ABSTRACT
Background: Viral hemorrhagic fevers are emergent and endemic in Africa and in South America. In Côte d’Ivoire, Yellow fever cases were reported yearly and the distribution of mosquitoes in the country are the main factors for high incidence of Flaviviruses. The poorly reporting of viral hemorrhagic fever cases in some regions, the lack of international interest land and the underestimation of molecular surveillance method contribute to increase the risk for public health. Objectives: To evaluate the performance of molecular diagnostic methods in national surveillanceof two emergent Flaviviruses, Yellow fever virus and Dengue virus in Côte d’Ivoire. Study Design: 63 sera from suspected cases in 2010-2011 of viral hemorrhagic fevers were analyzed to detect viral RNA of Flaviviruses and to compare the results in three different methods. Results and Conclusion: The Flavivirus RT-PCR has showed the high molecular detection by12% and 6% for real time PCR. The methods are specific and high sensitive for the screening of tick and mosquito-borne Flaviviruses in clinical samples. This study confirms the high circulation of Flaviviruses and the introduction of Dengue virus in Côte d’Ivoire. The combination of real time PCR and the Flavivirus RT-PCR contribute to ameliorate the detection panel of molecular detection in Côte d’Ivoire and was a suitable method for the National Laboratory Reference.
ABSTRACT
Background: Buruli ulcer (BU) is neglected skin disease caused by Mycobacterium ulcerans. The lack of early diagnosis and treatment causes severe disability. In Central and in West Africa, BU is endemic and its control is difficult because the most cases occur in rural regions. The molecular particularity of M. ulcerans was the acquisition of the virulence plasmid pMUM001. Genetic analyses have demonstrated the high diversity with variable number tandem repeats (VNTR) and Mycobacterial Interspersed Repetitive Units (MIRU) in M. ulcerans and in mycolactone producing Mycobacteria (MPMs) Objective: The objective of this study was to investigate the molecular diversity by using MIRUVNTR method in clinical samples of BU patients in Côte d’Ivoire. Study Design: 21 clinical samples were collected from BU patients in different sites and were first analyzed in molecular diagnosis of BU using two targets insertion sequence IS2404 and keto reductase-B-domain (KR). In a second step, we have analyzed the strains by PCR typing for four specific and sensitive markers MIRU1, VNTR6, ST-1 and VNTR19. Results and Conclusion: 100% of clinical samples were positive in molecular tests for IS2404 and 95% for KR and confirm M. ulcerans in the samples. By PCR typing, we have found 61.9 % positive for MIRU1 and 52%, 85.7%, and 61.9% for VNTR6, ST-1 and VNTR19 respectively. One of sample was negative for all genotyping markers. Two different genetic profiles were identified by MIRU1 and ST-1 loci by gel-analyzed of the amplified products. The VNTR profile C (3,1,1) corresponding of 3 copies MIRU1, 1 copy VNTR6 and 1 copy ST-1 was detected in 28.5% of samples and confirms the West African genotype in Côte d’Ivoire. Different genetic strains of M. ulcerans were co-circulated in the same endemic region in the country. This study has described first the circulating of different genetic strains of M. ulcerans in Côte d’Ivoire.