Pneumococcal Disease (PD) describes a group of illnesses caused by the bacterium Streptococcus Pneumoniae, also known as Pneumococcus.
There are more than 90 sub-types of this bacterium. It affects both children and adults and is a major cause of morbidity and mortality worldwide. Serious pneumococcal infections are a global health problem but are vaccine-preventable.
Worldwide, a million children die from PD each year. In Singapore, up to 70 per 100,000 children less than 5 years old are affected by PD. Pneumococcus is also the most common cause of community-acquired pneumonia (CAP) accounting for 19-25% of all cases.
It is commonly found in the nose and throat of healthy children and adults, with as many as 4 serotypes carried at once. While not all individuals will get sick from Pneumococcus, anyone in whom the bacteria has colonized is a carrier, and can potentially infect others through airborne particles.
Although anyone can get PD, some are particularly at high-risk for the disease. They include infants, the elderly and individuals with chronic medical illnesses or weakened immune systems.
After Pneumococcus colonizes in the upper respiratory tract, it can cause
- Bacteraemia/Sepsis (infection of the blood),
- Meningitis (infection of the membrane of the spinal cord or brain)
- Pneumonia (infection of the lungs),
- Otitis Media (infection of the middle ear) and
- Sinusitis (infection of the sinuses).
Prompt treatment with antibiotics is usually effective. In recent years due to the emergence of antibiotic-resistant strains, particularly to penicillin, the treatment of PD has become more challenging and may need a longer hospital stay along with expensive alternative therapy.
The best way to protect against PD is through vaccination. Vaccines are generally safe and effective.
A single dose of PPSV (Pneumococcal Polysaccharide Vaccine) is protective against 23 of the most prevalent strains of the bacteria in adults. Vaccination with PPSV is recommended for:
- People aged 65 years and above
- Those who have a chronic medical illness such as Diabetes, heart, lung and liver diseases
- Those who have asthma or smoke cigarettes
- Those with a weakened immune system due to human immunodeficiency viral (HIV) infection or cancer
- People without a functioning spleen and those with sickle cell disease
- Residents of long-term care facilities such as nursing homes
For adults aged 65 and above
2 injections, at least 1 year apart are recommended.
Children younger than 2 years old
are at a higher risk for serious PD than older children, hence vaccination with PCV (Pneumococcal Conjugate Vaccine) is recommended for them. The number of doses and the intervals between doses depend on the child’s age. It is also part of the childhood vaccination schedule recommended by the National Immunisation Registry of Singapore.