Breast milk provides infants with nutrients and immune support, fostering their growth and development. Understanding the potential for certain infections to transmit through breast milk helps parents and caregivers make informed decisions about infant feeding.
Common Transmitted Infections
Several infections can pass from a mother to her infant through breast milk. Human Immunodeficiency Virus (HIV) is one such virus. For mothers with HIV, antiretroviral therapy (ART) can significantly reduce transmission risk to less than 1% if viral suppression is maintained. In resource-rich settings, formula feeding is recommended to eliminate transmission risk. In other contexts, breastfeeding with ART is considered due to its benefits.
Human T-lymphotropic Virus (HTLV), particularly HTLV-1, transmits primarily through breastfeeding. The risk increases with longer durations and higher viral loads in breast milk. Cytomegalovirus (CMV) is common in breast milk and can transmit to infants. While full-term infants often have asymptomatic infections, preterm infants face a higher risk of symptomatic disease.
Hepatitis B Virus (HBV) can transmit from mother to infant. Breastfeeding is safe if the infant receives Hepatitis B immune globulin (HBIG) and the first dose of the vaccine within 12 hours of birth, making transmission risk negligible. Hepatitis C Virus (HCV) transmission risk through breast milk is low. Breastfeeding is safe unless the mother has cracked or bleeding nipples, which could allow blood-to-blood transmission. In such cases, temporarily stop breastfeeding from the affected breast.
Herpes Simplex Virus (HSV) transmits through direct contact with active lesions on the breast or nipple, not through breast milk. If active lesions are present, temporarily stop breastfeeding from that side and discard expressed milk. Breastfeeding from the unaffected breast is safe if lesions are covered and proper hand hygiene is practiced.
Syphilis, caused by bacteria, can transmit if breast sores contact the infant or pumping equipment. If breast lesions are present, pump and discard milk from the affected breast until sores heal.
Tuberculosis (TB) is not transmitted through breast milk. However, close contact with an infected mother with active, untreated pulmonary TB poses an airborne transmission risk. Breastfeeding is encouraged for mothers on appropriate TB treatment, with precautions like wearing a mask if infectious.
Factors Influencing Transmission
Several factors influence the likelihood of infection transmission through breast milk. The mother’s viral load or disease activity significantly impacts transmission risk. For example, a higher viral load in HIV-positive mothers increases transmission chance, though ART can reduce this. Active lesions in conditions like HSV or syphilis also present a direct contact transmission risk.
The duration and exclusivity of breastfeeding also affect cumulative exposure. Longer breastfeeding periods can increase exposure risk to pathogens in breast milk, as seen with HTLV-1. Mixed feeding, where infants receive breast milk and other fluids or solids, has been associated with a higher HIV transmission risk compared to exclusive breastfeeding.
A mother’s overall health and immune status can influence pathogen shedding into breast milk. A compromised immune system might lead to higher viral or bacterial loads. Breast tissue integrity is another factor. Cracked nipples, mastitis, or breast abscesses can create pathways for infected blood or fluids to enter the milk, increasing transmission risk for pathogens like Hepatitis C or Syphilis.
The infant’s health and gestational age affect their susceptibility to infection. Premature or immunocompromised infants are more vulnerable to infections passed through breast milk, as their immune systems are less developed. This is relevant for CMV, where preterm infants are at greater risk of symptomatic disease if infected postnatally.
Protecting Infant Health
Minimizing infection transmission risk through breast milk involves several practical steps. Maternal screening and testing for infections like HIV, Hepatitis B, Hepatitis C, and Syphilis are important during prenatal care. Early identification allows healthcare providers to implement interventions that reduce transmission risks.
For HIV-positive mothers, adherence to antiretroviral therapy (ART) is key for prevention. ART significantly lowers the maternal viral load, reducing HIV transmission risk. This allows for informed discussions about breastfeeding options based on individual circumstances and viral suppression.
Infant prophylaxis and vaccination are also important. Infants born to mothers with Hepatitis B receive Hepatitis B immune globulin and the vaccine at birth. This provides immediate and long-term protection, making breastfeeding safe even if the mother carries the virus.
In specific situations, temporary cessation of breastfeeding or pumping and discarding milk may be necessary. This applies when active lesions are present on the breast, such as with Herpes Simplex Virus or Syphilis, to prevent direct contact transmission. Maintaining milk supply by pumping during these periods is important.
Open communication between mothers and their healthcare providers is essential. Discussing individual health status and infant feeding plans ensures personalized advice to manage potential risks and optimize infant health.
Balancing Risks and Benefits
While disease transmission through breast milk is possible, the overall context is important. For many infections, transmission risk is low, especially with appropriate medical management and preventive measures. This includes maternal treatments and infant immunizations.
Breastfeeding provides many benefits for infant health. Breast milk delivers essential nutrition, supports immune system development, and offers protection against common illnesses. It also contributes to healthy growth and development.
Mothers should make informed decisions about infant feeding in consultation with their healthcare providers. This involves weighing specific transmission risks based on their health status against breastfeeding’s benefits for both mother and child. Seeking medical advice ensures personalized decisions based on current scientific understanding.