Cristina Méndez

Newer higher valency pneumococcal conjugate vaccines (PCVs) have the potential to reduce the adult community-acquired pneumonia (CAP) burden. We describe the evolution and distribution of adult community-acquired pneumonia (CAP) serotypes in Spain, focusing on serotypes contained in the 20-valent PCV (PCV20). This was a prospective, observational study of chest X-ray (CXR)-confirmed CAP in immunocompetent adults hospitalized in one of four Spanish hospitals between November 2016 and November 2020. Pneumococci were isolated from cultures and detected in urine using BinaxNow^® and Pfizer serotype-specific urinary antigen tests UAD1 and UAD2. We included 1948 adults hospitalized with CXR-CAP. The median age was 69.0 years (IQR: 24 years). At least one comorbidity was present in 84.8% (n = 1653) of patients. At admission, 76.1% of patients had complicated pneumonia. Pneumococcus was identified in 34.9% (n = 680) of study participants. The PCV20 vaccine-type CAP occurred in 23.9% (n = 465) of all patients, 68.4% (n = 465) of patients with pneumococcal CAP, and 82.2% (83/101) of patients who had pneumococcus identified by culture. Serotypes 8 (n = 153; 7.9% of all CAP) and 3 (n = 152; 7.8% of all CAP) were the most frequently identified. Pneumococcus is a common cause of hospitalized CAP among Spanish adults and serotypes contained in PCV20 caused the majority of pneumococcal CAP.

Pneumococcal disease is a major cause of morbidity/mortality worldwide, and vaccination is an important measure in its prevention. Despite European children being vaccinated with pneumococcal conjugate vaccines (PCVs), pneumococcal infections are still a major cause of morbidity/mortality in adults with risk conditions and their vaccination might be an important prevention strategy. New PCVs have been approved, but information is lacking on their potential impact in European adults. In our review, we searched PubMed, MEDLINE, and Embase for studies on the additional PCV20 serotypes (concerning incidence, prevalence, disease severity, lethality, and antimicrobial resistance) in European adults, between January 2010 and April 2022, having included 118 articles and data from 33 countries. We found that these serotypes have become more prevalent in both invasive and non-invasive pneumococcal disease (IPD and NIPD), representing a significant proportion of cases (serotypes 8, 12F, 22F) and more serious disease and/or lethality (10A, 11A, 15B, 22F), showing antimicrobial resistance (11A, 15B, 33F), and/or affecting more vulnerable individuals such as the elderly, immunocompromised patients, and those with comorbidities (8, 10A, 11A, 15B, 22F). The relevance of pneumococcal adult carriers (11A, 15B, 22F, and 8) was also identified. Altogether, our data showed an increase in the additional PCV20 serotypes’ prevalence, accounting for a proportion of approximately 60% of all pneumococcal isolates in IPD in European adults since 2018/2019. Data suggest that adults, as older and/or more vulnerable patients, would benefit from vaccination with higher-coverage PCVs, and that PCV20 may address an unmet medical need.

The real burden of community-acquired pneumonia (CAP) in non-hospitalized patients is largely unknown. This is a 3-year prospective, observational study of ambulatory CAP in adults, conducted in 24 Spanish primary care centers between 2016–2019. Sociodemographic and clinical variables of patients with radiographically confirmed CAP were collected. Pneumococcal etiology was assessed using the Binax Now^® test. Patients were followed up for 10 ± 3 days. A total of 456 CAP patients were included in the study. Mean age was 56.6 (±17.5) years, 53.5% were female, and 53.9% had ≥1 comorbidity. Average incidence of CAP was 1.2–3.5 cases per 1000 persons per year. Eighteen patients (3.9%) were classified as pneumococcal CAP. Cough was present in 88.1% of patients at diagnosis and fever in 70.8%. Increased pulmonary density (63.3%) and alveolar infiltrates with air bronchogram (16.6%) were the most common radiographic findings. After 14.6 ± 6.0 days (95% CI = 13.9–15.3), 65.4% of patients had recovered. Hospitalization rate was 2.8%. The most frequently prescribed antibiotics were quinolones (58.7%) and β-lactams (31.1%). In conclusion, one-third of CAP patients did not fully recover after two weeks of empiric antibiotic therapy and 2.8% required hospitalization, highlighting the significant burden associated with non-hospitalized CAP in Spain.

This study aimed to assess the costs and clinical benefits of the 13-valent pneumococcal conjugate vaccine (PCV13) administered annually to the 65-year-old cohort in Spain versus the alternative of not vaccinating patients and treating them only when infected.