A month or two ago, there was a lot of press about the risks of pets sleeping in beds. It was in response to an article in the journal Emerging Infectious Diseases that didn’t put forth any new information, but summarized a few diseases that could potentially be transmitted by pets. Unfortunately, the relative risk of those diseases wasn’t really explored, and some media reports latched onto diseases like the plague, transmission of which can occur between pets and humans but the likelihood of this in most areas is essentially nil.
Anyway, an article at Scienceline.org has taken a more balanced approach towards the subject. One sentence perhaps say it best: "Many of those scare headlines, however, missed the main point of Chomel’s work: For most people, the risks are minimal, and there are easy ways to go about preventing pet-to-owner disease sharing."
I won’t go into details here, since you can read the article yourself, but a key component is that pet ownership is never no-risk, but is usually low-risk. Basic hygiene practices and common sense can reduce the risks further. The cost-benefit needs to be considered, and while we can never completely eliminate the "cost" aspect, the benefits of pet ownership certainly outweigh the costs in the vast majority of households.