It said its operations had not been impacted to date and its plans would be adapted "as this unprecedented situation evolves".
Prevention and precautionary steps included the compulsory use of face masks at areas including turnstiles and shaft conveyance, holding group meetings via teleconference where possible and stressing the urgency of self-isolation if displaying symptoms.
"COVID-19 can be managed and I strongly encourage employees and their families not to panic," Harmony CEO Peter Steenkamp said.
Numerous miners around the world are scaling back or suspending some operations as a precaution or in response to government restrictions designed to stem the pandemic.
Harmony said it was also collaborating with other mining companies on potential regionalisation and synergies, such as the possibility of pooling facilities for quarantine.
The country's resources minister Gwede Mantashe met with industry leaders at the Minerals Council South Africa's special board meeting this week, where a 10-point plan was developed to address the situation.
Council CEO Roger Baxter said it was a sign of a collaborative approach "that bodes well during these trying times".
"As a key pillar of South Africa's economy, both in its own right and as a customer and suppliers of other sectors, the industry is determined to keep its facilities in operation in order to ensure that, once the COVID-19 pandemic has passed, South Africa's economy is able to resume, develop and grow," he said.
In another tough day on equities markets, Harmony's shares lost 8.8% yesterday to 4,100c, a midpoint in its 52-week range and capitalising it at ZAR22.25 billion (US$1.3 billion).