What is chickenpox?

Varicella and herpes zoster by the varicella – zoster virus, chicken pox is the virus of acute invasive phase of the performance, while the incubation period of herpes zoster is the re-activation performance.

Highly contagious chicken pox. Is generally believed that chickenpox is through infected droplets from the nasopharynx, in a short prodromal period and the early rash are most infectious. The incubation period is usually 14 to 16. Since the pathogenic potential exposure began after 10 to 21 that is infectious to others. When, after the final scab lesions are no longer contagious. After the first batch of chicken pox occur isolated on the 6th in general be able to control cross-infection. Impossible (the immune system through a third party) Indirect transmission occurs.

Epidemic occurred in the winter and early spring, to 3 ~ 4-year cycle of epidemic (also emerged a number of new susceptible once again popular cause of the condition), since her birth until the susceptibility to the disease is high, but some babies 6 months before the partial immunity through the placenta.

Symptoms and signs

After exposure to pathogens 11 ~ 15, about the first before the appearance of skin lesions, about 24 ~ 36 hours, a mild headache, moderate fever and discomfort. Child care is generally not easy to find prodromal period of children over 10 years of age, there may be prodromal phase, while in adults the symptoms are prodromal phase usually very serious.

When the rash began to appear as a rash, often accompanied by short-term congestion. This rash within a few hours that become particularly itchy blisters on a single tear drop-shaped cavity containing clear fluid around in order to flush; diagnosis can be made at this time. Typical chickenpox in the 6 to 8 hours from the rash progressed to the papules, vesicles, and began to scab. Lesions appeared continuously in batches, in the former group after the rash began to scab appeared a number of rash. In severe cases, skin rash may be systemic in nature; otherwise, part of the face and limbs, skin rashes less, mainly seen in the upper torso, damage can also be found in the mucous membranes, including the pharynx, upper respiratory tract, palpebral conjunctiva, rectum, vagina mucosa. In the mouth, blisters immediately ulceration, often causing pain in swallowing, which vesicular stomatitis and herpes blisters is difficult to identify. Larynx or trachea blisters can cause severe breathing difficulties. Lesions can also be found leading to the occipital scalp, and neck lymph nodes under the tenderness. Varicella acute phase usually lasts 4 to 7 days, the general to the first 5 are no longer the appearance of new skin rash, to the first 6 most of scab. After the onset within 20 Most crusts off.

Complications

Chickenpox can cause erysipelas secondary to streptococcal infection, sepsis, acute hemorrhagic nephritis, may occasionally cause skin gangrene. Staphylococcus aureus infection also caused blisters and bullous impetigo. Pneumonia as a serious complication of chickenpox usually seen in adults and newborns and immune deficiency cases, but rare in young children. It is reported that there complicated by myocarditis, transient arthritis or hepatitis and hemorrhagic illness. Right to a hemorrhagic varicella with chickenpox should be suspected in thrombocytopenic purpura associated or secondary bacterial septicemia, malignant disease and immune deficiency.

After chickenpox encephalitis rare, the incidence of “1 / 1000. The same as measles encephalitis, chicken pox after chickenpox encephalitis more in recovery time or recovery occurs after 1 to 2 weeks, the most common neurological complications of acute infection of cerebellar ataxia, may also occur transverse myelitis, cranial nerve palsy, and multiple sclerosis-like clinical manifestations. Encephalitis can be fatal, but complete recovery after central nervous system complications, prognosis is usually good, far better prognosis measles encephalitis. Reye syndrome is a rare serious complications, in the rash occurred after 3 ~ 8.
Diagnosis and prognosis

Department for viral antigen in the damaged immune fluorescence, culture, or serological examination, will be able to diagnosis. Need to identify the disease with the following: impetigo, infected eczema, insect bites and thorns sting. Drug eruption, contact dermatitis, the blood disease porphyria (summer blisters), a rare diffuse Coxsackie virus and herpes simplex virus infection.

