Zika virus and pregnant women: recommendations

Zika virus and pregnancy: we take stock

A brief reminder of the facts

Since 2015, a strong epidemic of the Zika virus affects Central and South America. Identified since 1947 in Sub-Saharan Africa, the virus settled in Polynesia in 2013 and would probably have reached the American continent in 2014, during the football world cup in Brazil. It has now been identified in other countries on the continent such as Peru, Venezuela, Colombia, Guyana, the West Indies and even Mexico. On February 1, 2016, the World Health Organization (WHO) declared the Zika virus to be ” a global public health emergency ».

This disease is indeed likely to be transmitted sexually, even through saliva, and especiallycause brain malformations in fetuses exposed to the viruss. We took stock of the situation with Dr Olivier Ami, Secretary General of the National Professional Council of Gynecology and Obstetrics (CNPGO).

Definition, transmission and symptoms of Zika virus

Zika virus is a flavivirus from the same family as the dengue and yellow fever viruses. It is carried by the same mosquito, that is to say the tiger mosquito (genus Aedes). A single bite can be enough to contract this virus, provided the mosquito is a carrier.

What makes the detection of the virus all the more difficult is that it can be asymptomatic (in more than 3/4 of cases), and not trigger any particular sign. When symptomatic, the virus causes flu-like symptoms, such as fever, muscle and joint pain, malaise, headaches, skin rashes or even conjunctivitis. Most often mild, these symptoms disappear between 2 to 7 days after contracting the virus. Unfortunately, in pregnant women, this virus is susceptible toaffect the brain development of the fetus, this is why pregnant women should be particularly supervised.

On the diagnostic side, it is based on a simple blood test or a saliva or urine sample in which we will look for traces of the virus, more precisely its genetic heritage. But obviously, only the presence of symptoms will push medical teams to suspect the virus. If the latter is present in an individual, then doctors may decide to culture the virus in a laboratory to measure its infectious potential and learn more about its dangerousness.

Zika and pregnancy: a risk of fetal malformation

At present, it is no longer a question of whether or not the Zika virus is indeed the cause of the cerebral malformations observed in exposed fetuses. ” The Brazilian authorities have launched an alert, on the recommendation of doctors, because they have declared and identified an abnormal number of cases of children with small head circumference (microcéphalie) and / or brain abnormalities visible on ultrasound and at birth Says Dr Ami. On the other hand, “ there is no certainty as to the number of proven microcephaly. This cerebral anomaly is all the more worrying as it is linked to mental retardation “ The smaller the cranial perimeter, the greater the risk of mental retardation ”, explains Dr Ami.

However, the Secretary General of the CNPGO remains cautious: he considers thata cranial perimeter in the lower limit should not lead to consider that the child will necessarily have a mental retardation, since the very definition of microcephaly is not clear. Likewise, it is not because a pregnant woman has Zika virus that she will inevitably pass it on to her baby. ” Today, when a pregnant woman contracts the Zika virus, no one can tell the percentage of risk that she will transmit it to her baby. No one can say either what is the percentage risk that the infected fetus will develop microcephaly.. “Clearly, at the present time,” we just know that something is happening and thataction must be taken to reduce the exposure of pregnant women », Summarizes Dr Ami.

Zika and pregnancy: precautions to take

In view of the possible risks to the fetus, it is obvious that the precautionary principle is in order. The French authorities therefore advise pregnant women not to travel to areas where the virus is present. Women living in these so-called endemic areas are also advised to postpone their pregnancy plan as long as the virus is there. In addition, as in all mosquito-borne epidemics, it is advised to use mosquito nets and repellents if you travel to the countries concerned.

What examinations after a stay in a risk zone while being pregnant?

According to Dr Ami and the entire National Professional Council of Gynecology and Obstetrics, it is fashionable to consider anyone returning from an area endemic to the Zika virus as potentially affected.The Institut Pasteur is in the process of setting up with the High Committee of Public Health to help practitioners know whether or not to test for the presence of the virus in their patients, depending on the country visited and the return date.

For pregnant women returning from a stay in an endemic area, the CNPGO recommends that practitioners perform Zika virus serology and set up close monitoring in case of doubt, in measuring the head circumference of the fetus at each ultrasound. « This simple measurement will make it possible to observe or not the presence of what we fear, that is to say the appearance of a malformation or, in any case, not to miss it. », Emphasizes Dr Ami.

Zika and pregnancy: what to do in case of proven infection?

Unfortunately there is no no specific treatment against Zika virus at present. Likewise, there is currently no vaccine to curb the epidemic, even if research is working to find one as soon as possible.

Also, if a person has contracted the virus and is showing symptoms, it will simply be a matter of setting up symptomatic treatment. Analgesics will be prescribed for headaches and pains, medicines for itching, etc. There is, however, no way to prevent the infected person from getting all of these symptoms. For a pregnant woman, it’s a bit similar: there is no currently known way to prevent her from transmitting the Zika virus to her baby.

The procedure will consist of trying to assess the risk of microcephaly for the baby and watch for signs of this abnormality. When a pregnant woman is affected, she should be followed in a multidisciplinary prenatal diagnostic center, where the medical team will perform regular diagnostic ultrasounds. When the infection is proven, “ it’s not just the head circumference to watch »Says Dr Ami. ” There are also the eyes (presence of microphtalmie) and the brain. We will check the absence of calcifications, which precede the onset of brain damage, the absence of cysts or cortical abnormalities. However, these screenings are not among those usually performed in an office. »

Zika and pregnancy: an amniocentesis to check for the presence of the virus

To consolidate the diagnosis, Dr Ami points out that an amniocentesis can also be performed. ” We will try to demonstrate the Zika virus in the amniotic fluid by amniocentesis, but only if the pregnant woman herself is infected and her child has brain abnormalities on the ultrasound », He explains. ” If she transmits it to her child, the latter will excrete the virus in the amniotic fluid, especially between the 3rd and 5th day following the infection. As the amniotic fluid is a rather closed environment, we can find traces of the virus a few days, even a few weeks later. He continues. ” This confirmation will make it possible to identify the rate of anomalies observed and linked to this virus. ”, Which will advance research.

If the medical team is virtually certain that the child has a high risk of mental retardation, the couple may request a medical termination of pregnancy, a procedure authorized in France under certain conditions, but which remains prohibited in many affected countries (notably in Brazil). In France, this should be accepted without problem if the mental retardation is proven in view of the abnormalities observed on ultrasound. Dr Ami specifies that children born with microcephaly ” have an approximately normal life expectancy, almost normal social interactions, but a motor delay which complicates, among other things, the acquisition of walking and speaking. »

Zika and pregnant woman: what about breastfeeding?

« Currently there is no reason to ban breastfeeding in a woman, even if she is infected Says Dr Ami. ” To date, there are no published cases of severe forms of Zika virus infection in infants or young children. The virus will cause them the same symptoms as in adults, but no problem with brain malformation since the brain is already formed He continues. In addition, Dr Ami stresses that it is not certain that the Zika virus, if it is present in breast milk, has an infectious power. ” What if a woman gets the virus after giving birth while breastfeeding, the risks to the baby’s brain seem almost nil, according to the first elements which emerge from the scientific literature. “So there is” no reason to prohibit breastfeeding for women with this stage », Concludes Dr Ami.