Education Corner
Pneumococcal infection
Pneumococcal infection represents a wide range of diseases caused by the bacterium Streptococcus pneumoniae (S. pneumoniae / pneumococcus). More than 90 serotypes have been identified. It can be transmitted by droplet spread and contact with respiratory secretions; direct contact is another way of transmission.
S.pneumoniae causes a wide spectrum of diseases, including:
- meningitis: it is a severe type of pneumococcal infection and usually presents with fever, stiff neck and mental confusion, causing long-term problems, such as hearing loss, or even death;
- pneumonia: it commonly presents with fever, shortness of breath, chills and productive cough, and may result in death in severe cases; and
- otitis media: it presents with fever, ear pain with or without ear discharge, and may lead to hearing loss in recurrent cases.
Pneumococcal Conjugate Vaccine (PCV)
A. Why get vaccinated?
Pneumococcal conjugate vaccine (PCV) can effectively protect against severe invasive infections due to the serotypes of S. pneumoniae contained in the vaccine. Children aged below 2 years are at risk to severe invasive pneumococcal infection (i.e. meningitis, bacteraemic pneumonia and septicaemia) and are advised to get vaccinated. In Hong Kong, PCV13 (vaccine consisting of antigens against thirteen pneumococci serotypes) is included in the Hong Kong Childhood Immunisation Programme.
The Scientific Committee on Vaccine Preventable Diseases recommends individuals aged 2 to 64 years with certain high risk conditions* to receive 23-valent pneumococcal polysaccharideas well as PCV 13. For more details, please refer to the following link:
*High risk conditions include:
- History of invasive pneumococcal disease
- Immunocompromised states:
- Asplenia, HIV /AIDS , primary immunodeficiency
- Immunodeficiencies related to malignancies and transplantation
- Immunodeficiencies related to use of immunosuppressive drugs / systemic steroid
- Chronic disease
- Chronic cardiac, pulmonary, liver or renal disease
- Diabetes mellitus or Cerebrospinal fluid leakage
- With cochlear implants
(Essential hypertension per se is not considered as a high risk condition)
Different factors such as age and clinical condition may affect the risk of pneumococcal disease. Patients with high-risk conditions should discuss with their attending doctors on the most appropriate vaccination regimen.
B. When should my child get vaccinated?
A child is advised to receive 3 doses of PCV13 in the first year of life (at 2 months, 4 months and 6 months old), and another booster dose at 12 months old.
C. The following individuals should NOT receive PCV
- serious allergic reaction to previous dose of PCV
- serious allergic reaction to diphtheria toxoid containing vaccine
D. What are the side effects?
- Most people have no serious reactions after receiving PCV.
- Occasionally there may be mild fever (usually occur within 3 days after vaccination) or slight redness or swelling around the injection site, but these will gradually subside in a few days. If fever or discomforts persist, or abnormal breathing is observed, please consult a doctor immediately.
E. How many types of PCV are available in HK and what are their protection?
There are more than 1 type of PCV available in the market of Hong Kong but no one PCV can cover all serotypes of Streptococcus pneumoniae. Personal and environmental hygiene are important measures in preventing pneumococcal infection.