Before we had this machine, we'd see somebody in the clinic, then we'd have to see them on another day to collect a blood sample," said Dr Williams.
We had a system of motorcycle riders that went round all of our outreach sites on a particular day to collect samples. They would have to ride for four hours along a muddy road through the impenetrable Forest, to a laboratory on the other side, where we could get them tested.
It took us three days to get the result, and we couldn't get it back to the patient until we saw them again two weeks later.
Now, with this simple piece of technology, we can deal with problems immediately.
Now our death rates from HIV are very low We're able to diagnose it early, manage it early and keep people living with HIV fit and well," says Williams.