  Recent theoretical and observational studies debate the similarities between
the formation process of high-mass (>8 Msun) and low-mass stars. The formation
of low-mass star formation is directly associated with the presence of disks
and jets. According to this scenario, radio jets are expected to be common in
high-mass star-forming regions. We aim to increase the number of known radio
jets in high-mass star forming regions by searching for radio jet candidates at
radio continuum wavelengths. We have used the Karl G. Jansky Very Large Array
(VLA) to observe 18 high-mass star-forming regions in the C band (6 cm, ~1.0
arcsec resolution) and K band (1.3 cm, ~0.3 arcsec resolution). We have
searched for radio jet candidates by studying the association of radio
continuum sources with shock activity signposts. We have identified 7 as the
most probable radio jets. The radio luminosity of the radio jet candidates is
correlated with the bolometric luminosity and the outflow momentum rate. About
7-36% of the radio jet candidates are associated with non-thermal emission. The
radio jet candidates associated with 6.7 GHz CH3OH maser emission are
preferentially thermal winds and jets, while a considerable fraction of radio
jet candidates associated with H2O masers show non-thermal emission, likely due
to strong shocks. Our sample of 18 regions is divided in 8 less evolved,
infrared-dark regions and 10 more evolved, infrared-bright regions. We have
found that ~71% of the identified radio jet candidates are located in the more
evolved regions. Similarly, 25% of the less evolved regions harbor one of the
most probable radio jets, while up to 50% of the more evolved regions contain
one of these radio jet candidates. This suggests that the detection of radio
jets in high-mass star forming regions is larger in slightly more evolved
regions.
