Altogether, in 2016, 30,273 cases of measles were reported in all 21 aimags. Globally, measles is still one of the leading causes of death for children less than 5 years of age, despite the availability of a safe and effective vaccine that prevents this deadly disease. In addition, studies have show'n that measles virus infection often results in pneumonia or diarrhoea, which contributes to the total number of children who die of causes related to measles.