Mon | Jan 22, 2018

Microcephaly not new to Jamaica - CMO - Questions surround its link to ZIKV

Published:Wednesday | February 17, 2016 | 12:00 AMJason Cross
Cassiana Severino holds her daughter Melisa Vitoria, born with microcephaly at the IMIP hospital in Recife, Pernambuco state, Brazil last month
Lara, who is less then three months old and was born with microcephaly, is examined by a neurologist at the Pedro I hospital in Campina Grande, Paraiba state, Brazil, on Friday
Acting chief medical officer Dr Winston De La Haye.

Microcephaly is not new to Jamaica, noted Dr Winston De La Haye, acting chief medical officer in the Ministry of Health.

"In every country you have occurrences of microcephaly as one of the potential outcomes of defects of birth in children. And Jamaica, like any other country, we've had cases," De La Haye told The Gleaner.

According to data, throughout the period 2009 to October 2015, Jamaica had 35 recorded cases of microcephaly. There were a total of six cases in 2009; 10 in 2010; four in 2011; seven in 2012; six in 2013; and one case each in 2014 and 2015.

Due to the outbreak of the mosquito-borne Zika virus (ZIKV) in more than 26 countries, including Jamaica (with one reported case), serious concerns have been raised about the virus's link to microcephaly - an abnormal growth of the brain and stunting of the growth of the head of the foetus, arising from infection in the first months of pregnancy. Babies who develop microcephaly in the womb may not live to full term, may be born prematurely, may be still born or may survive, but with life-long disability.




Brazilian national authorities estimate that up to a 1.5 million cases of Zika-virus infection have occurred since the outbreak began. At the end of January, the Ministry of Health of Brazil reported 4,783 cases of microcephaly and/or central nervous system malformation, including 76 deaths since January 2015.

However, increasing concerns are being raised in numerous international quarters about whether there really is a link between the Zika virus and microcephaly. Many experts have been expressing the view that the virus is not to be blamed for the abnormality, and instead have blamed other factors.

In fact, the World Health Organisation (WHO) is still careful about making any direct link.

"Although a causal link between Zika infection in pregnancy and microcephaly has not, and I must emphasise, has not been established, the circumstantial evidence is suggestive and extremely worrisome," WHO general director, Margaret Chan, announced last month.

The risk of babies being born with microcephaly has raised alarm among women, particularly those who are pregnant or planning to become pregnant. There are many unknowns regarding the possible causes of microcephaly. WHO has proposed that until more evidence comes to light, there are ways that women can protect themselves from Zika virus infection.

Microcephaly is the medical condition characterised by an abnormal smallness of the head and underdevelopment of the brain, and is linked to a number of viral and bacterial infections including cytomegalovirus (CMV), toxoplasmosis, syphilis, rubella and the Zika virus.

Children with Microcephaly require, in most cases, specialised care for life, due to the underdevelopment of their brains and have significant effect on almost all other aspects of body functioning. They may also develop mental disability, delayed motor and speech functions, facial distortions, seizures and difficulty with balance and coordination.

De La Haye said Jamaica's health ministry has no new information on microcephaly's link to ZIKV than previously reported, but research is being conducted to detect any new developments. He also said new cases of microcephaly that may arise in Jamaica will have to go through statistical procedures before Zika virus can be determined as the cause.

"As it is now, it's what we call a temporal association, which means, a factor X happens at a time B. Sometime following that, you notice a particular phenomenon, in this case microcephaly. It doesn't mean it's a cause, so then you need to, using statistical methods, determine what the exact relationship is," he said.

"What you must factor in is the term they use in statistics, confounders. You want to statistically rule out those other causes before you can say it's ZIKV".

According to De La Haye, the advice to delay pregnancy for the next six to 12 months still stands. Women who are already pregnant are being asked to take extra precaution against mosquito bites.

"Internationally, a number of countries, and we're one of them, are recommending that women delay their pregnancy. Again we say anywhere from six months to a year, but that's not hard and fast either, I mean, as we go along and the research comes out, we'll know more, to be more specific about the time. As the research comes out, we'll be able to say how long it will take for you to feel safe. It's a general figure. We don't have any scientific evidence to support specifically the 12, but we think that's wise," De La Haye said.

A document on microcephaly is being prepared by the health ministry and will be made available to the public once completed, De La Haye shared.

Spread mainly by the Aedes aegypti mosquito, WHO has officially declared the Zika virus a public-health emergency of international concern, and officials are carefully monitoring the rapid spread of the virus. Scientists are working to develop a vaccine.