Prafulla Dutta1, Siraj Ahmed Khan1, Naba Kumar Hazarika2, Sumi Chetry1. 1. Arbovirology Group, Entomology Division, Regional Medical Research Centre, Dibrugarh, Assam, India. 2. Department of Microbiology, Gauhati Medical College and Hospital, Guwahati, Assam, India.
Abstract
PURPOSE: Northeast Region of India possesses an abundant number of Aedes mosquitoes, the common vector for Dengue and Chikungunya (CHIK). Dengue is reported every year from Assam, but active surveillance for CHIK virus (CHIKV) infection is lacking in this part of India. Therefore, this present study has been undertaken to detect any CHIKV infection during a dengue outbreak in Assam. MATERIALS AND METHODS: A total of 42 dengue negative samples collected from Guwahati were screened for the presence of CHIK IgM antibodies. Further, all the samples were processed for CHIKV RNA detection by reverse transcriptase-polymerase chain reaction (RT-PCR). Phylogenetic analysis was done by Maximum Likelihood method using Kimura-2 parameter model. RESULTS: No IgM positivity was found in the processed samples; however, 7 samples were positive for CHIKV by RT-PCR. Phylogenetic analysis revealed that the circulating CHIKV belonged to Eastern, Central and Southern African genotype. Sequence analysis showed two uniform nucleotide substitutions and very less amino acid substitution. CONCLUSION: Silent existence of CHIKV beside dengue is reported from this study. Therefore, CHIKV diagnosis should be included as a regular practice for active surveillance of the disease and its accomplishment before commencing an outbreak.
PURPOSE: Northeast Region of India possesses an abundant number of Aedes mosquitoes, the common vector for Dengue and Chikungunya (CHIK). Dengue is reported every year from Assam, but active surveillance for CHIK virus (CHIKV) infection is lacking in this part of India. Therefore, this present study has been undertaken to detect any CHIKV infection during a dengue outbreak in Assam. MATERIALS AND METHODS: A total of 42 dengue negative samples collected from Guwahati were screened for the presence of CHIK IgM antibodies. Further, all the samples were processed for CHIKV RNA detection by reverse transcriptase-polymerase chain reaction (RT-PCR). Phylogenetic analysis was done by Maximum Likelihood method using Kimura-2 parameter model. RESULTS: No IgM positivity was found in the processed samples; however, 7 samples were positive for CHIKV by RT-PCR. Phylogenetic analysis revealed that the circulating CHIKV belonged to Eastern, Central and Southern African genotype. Sequence analysis showed two uniform nucleotide substitutions and very less amino acid substitution. CONCLUSION: Silent existence of CHIKV beside dengue is reported from this study. Therefore, CHIKV diagnosis should be included as a regular practice for active surveillance of the disease and its accomplishment before commencing an outbreak.
Authors: Parbati Phuyal; Isabelle Marie Kramer; Doris Klingelhöfer; Ulrich Kuch; Axel Madeburg; David A Groneberg; Edwin Wouters; Meghnath Dhimal; Ruth Müller Journal: Int J Environ Res Public Health Date: 2020-09-12 Impact factor: 3.390