Occasionally of one or more large joints, often the knee, follows mumps

delivery or within 24h after delivery. (d) Premature infants of less than 28 weeks gestation. (e) Premature infants whose mothers do not have a history of chickenpox. Dose - 125 units (1 25ml)/10kg body wt, i m within 48h and preferably not later than 96h after exposure Maximum suggested dose is 625 units. (2) Vaccine - Live attenuated varicella vaccine. Safe and highly protective in both healthy and immunocompromised children. Adverse effects - Minor rash, often accompanied by fever Dose In children 2-12 years, who have not had chickenpox, single dose of 0. 5 ml s. c , for older individual two 0. 5 ml doses 4-8 weeks apart. 8. SCARLET FEVER Etiology - Causative agent - Streptococcus pyogenes (Group A) producing erythrogenic toxin. Incubation period - 1-5 days Transmission - Droplet infection Clinical features - Stage of invasion - Sudden onset with sore throat, fever, headache and malaise. Lasts for 1-3 days. In mild case no symptoms of invasion except sore throat. 2. Meningitis - Usually follows parotitis but may occur at the same time or even before salivary gland enlargement. 3. Oophoritis - Less common than orchitis. Bilateral suprapubic pain. 4. Acute pancreatitis - in 2nd week Occasionally the disease presents with only orchitis, benign meningitis or pancreatitis without salivary gland involvement. Diabetes may be a sequel. B. RARE - 1. Neurological complications - (a) Meningoencephalitis - as a rule appears 3-10 days after onset of glandular swelling, but sometimes precedes it and at times appears in absence of glandular swelling. CSF cell count often 50-200 x 106 lymphocytes /litre with slightly raised protein. (b) Cranial nerve involvement - Facial, and auditory, nerve deafness may be permanent. (c) Polyneuritis usually temporary. 2. Arthritis - Occasionally of one or more large joints, often the knee, follows mumps, but no permanent damage results. 3. Mastitis - Mild and transient enlargement of breasts of either sex. Prostatitis - in males. 4. Thyroiditis. 5. Nephritis. 6. Foetal endocardial fibroelastosis - very occasionally during pregnancy, or if contacted in the first trimester, abortion Diagnosis - (a) Viral isolation -from saliva or nasopharynx in acute illness or from CSF in mumps meningitis. (b) Antibody tit re - Four-fold rise 1-2 weeks after infection. Differential Diagnosis - 1 INFECTION AND INFLAMMATION - (a) Acute suppurative parotitis - Painful, swollen, tender gland with oedema of subcutaneous tissues. Fever. Oedema and redness around orifice of parotid duct. Pressure over gland may produce flow of pus in mouth. (b) Recurrent parotitis - usually unilateral. Constitutional disturbance slight Gland may not be enlarged in quiescent stage but its limits are often palpable. X-ray after injection of lipiodol into ducts shows dilatation of ducts. (c) Chronic parotitis - Late stage of recurrent parotitis due to recurrent exacerbations,or associated - with calculus. 2. OBSTRUCTION - of major salivary ducts usually by salivary calculi, rarely by injury or tumor. 3. DRUG REACTIONS - Hypersensitivity to phenothiazines, thiouracil, iodides, thiocynates, isoprenaline, copper, lead and mercury 4 NEOPLASMS - So-called mixed tumor. A slow growing nodular or rounded, painless and mobile swelling, usually unilateral. 5. ASSOCIATED WITH SYSTEMIC DISEASE - (a) Sialosis - Painless, soft, diffuse, non-tender enlargement of parotid glands may be associated with diabetes mellitus, cirrhosis, hyperlipoproteinemia, anorexia nervosa (b) Sarcoidosis - May