Viral infections affect many organs of the body. The skin is one such organ affected by viruses, either as the primary target or as a signal of ongoing systemic infections. The principal skin manifestation of a viral infection is a rash. The characteristics of the rash usually identify the causative virus, though close similarities and overlap of symptoms may make this process very difficult.
These are typically seen in children. They present with fever and a characteristic rash. The impact of these viruses has been grossly reduced by the introduction of the immunization program.
Measles is a condition caused by the morbillivirus. It's highly contagious. The rash starts behind the ears and spreads downward to the trunk and extremities. The rash is typically itchy, patchy or blotchy (maculo-papular) and heals with dry skin peeling off the body. The systemic complications can be fatal, especially in undernourished people.
Chicken pox is caused by the Varicella Zoster virus. The rash comes in waves and appears as little itchy, fluid-filled pimples called pustules. The rash tends to stay close to the center of the body, on the trunk, sparing the limbs. It's also highly infectious but less fatal than measles.
Rubella, also called German measles, typically presents with a rash that looks like measles but is accompanied by swelling of the lymph glands at the back of the head and around the neck. It's devastating to the fetus when it infects pregnant women.
Roseola Infantum is caused by the human herpes virus, Type 6. It presents with a rash involving the neck and trunk that resembles the measles rash.
Fifth disease (or Erythema Infectiosum) has a characteristic rash that's also called the Slapped-Cheek rash, because it involves bright redness of both cheeks. It's caused by infection with Parvovirus B-19.
This condition is caused by the human papillomavirus. In children, it presents as common warts, plantar (sole of the foot) or palmar warts. In young adults, it usually presents as genital warts and is a sexually transmitted disease that's seen as itchy, fleshy growths on the skin around the anus and genitals.
The herpes simplex viruses typically produce reddened pustular rashes that are itchy, burning or painful. There are two viral types. The Type1 typically produces rashes on the face and upper body. The Type2 is usually sexually transmitted and produces rashes around the genitalia and anus.
The herpes simplex viruses can also cause an allergic skin condition called Erythema Multiforme. As the name implies, this rash takes on many forms.
This is caused by the same agent that causes chicken pox. Here, the rash follows the pathway of a particular nerve from its origin in the spinal cord. It's intensely itchy and burns. When the nerve concerned is the one supplying the skin over the eye, it could lead to blindness.
This is a contagious skin disease caused by a poxvirus. It usually appears as a single raised bump with an indented center. It can occur anywhere in the body. Because it's spread by direct skin contact, it's often seen around the groin or chest when transmitted by intimate contact.
HIV infection leads to a deficiency in the body's defenses. Any viral illness, such as those mentioned above, automatically runs a more severe course than in patients with a healthy immune system.
HIV also opens the way for other opportunistic infections to attack the body. The fungi (like Candida) and bacteria (like Streptococci) grow unhindered and give rise to severe skin infections.
Kaposi's Sarcoma, a rare kind of skin cancer linked to Human Herpes Virus-8, is seen in severe HIV infection.
Other Viruses That Cause Skin Problems
The Epstein-Barr virus, a type of herpes virus, causes infectious mononucleosis. This is a febrile illness with swelling of the lymph glands and a generalized skin rash.
Cocksakievirus A16 causes the Hand-Foot-and-Mouth-Disease. This is characterized by small painful ulcers in and around the mouth, on the hands and feet.