Highly pathogenic avian influenza virus (HPAIV) H5N1 has been detected in dairy cattle in the United States, with high viral loads observed in milk from infected animals. This raises public health concerns regarding potential transmission through exposure to raw milk. The sale of raw milk via vending machines represents a well-established distribution model in many European countries, including Switzerland. Although a notice must be posted on these milk vending machines stating that it is raw milk, together with appropriate processing instructions (heating to over 70 °C required, storage below 5 °C, consumption within 3 days), these notices are sometimes missing, and consumers often do not follow these guidelines. Over a four-month period, spanning from June 2025 to September 2025, 124 raw milk samples were collected from vending machines across Switzerland. Samples were screened for influenza A using reverse-transcription quantitative PCR (RT-qPCR). No samples tested positive for influenza A virus. The data from this study demonstrate the feasibility of implementing a sampling and detection system for HPAIV H5N1 in direct-to consumer raw milk samples and highlight the currently very low risk of HPAIV in raw milk samples sold via vending machines in Switzerland.

The sale of raw milk via vending machines represents a well-established distribution model in many European countries, including Switzerland. As part of this study, data on the microbiological quality of raw milk sold via vending machines in Switzerland were collected. A total of 124 raw milk samples from 124 raw milk vending machines across Switzerland were analysed. In addition to standard hygiene parameters (TVC and E. coli), the scope of the investigation particularly included foodborne pathogens as well as methicillin-resistant Staphylococcus aureus (MRSA) and extended-spectrum β-lactamase (ESBL)-producing Enterobacterales. Isolates were further characterised by whole-genome sequencing. Shiga toxin-producing Escherichia coli (STEC) were detected in 3.2%, Staphylococcus aureus was detected in 12.1%, Listeria monocytogenes was detected in 2.4%, Campylobacter spp. were detected in 1.6%, Yersinia enterocolitica was detected in 29.8%, and Salmonella spp. were detected in 0% of the samples. MRSA and ESBL-producing Enterobacterales were each detected in 0.8% of samples. The results highlight the potential risk of foodborne infections associated with the consumption of untreated raw milk, as well as hygiene deficiencies linked to several raw milk vending machines. Based on the generated data, the importance of the requested heat treatment of raw milk in Switzerland is clearly underscored. Furthermore, more precise and binding guidelines for self-monitoring and the management of raw milk vending machines appear necessary.