The Ministry of Business, Innovation and Employment has useful resources here covering lots of issues about how employers should deal with the virus, from questions about sick leave to understanding your duty of care in the workplace. Retail NZ has put together a handy summary of this.
The Privacy Commissioner has answered employment-related privacy issues here.
If you are in the position of needing to consider redundancies, you can find additional support here. It is vital that you follow the correct procedures.