Protesters brought Brazil's main highways nearly to a standstill amid persistent public anger over alleged misuse of public funds and neglect of basic services.

Brazilian President Dilma Rousseff faces a sharp drop in her approval ratings amid allegations the government has lavished funds on controversial prestige projects that should go toward poverty reduction and improving public services.

The prestige projects include multibillion-dollar sprucing up of the country's exterior image before next year's FIFA World Cup tournament and the Olympics in 2016. Critics accuse the government of turning a blind eye to mass-scale misappropriations, delays in projects and cronyism.

The government says the expenditure is necessary to prepare Brazil for the two international events. Media reports cite shortfalls in necessary infrastructural renewal, including hotel room shortages.

Rousseff launched a major anti-corruption drive last year amid charges of misrule by her predecessor, Luiz Inacio Lula da Silva, and his alleged cronies, but the campaign has been derailed as renewed allegations emerge of widespread graft under her own presidency.

Tens of thousands of protesters turned out for Thursday's demonstrations, with protesters and traffic clogging major highways in at least seven states, officials said.

Protest leaders called the turnout a "national struggle day." Although the main protests were orchestrated by trade unions, many other organizations joined in.

Access to the Santos port, the largest in South America, was blocked by protesters for a second day.

The country's heavily congested ports suffered more setbacks in authorities' desperate bid to clear a backlog that has spread panic among traders. Exporters fear they face huge losses as merchandise remains unshipped.

Disruptions were reported in hospitals and some schools remained shut. Public transport systems in many areas outside Rio de Janeiro and Sao Paulo were hit, leaving thousands more who didn't join the protests stranded in roads and at railway stations.

As the protests spread, demands have widened, too. Protesters want specific action on improving infrastructure, reducing income disparities and agricultural reforms that can lift farmers out of chronic poverty.

Analysts say income disparities have worsened with rising inflation.

IMF data show emerging markets including Brazil face slowing growth. The IMF cut its global growth forecast for 2013 to a "subdued" 3.1 percent and for emerging economies to 5 percent from 5.3 percent.

The outlook for Brazil has gone down to 2.5 percent from 3.4 percent.

Critics say the slow growth forecast is another reason for the Rousseff administration to be more cautious with public spending.