Infections, viruses released into the environment could be significant pandemic triggers, finds study

A study that looked at whether a virus can trigger a pandemic in a species not previously exposed to it has found that the fraction of the species population that gets infected and the virus' ability to multiply and release copies of itself into the environment could be particularly significant.

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Among the multiple theories around how the COVID-19 pandemic got triggered is one that concerns a 'spillover' of the disease-causing virus from a bat to humans via an intermediate species.