Evolutionary epidemiology of Neisseria meningitidis strains in Belarus compared to other European countries.

INTRODUCTION: Meningococcal infections are major causes of death in children globally. In Belarus, the incidence of cases and fatality rate of meningococcal infections are low and comparable to the levels in other European countries. AIM: In the present study, the molecular and epidemiological traits of Neisseria meningitidis strains circulating in Belarus were characterized and compared to isolates from other European countries. MATERIALS AND METHODS: Twenty N. meningitidis strains isolated from patients (n = 13) and healthy contacts (n = 7) during 2006­2012 in Belarus were selected for multilocus sequence typing (MLST), genosubtyping and FetA typing. TheSTs of the Belarusian strains were phylogenetically compared to the STs of 110 selected strains from 22 other European countries. RESULTS: Overall, eleven different genosubtypes were observed, there were seven variants of variable region of the fet Agene detected. The majority of the STs (95%) found in Belarus were novel and allthose were submitted to the Neisseria MLST database for assignment. Several newly discovered alleles of fumC (allele 451) and gdh (allele 560 and 621) appeared to be descendants of alleles which are widespread in Europe, and single aroE alleles (602 and 603) occurred as a result of separate evolution. CONCLUSIONS: N. meningitidis strains circulating in Belarus are heterogeneous and include sequence types, possibly, locally evolved in Belarus as well as representatives of widespread European hyperinvasive clonal complexes.

Cryptococcus neoformans strains and infection in apparently immunocompetent patients, China.

To determine the population structure of the cryptococcosis agents in China, we analyzed the genotype of 120 Cryptococcus neoformans and 9 Cryptococcus gattii strains isolated from 1980 through 2006 from cryptococcosis patients residing in 16 provinces of mainland China. A total of 71% (91/129) of the clinical strains isolated from 1985 through 2006 were from patients without any apparent risk factors. Only 8.5% (11/129) were from AIDS patients; the remaining 20.5% (27/129) were from patients with underlying diseases other than HIV infection. One hundred twenty of the 129 isolates were C. neoformans serotype A, mating type MATalpha strains that exhibited an identical M13-based VNI subtype, which was distinguishable from the reference VNI molecular type. The 9 remaining isolates were serotype B, MATalpha strains of C. gattii and portrayed a typical VGI molecular type. Data analyzed from multilocus sequences showed no variation and that these Chinese C. neoformans isolates belong to a cluster that has phylogenetically diverged from the VNI reference strain. Our finding that most cryptococcosis patients in China had no apparent risk factor is in stark contrast with reports from other countries.