According to the World Health Organization (WHO), the number of measles cases reported worldwide tripled in the first three months of 2019 compared to the same period last year.
The UN Panel said preliminary data pointed to a "clear trend", with outbreaks occurring in all regions of the world.
In Africa, the most dramatic increase was 700%.
The agency said the actual numbers could be much larger, with only one in ten cases reported worldwide.
Measles are a highly contagious viral disease that can sometimes lead to serious health complications, including lung and brain infections.
Ukraine, Madagascar and India were hit hardest by the disease. Tens of thousands of cases were reported per million people.
Since September, at least 800 people have died of measles in Madagascar alone.
Outbreaks have also hit Brazil, Pakistan and Yemen and "caused many deaths – especially among young children".
In addition, an increase in case numbers was reported for countries such as the United States and Thailand with high immunization coverage.
The United Nations says the disease is "completely preventable" with the right vaccines, but worldwide coverage of the first vaccine phase has "stalled" in 85%.
In a commentary for CNN, WHO leaders Henrietta Fore and Tedros Adhanom Ghebreyesus said the world was "in the midst of a measles crisis" and that "the dissemination of confusing and contradictory information" about vaccines was partly to blame.
Why the sudden "global measles crisis"?
By James Gallagher, Health and Science Correspondent BBC News
It is one of the most contagious viruses, but measles has not changed. It does not mutate to become more contagious or dangerous, instead the answers are quite human.
There are two stories here – one of poverty and one of misinformation. In poorer countries fewer people are vaccinated and a larger part of the population remains susceptible to the virus.
This creates the environment for a major outbreak – in the Democratic Republic of Congo, Kyrgyzstan and Madagascar.
But even in the rich countries with seemingly high vaccination rates, cases are increasing. This is because groups of people decide not to vaccinate their children because false anti-Vax messages are being spread on social media.
It's worth noting that these numbers are preliminary, the WHO says the true numbers will be much higher. And measles is anything but harmless. It kills around 100,000 people every year, mostly children.
The couple wrote that it is "understandable in such a climate as loving parents can feel lost" but "ultimately there is no" debate "about the profound benefits of vaccines".
They added: "Since the year 2000 alone, the measles vaccine has saved more than 20 million lives."
In response to recent measles outbreaks, calls have been made in several countries calling for vaccination.
Last month, Italy prohibited children under the age of six from attending schools unless they had been vaccinated against chickenpox, measles and other diseases.
In the area of New York, a public health emergency has been called, condemning all residents for vaccination or a fine.