Mutation of Yellow Fever Virus May Be Responsible for Outbreak in Brazil

05/16/2017 - 11h36

Researchers from the Owsaldo Cruz Institute have discovered that the virus from the latest outbreak of Yellow Fever in Brazil - the largest since the Health Ministry began record keeping - has a genetic sequence that has never been encountered before.

Motivated by the extent of the current epidemic, they performed a complete genetic sequencing of the genome of the virus and discovered eight mutations that had never been seen before in some of the genetic sequences.

Seven of the variations impact the formation of proteins involved in the replication of the virus, part of the process that allows the virus to inflict the disease.

It is possible that this genetic difference is one of the reasons for the latest outbreak, but researchers caution that it could also be explained by the fact that the population in the affected region (primarily Minas Gerais, Espírito Santo, São Paulo and Rio de Janeiro) has little vaccination coverage.

"We still don't know if this virus is predominant in the current outbreak. We have to conduct new studies", said Ricardo Lourenço, head of the Hematozoa and Transmission Mosquitos Laboratory of the Oswaldo Cruz Institute.

The country has registered 756 confirmed cases of the illness in 2017 so far, compared to seven in all of last year. Out of these, 259 have already resulted in deaths.

Even considering this discovery, scientists say that the vaccine currently in use continues to be effective.

This is because the changes don't affect the proteins that envelop the virus, which are the centers for the efficacy of the immunization.

Translated by LLOYD HARDER

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