DAR ES SALAAM, June 5 -- WHEN reports of unusual illness began emerging in north-western Tanzania, health officials faced a familiar question: was it an isolated incident, or the start of something much bigger?

Within hours, laboratory tests confirmed the answer. The disease was Marburg virus, one of the worlds most dangerous infectious diseases.

For many public health experts, the speed of that diagnosis represented something much larger than a successful laboratory test. It demonstrated how far Tanzanias disease surveillance and response systems have evolved over the past two decades.

According to CDC Tanzania Country Director Dr Mahesh Swaminathan, the countrys ability to detect and respond to outbreaks today is dramatically stronge...