Influenza (the flu) is a contagious respiratory illness caused by influenza A or B viruses, with symptoms often including fever, body aches, fatigue, and a cough. New parents commonly worry if this illness requires them to stop feeding their infant. Health organizations strongly recommend continuing to breastfeed even when sick with the flu because it is safe and provides unique immune benefits to the baby.
Continuing to Nurse is Safe and Recommended
Breastfeeding can continue because the influenza virus is not transmitted through the milk itself. The virus spreads mainly through respiratory droplets released when a sick person coughs, sneezes, or talks, or indirectly from contaminated surfaces. Stopping nursing due to a flu diagnosis is almost never necessary and can be detrimental to the parent’s milk supply and the baby’s health. Breast milk remains the most complete form of nutrition and hydration for the infant. If the parent feels too unwell to physically hold the baby at the breast, they should express milk so a healthy caregiver can feed the infant.
How Breast Milk Protects the Infant
Breast milk actively protects the infant by transferring the parent’s immune response directly to the baby. When the parent is exposed to the flu virus, their immune system produces specific antibodies targeted to that strain, which are then passed through the milk.
The most prominent transferred antibody is Secretory Immunoglobulin A (sIgA). This sIgA coats the baby’s mucosal linings in the nose, throat, and gut, neutralizing the flu virus before it can infect the baby’s cells. This process of passive immunity means the baby receives protection without needing to mount a full immune response.
This immediate transfer of tailored antibodies can prevent the infant from getting sick or significantly lessen the severity and duration of symptoms. Since infants are at a higher risk of developing severe flu-related complications, continuing to nurse ensures the baby receives a constant supply of these strain-specific immune factors.
Essential Hygiene Practices While Sick
Since the flu virus is spread via droplets, rigorous hygiene protocols are necessary to prevent respiratory transmission to the infant. Meticulous handwashing with soap and water for at least 20 seconds is the most important step before touching the baby, baby items, or breast pump parts. If soap and water are unavailable, an alcohol-based hand sanitizer is an acceptable alternative.
The parent should wear a well-fitting face mask covering the nose and mouth during all close contact, especially while nursing or holding the baby. This barrier helps contain virus-containing droplets. Coughs or sneezes should always be directed into a tissue, which must be disposed of immediately.
The sick parent should also routinely clean and disinfect high-touch surfaces, such as doorknobs and countertops. If the parent is too weak or fatigued to safely hold the baby for a direct feeding, they should express their milk. A healthy adult can then feed the baby this milk, ensuring the infant continues to receive immune benefits while limiting exposure to the sick parent’s respiratory droplets.
Safety of Common Flu Medications
Most over-the-counter pain relievers and fever reducers used for flu symptoms are compatible with nursing. Medications like acetaminophen and ibuprofen are considered safe for use while breastfeeding and are often recommended to manage body aches and fever. These drugs pass into milk in small, clinically insignificant amounts.
Decongestants containing pseudoephedrine require caution. While the small amount that transfers into breast milk is not harmful to the infant, a significant concern is its potential to decrease milk supply. Studies indicate that a single dose of pseudoephedrine can reduce milk production by an average of 24% in some mothers.
For congestion relief, saline nasal sprays are preferable as they act locally and do not affect the milk supply or transfer to the infant. Prescription antiviral medications, such as oseltamivir (Tamiflu), are generally considered safe and compatible with breastfeeding. Minimal amounts of oseltamivir transfer into breast milk (less than 0.5% of the maternal dose) and are not expected to cause adverse effects.
Always consult a healthcare provider, pharmacist, or lactation specialist before starting any new medication to confirm its compatibility with breastfeeding, often referencing trusted resources like the LactMed database.