Key Points

• Following the emergence of COVID-19 and the implementation of preventive measures across the country in 2020, a sharp decline in incidence was observed across all age groups, in contrast to the previous year, when an upward trend had been noted among children under 2 years of age, those aged 5–14, and adults aged 65 and older.

• In 2020, the highest incidence rates remained those of infections caused by serotypes not included in the VPC13 vaccine (particularly serotypes 8 and 22F in adults, and serotype 24F in children), as well as serotype 3 (included in the VPC13) in adults. Serotypes 8 (not included in the PCV13) and 3 (included in the PCV13) nevertheless account for a smaller proportion of cases among those under 15 years of age compared to the previous year, while they remain the most frequently observed among those 15 years of age and older. While the non-vaccine serotype 24F still accounts for a significant proportion of cases among children under 5 years of age, the non-vaccine serotypes 10A and 23B have increased, respectively, among children under 2 years of age and those aged 2–4 years. Among adults aged 65 and older, the main serotypes observed remain 8 and 3. Furthermore, consistent with the previous year, the non-vaccine serotypes 24F and 23B accounted for the highest proportions of penicillin-resistant strains in 2020, while serotypes 8, 3, 10A, and 22F did not show any particular resistance to this treatment, according to data from the CNR for pneumococci.

• Trends in the major serotypes associated with cases of invasive pneumococcal disease observed in France during the pandemic will need to be confirmed in the coming years and will help guide vaccination strategies in the years ahead. Monitoring the distribution of serotypes will also be necessary to contribute to the evaluation of new vaccines, including VPC15 (VPC13+22F and 33F) and VPC20 (VPC13 + 8, 10A, 11A, 12F, 15B, 22F, 33F).