There are two "lab source" scenarios that are being discussed that sometimes blend together.

The first is that virology research at the lab escaped into the population through infection of the researchers or, alternatively inappropriate disposal of test animals.

The second is that genetic engineering deliberately created a more dangerous virus.

The second scenario is obviously more serious and may amount to a charge of biological warfare. From evidence I've seen, the first is more likely. This subject heading "lab created" implies the second, but the article implies the first.