind people should pay attention to indoor ventilation and must do well in hand hygiene and cough etiquette, such as influenza symptoms, please wear a mask as soon as possible to the nearest doctor and medication according to the doctor's advice, to prevent the outbreak.


To reduce the threat to people's health caused by the pandemic, the CDC said will continue to promote the contingency planning of the various prevention and treatment, including the strengthening of surveillance, expand the use of antiviral drugs, improve the quality of severe medical care and resource scheduling, and enhance risk communication, and remind the relevant units to strengthen population density (such as the long photo agency , correctional institutions, etc.)/medical/barracks/school (structure) infection control measures to prevent influenza clustering events.


In addition, the CDC has sent free influenza antiviral agents to more than 4,000 contract medical institutions in the counties and cities of the country, remind the public not to ignore the severity of influenza, such as influenza-like symptoms should be the nearest medical treatment, where the doctor's clinical judgement to determine the conditions of drug use at public expense (such as attachment), do not need fast screen, you can open a public medicine. In particular, adults over 50 years of age, infants, high-risk chronic diseases and pregnant women and other high-risk groups should pay attention to their own health status, if there is no immediate medical treatment, to grasp the opportunity to reduce serious disease risk.

The CDC reiterates its appeal to the public to implement frequent hand washing and respiratory symptoms wearing masks, as far as possible to avoid crowds crowded, the air is not circulating public places, as well as sick not to work, not classes, etc. to avoid the spread of the virus. If you have flu-related questions, you can go to the CDC Global Information Network "Influenza Zone" (https://www.cdc.gov.tw), or call the domestic toll-free immunization hotline 1922 (or 0800-001922) for consultation.
        (Continue . . . .)
Shift from Influenza A(H3N2) to Influenza B
Shift from A/(H3N2) to Influenza B
While mid-winter is traditionally prime time for Influenza A epidemics - with China, Taiwan & Hong Kong all coming off a big summer of H3N2 - lingering community immunity appears to opened the door to a more influenza B dominated winter. 
We'll have to see if Asia sees a late season switch back to influenza A, and whether regions (like North America) currently battling H3N2, will see a second  influenza B peak later in the spring. 
Hopefully not, but given the topsy-turvy year of flu we're seeing, nothing seems off the table.


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