HERPES SIMPLEX VIRUS INFECTIONS PPT.pptx

Herpes Simplex Virus Infection

1. HERPES SIMPLEX VIRUS INFECTIONS INRODUCTION Herpes viruses are a group of DNA viruses that cause a variety of infections in humans and animals. There are several types of herpes viruses, each capable of causing distinct conditions. The two most common herpes viruses that infect humans are herpes simplex virus (HSV) and varicella-zoster virus (VZV). HSV is further divided into HSV-1 and HSV-2.

2. TYPES Herpes Simplex Virus (HSV): HSV-1: This strain commonly causes oral herpes, characterized by cold sores or fever blisters around the mouth and on the lips. However, it can also lead to genital herpes through oral-genital contact.

3. HSV-2 : This strain primarily causes genital herpes, resulting in painful sores in the genital area. However, HSV-2 can also cause oral herpes through oral-genital contact.

4. ORAL HERPES (HSV-1): Cause : Primarily caused by herpes simplex virus type 1 (HSV-1). Symptoms: Often results in cold sores or fever blisters around the mouth and lips. Symptoms may include tingling, itching, or burning sensations before the appearance of blisters. These blisters eventually break, forming painful sores that can crust over before healing.

5. Transmission of oral herpes : Typically transmitted through oral contact, such as kissing or sharing utensils, with an infected person. It can also spread to the genital area through oral-genital contact, resulting in genital herpes caused by HSV-1.

6. GENITAL HERPES (HSV-2 OR HSV-1): Cause: Primarily caused by herpes simplex virus type 2 (HSV-2. Genital herpes can also result from HSV-1 through oral-genital contact. Symptoms: Results in painful sores or blisters in the genital area, including the vulva, vagina, penis, or anus. Symptoms may also include itching, burning, or tingling sensations before the appearance of lesions. Like oral herpes, these blisters eventually break, forming ulcers that scab over and heal.

7. Transmission: Primarily transmitted through sexual contact, including vaginal, anal, or oral sex. It can also spread to the mouth through oral-genital contact, causing oral herpes caused by HSV-2.

8. CAUSATIVE AGENT Both HSV-1 and HSV-2 are DNA viruses with a similar structure and mode of transmission. These viruses can infect various parts of the body, establishing latent infections in nerve cells after the initial infection.

9. PATHOPHYSIOLOGY OF HSV INFECTION

10. 1. Entry and Initial Infection: Exposure: HSV is transmitted through direct contact with infected skin, mucous membranes, or bodily fluids. Entry Points : The virus enters the body through breaks in the skin or mucous membranes, where it gains access to epithelial cells.

11. 2. Replication and Spread: Attachment and Entry : HSV binds to receptors on the cell surface, allowing entry into host cells. Once inside, the virus releases its genetic material (DNA) into the host cell's nucleus. Replication : Viral DNA replicates within the host cell, producing viral proteins and new viral particles. Cell-to-Cell Spread : The virus can spread to adjacent cells, causing lytic infection and tissue damage. This process leads to the formation of characteristic lesions or blisters associated with HSV infection.

12. 3. Establishment of Latency: Nerve Cell Invasion : After the initial infection, HSV travels along sensory nerves and establishes latent infection within nerve cells, usually in sensory ganglia near the initial site of infection. Viral Dormancy : During latency, the viral DNA persists within the nuclei of neurons without causing active replication or symptoms. The virus evades the immune system during this dormant phase.

13. 4. Reactivation and Recurrent Outbreaks : Triggers for Reactivation: Various factors, including stress, illness, hormonal changes, UV exposure, or immune suppression, can trigger the reactivation of latent HSV. Viral Replication and Recurrence : Reactivation leads to the transport of the virus back along the nerve fibers to the initial site of infection, resulting in recurrent viral replication and the emergence of new lesions or outbreaks.

14. 5. Immune Response: Innate and Adaptive Immune Responses: The body's immune system plays a crucial role in controlling and limiting HSV infection. Innate immune responses initially combat the virus, followed by adaptive immune responses involving antibodies and immune cells that help control but do not eliminate the virus.

15. CLINICAL MANIFESTATIONS Primary Infection : Oral Herpes (HSV-1) : Painful blisters or cold sores around the mouth, lips, gums, or throat. Fever, swollen lymph nodes, and general malaise. Pain or soreness during eating or drinking. Sometimes, lesions can spread to the inside of the mouth or on the tongue.

16. Genital Herpes (HSV-2) : Painful blisters or sores in the genital area, including the vagina, penis, buttocks, and anus. Painful urination. Fever, headache, muscle aches, and swollen lymph nodes in the groin area. Lesions may cause discomfort or itching.

17. Recurrent Infections : Recurrent episodes are typically less severe than the primary infection. Individuals often experience prodromal symptoms (tingling, burning, or itching sensation) before the appearance of lesions. Lesions tend to be milder and heal faster than during the primary infection.

18. Systemic Symptoms : Some individuals may experience flu-like symptoms during primary or severe recurrent infections, including fever, headache, fatigue, and muscle aches.

19. Neonatal Herpes : Neonates born to mothers with active genital herpes can develop severe infections. Symptoms can include skin, eye, mouth, or central nervous system involvement. Neonatal herpes can be life-threatening and requires immediate medical attention.

20. Herpetic Whitlow : A herpes infection on the fingers, often seen in healthcare workers or individuals who come into contact with active lesions. Painful lesions on the fingers, causing redness, swelling, and sometimes blistering.

21. DIAGNOSTIC EVALUATIONS

22. MANAGEMENT OF HSV INFECTIONS

23. Supportive Measures : Keeping the affected area clean and dry can aid in preventing secondary bacterial infections. Applying cool compresses or ice packs to the lesions may provide relief from pain and inflammation. Adequate hydration and maintaining good hygiene are essential during an outbreak.

24. Prevention of Transmission : Avoid direct contact with active lesions to prevent transmission to other individuals. Practicing safe sex, including the use of condoms, can help reduce the risk of transmitting genital herpes.

25. COMPLICATIONS OF HSV INFECTIONS

26. Complications in Pregnancy: Pregnant women with genital herpes can transmit the virus to their babies during childbirth. This can lead to neonatal herpes, a serious condition that may result in brain damage, developmental issues, or even death in newborns. Caesarean section delivery may be recommended for women with active genital lesions close to delivery to prevent transmission.

27. Systemic Infections : In rare cases, especially in individuals with weakened immune systems, HSV can cause systemic infections that spread throughout the body. This can lead to conditions like disseminated herpes infection, affecting multiple organs and potentially becoming life-threatening if not treated promptly.

28. Meningitis and Encephalitis : HSV can cause inflammation of the brain (encephalitis) or the membranes surrounding the brain and spinal cord (meningitis). Herpes simplex encephalitis is a severe and potentially life-threatening condition that requires immediate medical attention.

29. Increased Risk of HIV Transmission : HSV infection, particularly genital herpes, can increase the risk of acquiring and transmitting the human immunodeficiency virus (HIV) due to the presence of open sores or lesions that serve as entry points for HIV.

30. Psychological Impact : Living with recurrent herpes outbreaks can lead to psychological distress, stress, anxiety, and social stigma due to the contagious nature of the infection.

31. PREVENTION OF HSV INFECTIONS