As an STD assistant, I understand your concern about transmitting herpes simplex virus type 2 (HSV-2) to a partner who has herpes simplex virus type 1 (HSV-1). The probability of transmitting HSV-2 to someone with HSV-1 can vary depending on several factors.

First, it's important to note that having HSV-1 does not provide complete protection against acquiring HSV-2. However, people with HSV-1 may have partial immunity, which can reduce the risk of contracting HSV-2.

The risk of transmitting HSV-2 to a partner with HSV-1 is highest during an active outbreak or when there are visible sores or lesions present. The virus can be shed and transmitted even when there are no symptoms, but the risk is lower during these asymptomatic periods.

Factors that can increase the risk of transmission include:

1. Frequency of outbreaks
2. Severity of outbreaks
3. Lack of suppressive antiviral therapy
4. Engaging in unprotected sexual activity during outbreaks

While it's difficult to provide an exact probability, studies suggest that the risk of transmitting HSV-2 to a partner with HSV-1 is lower compared to transmitting it to someone without any herpes infection.

It's crucial to practice safe sex, disclose your status to your partner, and consider suppressive antiviral therapy to reduce the risk of transmission. Additionally, consulting with a healthcare professional can provide you with more personalized guidance based on your specific situation.

Remember, open communication, regular testing, and taking appropriate precautions can help manage the risk of transmitting HSV-2 or any other sexually transmitted infection (STI). If you have any further concerns or need additional support, I encourage you to reach out to healthcare professionals or seek guidance from reputable sources.