Breasts and udders contain mammary glands. They are subject to a number of diseases and conditions. Some of these diseases include but not limited to abnormal nipple conditions, fibrocystic breast changes, infections and inflammations, and neoplasms.
There are certain diseases and conditions that occur or cause complications mostly during pregnancy and postpartum. For example, sore breasts, breast enlargement, breast engorgement, plugged milk ducts, cracked or bleeding nipples, inverted or flat nipples, fungal infection (e.g., yeast infection or thrush), and breast infection. Breast engorgement is the painful overfilling of breasts with milk caused by an imbalance between milk supply and infant or milking demand. It occurs in the mammary glands due to expansion and pressure by the synthesis and storage of breast milk, which happens when the breast switches from colostrum to mature milk or when breastfeeding or other expression of milk is not sufficiently frequent. Engorged breasts or udders may swell, throb and cause mild to extreme pain. Engorgement may result in a plugged milk ducts and/or infection.
A plug in the milk duct can form when milk becomes static, thickens or dries out. The formation of a plug makes it more difficult to release the milk causing more pain. If left untreated, a plugged duct may become infected, resulting in mastitis or abscess.
Mastitis is a common occurrence among breastfeeding women and among dairy animals. Reduced milk flow, e.g., due to plugged milk ducts, tends to render a subject to be more susceptible to infection. Mastitis is caused by bacteria that enter the breast through small cracks in the nipple or the udder through the teats. Upon entering, bacteria can multiply in the fatty tissue surrounding the milk ducts causing swelling, warmth, or pain. In the most severe infections, an abscess may develop, which needs to be drained by an office procedure or with surgery. The World Health Organization (WHO) estimates that the prevalence globally of mastitis is approximately 10% of breastfeeding women. A US-based study showed that as many as 33% of breastfeeding women developed mastitis (Riordan, J. M., and F. H. Nichols: A descriptive study of lactation mastitis in long-term breastfeeding women. Journal of Human Lactation, 6(2):53-58 (1990)). Studies also suggest that women with a history of mastitis have a higher incidence rate of breast cancer (Lambe et al., Epidemiology 20(5):747-51 (2009)). Most women that develop breast infections usually do so within the first few weeks after delivery or at the time of weaning. Women with diabetes, chronic illness, AIDS, or an impaired immune system may be more susceptible to the development of mastitis. Symptoms associated with breast infection or mastitis include, but are not limited to, breast enlargement, breast tenderness or warmth to the touch, breast lump and hardened breast, pain or a burning sensation continuously or while breast-feeding, itching, nipple discharge, nipple sensation changes, swelling of the breast, skin redness, and fever.
Women including breastfeeding women are also subject to fungal or yeast infection (thrush) which may cause the woman to feel severe stinging or burning pain on the surface of the nipples or deep inside the breast. The nipples may be itchy and appear puffy, scaly, flaky, weepy, or have tiny blisters. Alternatively, nipples may appear completely normal, but be severely painful.
Conventional treatments for the conditions and diseases described above include placing moist and warm packs at the place of infection over the breast, taking a warm shower before breastfeeding, applying a cold press to reduce pain and swelling, taking antibiotic medications for the infection, and draining of abscesses. For fungal infection, the treatments include rinsing nipples with a solution of water plus an acid such as vinegar after nursing and then air drying; applying antifungal creams; numbing nipples with cold substance such as ice wrapped in washcloth; and taking pain relieving medications.
However, these methods are not convenient or comfortable for most subjects. For example, placing warm moist towel over breasts may introduce more bacteria and rinsing nipples with a solution after every nursing event is not convenient. Taking a warm shower before every breastfeeding is not practical. The antibiotic approach requires a prescription and takes about 24 hours to work. The subject also has to take the medicine for 7 to 10 days before the symptoms are gone and such medications can enter the breast milk and enter the nursing infant or milk supply.
Mastitis can also occur in other mammals such as cows, goats, ewes, does, mares and sows. In fact, mastitis is one of the most significant diseases within the dairy industry. Even on well-managed farms, mastitis can occur in at least 33% of cows. It results in a considerable loss in profitability and, in extreme cases, in death of the dairy cow. Mastitis in dairy animals can occur in either a clinical or subclinical state. Dairy animals that develop clinical or subclinical mastitis are less productive and at greater risk for future mastitis. Symptoms of clinical mastitis include abnormal milk production, swollen udders, and elevated body temperature. Subclinical mastitis is the most common form of mastitis in the dairy industry and detection is only possible through diagnostic or laboratory tests as the milk of dairy animals with subclinical mastitis appears normal. Detection of subclinical mastitis occurs through analysis of milk sample for somatic cell count (SCC) and/or bacteria. Dairy animals are usually considered to have subclinical mastitis when the SCC exceeds about 200,000 cells/ml. Subclinical mastitis has great economic consequence as udder infection results in long term reduction of milk yield. Conventional methods of prevention and treatment of mastitis of dairy animals includes reducing exposure of the dairy animal to the bacteria, enhancing the immune system of the animal, and antibiotics. However, such methods are difficult to implement and/or maintain. For example, antibiotics should be administered to infected animals for about 60 days and milk should be constantly monitored for the presence of elevated SCC and bacteria. Therefore, prevention of initial infection is important to the dairy industry.