Two problems meet a pediatrician constantly and are usually taught apart: pharyngitis and pediatric vaccination. Pharyngitis is inflammation of the pharynx and tonsils, and it is most often viral. The clinical task is therefore not to recognise the illness but to find the minority of children whose sore throat is caused by group A Streptococcus (GAS), and to treat those children with the narrowest antibiotic that works. Pediatric vaccination is a routine schedule that has made most severe childhood infections rare. It also involves reasoning about vaccine types, timing and the coverage that keeps those infections rare.
What do the two topics have in common?
They are the same argument at two scales.
For one child, the question is whether an antibiotic is justified and which one, so that the drug still works next time. This discipline is called antibiotic stewardship.
For a population, the question is what proportion must be immune for a pathogen to stop circulating. The purpose is that people who cannot be vaccinated are protected anyway, and this indirect protection is called herd immunity.
Both come down to intervening precisely: not more than the situation requires, and not less.
Where should a reader start?
Because the reasoning has to be learned in two places, start where the problem is. If it is a child with a sore throat, start with the sore-throat notes. There are four, to be read in order, and each answers the question the previous one raises. The four vaccine notes can be read without the pharyngitis notes. In the order listed, they move from how a vaccine works, to what the schedule prevents, to what happens when a population stops following it.
The sore-throat notes
- Pediatric Pharyngitis: Pathogens and Clinical Picture covers which viruses and bacteria cause a sore throat, how the presentation changes with the child’s age, and why the examination cannot separate viral from bacterial causes. It leaves the question of why one organism deserves the whole effort.
- Pediatric Group A Streptococcus: Virulence and Complications covers what the organism does after it reaches the throat, the two complications that appear weeks later, and the invasive form of the disease.
- Pediatric GAS Pharyngitis: Diagnosis covers how to establish that the organism is present: how to take a throat swab so that it means something, what a rapid antigen test can and cannot rule out, what a culture adds, and where clinical scores help.
- Pediatric GAS Pharyngitis: Treatment and Antibiotic Stewardship applies stewardship to the confirmed case: amoxicillin at the streptococcal dose rather than the pneumococcal one, the ten-day course and why it exists, the treatment window, and the drugs that should not be used.
The vaccine notes
- Pediatric Vaccines: Types and the Italian Schedule covers the six vaccine platforms, why each pathogen demands a particular platform, what adjuvants and excipients are, and what the Italian calendar gives at each age.
- Pediatric Vaccine-Preventable Diseases: The Mandatory Schedule covers the ten diseases the mandatory vaccinations prevent, each with its mechanism, the complication that justifies prevention, and the vaccine detail.
- Pediatric Vaccines Outside the Mandatory Schedule covers the six diseases prevented by vaccines Italy offers but does not require, from pneumococcus and meningococcus to rotavirus, HPV, influenza and hepatitis A.
- Pediatric Vaccination Coverage and Herd Immunity covers how much of a population has to be immune, why the threshold differs between diseases, and what has followed falling coverage in Italy and Europe.
Related topics
Scarlet Fever is the same organism presenting with a rash, and community-acquired pneumonia is the lower-airway presentation that pneumococcal vaccination helps prevent. Both are worth reading if the febrile child is the clinical problem in front of you.
But first, which sore throats in a child deserve an antibiotic at all?