This is wildly inaccurate.

The data cited in that ABC article, published in 2008, is taken from the 2006-2007 flu season. Over the last 14 years, much has changed.

For example, in 2019-2020, over 80% of healthcare workers received the flu vaccine, including over 90% of those who work in hospitals.

Source: CDC https://www.cdc.gov/flu/professionals/healthcareworkers.htm