0) You could learn about Malaria and how to avoid catching it from the internet. <- and still go out and drink from your only water supply, full of feces and god knows what else.
Presumably one of the things you could find on the internet if information about how to improve your only water source. Although I expect most parts of the world figured out it not a good idea for your privy to run into your well before the English did.
1) You could use the internet to ask for medical assistance. <-Or approach the medical staff who have medicines with them, backed by international health organisations
I expect if International Health staff were just standing around the village with nothing to do, the first thing they would have done is improved that well we just finished discussing. In reality you probably have to hunt them down. So tell me, which is easier, having the family living on $1/month hunt down the medical staff backed by the billionaire, or having them send notice to the medical staff to come to the village or arrange a meeting at another location?
3) You could use the internet to discover how to treat malaria and acquire appropriate treatments. <-what, using paypal accounts full of sand?
Some of the stuff you can do to prevent it is no or very low cost. The internet certainly provides better chance to connect to organizations that assist with the expensive bits. Hell, put the a decent plan together and you might even be able to crowd source it. We 'Merkins take a lot of flack for not properly funding international organizations that governments create to handle these things. But what I've noticed is that if you go to a local church with a specific plan to help a specific location with a well thought out project, they'll cough up the money for it. Sometimes as quick as a week, sometimes longer depending on the size of the project.