During the window period, the HIV virus is already present in the infected person’s body. Unprotected sexual contact with this individual can still lead to HIV transmission.

However, because the infection is recent, the markers the test looks for (such as antibodies) have not yet reached detectable levels. This can result in a false negative result. That is why doctors recommend testing after the window period to confirm infection status.

Transmission risk during this stage is relatively lower, mainly because viral load is typically still low in the early window period, making the infection less contagious.