Principals from 10 schools in the area took the decision to close early on Thursday, after being notified by the Msunduzi Municipality that the fumes could toxic.
The fire broke out at the New England Road Landfill dumping site, and firefighters have been fighting since then to keep it contained.
Msunduzi Municipality spokesperson Siyabonga Hlongwa told The Citizen it would about three days to completely douse the fire.
“The cause of the fire is unknown. It is currently impossible to give estimates of the damage caused, but we can confirm that currently no lives have been lost,” Hlongwa said.