When are the highest number of Coxiella burnetii organisms shed in animals?

When are the highest number of Coxiella burnetii organisms shed in animals?

• A. During lactation
• B. During weaning
• C. During normal gestation
• D. In conjunction with adverse pregnancy events

Answer: (D)

The amount of Coxiella burnetii shed is highest when pregnancy is abnormal, such as during abortion or other adverse pregnancy events. This is because the placenta and fetal tissues harbor very high bacterial loads. During abortion, parturition, or other disruptions of normal pregnancy, birth fluids, placental membranes, and fetal products are released in large quantities, creating a burst of organisms that can become aerosols and contaminate the environment. That intense shedding greatly increases the risk of transmission to other animals and to humans who inhale contaminated air or dust. In contrast, normal gestation tends to have a lower bacterial burden, lactation may involve some shedding into milk but at much lower levels than birth products, and shedding during weaning isn’t tied to placental tissues, so it’s not a major source.

The amount of Coxiella burnetii shed is highest when pregnancy is abnormal, such as during abortion or other adverse pregnancy events. This is because the placenta and fetal tissues harbor very high bacterial loads. During abortion, parturition, or other disruptions of normal pregnancy, birth fluids, placental membranes, and fetal products are released in large quantities, creating a burst of organisms that can become aerosols and contaminate the environment. That intense shedding greatly increases the risk of transmission to other animals and to humans who inhale contaminated air or dust.

In contrast, normal gestation tends to have a lower bacterial burden, lactation may involve some shedding into milk but at much lower levels than birth products, and shedding during weaning isn’t tied to placental tissues, so it’s not a major source.