Caracas - At least 70 children from an indigenous tribe have died from an outbreak of measles in a remote jungle region of eastern Venezuela, a human rights group said on Thursday."The propagation started in early January and we are calling for a health alert," said Armando Obdola, head of the Kape Kape NGO.Obdola said he had been recording the deaths in the state of Delta Amacuro, where children of the Warao indigenous community have been dying since the beginning of the year."There are no medicines, and there's nothing the doctors and nurses can do."Latin America was declared free of measles in 2016, but the Pan American Health Organization last month reported a virulent outbreak in Venezuela.The country has the highest number of confirmed cases, 159, among nine Latin American countries that reported cases in the first three months of 2018.The second biggest outbreak, in Brazil, has 14 confirmed cases, all of them imported from Venezuela."All confirmed cases were reported in unvaccinated Venezuelan citizens between the ages of nine months and 18 years," said PAHO.Measles, a highly contagious viral disease that affects children in particular, is preventable with vaccination.Venezuela's deepening economic crisis has caused chronic shortages of food and medicines.Access to affected areas are difficult. The Warao settlements are located on the edge of the Orinoco River, eight hours' travel from the regional capital Tucupita."Sometimes getting to a sick person is impossible. The boats do not have fuel, and despite the seriousness of the situation the silence of the authorities has prevailed," said Obdola.Venezuela's Health Minister Luis Loez said Tuesday on Twitter that the government of President Nicolas Maduro is fine-tuning details for the launch of a national vaccination plan for diphtheria, measles and yellow fever.