The initial manifestations of measles include:

First, fever usually moderate or higher, with varying patterns.

Second, symptoms of upper respiratory tract inflammation and conjunctivitis. Along with the fever, symptoms such as cough, sneezing, throat congestion, acute upper respiratory infections, conjunctival congestion, tearing, and photophobia can appear.

Third, measles mucosal spots, also known as Koplik's spots, are an early specific sign of measles. They usually appear one to two days before the rash, initially located on the buccal mucosa opposite the lower molars as gray-white spots with a diameter of 0.5-1mm, surrounded by a red halo. They rapidly increase in number, extending over the entire buccal and lip mucosa, and may merge. They disappear one to two days after the rash appears.

Fourth, other symptoms include general discomfort, decreased appetite, lethargy, and may also include vomiting and diarrhea.