Thanks for staying online.I’ve taken a close look at your question & the reply and come up with the following answer:
Most vomiting is caused by a viral infection.These infections often don't last long.Also there can be a possibility of re-infection.Stop giving him solid diet.Let the child's stomach rest for 1 hour after vomiting, then give sips of liquids every 10 to 15 minutes.Gradually increase the amount of liquid you offer. Another possibility of his symptoms can be due to a condition called Cyclic vomiting syndrome (CVS).CVS is characterized by episodes or cycles of severe nausea and vomiting that last for hours, or even days, that alternate with intervals with no symptoms.
Most probably the cause of his symptoms seems to be either re-infection of stomach flu or the previous infection was not completely cured & some of the virus left intact which then grow back & cause the symptoms.Also as you have told that you have just moved country this week,so viral infection(repeat stomach flu) seems to be the most probable cause. He needs following tests:
-Culture & sensitivity test of vomitus(material expelled out in vomiting)
-Other blood tests
Exact diagnosis can only be made after physical & clinical examination.So I advice you to make an appointment for him with pediatrician for these tests & examination to know the exact cause & then treatment will be done accordingly.