RIO DE JANEIRO (AP) — Brazilian health authorities are urging Carnival visitors to stick to celebrations in the city of Rio de Janeiro and avoid heading out of town for sightseeing at waterfalls and forests where yellow fever has been detected. Rio state Health Secretary Luiz Antonio Teixeira Junior said on Tuesday that there have been no recent urban cases of the disease and that the risk of contagion in touristic parts of Rio is "nearly zero." "Visit our beaches, but avoid forests, bushes and waterfalls.