Funding for this research was provided by:
Indian Council of Medical Research (5/8/10-4 (Oto)/2010-NCD-I)
Received: 8 May 2018
Accepted: 17 December 2018
First Online: 3 January 2019
Ethics approval and consent to participate
: Ethics approval was granted by the Institutional Ethics Committee (IEC/ND/10/AUG/18/22) of Sri Ramachandra University. Since all participants were children under five years of age, written and verbal informed consent was obtained from parents. Consent forms were prepared in Tamil, the local language. The institutional ethics committee approved the consent form. If parents were not literate, the content of the consent form was read out to the parent. Upon verbal consent, parent’s either signed their name or placed their thumb print on the consent form. This process of obtaining informed consent from parents was approved by the institutional ethics committee.
: Written consent has been received from the individuals in Figs. InternalRef removed and InternalRef removed. Figure InternalRef removed is reproduced using resources from Wikimedia commons available in public domain.
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