Which statement best describes transmission of bovine spongiform encephalopathy to humans?

Which statement best describes transmission of bovine spongiform encephalopathy to humans?

• A. Prions are viruses that spread through blood transfusions
• B. Transmission occurs via inhalation of cattle aerosols
• C. Mad cow disease is transmitted to humans through ingestion of infected cattle meat and is caused by a prion protein
• D. It is not transmissible to humans

Answer: (C)

Prion diseases arise from misfolded proteins, not viruses. In bovine spongiform encephalopathy, infectious prions are present in the cattle’s nervous tissue. When people consume contaminated beef products, these prions induce misfolding of normal human prion proteins in the brain, leading to progressive neurodegeneration and variant Creutzfeldt-Jakob disease. The transmission route is ingestion of infected cattle meat, not inhalation of aerosols or blood-borne spread. That combination—transmission through eating contaminated beef and the involvement of a prion protein—is why this statement is the correct description.

Prion diseases arise from misfolded proteins, not viruses. In bovine spongiform encephalopathy, infectious prions are present in the cattle’s nervous tissue. When people consume contaminated beef products, these prions induce misfolding of normal human prion proteins in the brain, leading to progressive neurodegeneration and variant Creutzfeldt-Jakob disease. The transmission route is ingestion of infected cattle meat, not inhalation of aerosols or blood-borne spread. That combination—transmission through eating contaminated beef and the involvement of a prion protein—is why this statement is the correct description.