A novel 2006 Indian outbreak strain of Chikungunya virus exhibits different pattern of infection as compared to prototype strain.
BACKGROUND
The recent re-emergence of Chikungunya virus (CHIKV) in India after 32 years and its worldwide epidemics with unprecedented magnitude raised a great public health concern.


RESULTS
In this study, a biological comparison was carried out between a novel 2006 Indian CHIKV outbreak strain, DRDE-06 and the prototype strain S-27 in mammalian cells in order to understand their differential infection pattern. Results showed that S-27 produced maximum number of progenies (2.43E+06 PFU/ml) at 20 to 24 hours post infection whereas DRDE-06 produced more than double number of progenies around 8 hours post infection in mammalian cells. Moreover, the observation of cytopathic effect, detection of viral proteins and viral proliferation assay confirmed the remarkably faster and significantly higher replication efficiency of DRDE-06. Moreover, our mutational analysis of whole genome of DRDE-06 revealed the presence of nineteen mutations as compared to S-27, whereas the analysis of 273 global isolates showed the consistent presence of fifteen out of nineteen mutations in almost all outbreak isolates. Further analysis revealed that ∼46% of recent outbreak strains including DRDE-06 do not contain the E1-A226V mutation which was earlier shown to be associated with the adaptation of CHIKV in a new vector species, Aedes albopictus.


CONCLUSIONS
A novel 2006 Indian CHIKV outbreak strain, DRDE-06 exhibits different pattern of infection as compared to prototype strain, S-27. This might be associated to some specific mutations observed in genome wide mutational analysis in DRDE-06 which emphasizes the need of future experimental investigation.
Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, Odisha, India.
Abhishek
A
Kumar
Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, Odisha, India.
Prabhudutta
P
Mamidi
Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, Odisha, India.
Indrani
I
Das
School of Biological Sciences, National Institute of Science Education & Research, Bhubaneswar, Odisha, India.
Tapas K
TK
Nayak
Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, Odisha, India.
Sameer
S
Kumar
Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, Odisha, India.
Jagamohan
J
Chhatai
School of Biological Sciences, National Institute of Science Education & Research, Bhubaneswar, Odisha, India.
Subhasis
S
Chattopadhyay
Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, Odisha, India.
Amol R
AR
Suryawanshi
Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, Odisha, India.
Soma
S
Chattopadhyay
D000818:Animals; D065632:Chikungunya Fever / Q000453:epidemiology / Q000821:virology*; D002646:Chikungunya virus / Q000235:genetics / Q000472:pathogenicity*; D002522:Chlorocebus aethiops; D004196:Disease Outbreaks; D006801:Humans; D007194:India / Q000453:epidemiology; D009154:Mutation; D010641:Phenotype; D012367:RNA, Viral / Q000235:genetics; D014709:Vero Cells
D012367:RNA, Viral