Rosacea is a chronic condition of the skin that cause reddening of the skin and may cause swelling and skin sores that look like acne. This condition is frequently encountered in fair skinned women within an age range of 30-50 yrs although men when affected, may have more severe symptoms. Simple rosacea has been described as swelling of blood vessels underneath the skin of the face leading to the observed reddening, however, most of the time it is associated with secondary skin complications like acne, seborrhea and may be eye disorders like blepharitis. Patients with rosacea blush easily. They often feel a burning or stinging sensation in their face. To make things ugly, a lot of spider like veins may appear called telangiecstasia of the face. In worse situations, they additionally have acne like skin sores that may ooze or crust.
While this is medically described as 'not harmful', it is definitely embarrassing for the affected individual and particularly when there is no known cure for this condition. Health care practitioners have been treating these symptoms by recommending patients to avoid sun exposure, reduce stress, limit spicy foods and alcohol etc. They often prescribe antibiotics to prevent secondary infections that may aggravate the situation. However, up until now, there has not been any evidence that bacteria could be the causative agent of this condition. Antibiotics prescribed for rosacea, for example, tetracycline, minocycline or doxycycline, are believed to address the acne associated with rosacea. Physicians are of the opinion that rosacea is not acne and will not be cured by over the counter acne medications or antibiotics. Notwithstanding this fact, patients have observed significant improvement of their conditions when treated with antibiotics. Scientific explanation to this observation was lacking until recently, when a review article published from the National University of Ireland concluded that there could be a bacteria connection to the problem.
In the study, what they found is that, bacteria that live within tiny mites residing in the skin may function as a trigger to rosacea. This is the first time scientists have talked about a bacterial trigger to rosacea. Sun exposure, outdoor activity in hot weather, wind, hot bath, cold weather, specific skincare products and a lot of other ever-increasing list of factors have been traditionally considered as triggers for rosacea. However, there seemed to exist a disconnect between the observed improvement with antibiotic treatment and the believed absence of bacterial involvement as a cause of rosacea.
This recent paper in the Journal of Medical Microbiology (published August 30, 2012) summarizes findings that identify a mite species Demodex folliculorum, a normal fauna of the mammalian skin, to be harboring bacteria that might be responsible for causing symptoms of rosacea. These are parasitic mites commonly known as face mites and when present in large numbers can cause demodicosis. They normally reside near the hair follicles and their population density is greater near the cheeks, nose, eyebrows, eyelashes and forehead - areas mostly affected in rosacea. These mites are normally harmless however, one theory is that they contribute to hair loss. Their number increases as we age. Previous research has shown that persons with rosacea have more of these mites than normal individuals and the mites isolated from their skin harbor a species of bacteria identified as Bacillus oleronius. This finding, if true, may revolutionize treatment as this bacteria is found to be susceptible to some of the antibiotics used to treat rosacea. This probably explains why rosacea patients seemed to respond to antibiotics even though the conventional wisdom remained that bacteria is not the causative agent. Another bacteria, Staphylococcus epidermis has also been found from the pustules of the rosacea patients. While this research is promising and definitely going in the right direction to improve the prognosis of rosacea, more evidence will be needed to confirm that these bacteria are indeed the causative agents of rosacea and not coming from any secondary sources but from the face mites. Pharmaceutical companies are keeping a close eye on the current findings although, more publications in the same line of study are needed to confirm these initial observations. 
