The health authorities have called on the public to get vaccinated against influenza as surveillance data shows a rise in flu cases and vaccines may start to run out. The positive rate for seasonal flu viruses rose steadily from 1.22 per cent in the week ending December 12 to 5.18 per cent last week among respiratory specimens analysed by the Centre for Health Protection. Doctors Union president Dr Henry Yeung Chiu-fat said his clinic observed a spike in the number of cross-border patients asking for the influenza vaccine in recent weeks, possible due to the recent bird flu cases in Guangdong. Around 10 patients, usually children, were getting the injections in his private clinic every day. Many of them were new immigrants or mainlanders who lived in Guangdong. READ MORE: Five things you need to know about flu season in Hong Kong this year He expected his stock on the medicine to last until March. “As usual, people rushed to get flu jabs when they heard there were cases, “ Yeung said. On Thursday, the Centre for Health Protection said Guangdong had reported two human cases of H7N9 bird flu. But the bird flu strain that jumps from poultry to humans cannot be prevented by the seasonal influenza vaccine. Nevertheless, the vaccine this year has so far offered good protection against the major prevailing strains. “ I did not see a shortage of flu vaccine. But we need to prepare more stock as the flu activity is rising,” Yeung said. Among flu virus types detected last week, 51 per cent were A(H1N1)pdm09 while 28 per cent were of the B variety. The number of outbreaks of flu-like illnesses in institutions and schools rose from four last week, affecting 34 people, to eight affecting 33 people this week up until Wednesday. The flu-associated admission rate in public hospitals among children aged under five and elderly people aged 65 or above increased respectively from 0.21 and 0.03 cases per 10,000 people in the week ending December 12 to 0.61 and 0.08 respectively last week. From October last year until January 10, about 350,000 doses of seasonal flu vaccine were administered under the government vaccination programme (GVP), while about 170,000 were given under the vaccination subsidy scheme, making a total of about 520,000 , an increase of 22 per cent compared to the same period in 2014/15. READ MORE: Hong Kong’s first ‘flu forecasts’ to predict timing and scale of outbreaks just like the weather, HKU scientists say “Regarding the GVP’s stock, less than 50,000 doses are now left. We expect that they may be depleted shortly around Lunar New Year. Eligible groups yet to be vaccinated should do so early for better protection before the influenza season arrives,” a centre spokesman said. Vaccination services will continue until all doses are used up. The public can visit the GVP page ( www.chp.gov.hk/en/view_content/18630.html ) for a list of general outpatient clinics and elderly health centres where vaccines are still available. The Centre for Health Protection hotline on 2125 2125 is available for inquiries during office hours. Eligible people can also receive subsidised shots from private doctors under the scheme whereby each jab is subsidised to the tune of HK$160.