TAIPEI (Taiwan News) -- As the flu season reaches its peak with nearly 100,000 struck in Taiwan last week, this year's government funded free vaccines are less effective against the influenza virus as the World Health Organization (WHO) had predicted the wrong strain, though they can still offer some protection, according to the Centers for Disease Control (CDC).
The WHO had recommended trivalent flu vaccines targeting the influenza A viruses (H1N1 and H3N2) and an influenza B virus of the Victoria lineage, but the majority of the flu cases this year in Taiwan are being caused by Type B of the Yamagata lineage. According to CDC data, over 97,000 cases of flu were recorded last week, a 24 percent increase from the week before, reported Liberty Times.
The CDC also reported 22 severe cases of the flu and two cases of people infected with the type B influenza dying. At a press conference, CDC physician Wu Pei-huan (吳佩圜) said that 18 of the 22 had not been vaccinated, while one of the dead was a woman in her 40s who had been vaccinated, but had a history of chronic illnesses.
Wu said that the second death was a man in his 70s who succumbed to pneumonia after contracting the Type B flu virus. He had not received the vaccine and did not have any known serious health conditions.
Huang Li-min (黃立民), a pediatrician specializing in infectious diseases at National Taiwan University Hospital, said that severity of this year's outbreak is similar to the past, with cases of pneumonia and encephalitis, but the more people are being infected this time around. He estimated that about two thirds of the patients contracted the Yamagata strain, while one third have been infected with Type A H3N2, and he anticipates that this year's outbreak will peak around mid January.
Despite being directed at different strains, CDC Deputy Director-General Chuang Jen-hsiang (莊人祥) said Tuesday that the vaccine can still provide up to 30 percent protection, reported CNA. The WHO said that while this vaccine will not achieve the 60 to 70 percent protection as originally expected, it still should reach about 30 to 50 percent effectiveness, which is enough to substantially reduce the risk of contracting severe infections.
Huang Kao-pin (黃高彬), Director of Pediatric Infectious Disease Department at CMU Children's Hospital, said that calling it the wrong vaccine is "too arbitrary," as nearly 6 million Taiwanese have been vaccinated, covering about 25 percent of the population. He said that it is difficult to quantify exactly what percentage of the population has contracted which strain, but it will offer crossover protection against other strains, and as long as at least 24 percent of the population is inoculated, it usually does not lead to a pandemic and there is no need to panic.
Once the influenza virus is confirmed, antiviral drugs should be taken as soon as possible. Since December, the CDC has expanded the provision of public antiviral drugs. Patients who have flu-like symptoms and those who have come in close contact with people with flu-like symptoms, such as classmates, colleagues, or family members, can have access to antiviral medications.