Public health officials in California warned parents about acquiring unpasteurized breast milk through social media channels after multiple infants were potentially exposed to HIV from an informal donor. According to a case report published in the Morbidity and Mortality Weekly Report by Akanksha Vaidya, MD, MPH, of the Santa Clara Public Health Department, and colleagues, five infants were identified as potential recipients of milk from a donor who later tested positive for the virus, though all exposed babies ultimately tested negative.
Investigation Details and Social Media Outreach
The public health investigation began in early October 2025 when the Santa Clara Public Health Department learned of a pregnant woman who received a positive HIV test result during a routine prenatal screening. At that time, the woman was breastfeeding her 2-year-old daughter and reported that she had been actively donating breast milk through social media groups since May of that year, having previously tested negative for HIV in 2023. Approximately two weeks after her diagnosis, her pretreatment HIV viral load reached 119,000 copies/mL, prompting medical teams to advise her to immediately stop breastfeeding. Her daughter began receiving postexposure prophylaxis on October 31 and subsequently tested negative for HIV twice.
According to the report, tracking down recipients proved difficult because investigators faced resistance from online administrators. As reported by Gizmodo, health officials struggled to gain entry into private social media groups, and once inside, group administrators refused to allow public safety announcements or warnings to be posted. To locate potential recipients, investigators cross-referenced the donor’s posts from May to October 2025 and reached out directly. TotalNews noted that officials used newly created profiles, direct messages, electronic medical records, and public health databases to contact families, though many parents initially met these outreach efforts with skepticism.
Testing and Exposure Risks of Unpasteurized Donor Milk
Out of the five cases identified by health authorities, investigators could not definitively confirm whether infants actually consumed the milk in four of the instances. However, in the fifth case, the family had never used the breast milk and kept it safely frozen. This allowed laboratory personnel to test the specific sample for HIV antibodies, revealing low levels of the virus at fewer than 30 copies/mL. Researchers emphasized that the presence of antibodies in stored milk does not automatically confirm an infectious virus or an active transmission risk.
Medical groups such as the American Academy of Pediatrics recommend breastfeeding for its established health benefits, but advise against it for mothers with an HIV viral load exceeding 50 copies/mL. Infants exposed to potentially contaminated milk face strict testing protocols immediately after their last exposure, followed by follow-up screenings at 14 to 21 days, 4 to 6 weeks, and 4 to 6 months.
Did you know? Accredited milk banks routinely pasteurize donor milk and thoroughly screen all donors for infectious diseases and medications that could potentially harm an infant, providing a regulated alternative to informal peer-to-peer sharing networks.
Public Health Guidance on Regulated Milk Banks
Health officials emphasize that utilizing accredited milk banks remains the safest route for families who cannot produce their own milk but wish to feed their infants human milk. Unregulated milk acquired through peer-to-peer networks carries inherent risks of bacterial or viral contamination due to improper storage and lack of screening. TotalNews pointed out that accredited institutions screen for infectious diseases before pasteurization, offering a secure supply for parents.
The investigation also underscores how public health agencies must adapt to digital platforms. Vaidya and co-authors wrote that social media presents a novel avenue for disease investigation, suggesting that health departments would benefit from specialized training on how to safely conduct inquiries through verified profiles within online communities.
Frequently Asked Questions
Can HIV be transmitted through breast milk?
Yes, HIV can be transmitted through breast milk if the mother’s viral load is sufficiently high, though modern antiretroviral treatments significantly lower this risk when infections are well-managed.
Are babies who received the social media donor milk infected?
No. According to public health data, all potentially exposed infants tested negative for HIV following the incident.
What is the safest way to obtain donor breast milk?
Health officials recommend obtaining donor milk exclusively through accredited milk banks, which screen donors for infectious diseases and pasteurize the product to eliminate pathogens.
What should parents do if they used informal donor milk?
Parents who suspect their child was exposed to improperly screened milk should consult a pediatrician immediately to discuss appropriate diagnostic testing timelines.
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