Streptococcus equi is best known for causing Strangles in horses. Which statement is most accurate?

Streptococcus equi is best known for causing Strangles in horses. Which statement is most accurate?

• A. It is a fungal infection
• B. It only affects foals under 1 year
• C. It is not contagious
• D. It is transmitted via direct contact and causes head and neck lymphadenopathy (Strangles)

Answer: (D)

Strangles is a contagious bacterial infection in horses caused by Streptococcus equi, and the hallmark sign is swelling of the head and neck lymph nodes (submandibular and retropharyngeal) that can form abscesses. Because the bacteria are shed in nasal discharges and on contaminated equipment and surfaces, transmission occurs readily through direct contact between horses and via shared tack, water buckets, feeders, and other fomites. This combination of contagious spread and the characteristic head/neck lymphadenopathy makes the statement correct, as it accurately captures both how the disease is spread and the key clinical feature. The other options are not accurate: it is not a fungal infection, it can affect horses of various ages (not just foals under 1 year), and it is indeed contagious.

Strangles is a contagious bacterial infection in horses caused by Streptococcus equi, and the hallmark sign is swelling of the head and neck lymph nodes (submandibular and retropharyngeal) that can form abscesses. Because the bacteria are shed in nasal discharges and on contaminated equipment and surfaces, transmission occurs readily through direct contact between horses and via shared tack, water buckets, feeders, and other fomites. This combination of contagious spread and the characteristic head/neck lymphadenopathy makes the statement correct, as it accurately captures both how the disease is spread and the key clinical feature. The other options are not accurate: it is not a fungal infection, it can affect horses of various ages (not just foals under 1 year), and it is indeed contagious.