Measles

Bug Type

Measles is an negative sense RNA virus from the Paramyxoviridae family, genus Morbillivirus, one of the most infectious viruses known.

Origin

Likely evolved from rinderpest (cattle virus). First descriptions from ancient China and Middle East.

Transmission

Airborne — the virus hangs in the air for 2 hours; spreads by breathing contaminated air, not just droplets.

Contagiousness

R0 = 12–18 → 90% of non-immune contacts get infected.

Invasion Mechanism

Enters respiratory tract, infects immune cells, travels through blood → rash appears as immune system reacts

6. Early Symptoms

Fever, cough, conjunctivitis, photophobia, runny nose.

7. Classic Symptom

Koplik spots inside cheeks — tiny white/blue lesions

Rash Pattern

Starts on face, spreads downward over entire body.

How It Kills

Severe immune suppression → pneumonia, encephalitis, secondary infections.

Treatment

Supportive only: hydration, fever control, Vitamin A improves survival in children.

11. Vaccine

Live-attenuated MMR (1960s). Strong lifelong immunity.

12. Is the science accurate?

Yes — one of the most successful vaccines ever created.

13. Important Scientists

Thomas Peebles (isolated virus), John Enders (vaccine), Peter Panum (lifelong immunity discovery).

14. Why outbreaks return

Vaccine hesitancy due to Wakefield’s false autism study.

description of virus

a pleomorphic, enveloped virus with a helical nucleocapsid, meaning its shape varies but it is generally spherical and has a lipid envelope surrounding an RNA and protein core