West Nile and Breastfeeding

For Everyone

What to know

  • Breastfeeding women infected with West Nile virus have a very low risk of transmitting the virus to their babies.
  • The benefits of breastfeeding outweigh the unknown risk of passing West Nile virus through breast milk.
A woman breastfeeds her baby while seated.

Can West Nile virus be transmitted through breast milk?

Possibly. It appears that West Nile virus may be transmitted through breast milk, although this is likely a rare occurrence.

In 2002, a woman developed encephalitis due to West Nile virus from a blood transfusion she received shortly after giving birth. Laboratory analysis showed evidence of West Nile virus in breast milk collected from the mother soon after she became ill. She had been breastfeeding her baby and about 3 weeks after birth the infant tested positive for West Nile virus. Because of the infant's minimal outdoor exposure, it is unlikely that infection was from a mosquito. The infant had no symptoms of West Nile virus infection and remained healthy.

Should I continue breastfeeding if I have West Nile?

Yes. The risk for West Nile virus transmission through breastfeeding is unknown. However, the health benefits of breastfeeding are well established. Therefore, there are no recommendations for a woman to stop breastfeeding because of West Nile virus disease (West Nile).

If I am breastfeeding, should I use insect repellents?

Yes. Protecting yourself from mosquito bites is the only way to prevent infection with West Nile virus. In addition to wearing protective clothing such as long-sleeve shirts and long pants, use insect repellents. Repellents containing active ingredients which have been registered with the EPA are considered safe for breastfeeding women. More information about insect repellents is available here.

Content Source
National Center for Emerging and Zoonotic Infectious Diseases (NCEZID)
About This Page
Published: May 15, 2024
Updated: May 15, 2024

This page was last updated on this date. Updates may include minor edits, image changes, or other modifications to page content.

Reviewed: October 23, 2026

The information on this page was last reviewed by subject matter experts to ensure accuracy.