Measles vs chickenpox ms..pptx agent, host, environmental transmission factors and clinical features.

This document summarizes key epidemiological factors related to smallpox, chickenpox, and measles. For smallpox, it notes factors that enabled its eradication like lack of animal reservoirs, effective vaccination, and distinctive rash allowing easy detection. For chickenpox, it outlines agent, host, environmental transmission factors and clinical features. For measles, it provides global burden, India statistics, epidemiological determinants like transmission via droplets, and prevention through vaccination or immunoglobulin administration.

1. Measles vs Chickenpox Prepared and Presented by Manjit kumar Mahato Bachelor in Public Health MBAHS, Hetauda

2. Feature Chickenpox Measles Causative Virus Varicella-zoster virus (VZV) Measles virus (a paramyxovirus) Initial Symptoms Mild fever, fatigue, and loss of appetite. High fever, hacking cough, runny nose, and red, watery eyes. Unique Symptoms General aches and pains may precede the rash. Koplik's spots: tiny grayish-white spots with reddish centers inside mouth. Rash Appearance Itchy red spots → fluid-filled blisters → burst, scab, and heal. Flat, red-brown spots that may merge into patches; rash usually not itchy. Rash Distribution Starts on chest, back, face, scalp → spreads across body, including mouth/genitals. Starts on face (near hairline, behind ears) → spreads downward.

3. Fig: Kopliks spot

4. Rash Progression New spots appear in “crops” over days → different stages (spots, blisters, scabs) visible at once. Rash appears/fades in a single wave, lasting 5–6 days. In fectivity Range from 1-2 days before the appearance of rash and 4-5 days thereafter Usually 4 days before and 5 days after the appearance of the rash. Secondary Attack Rate. Rare Infection confers lifelong immunity. Age primarily among children under 10 years of age. From 6 month to 3 years

5. Environmental Factors: First 6 month in year The virus can spread in any season. Incubation period: 14-16 days 10 days from exposure to onset of fever and 14 days to appearance of rash.

6. Stages: Pre-eruptive stage: Sudden onset with mild–moderate fever, back pain, shivering, malaise. Very brief (~24 hrs ). In adults: more severe, lasting 2–3 days before rash. Prodromal stage (Days 10–14) Fever, cough, runny nose, sneezing, red eyes, tearing, photophobia. Vomiting or diarrhea may occur. Koplik’s spots appear in the mouth 1–2 days before rash.

7. Stages Eruptive stage: In children, rash is often the first sign. Rash appears on the same day as fever. Eruptive stage: Dusky red maculopapular rash (flat + raised). Starts behind ears, spreads downward over 2–3 days. Rash may merge (confluent) and blotchy; lasts 3–4 days. Leaves brownish discoloration as it fades. Post-measles stage: Weakness, weight loss, slow recovery. Risk of growth retardation, diarrhea, secondary infections, TB reactivation.

8. Complications Usually mild; may include secondary bacterial skin infections, pneumonia, encephalitis, Reye’s syndrome (if aspirin used), and shingles (herpes zoster). Often severe; may include pneumonia, ear infections (hearing loss), encephalitis, subacute sclerosing panencephalitis , severe diarrhea, dehydration, immune amnesia, and risk of miscarriage or premature labor.

9. similarities in measles and chickenpox Similarities : Both are viral infections. Both are highly contagious. Both cause rashes. Both have fever and prodromal symptoms. Both primarily affect children. Both can cause complications in high-risk groups. Both usually provide immunity after infection.