The Gauteng health department is to roll out a "massive" measles immunisation campaign next week after 400 cases of the disease were reported in the province since March.

In a statement on Friday, the health department said the campaign would target children from six-months-old to primary and high school students.

Health workers would be going to schools, creches and schools throughout the province to immunise youngsters against the highly contagious but "less lethal" viral disease.

"As another measure to ensure that the disease is contained, the department's Outbreak Response Team has alerted all clinicians, both in the private and public sector, to be on the lookout for any signs and symptoms from patients who present themselves at the health facilities."

Infection control officers at hospitals have been asked to be on high alert for the disease, while health promoters are also focusing on measles.

The symptoms of measles include a runny nose, cough, red eyes, fever and rashes.

The first cases in the country were reported around March and these involved children from as young as four months to 56-year-old adults.