Aetiology of bacterial meningitis in infants aged <90 days: Prospective surveillance in Luanda, Angola

Background: Despite effective antibiotics and vaccines, bacterial meningitis (BM) remains one of the leading causes of morbidity and mortality in young infants worldwide. Data from Africa on the aetiology and antibiotic susceptibility are scarce. Objective: To describe the aetiology of BM in Angolan infants <90 days of age. Methods: A prospective, observational, single-site study was conducted from February 2016 to October 2017 in the Paediatric Hospital of Luanda. All cerebrospinal fluid samples (CSF) from infants aged <90 days with suspected BM or neonatal sepsis were assessed. The local laboratory performed microscopy, chemistry, culture, and susceptibility testing. PCR for vaccine-preventable pathogens was performed in Johannesburg, South Africa. Results: Of the 1287 infants, 299 (23%) had confirmed or probable BM. Of the 212 (16%) identified bacterial isolates from CSF, the most common were Klebsiella spp (30 cases), Streptococcus pneumoniae (29 cases), Streptococcus agalactiae (20 cases), Escherichia coli (17 cases), and Staphylococcus aureus (11 cases). A fifth of pneumococci (3/14; 21%) showed decreased susceptibility to penicillin, whereas methicillin-resistant S. aureus (MRSA) was encountered in 4/11 cases (36%). Of the gram-negative isolates, 6/45 (13%) were resistant to gentamicin and 20/58 (34%) were resistant to third-generation cephalosporins. Twenty-four percent (33/135) of the BM cases were fatal, but this is likely an underestimation. Conclusions: BM was common among infants <90 days of age in Luanda. Gram-negative bacteria were predominant and were often resistant to commonly used antibiotics. Continued surveillance of the antibiogram is pivotal to detect potential changes without delay.