RESUMO
RESUMEN Objetivo Describir las características fenotípicas y genotípicas de cepas de Neisseria meningitidis aisladas de enfermedad meningocócica en Paraguay entre 1996 y 2015. Métodos Se estudiaron por métodos microbiológicos convencionales y técnicas moleculares 114 aislamientos de N. meningitidis y 12 muestras clínicas sin aislamiento confirmadas por reacción en cadena de la polimerasa (PCR) que fueron remitidas por los diferentes centros centinelas y centros colaboradores de Paraguay. Resultados El grupo de edad más afectado fue el de menores de 1 año (19,0%), seguido por el de 1 a 5 años (17,5%). Un mayor porcentaje de las cepas se aisló de casos de meningitis (81,7%) y el serogrupo B se encontró en 60,3% de los casos. Los fenotipos más frecuentes fueron B:4:P1.14 (16,0%), B:15:P1.5, C:NT:NST y W:NT:P1.2 (10,5%), respectivamente. Los complejos clonales prevalentes fueron ST-11/ET37 complex 29,6% (8/27) con predominio del serogrupo W (6/8), ST-35 complex 18,5% (5/27) en el serogrupo B (4/4), y ST-32/ET5 complex 14,8% (4/16) en el serogrupo B (5/5). Conclusiones En Paraguay la enfermedad meningocócica es relativamente infrecuente. Los análisis de distribución de serogrupo muestran que el más frecuente es el B y en los últimos dos años aumentaron los casos de enfermedad meningocócica por C y W. Los complejos clonales encontrados se correlacionan con los hallados en la región del Cono Sur. Debido al alto nivel de virulencia de N. meningitidis, su vigilancia debe constituir una prioridad estratégica de los sistemas de salud pública nacionales y regionales para prevenir brotes epidémicos y apoyar la toma de decisiones en salud pública.
ABSTRACT Objective Describe the phenotypical and genotypical characteristics of Neisseria meningitidis isolates from cases of meningococcal disease in Paraguay between 1996 and 2015. Methods Conventional microbiological methods and molecular techniques were used to study 114 isolates of N. meningitidis and 12 clinical samples without isolation (confirmed by polymerase chain reaction), provided by various sentinel centers and collaborating centers in Paraguay. Results The most affected age group was children under 1 year (19.0%), followed by 1-5-year-olds (17.5%). The highest percentage of strains was isolated in meningitis cases (81.7%) and serogroup B was found in 60.3% of cases. The most frequent phenotypes were B:4:p1.14 (16.0%), B:15:p1.5, C:nt:nst, and W:nt:p1.2 (10.5%), respectively. The prevalent clonal complexes were: ST-11/ET37 complex, 29.6% (8/27), predominantly serogroup W (6/8); ST-35 complex, 18.5% (5/27), in serogroup B (4/4); and ST-32/ET5 complex, 14.8% (4/16), in serogroup B (5/5). Conclusions Meningococcal meningitis is relatively uncommon in Paraguay. Distribution analysis showed that serogroup B is the most common and that the number of cases of meningococcal disease caused by serogroups C and W increased in the last two years. The identified clonal complexes were correlated with those found in the Southern Cone region. Due to the high virulence of N. meningitidis, its surveillance should be a strategic priority of national and regional public health systems to prevent epidemic outbreaks and support public health decision-making.
RESUMO Objetivo Descrever as características fenotípicas e genotípicas de cepas de Neisseria meningitidis isoladas de casos de doença meningocócica no Paraguai entre 1996 e 2015. Métodos Foram estudados por métodos microbiológicos convencionais e técnicas moleculares 114 isolados de N. meningitidis e 12 amostras clínicas sem isolamento confirmadas por reação em cadeia da polimerase (PCR) enviados por diferentes centros-sentinela e centros colaboradores do Paraguai. Resultados A faixa etária mais afetada foi a de crianças menores de 1 ano (19,0%) e crianças de 1 a 5 anos (17,5%). Uma maior porcentagem de cepas foi isolada de casos de meningite (81,7%) e o sorogrupo B foi identificado em 60,3% dos casos. Os fenótipos mais comuns foram B:4:P1.14 (16,0%), B:15:P1.5, C:NT:NST e W:NT:P1.2 (10,5%), respectivamente. Os complexos clonais mais prevalentes foram o complexo ST-11/ET37 (29,6%, 8/27) com predomínio no sorogrupo W (6/8), complexo ST-35 (18,5%, 5/27) no sorogrupo B (4/4) e complexo ST-32/ET5 (14,8%, 4/16) no sorogrupo B (5/5). Conclusões A doença meningocócica é relativamente pouco comum no Paraguai. A análise da distribuição dos sorogrupos demonstrou que o sorogrupo B é o mais prevalente e, nos últimos dois anos, ouve um aumento nos casos de doença meningocócica pelos sorogrupos C e W. Os complexos clonais encontrados se correlacionam com os achados na região do Cone Sul. Devido à alta virulência da N. meningitidis, a vigilância deste agente deve ser uma prioridade estratégica dos sistemas de saúde pública nacionais e regionais para prevenir surtos epidêmicos e subsidiar a tomada de decisão em saúde pública.
Assuntos
Paraguai/epidemiologia , Meningite/genética , Neisseria meningitidis/isolamento & purificaçãoRESUMO
Background & objectives: Meningitis caused by Neisseria meningitidis is a fatal disease. Meningococcal meningitis is an endemic disease in Delhi and irregular pattern of outbreaks has been reported in India. All these outbreaks were associated with serogroup A. Detailed molecular characterization of N. meningitidis is required for the management of this fatal disease. In this study, we characterized antigenic diversity of surface exposed outer membrane protein (OMP) FetA antigen of N. meningitidis serogroup A isolates obtained from cases of invasive meningococcal meningitis in Delhi, India. Methods: Eight isolates of N. meningitidis were collected from cerebrospinal fluid during October 2008 to May 2011 from occasional cases of meningococcal meningitis. Seven isolates were from outbreaks of meningococcal meningitis in 2005-2006 in Delhi and its adjoining areas. These were subjected to molecular typing of fetA gene, an outer membrane protein gene. Results: All 15 N. meningitides isolates studied were serogroup A. This surface exposed porin is putatively under immune pressure. Hence as a part of molecular characterization, genotyping was carried out to find out the diversity in outer membrane protein (FetA) gene among the circulating isolates of N. meningitidis. All 15 isolates proved to be of the same existing allele type of FetA variable region (VR) when matched with global database. The allele found was F3-1 for all the isolates. Interpretation & conclusions: There was no diversity reported in the outer membrane protein FetA in the present study and hence this protein appeared to be a stable molecule. More studies on molecular characterization of FetA antigen are required from different serogroups circulating in different parts of the world.