Aetiological agents of meningitis in Zambia: Is there a need for a pneumococcal vaccine?

C. Lukwesa, J. Mwansa, R. Nakazwe
2012 International Journal of Infectious Diseases  
Methods: MLSA was done for 48 strains of VGS isolated from blood cultures of patients with IE by using concatenated sequences of the seven house-keeping genes map, pfl, pyk, ppaC, rpoB, soda, and tuf (http://www.eMLSA.net),. Nucleotide alignments and phylogenetic trees were constructed with the neighbour-joining method using single house-keeping genes and concatenated sequences of seven house-keeping genes in MEGA version 5.0. Results: Analysis of 36 strains out of 48 VGS was done, since six
more » ... done, since six Streptococcus oralis did not reach the required sequence length for the sodA gene when analysed by the MLSA software, and one Streptococcus mutans and five Streptococcus sanguinis did not amplify map gene by PCR. All the sequence clusters could be equated with recognized species and based on MLSA, twenty one were identified as Streptococcus oralis, six as Streptococcus gordonii, five as Streptococcus sanguinis, three as Streptococcus parasanguinis, and one as Streptococcus anginosus. Conclusion: Results of MLSA revealed that the closely related species of VGS fall into well-resolved clusters when compared to single gene-based identification. http://dx.Background: Staphylococcus aureus is a persistent human pathogen responsible for a variety of infections ranging from softtissue infections to bacteremia. The objective of this study was to determine the prevalence of a repertoire of toxin genes among Malaysian MRSA strains isolated over a four years period and the genetic relatedness of MRSA strains. Methods: One hundred eighty-eight strains (2003, 2004, 2007 and 2008) of methicillin-resistant S. aureus (MRSA) isolated from a tertiary hospital were screened for 20 genes encoding for extracellular virulence determinant (sea, seb, sec, sed, see, seg, seh, sei, sej, tst, eta, etb,etd) and adhesins (cna, etb, fnbA, fnbB, hlg, ica, sdrE) via PCR. The genetic relatedness of these strains was determined by PFGE, PCR-RFLP of coa gene and agr grouping. Results: Majority of the strains were tested positive for efb and fnbA (96% each), ica (78%) and hlg (59%) genes. A total of 101 strains were positive for at least one type of staphylococcal enterotoxin genes with sea being the predominant. Genes for seb, sed, see, seh, sej, eta and etb were not detected in any of the MRSA strains. The prevalence of sea, sec and ica among strains isolated in 2008 was increased significantly (p < 0.05) compared to 2003. Most of the strains were of agr type I (97.5%) followed by agr type II (1.2%) and agr type III (0.6%). Subtyping by PFGE and PCR-RFLP of coa gene produce 88 different pulsed-field profiles (F = 0.51-1.0) and 47 different patterns (F = 0.24-1.0), respectively.
doi:10.1016/j.ijid.2012.05.838 fatcat:w2nb3clzezfhfpkib5pp3tdzxe