It is ok to get all of the vaccines at one visit. The meningitis and Yellow fever are one shot each. The Hepatitis A vaccine requires three shots for full immunity at intervals of 0, two months later, four months later. Depending on your departure date, it would be good to receive as many of the Hep A shots as possible before leaving, and then complete the series when you return. It's also good to make sure your Tetanus (Tdap) and Measles (MMR) vaccinations are up to date.