Children’s Chickenpox prognosis is usually good, but occasionally serious and fatal cases. Adults and in patients with T-cell immune deficiencies (such as lymphocytic malignant disease) or those receiving corticosteroid therapy or chemotherapy, prognosis is serious, even fatal.

Prevention

Through intramuscular injection of varicella zoster immune globulin (derived from the serum of patients with herpes zoster rehabilitation), or varicella – zoster immune globulin (derived from the specific antibody with high titer stock of plasma) to prevent or alleviate the symptoms. Recommended dose is 125u/10kg (125u of the injection of about 1. 25ml), the maximum dose should not exceed 625u. This preparation should be injected within 96 hours of contact with the patient. This is mainly used for contact with a history of suffering from leukemia, immune deficiency syndrome or other serious weakness in susceptible patients, as well as suspected to have pregnant women. Mothers before delivery, from 5 to less than occurred after giving birth on the 2nd chickenpox, their newborn is also for prevention. If given immediately after exposure to pathogens inventory of high-dose gamma globulin of human blood can reduce the symptoms of chicken pox, but the need is too big (0. 6 ~ 1. 2ml/kg), it is generally not recommended. After the onset of these agents have no therapeutic value. Had a small number of children in the 7 days after contact with chickenpox continue to use 1 week of acyclovir as a preventive measure, but its efficacy still need further study. American Academy of Pediatrics advocates for no clear history of varicella infection in children are the use of varicella vaccine after birth, 12 to 18 months, the use of a, for more than 18 months without access to immunization in children can be in 19 months to 13 years old any time, a single dose, over the age of 13 have not received immunization, there is no history of infection are required two injections, separated by 4 to 8 weeks.

Advisory Committee on Immunization recommends that adults are susceptible to be vaccinated. Adults before vaccination serological examination to determine their immune status is not entirely necessary, in most cases is not worth it to do. The following vaccination in patients with varicella vaccine is not easy: accompanied by moderate to severe disease, patients with low immune function, pregnant women, receiving high-dose systemic corticosteroid treatment, and patients taking salicylates. Occasionally, patients with immune deficiency can be transmitted by contact with the family to the chickenpox vaccine strains, so if the immune deficiency disease by contact with the family occurred after the skin rash vaccinators are advised to stop their re-engagement. Able-bodied people on the immunity, inoculation of varicella vaccine could have the chicken pox vaccine-related, but is usually very low (less than 10 papules and vesicles), even if there are systemic symptoms are short-lived.

Treatment

Patients with mild symptomatic treatment only. Wet packing is only used to control the extreme itching and prevent scratching, scratches can cause the spread of infection and the scar left after healing.

Cases can be used for serious systemic antihistamines. As the blisters can easily be aureus and streptococcal infection, patients should always wash with soap and water, clothing should be clean, wash hands, clipping the nails. Unless there is secondary bacterial infection, antibiotic therapy is generally not given. Pairs of secondary aureus and β-streptococcal infection systemic application of appropriate antibiotics.

Immunity has been found that the average normal person, in the rash appears within 24 hours of oral acyclovir can slightly shorten the course of chickenpox and mitigate its severity, but no complications of otherwise healthy children, chickenpox This kind of positive response disease, generally do not advocate the routine use of such substances. Only moderate and severe patients, including severe skin lesions, associated with chronic lung disease, oral salicylate therapy or intermittent aerosol with hormone therapy, oral acyclovir was advocated. A daily dose of 80mg/kg, sub-4 second oral, maximum daily dose of 3200mg. For patients with immune deficiency, acyclovir 1500mg/m2 body surface area per day, divided into three sub-interval of 8 hours intravenous injection, but some scientists proposed drug on the immune defect or a child under the age of 30mg/kg body weight per – calculations. Zoster immune globulin can also be used for this disease, so that to alleviate the course of the disease.