It's a common misconception that only 1% of bacteria cause disease. The truth is that we don't know the exact percentage of bacteria that cause disease, and the reality is much more nuanced.

Here's why:

* We haven't identified all bacteria: The vast majority of bacteria haven't been fully studied or even identified. It's impossible to say whether they are pathogenic (disease-causing) or not without proper research.

* Bacteria can be opportunistic: Many bacteria are considered commensal, meaning they live in our bodies without causing harm. However, these bacteria can become pathogenic under certain conditions like weakened immune systems or when they enter a new environment.

* Disease is a complex interaction: Disease isn't just caused by a single bacterium. It's a complex interplay of factors including the specific bacteria, the host's immune system, environmental conditions, and other factors.

* The "good" bacteria: Many bacteria are actually beneficial to our health. They help with digestion, produce vitamins, and protect us from harmful bacteria.

The bottom line: It's incorrect to say that only 1% of bacteria cause disease. While there are many bacteria that are harmless or even beneficial, there are also many that can cause disease under certain circumstances. We still have much to learn about the vast world of bacteria, and it's important to remember that they are not all bad.