Zika virus: Current concerns in India

With confirmation of Zika virus (ZIKV) presence in India, screening of a large number of febrile illness samples yielded only four positive cases. In this review, we address the current concern with context to India. The possible reasons for low level of Zika prevalence in India have been discussed, by extracting some probable explanations from previous experience of chikungunya virus-vector model/studies. In the current context, it is hypothesized that Indian mosquito strains have lower susceptibility gradient/threshold for ZIKV. The very low positivity in the humans also indicates low levels of mosquito-human-mosquito transmission cycle. There is also a need to look for the existence of any such animal cycle/sylvatic involvement in India. The recently detected four cases in India show local transmission of ZIKV suggesting that ZIKV might have been present in India since long time. The earlier vector-virus relationship studies with chikungunya suggested that in due course of time, ZIKV might become a major public health concern in the future.