BRASILIA, Brazil: Brazilian public health officials are working to stop an outbreak of yellow fever that has killed at least 40 people in Brazil from becoming an epidemic, urging people to seek vaccinations in nine of the country’s 26 states.

The Health Minister said on Tuesday that 70 cases of the fever and 40 deaths have been confirmed in the outbreak centered in rural areas of the state of Minas Gerais, while another 47 deaths and 368 suspect cases are under investigation.

That is up from just seven cases last year and the highest number since 2003.

Yellow fever is a viral disease found in tropical regions of Africa and the Americas that mainly affects humans and monkeys and is transmitted by the same type of mosquito that spreads dengue and the Zika virus.

The outbreak comes as Brazil continues to battle Zika that has led to a spike in babies being born with microcephaly, a condition marked by an abnormally small head and often resulting in grave developmental issues.

Yellow fever is a viral disease found in tropical regions of Africa and the Americas that mainly affects humans and monkeys and is transmitted by the same type of mosquito that spreads dengue and the Zika virus.

Most people recover after the first phase of infection that usually involves fever, muscle and back pain, headache, shivers, loss of appetite and nausea or vomiting, the WHO says.

Health officials have distributed 4.9 million yellow fever vaccines since the start of the year.

In states where inoculation is recommended, Brazilians rushed to get a shot and public health centers ran out of vaccines.

In Brasilia, the capital, the death of one person suspected of picking up the virus in nearby Minas Gerais was being investigated, and inhabitants had to queue up for three hours in some cases to get vaccinated.

Brazil has never managed to entirely eradicate rural yellow fever, but it has not registered cases of the disease in urban areas since 1942.

The South American country recommends that visitors from abroad get vaccinated for yellow fever.