  We report the validation of a recently proposed infrared selection criterion
for symbiotic stars (SySts). Spectroscopic data were obtained for seven
candidates, selected from the SySt candidates of Akras et al. (2019, MNRAS,
483, 5077) by employing the new supplementary infrared selection criterion for
SySts in the VST/OmegaCAM Photometric H-Alpha Survey (VPHAS+). Five of them
turned out to be genuine SySts after the detection of H$\alpha$, He II and [O
III] emission lines as well as TiO molecular bands. The characteristic O VI
Raman-scattered line is also detected in one of these SySts. According to their
infrared colours and optical spectra, all five newly discovered SySts are
classified as S-type. The high rate of true SySts detections of this work
demonstrates that the combination of the H$\alpha$-emission and the new
infrared criterion improves the selection of target lists for follow-up
observations by minimizing the number of contaminants and optimizing the
observing time.
