The National Ministry of Health for this two states of Argentina (Rorama, Amapá, Amazonas, Pará, Acre, Rondónia, Mato Grosso, Mato Grosso do Sul, Maranhão, Tocantins, Goiás, Sao Paulo) Paraná, Santa Catarina, Rio Grande do Sul, Piauí (West and the South), Bahia, Minas Gerais, Espíritu Santo and Rio de Janeiro) at least 20 days before leaving fever.
Thanks to this recommendation, the demand for these doses in Buenos Aires has increased in recent days. In Misiones, although the yellow fever's demand was boosted, it was not significant. For some reason, 96% of the population of the province is against this disease. It is worth mentioning that the vaccine certificate is not a request for access to Brazil. Travelers from Paraguay to Brazil or Brazil must check their vaccines, requesting the Paraguayan authorities.
Ten years or so every time?
Before every year, before 2016, fever is recommended for boosting the vaccine. However, starting in January, the World Health Organization (WHO) decided the validity, issued and new certificates of all general strike vaccines, the whole life of the vaccine from the age of 10.
The WHO provides information on tourists about the need to prevent the spread of diseases of the liver and other vectors. (Https://www.argentina.gob.ar/sites/default/files/0000001383cnt-2018-11_ith-country-list-nov-2018.pdf). For tourists over nine months who want to travel to Argentina, WHO recommends that the vaccine be placed in yellow fever in the provinces of Corrientes and Misiones.
In Brazil, the transmission of yellow fever spread in the last three years: it began in the north and spread from east to south, especially in the Central West. The cases registered in the 2016, 2017 and 2018 cases have exceeded the cases in the last 50 years.