It has been more than two years since Brazil declared the Zika virus outbreak to be a public health emergency. Consequently, WHO declared a global health emergency the following year after the spread of the disease accelerated due to summer Olympics held in Rio de Janiero.

It was not until Zika-infected pregnant women began giving birth to babies with microcephaly, that the true horrors of the infection were realised. Extensive research was done on the probability of onset of microcephaly after birth, but it could not be determined how common delayed onset actually was.

In attempts to answer that, a new report by the US Centres for Disease Control and Prevention (CDC) examined the current condition of the infants born to mothers infected with the Zika virus two years ago. The first such study, was published in Morbidity and Mortality Weekly Report, a journal published by the CDC.

Lifetime care for Zika-infected babies

Conducted with the help of the Brazilian Ministry of Health, the study evaluated children from the epicentre of the crisis – the Paraiba state in Brazil. The researchers began with 278 babies, of which 122 of the families agreed to follow-up evaluations until finally the 19 most severely affected were included in the report.

The children, between 19 and two years old were assessed, and were found to have the cognitive and physical development of six-month-olds. Four were found to have been misdiagnosed with microcephaly whilst the other 15 had severely impaired motor skills and all except one met the conditions for a diagnosis of cerebral palsy.

Most had seizures and sleeping problems, eight suffered bronchitis or pneumonia and nine had enough difficulty eating or swallowing – which can be life-threatening if food gets stuck or the children are malnourished. Most could not sit up, had almost no language skills and had vision and audio problems that affected learning. They would need lifetime care, according to the authors.

“As children born affected by Zika virus grow up, they will need specialised care from many types of healthcare providers and caregivers,” Dr Georgina Peacock, director of CDC’s Division of Human Development and Disability, said in a statement about the findings.

Global scientific community scramble to find answers

Although it is no longer a worldwide emergency, the many detrimental effects of Zika remain unknown – despite the recent report – so, babies need to be continually monitored.

“It would be premature to think that the Zika pandemic is now under control and will not re-emerge, perhaps more aggressively,” say leaders from the US National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health.

The recent research only solidified the fact that the effects of Zika represent a “profound medical tragedy” and societal challenge that will require decades of financial, medical and social support, NIAID director Anthony S. Fauci, MD, and senior advisor David Morens, MD wrote in an introductory article for The Journal of Infectious Diseases published on 16 December.

Many researchers have contributed to the understanding of the disease, particularly in January this year, scientists from Harvard, MIT and the Austrian Academy of Sciences, developed a method called brain blobs. Derived from stem cells using CRISPR, the brain blobs will help researchers study how brains develop, and how Zika affects the brains of new-borns.

Similarly, in April, researchers were able to announce that they were entering Phase 2 of trials for a vaccine that protects against Zika. Subjects in the trial will be monitored for two years. Scientists also discovered that of the two main lineages of the virus – African and Asian – only the Asian lineage has been linked with microcephaly.

However, it has not all been positive. A study conducted at Washington University also found that Zika damages the male reproductive system. Dr Michael Diamond, head of the research said, "we saw significant evidence of destruction of the seminiferous tubules [of the testes], which are important for generating new sperm." While it has only been tested in mice so far, the implications for humans are worrying.

Low hopes for future of Zika-infected babies

“We need to keep working on this issue and we need to be trying to figure out what’s going on with these babies,” says CDC director, Dr Brenda Fitzgerald. Photo credit: Politically Georgia/Kent D. Johnson
“We need to keep working on this issue and we need to be trying to figure out what’s going on with these babies,” says CDC director, Dr Brenda Fitzgerald. Photo credit: Politically Georgia/Kent D. Johnson

Nearly 3,000 children were born with Zika-caused microcephaly in Brazil alone. Whilst it is still unclear how many of them will suffer severely, doctors across the country who have been treating the infants, do not have high hopes.

“It’s heartbreaking,” says CDC director, Dr Brenda Fitzgerald. “We would expect that these children are going to require enormous amounts of work and care.”

“Any babies that have this degree of microcephaly, we would not expect them to catch up,” Dr Cynthia Moore, chief medical officer in CDC’s division of congenital and developmental disorders said. “We can’t make predictions but we believe they’ll have lifelong challenges.”

The CDC aim to continue to monitor the children for years to understand the range of difficulties and see if problems develop for mildly affected children and children who appear normal. MIMS

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