You must follow the Health Ministry’s directives. From a halachic perspective, we are required both to follow the rules of government authorities and to protect public health.

A woman who has been ordered to quarantine herself is absolutely prohibited from leaving her home, except in situations in which it is medically necessary. Even then, she must inform the medical authorities. Additionally, family members are forbidden from coming close to her, and any physical contact is prohibited, even when the couple are halachically permitted to each other.

Immersion of a woman who is potentially a carrier of the Coronavirus could endanger the health of other women immersing in the mikveh, particularly those who are at high risk.

For these reasons, you must adhere to all instructions from the Ministry of Health, and not to permit immersion of any woman who has been instructed to enter quarantine.

If someone seeks your advice, you can explain the importance of strict adherence to the rules. A woman in this situation should finish her seven clean days as planned, and then wait until the quarantine period finishes to immerse. After counting the clean days, she need not perform any more bedikot, and should switch to colored undergarments.