Which of the following sets lists all six pathogens most often discussed as targets in milk safety and pasteurization?

• A. Listeria monocytogenes, Salmonella spp., Campylobacter jejuni, Escherichia coli O157:H7, Brucella spp., and Coxiella burnetii
• B. Listeria monocytogenes, Salmonella spp., Staphylococcus aureus, Escherichia coli O157:H7
• C. Listeria monocytogenes, Salmonella spp., Campylobacter jejuni, Escherichia coli O157:H7
• D. Listeria monocytogenes, Salmonella spp., Brucella spp., Coxiella burnetii

Answer: (A)

Understanding which pathogens are emphasized in milk safety and pasteurization helps you see which risks pasteurization is designed to address. The six pathogens listed here—Listeria monocytogenes, Salmonella spp., Campylobacter jejuni, Escherichia coli O157:H7, Brucella spp., and Coxiella burnetii—are repeatedly highlighted because they are real public health threats linked to dairy and can be transmitted through milk or dairy products.

Listeria monocytogenes is a particular concern in dairy because it can grow even at refrigeration temperatures, so it poses a risk in stored milk and products. Salmonella and Campylobacter are common causes of bacterial gastroenteritis and are historically associated with dairy, especially unpasteurized milk. Escherichia coli O157:H7 is a shiga-toxin–producing strain that can cause severe illness, and dairy products can be a vehicle for exposure. Brucella spp. and Coxiella burnetii are classic zoonotic pathogens that can be transmitted from infected animals to humans via dairy, making them key targets in dairy safety and pasteurization standards.

The other options omit one or more of these high-priority pathogens, making them incomplete as lists of the six most often discussed targets in milk safety and pasteurization.