Zika could cause more birth defects - study

  • 26/02/2016
Geovane Silva holds his son Gustavo Henrique, who has microcephaly, at the Oswaldo Cruz Hospital, Brazil (Reuters)
Geovane Silva holds his son Gustavo Henrique, who has microcephaly, at the Oswaldo Cruz Hospital, Brazil (Reuters)

As countries fight to wipe out the threat of the mosquito-borne Zika virus, researchers say it could cause more birth defects than just microcephaly, which leaves babies with abnormally small heads.

The possible wider effects are documented in a study published by researchers from the US and Brazil in PLOS Neglected Tropical Diseases today.

The study focuses on one 20-year-old pregnant Brazilian woman who had a stillborn baby in January. The baby had signs of severe tissue swelling as well as central nervous system defects which caused the cerebral hemispheres to be absent.

Her pregnancy through the first trimester had been normal, but that "changed abruptly" during her 18th week when an ultrasound discovered the foetus' weight was below where it should have been.

At that point she hadn't reported symptoms associated with Zika -- rash, fever or body aches -- before or during the early stages of her pregnancy.

She also didn't show signs of other mosquito-borne diseases such as dengue and chikungunya.

At week 30 of the pregnancy, the baby showed a number of birth defects and labour was induced at 32 weeks.

Researchers confirmed the baby had the Zika virus which appears to be the same strain which has led to the World Health Organisation declaring an international public health emergency.

Zika has been recorded in at least 20 countries including the Pacific nation of Tonga, Brazil, the US and throughout Latin America and the Caribbean.

The researchers, led by Albert Ko of the Yale School of Public Health and Dr Antônio Raimundo de Almeida at the Hospital Geral Roberto Santos in Salvador, Brazil, say the case provides evidence Zika can cause other birth defects.

A congenital Zika infection may also be linked to hydrops fetalis -- an abnormal accumulation of fluid in fetal compartments, hydranencephaly -- almost complete loss of brain tissue, and stillbirth.

They believe since it is likely large numbers of pregnant Brazilian women and those in other affected countries will be exposed to the same strain of Zika their case study was, more investigation is needed into the risk of stillbirth.