would this be good for unsafe drinking...
would this be good for unsafe drinking water in Nigeria?
The only problem is that this (and nearly all) filters are not effective against waterborne viruses, which may be of concern in untreated water in undeveloped countries. It would be a great first step, but you are probably well-advised to treat the water for viruses as well, after its been through the MiniWorks. A UV treatment or some sodium chloride drops/tablets would get you really in the clear.
This FILTER filters out many things including bacteria. But if you have things like virus in your water source, you would be better off buying a water PURIFIER which can be found sold alongside many FILTERS. They are somewhat more expensive but if you are in an area where the water in your environment is so contaminated; I would go for a PURIFIER instead of a mere FILTER.
http://www.rei.com/learn/expert-advice/water-treatment-backcountry.html This article will be very helpful in understanding the difference between filters and purifiers.