Characterization of strains of Neisseria meningitidis causing meningococcal meningitis in Mozambique, 2014: Implications for vaccination against meningococcal meningitis.

INTRODUCTION: In sub Saharan Africa, the epidemiology, including the distribution of serogroups of strains of N. meningitidis is poorly investigated in countries outside "the meningitis belt". This study was conducted with the aim to determine the distribution of serogroups of strains of N. meningitidis causing meningococcal meningitis in children and adults in Mozambique. METHODS: A total of 106 PCR confirmed Neisseria meningitidis Cerebrospinal Fluid (CSF) samples or isolates were obtained from the biobank of acute bacterial meningitis (ABM) surveillance being implemented by the National Institute of Health, at three central hospitals in Mozambique, from January to December 2014. Serogroups of N. meningitidis were determined using conventional PCR, targeting siaD gene for Neisseria meningitidis. Outer Membrane Proteins (OMP) Genotyping was performed by amplifying porA gene in nine samples. RESULTS: Of the 106 PCR confirmed Neisseria meningitidis samples, the most frequent serotype was A (50.0%, 53/106), followed by W/Y (18.9%, 20/106), C (8.5%, 9/106), X (7.5%, 8/106) and B (0.9%, 1/106). We found non-groupable strains in a total of 15 (14.2%) samples. PorA genotypes from nine strains showed expected patterns with the exception of two serogroup C strains with P1.19,15,36 and P1.19-36,15 and one serogroup X with P1.19,15,36, variants frequently associated to serogroup B. CONCLUSION: Our data shows that the number of cases of meningococcal meningitis routinely reported in central hospitals in Mozambique is significant and the most dominant serogroup is A. In conclusion, although serogroup A has almost been eliminated from the "meningitis belt", this serogroup remains a major concern in countries outside the belt such as Mozambique.

Serotype distribution and antimicrobial resistance of Streptococcus pneumoniae in children with acute bacterial meningitis in Mozambique: implications for a national immunization strategy.

BACKGROUND: S. pneumoniae is the leading cause of acute bacterial meningitis (ABM) in children. Vaccination using the 10-valent conjugate vaccine (PCV-10) was recently introduced into the National Immunization Program in Mozambique, but data on serotype coverage of this vaccine formulation are scarce. In this study, we investigated the serotype distribution and antimicrobial resistance of isolates of S. pneumoniae causing ABM in children < 5 years at the two largest hospitals in Mozambique. METHODS: Between March 2013 and March 2014, a total of 352 cerebrospinal fluid (CSF) samples were collected from eligible children, of which 119 (33.8 %) were positive for S. pneumoniae. Of these, only 50 samples met the criteria for serotyping and were subsequently serotyped using sequential multiplex PCR (SM-PCR), but 15 samples were non-typable. RESULTS: The most common serotypes of S. pneumoniae were 1 (18.2 %), 5 (15.2 %), 14 (12.1 %), 9 V (12.1 %), 23 F (9.1 %), 6A (9.1 %), 4 (9.1 %) and 6B (6.1 %). Serotypes 1, 5, 9 V, 6A and 12 were mostly prevalent in Northern Mozambique, while serotypes 23 F, 4, 6B, 3 and 15B were predominant in Southern. Serotype coverage of PCV-10 and PCV-13 vaccine formulations were 81.8 % and 93.9 %, respectively. Serotypes 1, 3, 4, 6B, 14, 23 F were resistant to penicillin and sensitive to ceftriaxone. CONCLUSIONS: Our findings shows that changing the current in use PCV-10 vaccine formulation to PCV-13 formulation might increase substantially the protection against invasive strains of S. pneumoniae as the PCV-10 vaccine formulation does not cover the serotypes 3 and 6A, which are prevalent in Mozambique.

Frequency of Pathogenic Paediatric Bacterial Meningitis in Mozambique: The Critical Role of Multiplex Real-Time Polymerase Chain Reaction to Estimate the Burden of Disease.

