According to the National Rosacea Society, this common yet poorly understood skin condition affects more than 16 million Americans — and this doesn’t include those with undiagnosed flushing and persistent redness. Rosacea is the subject of much dermatological research, and if you have it, you just may have a reason to celebrate.

Countless studies are looking at the causes of rosacea in an effort to discover new ways to treat it. (You can view the trials that are currently under way at clinicaltrials.gov.) Based on recent findings, rosacea may be more complex that previously believed. There seem to be four distinct types of rosacea — and the new drugs being developed represent new ways to treat these four types.

One especially interesting and important finding is that the skin plays host to many more types of organisms than previously thought. Genetic research has found previously undiscovered bacteria that are unable to grow in culture dishes, and it’s believed these newly discovered organisms play a role in rosacea.

The four types of rosacea include:

•  Flushing: Redness is caused by dilated blood vessels. New drugs are being researched to prevent the dilation.

•  Papular or acne-like rosacea: This type includes skin redness along with overlying red bumps in the center of the face that are often mistaken for acne. These bumps may be caused by organisms on the skin such as demodex (a particular type of mite) or by organisms that have not yet been identified.

•  Broken blood vessels: Visible broken blood vessels are likely caused by years of dilating and constricting. At this time, laser and other light-based treatments are the most effective.

•  Growth on the nose known as rhynophyma: Doctors still have no idea why this occurs and what its relationship is to rosacea, but it is found in people with a history of rosacea. Laser surgery is the treatment of choice.

There has been much progress in rosacea research in recent years, and the identification of these distinct types of rosacea represents a major step forward. If new drugs designed to address these different types of rosacea are effective, that’s great news for the millions of people suffering from this skin condition. In the meantime, if you have any of the rosacea symptoms listed above, see your dermatologist. And stay tuned for more rosacea updates as they are available.

Dr. Leslie Baumann is a board-certified dermatologist and the CEO of the Baumann Cosmetic & Research Institute in Miami Beach.