Viral diseases of honeybees

Question 1

Cause

Answer 1

-Many viral infections have been strongly correlated with the presence of nosema and varroa mites
- While they feed and infect bees, the parasites create an opportunity for viral particles to enter the body of the bee or larvae
- These conditions can cause viruses to be lethal
- Environmental and nutritional stresses can also make bees more susceptible to viral infections
Other hive diseases

Question 2

Distribution

Answer 2

Most commonly found in Europe, Japan, West Asia and North America

More than 20 bee viruses are worldwide

Question 3

Transmission

Answer 3

• Varroa and Nosema mites carry viruses externally and internally
• Bee viruses rely on other organisms as a vector to enter a honey bee host
• Damage caused by Varroa mites enabled viruses to be directly introduced into the body cavity of bees
• Food-borne transmission
• Body fluid transmission
  Vector transmission

Question 4

Life Cycle

Answer 4

• Varroa mites (vectors for bee viruses) do not live long away from a host
• 1-2 female varroa mites enter a brood cell before it is closed and lay 5-6 eggs each
• Newly hatched nymph mites feed on bee larvae
• Mature mites mate and the male dies
• Females attach themselves to adult bees and feed off their blood
• Viruses are transmitted as they feed

Question 5

Impact on host

Answer 5

• May be trembling and display uncoordinated movement
• Hosts eventually die
• Weak bees that do not live long
• Stunted wings, missing legs + other deformities

Question 6

Treatment

Answer 6

• Use of chemicals to kill mites
• Bee viruses cannot be treated