According to the Centers for Disease Control and Prevention (CDC), the flu caused U.S. employees to miss approximately 17 million workdays. The result is an estimated $7 billion a year in sick time and lost productivity.

Cleaning teams can't afford to lose staff to a temporary illness. Here is some advice on how to help staff protect themselves:

The CDC reports that although nasal spray flu vaccine was not recommended last year, it will be for the 2018-2019 season. This nasal vaccination is approved for the use of non-pregnant individuals, and 2 years through 49 years of age. The CDC also recommends that people get a flu vaccine by the end of October.

Experts report that getting the flu vaccine is the No. 1 way to prevent the flu. While it is not possible to predict what this flu season will be like, the severity of last year’s has encouraged people to be more vigilant.

Influenza activity often begins to increase in October and November. Most of the time, flu activity peaks between December and February, and it can last as late as May, according to an article on the Daily Toreador website.

Health experts encourage anyone who has fever to stay home and visit a doctor. Flu can also be treated with over-the-counter medications. It can also be used preventatively for people who are in regular contact with the flu sufferer. In addition to rest and medications, preventative care such as strong hygiene can keep bacteria at bay.

Removing the flu virus from surfaces and the air in the workplace really can make a difference, according to an article on The Conversation website.

• Wiping down frequently touched surfaces such as doorknobs, tables, elevator buttons and faucets with alcohol-based cleaning products can make a difference.

• Increasing air circulation — by boosting the exchange rate of ventilation systems, or using ceiling or portable fans — can diffuse flu viruses and limit their spread.

• Air purifiers with HEPA filters and high flow rates designed to remove particles can also be effective in removing viruses from the air.