It is a widespread belief that antibiotics should not be used for treating viral infections, as they are effective against bacteria, not viruses (see e.g. http://www.cdc.gov/features/getsmart/). Several studies have been made supporting this claim, for instance this 1984 study and newer 2014 review.
However, antibiotics continue to be prescribed, mostly due to patient demand, and also because of fear of complications (FoxNews article). In case of respiratory viral infections secondary bacterial pneumonia is often mentioned as a cause of concern and a reason for antibiotics prescription (2006 study).
Also, this article states that
Around one person in 20 with bronchitis may develop a secondary infection in the lungs leading to pneumonia. The infection is commonly bacterial although the initial infection that caused the bronchitis may be viral.
Some studies also say that certain classes of antibiotics (e.g. macrolides) have positive anti-inflammatory and immunomodulatory effects (2012 study).
What I'm confused about is this: in case when there are no secondary bacterial infection symptoms, is antibiotics usage justified? Does the risk of secondary infection outweigh the negative effects of antibiotics?