WhatsApp says it has seen a drop of 70% in "highly forwarded" messages - the kind that may spread misinformation about the coronavirus.
The World Health Organization has said the spread of fake news about the outbreak is an "info-demic".
And two weeks ago, WhatsApp stopped messages sent between individual users five times or more then being posted to more than one chat group at a time.
But experts say it still has more to do in the battle against misinformation.
“WhatsApp is committed to doing our part in tackling viral messages," a spokesman for the messaging platform said.
"This change is helping keep WhatsApp a place for personal and private conversations."