1

I'm not sure what you mean by "no obligations" but South Africa and Tanzania do mandate yellow fever immunization of certain travelers. South Africa is particularly strict in enforcing this. Malaria occurs throughout Madagascar, in most of Tanzania, and in parts of South Africa.

If you go here you can see the US CDC recommendations for immunizations and malaria prevention for each country.

The US has no immunization requirements for residents or visitors.

2

Heed Nutrax's wise words ...

However, also bear in mind we've lost TT members to malaria who didn't take anything ...

You have one life, don't risk it

Kira

3

Yellow fever is necessary, sometimes you get asked for your certificate and if you don't, you could also pay to get it right at the border - in some room by a "nurse". Seen it happen before, it is legitimate , you get a certificate, way cheaper than getting it at home. Having said that, you might not be asked for the certificate. It is a gamble. Wouldn't go without getting a typhoid shot though.
As for malaria, lots of people who spend months there don't take the pills, it is possible for you, but you need to be cautious about getting bitten and the instant you have any symptoms, whether you think you we're bitten or not, you go get blood work done ASAP. It is an easy quick blood test and the meds are available everywhere and cheap. If you don't re ognize your symptoms, that's it could be fatal.

4

It is a quick blood test, IF you can find a clinic nearby & understand the symptoms, if not, it can kill in 48hrs

Kira