Saccular brood of bees: causative agent and characteristic signs, how to treat

Saccular brood of bees: causative agent and characteristic signs, how to treat

Infection of bees with infectious diseases is a common phenomenon that causes significant economic damage to beekeepers. In order to successfully deal with the sac brood of bees, it is important to correctly diagnose the disease and start treatment in a timely manner. In order to prevent the death of a significant number of bee colonies, regular disease prevention is carried out.

What is bag brood?

Infectious disease of printed brood of bees, caused by a virus, is called sac brood. It is noteworthy that adult bees do not get sick with the virus, but can be its carrier.The disease affects larvae (drones, queens and worker bees) 2-3 days old. Since the duration of the incubation period is 5-6 days, adult larvae die in the pupation phase.

Cells with diseased larvae turn dark. Wax combs show a variegated appearance as dead larvae can be found anywhere.

Causes and signs of disease

The virus appears and spreads in late May or early June. The causes of the onset of the disease can be different:

  • damp cool weather;
  • placement of beehives in shady damp areas;
  • wandering virus carrier bees;
  • poor insulation of hives, lack of nutrition significantly weaken bee colonies.

Characteristic signs of the disease: variegated color of combs, corpses of larvae lying on the dorsal side, located along the cells, flabby appearance of the affected larvae.Features of the sac brood are the absence of a putrid odor and a peculiar viscous mass, which is usually present when the corpses of larvae are removed.

The causative agent of the disease is a neurotropic virus, which is localized in the cytoplasm of bee brain cells.

Diagnostic methods

The diagnosis cannot be unambiguously determined based on the external symptoms of the disease, since signs of infection may be similar to European and American foulbrood. To eliminate diagnostic errors, a sample of cells is examined with parameters of 10x15 cm. Modern laboratory methods: polymerase chain reaction, chemiluminescence, enzyme immunoassay. As a rule, the final results of the analyzes are known after 10 days.


Most often, the infection begins to appear in late spring or early summer. It is expedient to treat families weakly and moderately affected. If the degree of damage is significant, then the family is destroyed. An abundant summer honey plant can dampen or even stop the spread of the disease. However, the activity of the virus rises in late summer or next spring. It is recommended to use medicines to treat the disease.


The drug to combat brood disease comes in the form of cardboard strips soaked in the antibiotic rifampicin.

To treat bees, the strips are hung for 2-3 weeks between the frames in the middle of the streets (in places where insects are most concentrated, at the rate of 2 strips for 10-12 frames).Advantages of the drug: a wide range of bactericidal action, no toxicity to bees, does not affect the development and productivity of bee colonies.

Precautions when using "Bactopol": at the end of work with the drug, you need to wash your hands with soap and water, honey can be pumped out and eaten 3 weeks after treatment.


An antimicrobial drug is added to the syrup at the rate of 1 g per liter of syrup.

Feeding is done in the evenings (3-4 times, with a five-day interval).

Hyperimmune Serum

For preventive and therapeutic purposes, hyperimmune serum obtained from rabbits or horses is used. The drug is available as a clear liquid of dark or light straw color.To prepare a remedy, add 80 ml of whey to a liter of sugar syrup.

Method of treatment: 150-200 ml is given three times to the street of bees, with an interval of 5 days. The advantage of whey - contributes to the formation of sustainable immunity to diseases.


Only ensuring decent conditions for keeping bees will prevent the emergence and spread of a viral infection:

  • food should be sufficient for all families;
  • in insect nutrition, be sure to include vitamin and protein supplements;
  • only strong bee colonies are kept in the apiary;
  • Hives are regularly inspected, especially during the wet and cool spring weather;
  • dry, well-lit areas are selected for placement of hives.

In the spring, after wintering, inventory is cleaned and disinfected (metal objects are heated with a blowtorch, honeycombs are treated with hydrogen peroxide (3% solution)).

Basic brood of bees, depending on the geographical location of the farm, may appear in late spring or early summer. During the summer honey plant, the manifestations of the disease disappear, but the infection does not completely disappear. Therefore, it is important to pay attention not only to therapeutic measures, but also to preventive ones.

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