In many parts of the world, the number of measles cases has risen sharply, particularly in sub-Saharan Africa. The United States is also affected by this increase.

Measles cases worldwide have almost tripled since January compared to the same period last year, the WHO said Tuesday. Figures published by the World Health Organization show that from January 1 to July 31, 364,808 cases were recorded, against 129,239 last year at the same time. These are the "highest" figures ever since 2006, said a spokesman for the WHO, Christian Lindmeier, during a press briefing in Geneva.

The largest numbers of cases were recorded in the Democratic Republic of the Congo, Madagascar and Ukraine. In Magadascar, "the number of cases has, however, decreased significantly in recent months" following national measles vaccination campaigns, WHO said. Other major outbreaks are underway in Angola, Cameroon, Chad, Kazakhstan, Nigeria, the Philippines, South Sudan, Sudan and Thailand. The United States has had the highest number of measles cases in 25 years.

One of the most contagious diseases in the world

Measles is one of the most contagious diseases in the world and deaths are most often due to complications. There is no curative treatment, but it can be prevented by two doses of a "safe and highly effective" vaccine, according to WHO.

The largest measles epidemics occur in countries with low measles immunization coverage. In Western countries "anti-vax" relies on a 1998 publication linking the measles and autism vaccine. The WHO has repeatedly dismissed these criticisms and it has been established that the author of the publication, the British Andrew Wakefield, falsified his results. Mistrust may also have religious motives, as in New York where the disease was imported by unvaccinated travelers from Israel.