measles complicated with keratoconjunctivitis

例句：

1. 1. The measles virus is highly contagious and can spread quickly among people.
   麻疹病毒极易传染，可以在人群中迅速传播。
2. 2.Children are more susceptible to measles than adults because they have not yet developed immunity.
   儿童比成人更容易感染麻疹，因为他们还没有形成免疫力。
3. 3. In recent years, there has been a decrease in the incidence of measles in many countries due to vaccination efforts.
   近年来，由于疫苗接种工作的努力，许多国家的麻疹发病率有所下降。