Fig. 1

a Cassette where the sequence of clinical isolates, were cloned. Agarose gel electrophoresis of RT-PCR products from two positive patients (#137 and #178). Lane 1: molecular weight ladder; Lanes 2 and 3: positive bands corresponding to CHIKV (1032 bp) amplified fragments, (patients #137 and #178), respectively. b Phylogenetic tree of CHIKV strains, based on the alignment of 1032 bp of the nucleotide sequence from the structural E-2 protein nucleotide sequence. Each strain is designated by its GenBank accession number followed by country of origin. The Yucatan HOH strain is identical to those previously reported in Yucatan during the same year and has a 100% identity to the strain isolated in Chiapas, Mexico in 2014. c Comparative protein sequence of CHIKV cloned