Final answer:
Cater Cleaning Centres should continue thorough cleaning of their air conditioning systems and uphold their regular maintenance program to prevent biofilm growth. Reviewing practices at all facilities is also key to maintaining hygiene and safety standards.
Step-by-step explanation:
My recommendation for Cater Cleaning Centres in the aftermath of the infections would be to remain vigilant and make sure that the comprehensive cleaning of the air conditioning system is thorough and reaches all parts where biofilms could develop. It's excellent that they have initiated a regular maintenance program; consistent upkeep is key to preventing future issues. Furthermore, the review of practices at other facilities is a crucial step in ensuring that a high standard of hygiene and safety is maintained across the board.