BACKGROUND: In Sub-Saharan Africa, including Mozambique, acute bacterial meningitis (ABM) represents a main cause of childhood mortality. The burden of ABM is seriously underestimated because of the poor performance of culture sampling, the primary method of ABM surveillance in the region. Low quality cerebrospinal fluid (CSF) samples and frequent consumption of antibiotics prior to sample collection lead to a high rate of false-negative results. To our knowledge, this study is the first to determine the frequency of ABM in Mozambique using real-time polymerase chain reaction (qPCR) and to compare results to those of culture sampling. METHOD: Between March 2013 and March 2014, CSF samples were collected at 3 regional hospitals from patients under 5 years of age, who met World Health Organization case definition criteria for ABM. Macroscopic examination, cytochemical study, culture, and qPCR were performed on all samples. RESULTS: A total of 369 CSF samples were collected from children clinically suspected of ABM. qPCR showed a significantly higher detection rate of ABM-causing pathogens when compared to culture (52.3% [193/369] versus 7.3% [27/369], p = 0.000). The frequency of Streptococcus pneumoniae, Haemophilus influenzae, group B Streptococci, and Neisseria meningitidis were 32.8% (121/369), 12.2%, (45/369), 3.0% (16/369) and 4.3% (11/369), respectively, significantly higher compared to that obtained on culture (p < 0.001 for each). CONCLUSION: Our findings demonstrate that culture is less effective for the diagnosis of ABM than qPCR. The common use of culture rather than qPCR to identify ABM results in serious underestimation of the burden of the disease, and our findings strongly suggest that qPCR should be incorporated into surveillance activities for ABM. In addition, our data showed that S. pneumoniae represents the most common cause of ABM in children under 5 years of age.

A prospective observational study of bacteraemia in adults admitted to an urban Mozambican hospital.

BACKGROUND: Bacteraemia is a common cause of fever among patients presenting to hospitals in sub-Saharan Africa. The worldwide rise of antibiotic resistance makes empirical therapy increasingly difficult, especially in resource-limited settings. OBJECTIVES: To describe the incidence of bacteraemia in febrile adults presenting to Maputo Central Hospital (MCH), an urban referral hospital in the capital of Mozambique, and characterise the causative organisms and antibiotic susceptibilities. We aimed to describe the antibiotic prescribing habits of local doctors, to identify areas for quality improvement. METHODS: Inclusion criteria were: (i) ≥18 years of age; (ii) axillary temperature ≥38°C or ≤35°C; (iii) admission to MCH medical wards in the past 24 hours; and (iv) no receipt of antibiotics as an inpatient. Blood cultures were drawn from enrolled patients and incubated using the BacT/Alert automated system (bioMérieux, France). Antibiotic susceptibilities were tested using the Kirby-Bauer disc diffusion method. RESULTS: Of the 841 patients enrolled, 63 (7.5%) had a bloodstream infection. The most common isolates were Staphylococcus aureus, Escherichia coli, and non-typhoidal Salmonella. Antibiotic resistance was common, with 20/59 (33.9%) of all bacterial isolates showing resistance to ceftriaxone, the broadest-spectrum antibiotic commonly available at MCH. Receipt of insufficiently broad empirical antibiotics was associated with poor in-hospital outcomes (odds ratio 8.05; 95% confidence interval 1.62 - 39.91; p=0.04). CONCLUSION: This study highlights several opportunities for quality improvement, including educating doctors to have a higher index of suspicion for bacteraemia, improving local antibiotic guidelines, improving communication between laboratory and doctors, and increasing the supply of some key antibiotics.

Aetiology of sexually transmitted infections in Maputo, Mozambique.

INTRODUCTION: The study sought to ascertain the prevalence of the aetiological agents of genital discharge and genital ulcer diseases in Maputo, Mozambique. METHODOLOGY: Consecutive consenting patients presenting to the Centro de Saúde do Porto in Maputo between March and April 2005 with genital discharge syndrome and/or genital ulcer diseases were recruited. Specimens were collected for the identification of STI pathogens. RESULTS: Of 346 recruited patients, 164 were male and 182 female. The prevalence of confirmed single aetiological agents for male urethritis was as follows: N. gonorrhoeae, 35%; C. trachomatis, 10%; and M. genitalium 4%. For vaginal discharge, N. gonorrhoeae was found in 11% of the women tested, followed by C. trachomatis (6.5%), bacterial vaginosis (34%), and T. vaginalis (2%). The prevalence of genital ulcers was as follows: Herpes simplex virus type 2, 62%; H. ducreyi 4 %; and C. trachomatis biovar LGV, 4%. Five percent of patients with genital ulcers had a positive syphilis serology (RPR ≥ 1:8 and confirmed by TPHA) and 35% of all tested patients were HIV-1/2 infected. Cases of mixed infections were present in 5%, 11% and 3% of patients with male urethritis, vaginal discharge, and genital ulcers respectively. CONCLUSION: The classic sexually transmitted infection aetiologies are still prevalent in Maputo. The study highlights the need for a periodic surveillance to inform syndromic management protocols.