Brazil’s health ministry launched a nationwide vaccination campaign on Monday to protect children from measles and poliomyelitis.

The initiative follows a measles outbreak that has affected more than 1,000 people and killed five children, coming shortly after the disease was eradicated in 2016. Health officials also worry that polio may return to Latin America’s largest nation.

The measles cases are mostly concentrated in northern states of Amazonas and Roraima where thousands of Venezuelan refugees are crossing the border to flee economic and political hardships, as well as a failing health system. Many of them are sick and haven’t been immunized.

“If our population in the north, which welcomed such a large group of Venezuelans, had been vaccinated, we wouldn’t be dealing with an outbreak right now,” said Isabella Ballalai, president of the Brazilian Society of Immunization. “We’d be dealing with a minor problem.”

That was the case from 2000 to 2013, when most Brazilians were protected against the disease, and stopped any imported measles viruses from spreading. But last year, only 70 percent of the population received both doses of measles vaccinations.

In the states with the most critical situation, the Ministry of Health has already been giving out free shots in clinics and home visits since July.

Now it wants to go back to full coverage on a national level: The goal is to vaccinate at least 95 percent of children aged 1 to 5 by the end of the month.

The Ministry of Health has been advertising the campaign for weeks, and even recruited popular children’s entertainer Xuxa – known as the “queen of the little ones” in Brazil – to be the celebrity spokesperson.

On the first day of the campaign, lines at Rio de Janeiro health clinics were relatively short.

There are only 14 confirmed measles cases in the region, but some families ventured into the rain to make sure their children were protected.

The 34-year-old teacher Michelle Souza brought her 2-year-old son Morilo to a center in Cidade de Deus in western Rio.

“I got really worried because it’s been a while since we heard anything about measles. And now the disease is spreading in some regions,” she told The Associated Press.

On the other side of the city, Ednea Fernandes, a 39-year-old seamstress, brought her son to the immunization clinic in Botafogo even though the 5-year-old had already gotten all his shots.

“I’ve always careful. But with this measles outbreak on the news, I’ve been especially vigilant,” she said. “They said I could take my son home.”

Turnout in the beginning of vaccination campaigns is often low in Brazil, but Ballalai hopes that awareness about the outbreak will keep growing, and that families will take their children to get vaccinated. On Aug. 18, the high point of the campaign, more than 36,000 clinics will be open.

“In previous campaigns, there wasn’t necessarily that call to save your child. So people didn’t show up,” she said.

“This time we’re calling out: Come save your child. Come save Brazil from measles.”

(AP)