There are private hospitals in Vientiane. One being Allianz which has good doctors and facilities. There are others too so find one which speaks English.
I suggest you Google private hospitals Vientiane for information. There is a list on the forum too.
The dust may be a problem as is mosquitoes.
Your accommodation should have screens on windows and doors and make sure there is no standing water around where the mosquitoes can breed.
Wear long sleeve shirts, trousers, especially around dusk as this is when mosquitoes come out.
There are lotions or sprays you can use too. Also electric zappers and coils which you light and the smoke discourages the mossies.
You should register with a hospital or doctor too.
Please feel free to post any questions here.
What school is you wife going to teach at?
The school may be of assistance with information too.