MUST READ: Heat wilting Rio de Janeiro Carnival street parties

RIO DE JANEIRO -- The hottest temperatures in five decades were melting Carnival revelry Tuesday after five days of dancing, drinking and smooching.

''I never thought I would say this, but it is too hot to party,'' said 20-year-old Thiago Cerveny, standing on a corner with his girlfriend in Ipanema and debating whether to hit a big street party on the last full day of festivities.

Rio's summer has seen record highs of up to 110 F. Couple that with the seaside city's suffocating humidity and the chances that partiers will fall ill increases.

It was 106 F Tuesday.

Dr. Luis Fernando Correa took to the Globo television network to warn those still partying to ''drink a lot -- but nothing alcoholic.''

Taking the booze out of what Brazilians call the world's biggest bash is certainly a challenge. Health officials said more than 1,400 revelers have been treated since Saturday, the majority for heat-related illness.

''During Carnival people go out in the street, they party, they forget to hydrate and even take medications they may need,'' Correa said. ''People, drink water!''

The withering temperatures punished participants in Rio's Carnival parades Monday night, many wearing heavy, elaborate costumes.

Geisy Arruda, a 20-year-old student who gained fame when she was expelled in October from her school for wearing a miniskirt, succumbed to the heat toward the end of her 80-minute appearance on a parade float.

She was seen tugging at her Carnival dress -- a flashy version of the garment that got her thrown out of school -- and had to lie down and ask for water. She rested and recovered.

Other Carnival queens, some with massive headdresses and elaborate wings of feathers harnessed to their backs, slumped down atop massive floats and asked people 30 feet below to throw them bottles of water.