PI calves can be devastating to a herd. One in 12 herds have a BVDV-positive case, but they might not be aware of it.1
Quietly Spreading the Virus for a Lifetime
![An icon of cells representing cattle fetus being infected with BVDV.](/cattle/sites/default/files/2024-01/ExpressFP-TopReasons-Chart_Icon-02.png)
Calves become infected while in the uterus
![Cow heads in grey with eyes crossed out showing those infected with BVDV](/cattle/sites/default/files/2024-01/ExpressFP-TopReasons-Chart_Icon-03.png)
About 50% of PI calves will be “poor doers” and die before about 1 year of age
![Chart in dark grey showing the downward trend of a cows immune system with BVDV](/cattle/sites/default/files/2024-01/ExpressFP-TopReasons-Chart_Icon-04.png)
The virus suppresses the immune system, making calves more susceptible to other diseases
![Grey image of a cow and spy glass showing how it's hard to see if a calf has BVDV](/cattle/sites/default/files/2024-01/ExpressFP-TopReasons-Chart_Icon-05.png)
Other PI calves often show no signs of disease when they’re born
![One cow in grey and multiple cows in blue showing how BVDV can be spread](/cattle/sites/default/files/2024-01/ExpressFP-TopReasons-Chart_Icon-06.png)
They’ll continue to shed the virus daily, exposing other cattle
![Circle with 70-100% in it showing how many cows can be infected with BVDV from a PI calf](/cattle/sites/default/files/2024-01/ExpressFP-TopReasons-Chart_Icon-07.png)
70-100% of non-vaccinated or immunocompromised cattle become infected when exposed to a PI calf2,3