Dr Yeung Ho Hong 楊浩康 醫生 health-prevention-info

health-prevention-info
Pneumococcal Vaccine (肺炎鏈球菌疫苗)

Dr Yeung Ho Hong ( 楊浩康 醫生 ) 2021-08-10

Pneumococcal Vaccine (肺炎鏈球菌疫苗)

肺炎球菌感染一般只會引起較輕微的感染,但是肺炎鏈球菌可以引致嚴重和致命感染,例如入血性肺炎、腦膜炎和敗血病。現時已有13價肺炎球菌結合疫苗,和23價肺炎球菌多醣疫苗,可以有效預防肺炎鏈球菌的感染。

Pneumococcal infection refers to diseases caused by Streptococcus pneumoniae. Streptococcus pneumoniae can survive on the human body and is commonly found in the upper respiratory tract. Healthy people can also be carriers of Streptococcus pneumoniae. Streptococcus pneumoniae can be spread through droplets or oral contact, or indirect contact with objects contaminated by respiratory secretions.

In most situations, Streptococcus pneumoniae will only cause less severe infections, such as otitis media or sinusitis. But Streptococcus pneumoniae can cause serious and fatal infections, such as severe pneumonia, meningitis, and sepsis, which we call invasive pneumococcal diseases. If children and the elderly suffer from invasive pneumococcal disease, their conditions are usually more serious.

There are vaccines that can effectively prevent pneumococcal infection, including 13-valent pneumococcal conjugate vaccine (PCV13) and 23-valent pneumococcal polysaccharide vaccine (23vPPV). The 13-valent pneumococcal conjugate vaccine is not only effective in preventing invasive pneumococcal disease, but also prevents non-invasive pneumonia caused by streptococcus pneumoniae. The 23-valent pneumococcal polysaccharide vaccine can also prevent invasive pneumococcal disease, but its effectiveness in preventing non-invasive pneumonia caused by streptococcus pneumoniae is not ideal. But in theory, the 23-valent pneumococcal polysaccharide vaccine can provide additional protection because it contains more serotypes.

The Scientific Committee on Vaccine Preventable Diseases recommends that children under the age of 2 should be vaccinated with 13-valent pneumococcal conjugate vaccine. The current recommendation is two doses vaccine at 2 months and 4 months of age, followed by a booster dose at 1 year old. The Scientific Committee also recommends that people aged 2 years or older with high-risk conditions should receive a 13-valent pneumococcal conjugate vaccine followed by 23-valent pneumococcal polysaccharide vaccine one year later.