"Nothing is completely risk-free. But with just 44 published cases of potential inflight COVID-19 transmission among 1.2 billion travelers, the risk of contracting the virus on board appears to be in the same category as being struck by lightning,” said Alexandre de Juniac, IATA’s Director General and CEO.
IATA - Research Points to Low Risk for COVID-19 Transmission Inflight
Probably not the most unbiased source, but I'll leave it to others to analyse their methodology...