Datum objave: 5/10/2011 Chicken-pox – varicella DEFINITION AND EPIDEMIOLOGY Chicken-pox is an acute infectious disease which infects the young population primarily, seldom the adults. It is a benign disease which doesn’t cause major health problems to a normally healthy child. It is most common in 5-9 year-old children, which makes up for 50% of this disease occurrence. Chicken-pox epidemics are most often during the winter and spring period, the disease comes as a result of the first virus infection and is short lasting. The cause of chicken-pox is the varicella-zoster virus from the herpes virus group.The varicella-zoster virus is specific because, once in the host body, it never leaves, and its possible reactivation gives the clinical picture and symptoms of a new disease called herpes-zoster. In the initial phase of the disease, the disease agent is located on the mucous membrane of the respiratory system, and later transfers to the bloodstream, and can be isolated only later from the skin changes. The disease is transferred via droplets or direct contact and the virus penetrates the organism through respiratory mucous membranes and eye conjuctival sac. The infected person can transfer the disease over the period of two days before rash outbreak, six days after blistering, and even after blisters turn into scabs. CLINICAL PICTURE The clinical picture divides the disease into several stages: • Incubation stage usually lasts between 10 and 20 days, when the symptoms are yet to appear. It is the time when the virus penetrates the organism through mucous membranes and conjuctival membranes, spreads through the bloodstream over various body systems. In the final form, the most affected areas are the skin and respiratory system mucous membranes, however, other organs may be equally affected (liver, lungs, brain etc.). Toward the end of this stage, the virus re-inhabits the respiratory system, which makes the person infectious for the surrounding even before rash appears. • Primordial stage lasts one to two days and is followed by non-specific disease symptoms: mildly raised temperature, headache, nausea, weakness etc. • Eruptive stagelasts 5 to 7 days and is recognizable for its characteristic blistering rash and itching. First changes to the skin come in the form of small red dots (maculae) which appear on the scalp, face and torso. Over the following hours, they change into small, redness surrounded surface blisters. They are 2-3 mm in diameter on average and filled with clear virus-containing liquid. Simultaneous with the rash break-out on the skin and mucous membranes is the itch of infected areas. Over the following day or two, the content of the blisters blurs, they break, dry and turn into scabs which disappear without leaving scars. The development from maculae to scabs lasts two to three days, and with the appearance of first scabs, new maculae appear, vesicles, and the rash relocates from the head onto the extremities. The rash density is different and varies from a couple to entire body coverage. The varicella caused rash is sporadic, so all the phases are observable on the skin: maculae to scabs, which is an undisputable evidence of chicken-pox. Every new outbreak of rash may be followed by body temperature increase. • Regression stage is marked with the disappearance of the general symptoms of the disease, scabs disappearance and skin damage healing, which usually doesn’t leave scars. DIAGNOSIS No laboratory examinations are necessary for diagnosis; rather, it is based on sound anamnesis and clinical picture. The outward appearance of the rash is of special importance in the clinical picture, since the simultaneous presence of different stages of skin changes (maculae to scabs) and sporadic rash appearance are characteristic of chicken-pox. The diagnosis may be confirmed by a blood test which proves leucopenia, reduced white blood cells count, which proves normal in the differential blood tests. COMPLICATIONS The complications with the disease can be various and are mostly caused by inconvenient location of the rash, intense infection of other organ systems or added bacterial infections. By inconvenient location of the rash we mean its outbreak in the area of the pharynx, throat or eye which may cause serious consequences for the patient (respiratory problems, eyesight impairment etc.). One of the most common complications is the added bacterial infection, mostly infection of rash damaged skin or mucous membranes. If a woman in early pregnancy gets infected with the varicella virus, there is a risk of certain birth defects (rarely). In late pregnancy, the greatest risk for the child is one month before birth and immediately after. Newborns are under risk of serious infections if the mother is not immune to chicken-pox. The children present one of the highest risk groups and should be given varicella-zoster immunoglobulin (VZIG) in three cases: 1. If the mother has been exposed to varicella over the last month 2. If the mother showed a clinical picture of chicken-pox 5 days before due-date 3. If the mother showed a clinical picture of chicken-pox 10 after child birth TREATMENT Non-complicated forms of the disease are mostly cured symptomatically (rest, body temperature control, frequent warm water showering for skin infection prevention), ), while the treatment of complicated forms depends on the type of complication. The general itching relief methods include warm water baths with added solution of potassium permanganate until the water is mildly pink, careful rinsing and gentle wiping using towel taps. Over-the-counter products can also help: antihistamines, or other menthol, camphor or phenol containing lotions. They should be applied in small quantities onto the affected areas. Baby powder use is not recommended because the small particles in it build up on the skin and may prolong the infection. Nails should be clipped to reduce scratches from scratching which could additionally infect. You can put light cotton or flannel gloves on children hands to prevent scratching. It is recommended to avoid using salicylates (Aspirin, Andol) for body temperature control on chicken-pox patients due to the risk of Ray Syndrome onset with children under the age of 12! For body temperature control, use paracetamol. The medicine Aciklovir was approved by the FDA for chicken-pox treatment for children older than 2, however, it is mostly used on teenagers since the infection is more intense in this age group. The medicine should alleviate chickenpox symptoms, especially in older children and teenagers if taken 24 hours after rash outbreak. It can also be used in severe cases and with patients on immunosuppressive therapies. The patient isolation is recommended until the last blisters disappear, which usually takes five to six days after rash outbreak. Children shouldn’t attend schools or visit kindergartens until the blisters break and turn into scabs or until they feel well enough to participate in regular activities. PREVENTION Chicken-pox vaccination isn’t on the list of mandatory vaccination for children in our country, unlike the USA and some European countries. The decision is left to the parents in our country, and children can be vaccinated after 12 months of life. At that age, only one dose of vaccine was administered, and another two, at the age of 13, 6 to 10 weeks apart. According to latest recommendations, as of 2006, two doses of vaccine are given to children younger than 13. First dose is given between 12 and 15 months of life, and another at the age of 4 to 6 which results in 98% of immunity. Galen laboratory products for chicken-pox symptoms relief Related articles Allergies Nazad