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הרפס גניטלי
הרפס גניטלי הוא זיהום המועבר במגע מיני הנגרם בעיקר על ידי נגיף הרפס סימפלקס מסוג 2, או HSV-2, אם כי נגיף הרפס סימפלקס מסוג 1, או HSV-1, מעורב יותר ויו…
Genital herpes is a sexually transmitted infection caused primarily by the herpes simplex virus type 2.
HSV-2 commonly spreads through direct sexual contact. Transmission can occur even without visible symptoms due to asymptomatic viral shedding.
After initial exposure, symptoms usually appear within 4 to 7 days as painful vesicular lesions on the male and female genitals and the anal area.
These vesicular lesions contain clear fluid that is rich in infectious viral particles. When the vesicles rupture, they form ulcers, and contact with the fluid increases the risk of transmission.
After the first infection, HSV-2 travels to the sensory neurons located in the sacral dorsal root ganglia, where it can remain dormant for months or years.
Reactivation of the virus is triggered by physical or emotional stress, fatigue, or immune suppression, leading to milder recurrent outbreaks.
In rare cases, HSV-2 can be transmitted from mother to child during childbirth, especially if the mother contracts HSV-2 for the first time in late pregnancy.
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Q1: How does herpes simplex virus type 2 spread between people?
HSV-2 primarily spreads through direct sexual contact with infected individuals. Transmission can occur even without visible symptoms due to asymptomatic viral shedding, making it difficult to control at a population level. The virus is present in clear fluid within vesicular lesions, and contact with this fluid significantly increases transmission risk.
Q2: What are the initial symptoms of genital herpes infection?
Primary HSV-2 infection typically causes painful vesicular lesions on the genitals and anal area, appearing within 4 to 7 days after exposure. More severe primary infections may include systemic symptoms such as fever, malaise, dysuria, and lymphadenopathy. When vesicles rupture, they form ulcers containing infectious viral particles.
Q3: Where does HSV-2 hide in the body after initial infection?
After primary infection, HSV-2 travels to sensory neurons in the sacral dorsal root ganglia, where it establishes latency. The virus persists in a transcriptionally silent state but can reactivate in response to physical or emotional stress, fatigue, immune suppression, or hormonal fluctuations, leading to recurrent outbreaks.
Q4: Why are recurrent herpes outbreaks typically milder than the first infection?
Primary HSV-2 infections are usually more severe than recurrent episodes because the immune system, particularly cell-mediated responses, develops control over viral replication during the initial infection. Host immunity limits the frequency of relapses and reduces outbreak severity. Recurrence patterns vary among individuals based on immune competence and triggering factors.
Q5: How is genital herpes diagnosed in clinical practice?
Genital herpes diagnosis is confirmed using polymerase chain reaction (PCR), viral culture, or serological testing for HSV-specific antibodies. PCR is the most sensitive method and is preferred in clinical practice for accurate identification of HSV-2 infection and distinguishing it from other viral infections.
Q6: What complications can genital herpes cause for immunocompromised patients?
In immunocompromised individuals, HSV-2 infections can be more severe and disseminated. Genital herpes also increases susceptibility to other sexually transmitted infections, particularly HIV, because mucosal disruption and inflammatory environment facilitate viral entry. Antiviral therapies reduce outbreak severity but do not eradicate latent virus.
Q7: Can suppressive antiviral therapy reduce transmission of genital herpes?
Suppressive therapy with daily antivirals such as acyclovir, valacyclovir, and famciclovir decreases recurrence frequency and lowers the risk of transmission to sexual partners. While these therapies reduce the severity and duration of outbreaks, they do not eradicate the latent virus, making ongoing suppressive therapy an important public health strategy.