Readers of this blog will have read my comments about those occasions when we get virus infections that do not make us sick - so-called "asymptomatic" infections.It won't take a great leap of understanding then to see the potential for contact, droplet and aerosolized spread of such infections from a person who is suffering from vomiting and diarrhoea due to another cause.
In this instance, read the story Crawford Kilian posted on over-eating as a cause for hospitalisation during Ramadan. Given that we know respiratory viruses (it's a given that gastrointestinal viruses are!) can end up being shed through the intestine on occasion, and we know that viruses can reside and be transmitted through droplets and aerosol (which can remain suspended in a room for some time, with their tiny passengers remaining infectious), this could be an inadvertent cause of new infections, especially among healthcare workers but also other in- and outpatients visiting hospitals that may already be over-crowded.
With incubation times extending up to 12-days or so, these sites in the Persian Gulf States may see a spike in such infections in less than a fortnight.