Which of the following is one of the six diseases/pests considered by the OIE for honeybees?

• A. Nosema disease
• B. Africanized bees
• C. Small hive beetle
• D. Varroa mite

Answer: (D)

OIE focuses on the threats to honey bee health that are internationally notable for trade and surveillance. Varroa destructor is a major external parasite of honey bees that weakens colonies and, importantly, serves as a vector for several deadly viruses. That combination—direct parasitism plus virus transmission—makes it a primary item on the OIE list of diseases and pests to monitor and report, which is why it is the best answer among the options.

The other choices don’t fit as the listed disease/pest in this context. Africanized bees are a bee race rather than a disease or pest; Nosema disease is a bee disease, but in this specific list the standout item commonly recognized by the OIE is the Varroa mite; small hive beetle is a significant pest as well, but the question points to the well-known OIE-listed example, which is Varroa mite.