How do foals commonly acquire equine herpesvirus?

Foals commonly acquire equine herpesvirus primarily through contact with their mother. During or shortly after birth, a mother horse can transmit the virus to her foal. This transmission often occurs if the mare is shedding the virus in her bodily fluids, such as in maternal secretions or through direct contact during nursing. This mode of transmission is particularly concerning since a foal's immune system is still developing, making them more susceptible to infections, including equine herpesvirus.

While contaminated feed, peer interactions, and environmental exposure can also play roles in the spread of viruses, the direct maternal transmission is the most significant pathway for foals concerning equine herpesvirus, especially considering the timing of exposure relative to birth and initial bonding. This emphasizes the need for careful management of pregnant mares to minimize the risk of passing the virus to their offspring.