It is the public policy of this State that county engineers and superintendents of highways should not suffer pecuniary loss because of any injury to persons or property resulting from their failure to perform or negligence in performing any official duty and which injury arises out of the use of highways, culverts, bridges, or shoulders for which they have some degree of supervisory, maintenance, repair or construction responsibility and that persons who suffer such injury should not be entirely precluded from recovery of loss occasioned by any such injury.