Nationwide Trends in Bacterial Meningitis before the Introduction of 13-Valent Pneumococcal Conjugate Vaccine-Burkina Faso, 2011-2013.

BACKGROUND: Following introduction of Haemophilus influenzae type b vaccine in 2006 and serogroup A meningococcal conjugate vaccine in 2010, Streptococcus pneumoniae (Sp) became the leading cause of bacterial meningitis in Burkina Faso. We describe bacterial meningitis epidemiology, focusing on pneumococcal meningitis, before 13-valent pneumococcal conjugate vaccine (PCV13) introduction in the pediatric routine immunization program in October 2013. METHODS: Nationwide population-based meningitis surveillance collects case-level demographic and clinical information and cerebrospinal fluid (CSF) laboratory results. Sp infections are confirmed by culture, real-time polymerase chain reaction (rt-PCR), or latex agglutination, and CSF serotyped using real-time and conventional PCR. We calculated incidence rates in cases per 100,000 persons, adjusting for age and proportion of cases with CSF tested at national reference laboratories, and case fatality ratios (CFR). RESULTS: During 2011-2013, 1,528 pneumococcal meningitis cases were reported. Average annual adjusted incidence rates were 26.9 (<1 year), 5.4 (1-4 years), 7.2 (5-14 years), and 3.0 (≥15 years). Overall CFR was 23% and highest among children aged <1 year (32%) and adults ≥30 years (30%). Of 1,528 cases, 1,036 (68%) were serotyped: 71% were PCV13-associated serotypes, 14% were non-PCV13-associated serotypes, and 15% were non-typeable by PCR. Serotypes 1 (45%) and 12F/12A/12B/44/46 (8%) were most common. Among children aged <1 year, serotypes 5 (15%), 6A/6B (13%) and 1 (12%) predominated. CONCLUSIONS: In Burkina Faso, the highest morbidity and mortality due to pneumococcal meningitis occurred among children aged <1 year. The majority of cases were due to PCV13-associated serotypes; introduction of PCV13 should substantially decrease this burden

Pneumococcal Carriage in Burkina Faso After 13-Valent Pneumococcal Conjugate Vaccine Introduction: Results From 2 Cross-sectional Population-Based Surveys

Background: Burkina Faso, a country in Africa's meningitis belt, introduced 13-valent pneumococcal conjugate vaccine (PCV13) in October 2013, with 3 primary doses given at 8, 12 and 16 weeks of age. To assess whether the new PCV13 program controlled pneumococcal carriage, we evaluated overall and serotype-specific colonization among children and adults during the first 3 years after introduction. Methods: We conducted 2 population-based, cross-sectional, age-stratified surveys in 2015 and 2017 in the city of Bobo-Dioulasso. We used standardized questionnaires to collect sociodemographic, epidemiologic, and vaccination data. Consenting eligible participants provided nasopharyngeal (all ages) and oropharyngeal (≥5 years only) swab specimens. Swab specimens were plated onto blood agar either directly (2015) or after broth enrichment (2017). Pneumococci were serotyped by conventional multiplex polymerase chain reaction. We assessed vaccine effect by comparing the proportion of vaccine-type (VT) carriage among colonized individuals from a published baseline survey (2008) with each post-PCV survey. Results: We recruited 992 (2015) and 1005 (2017) participants. Among children aged &lt;5 years, 42.8% (2015) and 74.0% (2017) received ≥2 PCV13 doses. Among pneumococcal carriers aged &lt;1 year, VT carriage declined from 55.8% in 2008 to 36.9% in 2017 (difference, 18.9%; 95% confidence interval, 1.9%-35.9%; P = .03); among carriers aged 1-4 years, VT carriage declined from 55.3% to 31.8% (difference, 23.5%; 6.8%-40.2%; P = .004); and among participants aged ≥5 years, no significant change was observed. Conclusion: Within 3 years of PCV13 implementation in Burkina Faso, we documented substantial reductions in the percentage of pneumococcal carriers with a VT among children aged &lt;5 years, but not among persons aged ≥5 years. More time, a change in the PCV13 schedule, or both, may be needed to better control pneumococcal carriage in this setting.</p

Aggregate and case-based meningitis surveillance data indicators, Burkina Faso, 2011–2015.

