RIO DE JANEIRO (AFP) - Brazil's social turmoil over poor public services and endemic political corruption appears to have abated but could flare again during Pope Francis' visit later this month, analysts warn.

The unrest - which brought more than a million Brazilians onto the streets and rocked Latin America's economic behemoth for three weeks during the Confederations Cup football tournament - "surges up and down like a wave," said Paulo Henrique Martins, president of the Latin American Socoiology Association.

"This wave will roll as long as the Brazilian people mobilise on social issues," he told AFP.

Demands have focused on tougher measures to root out political corruption and greater investment in public transport, health and education - rather than in sporting events like the Confederations Cup and next year's World Cup.

Fewer people are hitting the streets to vent their anger, though truck drivers blocked roads across the country in a protest early this week and doctors demonstrated against the government's plan to attract foreign doctors to work in underprivileged areas.

But Pope Francis is due in Rio for the July 22-28 Catholic World Youth Day (WYD), an event expected to attract two million people, and this could tempt larger swaths of demonstrators to launch a new round of protests.

"New demonstrations could take place during WYD, an event that turns the global spotlight on the country and mobilizes its social structures," said Mr Martins.

Brazilians now realize that they can express their indignation, hold the government accountable and yield results, said anthropologist Alba Zaluar, of the Federal University of Rio de Janeiro.

Politicians have taken notice of "people power" and will be more cautious, he added.

"There will now be a waiting period, to see what happens, and if the political class fails to give an adequate response, the protests are likely to resume, even though on a smaller scale."

President Dilma Rousseff, whose approval rating plummeted 27 points to 30 percent after three weeks of unrest, according to a Datafolha poll, heard the "voices of the street" and, in response, pressed Congress to organise a plebiscite on political reform.

"If the government manages to translate the wave of mobilizations into (effective) public policies, it will be able to capitalize on them for the president's re-election" in October 2014, according to Mr Martins.

But a lot remains to be done, judging by the succession of scandals in Congress where many members have been accused of or convicted for various offenses.

The latest came to light Wednesday with revelations the speaker of the House of Deputies, Henrique Eduardo Alves, had used an air force plane to fly his family to Rio to attend Sunday's final of the Confederations Cup between Brazil and Spain.

"In today's Brazil, there is too much caviar for the elite - and the people have noticed," journalist and author Elio Gaspari wrote in a recent New York Times column.

"That realisation, along with outrage at widespread corruption, has helped the current outcry cross class, party and generational lines."

Mr Martins, joining with other intellectuals in French newspaper Liberations, compared the upheaval in Brazil to the mass protest movement Occupy Wall Street and the Arab Spring.

"What is being denounced (in Brazil) is the growing abyss between the rulers and the ruled, the richest and the poorest," Mr Martins wrote.

Pablo Soares Goncalves, of the Catholic University of Rio de Janeiro, meanwhile noted that the recent protests had overshadowed the Confederations Cup.

"The fact that football did not dominate conversations during the Confederations Cup is very interesting," Mr Goncalves said.