Impact of 13-valent pneumococcal conjugate vaccine on laboratory-confirmed pneumococcal meningitis and purulent meningitis among children ˂5 years in Cameroon, 2011-2018

• Published in: PloS one Vol. 16; no. 4; p. e0250010
• Main Authors: Njuma Libwea, John, A Fletcher, Mark, Koki Ndombo, Paul, Boula, Angeline, Ashukem, Nadesh Taku, Ngo Baleba, Madeleine, Kingue Bebey, Rachel Sandrine, Nkolo Mviena, Eric Gaston, Tageube, Jean, Kobela Mbollo, Marie, Koulla-Shiro, Sinata, Madhi, Shabir, Njanpop-Lafourcade, Berthe-Marie, Mohammad, Ali, Begier, Elizabeth, Southern, Joanna, Beavon, Rohini, Gessner, Bradford
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 15.04.2021; Public Library of Science (PLoS)
• Subjects: Age; Bacterial meningitis; Biology and Life Sciences; Cerebrospinal fluid; Children; Children & youth; Clinical trials; Conjugates; Data collection; Decision analysis; Demographic aspects; Developing countries; Drug dosages; Editing; Emerging markets; Funding; Health surveillance; Hospitals; Immunization; Infectious diseases; Laboratories; LDCs; Medical research; Medicine; Medicine and Health Sciences; Meningitis; Methodology; People and Places; Physiological aspects; Pneumonia; Prevention; Public health; Research and Analysis Methods; Reviews; Schedules; Serotypes; Social sciences; Streptococcus infections; Surveillance; Testing; Vaccines; Visualization; Finland; New York; Cameroon; United States > US; Africa; South Africa; France; Sub-Saharan Africa
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0250010

The 13-valent pneumococcal conjugate vaccine (PCV13) entered Cameroon's childhood national immunization programme (NIP) in July 2011 under a 3-dose schedule (6, 10, 14 weeks of age) without any catch-up. We described the impact of PCV13 onserotype distribution among pneumococcal meningitis cases over time. We used laboratory-based sentinel surveillance data to identify meningitis cases among 2- to 59-month-old children with clinically-suspected bacterial meningitis (CSBM) admitted to hospitals in Yaoundé (August 2011-December 2018). Purulent meningitis cases had a cerebrospinal fluid (CSF) white blood cell (WBC) count ≥20 per mm3. Pneumococcal meningitis cases had S. pneumoniae identified from CSF, with serotyping by polymerase chain reaction. Years 2011-2014 were described as early PCV13 era (EPE) and years 2015-2018 as late PCV13 era (LPE) impact periods. Among children hospitalized with CSBM who had a lumbar puncture obtained, there was no significant change from the EPE versus the LPE in the percentage identified with purulent meningitis: 7.5% (112/1486) versus 9.4% (154/1645), p = 0.0846. The percentage of pneumococcal meningitis cases due to PCV13 vaccine-serotype (VST) decreased from 62.0% (31/50) during the EPE to 35.8% (19/53) in the LPE, p = 0.0081. The most frequent pneumococcal meningitis VSTs during the EPE were 6A/6B (30%) and 5 (6%), and during the LPE were 14 (13.2%), 3 (7.6%), 4 (5.6%) and 18C (5.6%). Four to seven years after PCV13 introduction, the proportion of pneumococcal meningitis due to vaccine serotypes has declined, mainly due to reductions of serotypes 6A/6B, 1, 19A, and 23F; nevertheless, PCV13 VSTs remain common. Because the analyzed surveillance system was not consistent or population based, we could not estimate incidence or overall impact; this emphasizes the need for improved surveillance to document further the utility of PCV13 immunization in Cameroon.