Pneumococcal disease is often prevented
Posted on 8 June 2017
The introduction of the pneumococcal vaccination has been dubbed the most cost-effective public health intervention in the history of medicine by some experts. Pneumococcal disease is caused by bacteria so in theory antibiotics should treat it. But with rising antibiotic resistance, the pneumococcal vaccination is now estimated to prevent millions of deaths annually.
Pneumococcal disease is caused by the Streptococcus pneumoniae (Pneumococcus) bacteria that can spread from person to person through close contact or droplet spread (such as sneezing). It can cause mild infections such as ear or sinus infections but can also lead to invasive pneumococcal disease, most commonly resulting in:
- Bacteraemia/septicaemia (an infection in the bloodstream).
- Meningitis (an infection in the covering of the brain and spinal cord).
- Pneumonia (an infection in the tissues of the lungs that causes inflammation of the airspaces in the lungs). Pneumonia is invasive if it is associated with bacteraemia/sepsis.
Pneumococcus has more than 90 variants (serotypes), but only a few produce the majority of invasive pneumococcal diseases. In fact, the 10 most common types are estimated to cause more than half of all invasive diseases worldwide.
Those under 5 or over 65 are particularly vulnerable to invasive pneumococcal disease because of their underdeveloped or ageing immune systems, as are those with compromised immune systems due to immunosuppressive illnesses or immunosuppressant medication. The majority of deaths or disabilities associated with childhood pneumococcal disease occur in Africa.
In 2009 South Africa became the first country in Africa to incorporate the pneumococcal conjugate vaccine (PCV) into the national vaccination programme, called the Expanded Programme on Immunisation (EPI).
In April 2013 the pneumococcal vaccine (called PCV13) that protects against 13 types of pneumococcal bacteria replaced the earlier version of the vaccination (PCV7, protecting against seven types). The PCV7 already contained many antibiotic resistant strains of the diseases but PCV13 included six more serotypes to offer even broader protection against Pneumococcus.
A case-control study was done in South Africa on the earlier version, PCV7. The study showed the vaccination to be effective for reducing pneumococcal disease by 90% in children without immunosuppressive illnesses.
And more recently, ‘after the switch from PCV7 to PCV13, the first published study from South Africa (entailing national laboratory-based surveillance) showed a decline in overall cases of invasive pneumococcal disease’. More specifically, the cases declined from just under 55 cases per 100 000 children under two years old, to 17 cases per 100 000 children, according to a 2017 paper published in The Lancet (Robert Cohen, Corinne Levy).
According to the EPI schedule the PCV13 vaccine is given:
- At 6 weeks of age
- At 14 weeks
- At 9 months
High-risk adults in South Africa (those over 65, those with immunosuppressive illnesses or taking immunosuppressant medication) have two options for the pneumococcal vaccination:
- The PCV13 vaccination
- The PSV23 vaccine made from 23 different strains of Pneumococcus. This version of the vaccination is found to be ineffective in small children owing to their immature immune systems combined with the chemical make-up of the vaccination.
The two vaccinations cannot be given at the same time, so the recommendation is to give the PCV13 vaccine first and then the PSV23 vaccine between six months to a year later, according to a pamphlet in The Lancet.
If you have any concerns about the side effects of the vaccination, these should be discussed with your child’s paediatrician or your GP. Otherwise, simply follow your child’s vaccination schedule, given to you in hospital or speak to your GP or pharmacist about receiving the vaccination as an adult.
Hampton LM, Farley MM, Schaffner W, et al. Prevention of antibiotic-nonsusceptible Streptococcus pneumoniae with conjugate vaccines. J Infect Dis 2012; 205:401-411