You can get an idea of that by looking at the distribution for the bacteria in question.
The distribution can be accessed either by:
1. Clicking on the distribution tab (for the bacteria we focus on) or
2. On the boxplot chart available under the breakdown or advanced sections
In the chart above, we can see that the 25th, 50th and 75th percentiles are all zero, therefore we know that at least 75% of samples do not contain this bacteria. You can form similar conclusions from looking at the other bacteria distribution. We will make it easier to see this by adding a prevalence percentage in Biomesight in the coming months.