I better interject here since I feel there are some misconceptions on public health.
The first point made was that since biomedical research medical research has more funding it is considered important. Importance has nothing to do with funding. The largest reason why biomedical research has more NIH funding is because it generates money while public health interventions don't. For instance, making a vaccine generates money for the health industry (since the people themselves are paying for it). However, telling people to exercise/diet to stave off heart disease and diabetes doesn't generate money. It does however saves money in the long run, but people don't realize this (i.e. less dudes coming into the ER with a MI or heart failure => less costs for insurance companies and people and, yes, hospitals). The benefits of biomedical interventions can also be seen, such a drug therapy or surgical procedures. However, public health interventions are not nearly as visible, such a keeping water clean, proper sanitation, etc. (we even take it for granted, until its gone that is).
The second point made is that without an understanding of microorganisms there is no way public intervention against them could be done. Yes, it does help to know what we are up against and basic science discoveries have been pivotal against pandemics such as small pox. However, I can think of one famous example that counters this statement. You all remember Dr. John Snow, the founder of epidemiology. He was trying to figure out the cause of death of people with digestive problems in London. He surveyed the people and pin pointed the problem to a water pump in town. Had the water pump removed and the deaths due to the unknown disease dropped. This disease was, of course, Cholera but the best part was that he didn't even know it was a bacterium at all. A public health health intervention that was done without the understanding of the microorganism that caused it.
Even till this day when there is outbreak of a disease that is unknown, public health officials still try figure out ways to stop the spread of the disease even with minimal understanding of the pathogen (covering the mouth, or washing ones hands, etc.). It doesn't always follow the linear pattern of find out pathogen => figure out route of transmission => figure out public health measures.
Last point made is that it doesn't help for specialty specific research. This is true for the most part and it is always good to have research in the field. However, it won't be wise to brush it off entirely. There are still specialties in medicine that rely on such research such as preventative medicine or occupational medicine (requiring an MPH). So if one wanted to enter the field for residency (even in IM, FM, or Peds) or as a fellowship it could help having a publication in pubic health. I have heard many cases of SDN members doing public health research on the forum and wondering if it worth their while. Most members have said if it generates a pub then yes.