Influenza activity notably drops in consecutive weeks
"Our latest surveillance data show that, after its peak in mid-July, the influenza activity has been on the decline as most parameters including laboratory surveillance, influenza-associated hospital admissions and institutional outbreaks have been decreasing in the past two to three weeks," a spokesman for the CHP said.
The positive percentage of seasonal influenza viruses among respiratory specimens received by the CHP peaked at 40.86 per cent in the week of July 9 and further dropped from 35.52 to 25.28 per cent from the week of July 23 to that of July 30.
In the same period, the number of institutional outbreaks of influenza-like illness substantially decreased from 39 (affecting 222 persons) to 15 (73 persons). As of yesterday (August 8), three (12 persons) had been recorded this week.
The average daily number of influenza cases admitted to public hospitals peaked at 350 per day in the seven-day period from July 11 to 17 and then steadily decreased to 135 per day recently (August 2 to 8).
Regarding severe influenza cases, in adults, 474 cases of influenza-associated admission to the Intensive Care Unit or death (including 337 deaths) were recorded from May 5 to yesterday in the enhanced surveillance with the Hospital Authority and private hospitals, as compared with 647 cases (501 deaths) and 409 cases (211 deaths) recorded in the enhanced surveillance periods for the winter influenza seasons in 2015 and 2016 respectively.
In children, in the same period, 19 cases of severe influenza-associated complication or death (three deaths) were detected. In 2017, there have been 27 cases (four deaths) so far.
The average daily number of severe cases among all ages peaked at 11.3 per day in the seven-day period from July 12 to 18 and then gradually decreased to 7.9 per day recently (August 2 to 8).
"As observed in previous seasons, we expect that local influenza will still be active for some time as it normally takes about two to three months for influenza activity to return to baseline from the peak. Influenza is also active in the temperate Southern Hemisphere, parts of Southeast Asia, southern provinces in the Mainland, Macau and Taiwan. We again advise members of the public and travellers to stay vigilant and calm and not panic as strict personal, hand and environmental hygiene remain the most effective means against influenza," the spokesman added.
The public and travellers should maintain good personal and environmental hygiene for protection against influenza and other respiratory illnesses both locally and during travel:
- Receive seasonal influenza vaccination for personal protection;
- Wash hands with liquid soap and water properly whenever possibly contaminated;
- When hands are not visibly soiled, clean them with 70 to 80 per cent alcohol-based handrub as an effective alternative;
- Cover the nose and mouth when sneezing or coughing, and wash hands thoroughly afterwards;
- Dispose of soiled tissue paper properly in a lidded rubbish bin;
- Put on a surgical mask when respiratory symptoms develop;
- Maintain good indoor ventilation;
- When influenza is prevalent, avoid going to crowded or poorly ventilated public places; high-risk individuals may consider putting on surgical masks in such places; and
- Maintain a balanced diet, exercise regularly, take adequate rest, do not smoke and avoid overstress.
The public may visit the CHP's influenza page and weekly Flu Express for more information. An analysis of the summer influenza season is carried in a thematic article in the earlier published bi-weekly Communicable Diseases Watch.
Ends/Wednesday, August 9, 2017
Issued at HKT 16:25
Issued at HKT 16:25
Public should observe strict hygiene amid very high influenza activity CHP appeals for heightened vigilance against sharp increase in influenza activity Surveillance enhanced amid influenza season Local influenza activity increased Influenza activity continues to drop in past month Influenza activity drops further Sustained hygiene advised beyond summer influenza season