Detection of Dengue Virus RNA in Breast Milk Following Peripartum Infection - Guangzhou City, Guangdong Province, China, 2024.

WHAT IS ALREADY KNOWN ABOUT THIS TOPIC?: Dengue fever is primarily transmitted by Aedes mosquitoes. While most cases are asymptomatic or mild, some may progress to severe complications. Laboratory diagnosis relies on detection of nucleic acid, antigen, or antibodies in blood specimens.

WHAT IS ADDED BY THIS REPORT?: A patient who developed dengue fever 1 day before delivery had dengue virus RNA, NS1 antigen, and IgM detected in breast milk within 10 days of symptom onset. Nucleic acid and NS1 turned negative by day 15, while IgM antibodies remained positive and turned negative by day 22, suggesting potential transmission risk via early breastfeeding.

WHAT ARE THE IMPLICATIONS FOR PUBLIC HEALTH PRACTICE?: Breastfeeding should be avoided until 22 days post-onset, after confirming clearance of viral RNA and IgM from breast milk and excluding infection in the infant. Household members of pregnant women exhibiting suspected dengue symptoms should seek immediate medical attention for dengue NS1 antigen testing during dengue season.