Some people have felt series of complications related to the dreaded Zika virus and this has been linked to the sudden surge of microcephaly cases in Latin America. Now, there's another reason to fear this mosquito-borne illness since the virus could mutate rapidly, a new study found.

A team of researchers from the University of California, Los Angeles (UCLA) and the Chinese Academy of Medical Sciences and Peking Union Medical College have tracked down some genetic mutations that happened in the Zika virus. They hope to finally explain why the virus had suddenly caused birth defects since its outbreak in 2015.

The findings of this new study support what other scientists claimed in the past. The strain of the virus that ravaged Latin America and the Caribbean over the past couple of months is not the same strain of virus observed in Africa. The latter strain is harmless and had not caused the same complications seen among babies born to mothers infected with the virus.

The virus that has been dubbed an international public health emergency by the World Health Organization (WHO), emerged from a strain that circulated in Asia before going across the Pacific, the researchers found.

Mutation seems like bad news especially when it comes to pathogenic microorganisms. These microbes could cause a wide range of infections and once they mutate, current effective drugs and therapies might not work anymore. The worst thing is, mutation makes them more resistant, robust and stronger.

"The Zika virus has undergone significant genetic changes in the past 70 years," said Genhong Cheng, professor of microbiology, immunology and molecular genetics at UCLA's David Geffen School of Medicine.

"By tracing its genetic mutations, we aimed to understand how the virus is transmitted from person to person and how it causes different types of disease," he added.

Aside from being linked to the increased number of babies born with microcephaly — a birth defect causing the baby to be born with a smaller head and brain damage — it has also been associated with a form of paralysis called Guillain-Barre syndrome. New modes of transmission including infection through mother-to-fetus and sexual intercourse have also emerged.

The scientists said they are not sure why the virus has not been linked to serious diseases in the past, not until now.

They compared individual differences in genetics among 41 Zika virus strains — 30 strains from humans, 10 from mosquitoes and one from monkeys.

Along the process, they identified DNA changes between the strains, showing major differences between the African and Asian strains. There were also differences between mosquito and human strains.

The mutations could help the virus to divide more efficiently, allowing them to escape the immune system of the body and invade new tissues that could provide them a shelter for them to spread.

The researchers hope to soon analyze the viral strains in order to look for genetic targets for the development of drugs and vaccines.

The study was published in the Cell Press journal, Cell Host & Microbe.