Lawrence RM. Circumstances when breastfeeding is contraindicated. Pediatr Clin
North Am. 2013 Feb;60(1):295-318.
“Local infections of the breast, mastitis or breast abscess, are not contraindications to continued breastfeeding. Antimicrobial therapy should be chosen with consideration of the most common organisms (penicillin-resistant Staphylococcus aureus, Streptococcus, Escherichia coli) and agents that are compatible with breastfeeding.  In most instances the infecting organism has not been identified unless a culture has been done. Possible factors predisposing to mastitis or milk stasis should be addressed and effective milk-removal strategies encouraged along with more frequent breastfeeding. Pumping and discarding the milk for a short period while optimizing continued effective milk removal has been recommended for invasive Group B Streptococcus infection in the mother or infant.  In most scenarios, appropriate empiric therapy has already been initiated for 1 to 2 days before culture results are available and no temporary interruption of breastfeeding or breast milk is indicated. As long as drainage from the abscess does not directly contact the infant’s mouth, continued breastfeeding from the affected breast is appropriate. ”
Dixon JM. Breast infection. BMJ. 2013 Dec 16;347:f3291.
“Infection is more frequent following a first child and most commonly seen within the first six weeks of breastfeeding, although some women develop it during weaning. Lactating infection presents with pain, swelling and tenderness. There is usually a history of a cracked nipple or skin abrasion, but this is not the site of entry of organisms. S aureus is the most common organism responsible, but S epidermidis and streptococci are occasionally isolated. Drainage of milk from the affected area is reduced. Promotion of milk drainage and early antibiotic therapy are the cornerstones of treatment. Tetracycline, ciprofloxacin and chloramphenicol should not be used to treat lactating breast infection as they may enter breast milk and can harm the baby.”
“During breastfeeding the baby can be infected by mother’s pathogens with several routes of transmission that can be considered, such as respiratory secretions and droplets (e.g. Adenovirus, Influenza virus, Respiratory Syncytial Virus, Haemophilus, Mycoplasma) direct contact with lesions in the breast and nipple (e.g. HSV 1-2, VZV, Treponema) and breast milk. Frequently, in case of infection, different routes of transmission are contemporary implicated. The basic assumption is that breastfeeding is rarely contraindicated during maternal infections, a few exceptions are HTVL-I and HIV in industrialized country. The theoretic risk for transmission trough breast milk should be discussed and balanced with the benefits of breast milk, so the mother and parents can make an informed decision concerning infant feeding.”
Lawrence RM, Lawrence RA. Breast milk and infection. Clin Perinatol. 2004
“In most maternal viral infections, breast milk is not an important mode of transmission, and continuation of breastfeeding is in the best interest of the infant and mother (see Tables 2 and 3). Maternal bacterial infections rarely are complicated by transmission of infection to their infants through breast milk. In a few situations, temporary cessation of breastfeeding or the avoidance of breast milk is appropriate for a limited time (24 hours for N gonorrheae, H infiuenzae, Group B streptococci, and staphylococci and longer for others including B burgdorferi, T pallidum, and M tuberculosis). In certain situations, prophylactic or empiric therapy may be advised for the infant (eg, T pallidum, M tuberculosis, H influenzae) (see Table 1). Antimicrobial use by the mother should not be a reason not to breastfeed. Alternative regimens that are compatible with breastfeeding can be chosen to treat the mother effectively. In most cases of suspected infection in the breastfeeding mother, the delay in seeking medical care and making the diagnosis means the infant has been ex-posed already. Stopping breastfeeding at this time only deprives the infant of the nutritional and potential immunologic benefits. Breastfeeding or the use of expressed breast milk, even if temporarily suspended, should be encouraged and supported. Decisions about breast milk and infection should balance the potential risk compared with the innumerable benefits of breast milk.”
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