What is one feature that CDC recommends for effective face masks?

The recommendation for multiple layers of fabric in face masks is grounded in the science of filtering respiratory droplets, which are the primary means of spreading viruses such as SARS-CoV-2, responsible for COVID-19. Multiple layers increase the effectiveness of the mask by providing additional barriers that can trap these droplets, thereby helping to protect both the wearer and others from potential transmission.

Masks with multiple layers can effectively filter both large and small particles, optimizing protection. The layers work together to create a more effective barrier against the penetration of airborne pathogens. This design not only enhances the mask's ability to block respiratory emissions during normal speech, sneezing, or coughing but also improves breathability compared to single-layer masks.

In contrast, features such as a stylish design or being disposable may not contribute directly to the mask's effectiveness in preventing virus transmission, while a single layer of fabric could reduce protection significantly by allowing more particles to pass through. Therefore, the emphasis on multiple layers is a key aspect of public health guidelines for effective mask-wearing during respiratory disease outbreaks.