Couple of things to be aware when traveling to Africa or Latin America.
1) Visa and passport requirements
Only the countries you plan to visit can provide up-to-date information about their visa requirements. For all countries, contact the nearest embassy or consulate of the country you intend to visit well in advance of travel.
http://protocol.dfat.gov.au/Default/view.rails
Some of the more frequent destinations Australians visit frequently are listed on the Smarttraveller website.
2) Vaccinations. It better be up-to-date for any preventive diseases.
These include but not limited to, Hep-A and B, tetanus-diptheria, thypoid, malaria, rabies etc.
Depending on the region you're traveling, consult the WHO (World Health Organization) for most up-to-date info on the appropriate travel medicine and plan 8 weeks in advance.
3) Be aware of pandemic diseases of places you're visiting (e.g yellow fever)
One of the most common question asked is:
How can I find out which countries require the yellow fever vaccine as a condition for entry?
A: The list of requirements by country is supplied by CDC (Centre of Diseases Control and Prevention). Otherwise you may run into issues when returning back to your origin.
4) Read the latest travel advisory - http://www.smartraveller.gov.au/
This site includes travel advice, esp politically unstable areas, ongoing threat level, overseas consular assistance such as contacts for embassies and consulates
