A government-commissioned review has found that there are "worryingly low" numbers of staff with up-to-date training in child protection.
Regulators who surveyed 392 NHS trusts on behalf of the government said the figure of 54% was "worryingly low".
The Care Quality Commission (CQC) report revealed around 65% of GPs either do not have appropriate training or do not have the data to prove it, despite around one in 10 GP consultations in 2007/08 being with children aged 14 or under.
GPs were also identified by the review as lacking appropriate training, with 65% not having the training or there being no record of them having it or not.
It also found that of A&E and urgent care staff, only 58% had the correct child protection training - around three million children under 16 attend A&E ever year.
The recommendation is that primary care trusts should have caseloads of no more than 400 children per health visitor. But the new study found that 29 out of 152 trusts reported caseloads of more than 500 children.
"From my experience, it depends on the type of trust you are attached to. As a student nurse on critical care placement, i had a chance of attending a course on my previous placement on child protection, and this course was very good because it gave me an insight into child protection issues, some of which i was not aware. So it should be made mandatory for all healthcare professionals, because during our interaction with patients, we are likely to meet children." - Aurelia, Glasgow
"Sadly child protection and safeguarding is often sidelined and training needs ignored" - Kathy French