It is entirely possible for a couple who is faithful to one another to contract or transmit herpes simplex virus (HSV). HSV is a common, chronic infection that often produces no noticeable symptoms, meaning one partner may have been carrying the virus for years without knowing it. Herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) are highly prevalent worldwide, and the virus has a unique biological mechanism that allows it to be transmitted silently. The confusion about “faithfulness” arises because the infection may have been acquired long before the current relationship began, allowing transmission without any signs of an active outbreak.
Viral Latency and the Timeline of Infection
The ability of HSV to remain in the body for decades without causing symptoms is due to a process known as viral latency. After the initial infection, the virus travels along nerve pathways to the sensory nerve ganglia, which are clusters of nerve cells. For genital herpes, HSV-2 typically retreats to the sacral ganglia at the base of the spine. Once in the nerve ganglia, the virus enters a dormant state where it remains latent for the rest of the person’s life. This biological hiding allows the virus to evade the immune system and makes it impossible to eradicate with current antiviral medications. The latent virus can periodically reactivate and travel back down the nerve to the skin’s surface, often triggered by factors like physical or emotional stress, illness, or hormonal changes. While reactivation sometimes results in a noticeable outbreak of sores, it frequently occurs without any symptoms, which is the key mechanism for transmission in long-term relationships.
Asymptomatic Shedding and Transmission
The primary way HSV is passed between faithful partners is through asymptomatic shedding, a process distinct from latency. Asymptomatic shedding occurs when the virus reactivates and travels to the skin’s surface to replicate, releasing infectious virus particles onto the skin or mucosal surfaces without causing any visible sore or symptom. This silent shedding is a common occurrence, especially with HSV-2, which can be shed on approximately 10% of days annually, even in people who have never had a recognizable outbreak. Genital HSV-1 infections shed less frequently, and the rate of shedding for both types tends to be highest in the first year after infection. Because shedding episodes can be brief, often lasting only about a day, they are virtually impossible to predict or detect. The majority of new genital herpes transmissions occur during these periods of asymptomatic shedding, as people are unaware they are infectious and do not take precautions. While barrier methods like condoms can reduce transmission risk, they are not completely protective against silent shedding if the virus is shed from an area not covered by the condom. This biological reality explains how a couple can maintain complete sexual exclusivity yet still experience a transmission event.
Identifying the Virus Through Testing
For couples concerned about the virus, identifying who is infected, and with which type, requires specific diagnostic testing. If an active sore or lesion is present, a healthcare provider can take a swab for a viral culture or a Nucleic Acid Amplification Test (NAAT), such as a PCR test, which detects the virus’s genetic material. The PCR test is generally more sensitive and is the preferred method for confirming an active outbreak. Since most people with HSV have no symptoms, a blood test is required to determine past exposure. The most reliable test is the type-specific immunoglobulin G (IgG) antibody test, which looks for the antibodies the immune system produces to fight the virus. These IgG antibodies remain detectable for a lifetime and can distinguish between HSV-1 and HSV-2 exposure. The IgG antibody test has a window period; it can take anywhere from three to twelve weeks, or sometimes longer, for the body to produce enough antibodies for the test to register as positive. Testing too soon after a potential exposure may result in a false-negative result. A positive IgG test indicates that a person has been infected at some point in their life, even if they have never had an outbreak.
Disclosure and Risk Reduction
A new diagnosis within a long-term, faithful relationship requires open communication between partners to address the emotional context and reduce future transmission risk. Understanding that the infection was likely acquired years ago, perhaps from a previous partner, can help alleviate any misplaced concerns about recent infidelity. One of the most effective ways to reduce transmission is through the use of daily suppressive therapy, which involves taking a prescription antiviral medication, such as valacyclovir or acyclovir, every day. Studies show that this daily regimen significantly limits the frequency of asymptomatic viral shedding and can reduce the risk of transmission to the uninfected partner by approximately 50% for HSV-2. Beyond suppressive therapy, couples should avoid sexual contact during any period when symptoms are present, even if the symptoms are mild or atypical. Understanding the signs of recurrence and communicating them immediately is part of a risk reduction strategy. Antiviral medication can also be taken episodically at the first sign of an outbreak to shorten its duration and reduce the viral load.