单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,VARICELLA(Chickenpox),Divide of gastroenterology and infectious diseases,Children,s hospital,Wang Yuting,Overview,Varicella(chickenpox)is the primary infection caused by varicella-zoster virus(VZV).,Varicella is characterized by the appearance on the skin and mucous membranes of successive crops of typical vesicles,generally accompanied by a mild constitutional reaction.,Varicella-zoster virus(VZV),Family:Herpesviridae,Subfamily:Alpha herpesvirinae,Serotype:Only one,latent infection-reactivation,Etiology,Locations:,Patients respiratory secretions,blood,vesicle fluid,Resistance:,Sensitive to heat,acid and disinfectant,Etiology,Infectious sources,:,Patients,The infective stage is from about 24 hr before the appearance of the rash to all lesions are crusted,Epidemiology,Routes of transmission,:,Respiratory transmission,:spread by droplet,、,Direct contact,、M,other-to-fetus,Epidemiology,Population susceptibility,：,90%of reported patients are under 10-yr of age.,The peak age of incidence is 2-6 yr.,Peak seasons:,winter and spring,Epidemiology,respiratory secretions or skin lesion,respiratory mucosa,regional lymph nodes,viremia,mononuclear cells,viremia,respiratory mucosa,skin,organs,Pathogenesis,V-z-v,characteristicchangeof pathology,：,Multinucleated giant cells,and intranuclear,inclusions,Pathology,Pathology,1.Maculopapule,2.Vesicles,3.Cloudy vesicles,(pustules),4.Crust,Angiotelectasis in dermis,Ballooning degeneration in celllayer,Apocytes invade in,vesicle,fluid,vesicle,fluid absorbed,Clinical Manifestations,1.Typical varicella,1)Incubation period:,the incubation period varies from 10-21 days,but the average is 13-17 days.,2)Prodromal period:,short,mild,there may be slight fever,malaise,or anorexia.,Rash Features:,1.rash development process:,maculopapule-“tear-drop”vesicles-cloudy vesicles(pustules)-crusts,2.rash characteristics:,appear in batches,(development of several crops of rash),four kinds of rash at the same time,concentric distribution,mucosa involvement,3.rash sequence:,trunk-face and scalp-extremities,rash pruritus,Clinical Manifestations,Clinical Manifestations,1.Severe varicella:,2.neonatal varicella,3.,congenital varicella,1)Secondery bacterial infection,the skin lesions is the,most common,complication.,Such as impetigo,erysipelas,cellulitis,、,surgical scarflet fever,Complications,2)Central nervous system complications,Varicella encephalitis,the most common central nervous system complication.,Overall mortality rates vary from 5-25%.,About 15%of survivors have permanent sequelae of seizures,mental retardation,or behavior disturbances.,Complications,Other nervous system complications,Guillain-Barre syndrome,Reye syndrome,Transverse myelitis,Facial palsy,Optic neuritis,ect.,Complications,Complications,3)Varicella pneumonia,4)Others:,Myocarditis,Leukocytopenia,Nephritis,ect.,Blood routine:,a mild leukocytopenia,Multinucleated giant cells:,it can be demonstrated in scrapings from the floors of fresh vesicles.,serological study,Virus isolation:,virus can be isolated in human tissue culture cell lines.,Laboratory Data,Epidemiologic data,Age,Seasons,History of contact with patient,History of inoculation,Clinical data:,Typical rash,The diagnosis is usually made from the characteristic clinical picture,and laboratory confirmation is rarely needed.,Diagnosis,Differential diagnosis,1.Hand-foot-and-mouth disease,2.Urticaria papulosa,Treatment,1.Symptomatic treatment,Wear mittens and keeping nails short,Daily changes of clothes,2.Antiviral therapy:,Acyclovir,Interferon-,3.Complication treatment:,antibiotic therapy if there is a superinfection with bacteria,Cortical hormone is forbidded,Salicylic acid agent is not be used as possible,Prevention,1)Control of sources of infections,The patient will be isolated until all lesions are crusted,The susceptible contacts will be isolated for clinical observation for 3 weeks after exposure.,Prevention,2)Abrupt the ways of transmission,3)Protect the susceptible,passive immunization,zoster immune globulin(ZIG).,given within 72 hr of exposure.125-625U/10kg,active immunization,Varicella Attenuated Live Vaccine,Efficacy:85%-95%,more than ten years,The prognosis is usually good,Fatalities occur from the complications,Prognosis,Summary,Clinical Manifestations of typical varicella,Complications of varicella,Diagnosis and differential diagnosis of varicella,key points,Thanks,