A study confirmed that indeed Zika virus causes brain damage in newborn babies.
The result of the newly-conducted study confirms that microcephaly suffered by babies are caused by the Zika virus.
Microcephaly is a birth defect marked by small head size that can lead to severe developmental problems. The virus has since spread rapidly through Brazil, the Americas and Caribbean.
The study was published in The Lancet Infectious Diseases journal on Thursday.
This is based on the early results from a crucial case-control study in Brazil that have confirmed a direct link between Zika virus infection in pregnant women and the brain damaging birth defect microcephaly in their babies.
Despite of this, the researchers said the true size of the effect will become clear only after full analysis of all 200 cases and 400 controls subject to the study. As of now, they only saw the preliminary findings from the first 32 cases involved in the study confirm causality.
The said study was requested by the Health Ministry of Brazil to investigate the causes of the microcephaly epidemic.
The outbreak of Zika, a mosquito-borne disease, was detected last year in Brazil, where it has been linked to more than 1,700 cases of microcephaly, urging the country to conduct such research.
Earlier this year, the World Health Organization (WHO) declared an international public health emergency due to Zika virus.
The research was conducted by some professors and other staff who helped in the study.
Laura Rodrigues, a professor at the London School of Hygiene and Tropical Medicine who worked on the study, said its results were “the missing pieces in the jigsaw” proving the link between Zika and the condition.
The research followed and compared pregnancies that resulted in healthy babies with those that resulted in cases of microcephaly.
They looked for signs that the Zika virus is passed onto fetuses who develop the defect.
The studies covered all babies born with the said condition delivered in eight public hospitals in the state of Pernambuco between January 15 and May 2 this year. For each case, two controls were added. These were the first two babies born the following morning without microcephaly in one of the hospitals.
They took samples and conducted brain scans and the researchers found that 41 percent of mothers of babies with microcephaly tested positive for Zika infection in blood or cerebrospinal fluid samples, compared with none of those whose babies did not have microcephaly.
A high proportion of mothers of both microcephaly and non-microcephaly babies also tested positive for another mosquito-borne virus, dengue fever, as well as other infections such as herpes, rubella and toxoplasma.
“Our findings suggest Zika virus should be officially added to the list of congenital infections,” said Thália Velho Barreto de Araújo of Pernambuco University in Brazil, who also worked on the research team. “However, many questions still remain to be answered including the role of previous dengue infection.”