<p>Aggregate and case-based meningitis surveillance data indicators, Burkina Faso, 2011–2015.</p

Annual incidence (cases per 100,000 persons) of suspected, probable and laboratory-confirmed meningitis, Burkina Faso, 2011–2015.

<p>Annual incidence (cases per 100,000 persons) of suspected, probable and laboratory-confirmed meningitis, Burkina Faso, 2011–2015.</p

Bacterial meningitis epidemiology and return of <i>Neisseria meningitidis</i> serogroup A cases in Burkina Faso in the five years following MenAfriVac mass vaccination campaign

<div><p>Background</p><p>Historically, <i>Neisseria meningitidis</i> serogroup A (NmA) caused large meningitis epidemics in sub-Saharan Africa. In 2010, Burkina Faso became the first country to implement a national meningococcal serogroup A conjugate vaccine (MACV) campaign. We analyzed nationwide meningitis surveillance data from Burkina Faso for the 5 years following MACV introduction.</p><p>Methods</p><p>We examined Burkina Faso’s aggregate reporting and national laboratory-confirmed case-based meningitis surveillance data from 2011–2015. We calculated incidence (cases per 100,000 persons), and described reported NmA cases.</p><p>Results</p><p>In 2011–2015, Burkina Faso reported 20,389 cases of suspected meningitis. A quarter (4,503) of suspected meningitis cases with cerebrospinal fluid specimens were laboratory-confirmed as either <i>S</i>. <i>pneumoniae</i> (57%), <i>N</i>. <i>meningitidis</i> (40%), or <i>H</i>. <i>influenzae</i> (2%). Average adjusted annual national incidence of meningococcal meningitis was 3.8 (range: 2.0–10.2 annually) and was highest among infants aged <1 year (8.4). <i>N</i>. <i>meningitidis</i> serogroup W caused the majority (64%) of meningococcal meningitis among all age groups. Only six confirmed NmA cases were reported in 2011–2015. Five cases were in children who were too young (n = 2) or otherwise not vaccinated (n = 3) during the 2010 MACV mass vaccination campaign; one case had documented MACV receipt, representing the first documented MACV failure.</p><p>Conclusions</p><p>Meningococcal meningitis incidence in Burkina Faso remains relatively low following MACV introduction. However, a substantial burden remains and NmA transmission has persisted. MACV integration into routine childhood immunization programs is essential to ensure continued protection.</p></div

Average adjusted annual incidence of laboratory-confirmed meningitis by pathogen and age group, Burkina Faso, 2011–2015.

<p>Abbreviations: Hi, <i>H</i>. <i>influenzae</i>; NmA, <i>N</i>. <i>meningitidis</i> serogroup A; NmC, <i>N</i>. <i>meningitidis</i> serogroup C; NmW, <i>N</i>. <i>meningitidis</i> serogroup W; NmX, <i>N</i>. <i>meningitidis</i> serogroup X; NmY, <i>N</i>. <i>meningitidis</i> serogroup Y; Sp, <i>S</i>. <i>pneumoniae</i>.</p

Adjusted annual incidence of meningococcal meningitis by serogroup, Burkina Faso, 2011–2015.

<p>Abbreviations: Nm, <i>N</i>. <i>meningitidis</i>; NmA, <i>N</i>. <i>meningitidis</i> serogroup A; NmC, <i>N</i>. <i>meningitidis</i> serogroup C; NmW, <i>N</i>. <i>meningitidis</i> serogroup W; NmX, <i>N</i>. <i>meningitidis</i> serogroup X; NmY, <i>N</i>. <i>meningitidis</i> serogroup Y.</p

Suspected, probable and laboratory-confirmed meningitis cases from case-based meningitis surveillance, Burkina Faso, 2011–2015.

<p>Suspected, probable and laboratory-confirmed meningitis cases from case-based meningitis surveillance, Burkina Faso, 2011–2015.</p

Reported <i>N</i>. <i>meningitidis</i> serogroup A cases, Burkina Faso, 2011–2015.

<p>Reported <i>N</i>. <i>meningitidis</i> serogroup A cases, Burkina Faso, 2011–2015.</p

The meningitis belt of sub-Saharan Africa and meningococcal serogroup A conjugate vaccine (MACV) rollout, 2010–2016.

<p>The meningitis belt of sub-Saharan Africa and meningococcal serogroup A conjugate vaccine (MACV) rollout, 2010–2016.</p