Researchers believe the infection prevents the stem cells to become neurons
A recent study conducted by scientists at the Federal University of Rio de Janeiro (Universidade Federal do Rio de Janeiro - UFRJ) revealed that the mosquito-borne Zika virus, which has been linked to a surge in cases of birth defects in Brazil and has spread in several countries, is the result of a mutation, a new type of virus, more dangerous and more aggressive than the one first identified in Uganda in 1947.
According to the study, the virus stops embryogenesis, the process of cell division and cellular differentiation of the embryo that occurs during the early stages of development, in which embryonic stem cells become many types of body cells. The infection prevents the stem cells to become neurons, the brain cells. Without neurons multiplication the brains of the babies don’t grow, what is known as microcephaly. There are also babies born with a normal brain perimeter, but with many alterations and destruction of the brain tissue.
“There were some mutations that made it capable to invade people’s central nervous system easily. The African virus infects and destroys the cell and doesn’t change it, while this virus changes the cell differentiation.” says virologist and UFRJ’s researcher Amilcar Tanuri.
The study indicates that the mutation of Zika virus is still not explained completely, but may explain why there was an increase of microcephaly cases in Brazil.
According to Tanuri, the virus has become much more capable to spread in the environment. “Maybe, in addition of giving the virus the ability to enter in the nerve tissues easily, these new mutations gave it also the ability to easily infect the mosquitoes.”
In Brazil, there were 6.776 suspect cases of microcephaly, 130 confirmedly related to zika virus, and 47 baby deaths. The Zika virus has now affected all the regions of Brazil and has spread to countries in South America, Central America, Mexico and the Caribbean.