Sunday, July 02, 2017

A Look At Taiwan's Out Of Season Flu Surge


Since early May we've been following an unusually severe, late season flu surge in Hong Kong - one that has claimed more than 100 lives in the past 60 days (see Hong Kong's Late Season Flu Surge Continues To Increase) - and have taken note of a similar, but less severe outbreak in Taiwan.
While Hong Kong often sees a biphasic or `double peaked’  flu season (see chart below), their second wave doesn't usually occur until July or August, and is usually milder and of shorter duration. Taiwan, like Hong Kong, normally sees their flu season peak in February or March. 
Credit HK Flu Express

This year, both Taiwan and Hong Kong reported a relatively mild winter-spring flu season, which seemed ready to end by mid April.  Over the past 2 months, however, both have reported an unusual late season surge in severe influenza cases.  

Hong Kong, with a population 1/4th that of Taiwan, has reported far more fatalities since early May (102 vs 18), but otherwise both outbreaks have similarities.

Each saw spikes in influenza positive lab sampling starting in early May (see comparison chart below), both report predominantly (80%+) H3N2, and both continue to climb 8 weeks into their second wave.

Since May 5th Hong Kong has reported 143 severe cases, and 102 deaths while over the roughly the same time span Taiwan has reported 315 severe cases, but only 18 deaths.
Exactly why Hong Kong is reporting a significantly higher fatality rate among severe cases isn't immediately apparent. 
Today Taiwan's CDC issued the following (translated) press release (bolding mine) indicating that influenza cases continue to rise and hospital ER's are clogged with flu cases.

 Press release

The outbreak of the outbreak, the Department of Health to thank the emergency medical staff of the hard, and once again called on the public if flu-like symptoms, the implementation of medical diversion, so that all patients get appropriate medical treatment

According to the monitoring data show that the first 26 weeks (as of 7/1) emergency influenza treatment of 21,584 people, compared with the previous week (20,742 person-time), according to the monitoring data show that the 26th week (as of 7/1) ) Increased by 842 people, indicating that the current influenza epidemic continued, at a high level; the other by the emergency single-day attendance data analysis, on Sunday emergency class influenza treatment times as twice as usual, the Department of Emergency medical staff in this effort to pay Expressed a high degree of gratitude and affirmation, and once again called on the public if the flu symptoms, please go to the public welfare influenza antiviral contract clinic for medical treatment, to avoid concentrating to the hospital emergency; but if breathing difficulties, rapid, cyanosis (hypoxia), blood sputum Or sputum thickening, chest pain, changes in consciousness, hypotension and other signs of influenza risk, you should be as soon as possible to the largest hospital for treatment.

In view of the immediate monitoring effect, the CDC will automatically transmit the information such as health insurance diagnostic codes for emergency visits to the Department through more than 170 responsible hospitals in the country. The emergency diagnostic code contains hundreds of diagnostic codes (such as attachments) for acute upper respiratory tract infection and influenza, and the coding definition has not been changed after the transfer to ICD-10 on January 1, 2016.
The number of emergencies in the 26th week (as of 7/1) was 21,584, an increase of 842 (4%) from the previous week (20,742), and the upward trend was slower than the last five flu season A week before the Spring Festival (week 5) 22,529 people; another Sunday emergency flu on a single day visit 5,000 people, for the average daily average of about 2,600 times. The flu season (July 1 last year) as of this year 26 weeks (as of 7/1) accumulated 859 cases, of which 79 cases died. At present, the number of episodes of influenza and the number of deaths in the past six months were cumulative in the same period.

Laboratory monitoring data show that the current community of influenza virus type is still H3N2-based, nearly 4 weeks of antigenicity monitoring data show that 85% H3N2 virus and influenza vaccine strains coincide, but this year's influenza epidemic situation is different from previous years, may With the last year, the amount of influenza vaccination doubled and play a role in suppressing the winter epidemic, the other vaccination has been more than six months, the decline in protection, and this year's climate and other factors under the influence of slow, resulting in the delay occurred.

Disease Control Department reminds the public once again to keep the hands clean, pay attention to respiratory hygiene and cough etiquette, if you have respiratory symptoms, should wear a mask, sneeze handkerchief to cover the nose and mouth or sleeve replacement, sick not work class, Public places or crowded places, to maintain indoor air circulation, reduce the chance of virus transmission, and called on people to implement medical diversion.
The Commission has extended the use of influenza antiviral antiviral drugs to extend the use of the period to July 31, the public if the respiratory symptoms, to the country more than 3,000 contract medical institutions for medical treatment, where the doctor determined to meet the conditions of use of public drugs , Without fast screening, can be used in accordance with the provisions of the public anti-viral agents. Information can be found on the CDU Global Information Network ( or by calling the Free Epidemic Prevention Line 1922 (or 0800-001922).

The most recent Influenza Express Report (week 25) from Taiwan's CDC summarizes the activity as follows:

As I mentioned on Thursday, except for a Hong Kong, Taiwan, and a spike in flu cases in New South Wales, influenza activity around the world appears to be running at seasonal normals; low in the northern hemisphere and slowly climbing in the southern hemisphere.
Although the timing and severity of Taiwan and Hong Kong's outbreaks are a bit odd, we've seen nothing to suggest anything unusual about the viruses being reported by health officials.
We will, however, keep a close eye on both outbreaks and on Australia's upcoming flu season, as they may provide us with some hint as to what to expect next fall in the Northern Hemisphere.

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