Medicine

Zika: How does a Virus into the brain

Researchers have the Zika Virus in the brain of babies with Schädelfehlbildung found. How does a Virus the way to this sensitive and well-protected place? Virologist Herbert Pfister provides the answers.

In the Brazilian Rio is now probably for the first time since the outbreak of Zika Virus to a fetus in the womb of the infection died. Also, the connection between the Virus and the Schädelfehlbildung Mikrozephalie is clear. So, several of you have been Reborn with a too-small head, the Zika Virus, has been detected.

DW: now, Is that the evidence that Zika actually Mikrozephalie – so Schädelfehlbildungen – leads?

Herbert Pfister: We have this parallel development – an outbreak of Zika infection and an accumulation of Mikrozephalie cases. Such parallel developments are clear warning signs. Now you have the Virus is also found in the brain – that is a further component and the requirement that the Virus has a role in the Mikrozephalie plays. A confirmation is pending.

How is this actually a Virus into the brain?

There is a colourful bunch of viruses in the brain and then cause severe damages. The viruses come from either the blood or on the nerves. For example, the Herpes Simplex Virus and the rabies Virus through the nerves to the brain. And there are the viruses, especially by ticks and mosquitoes, and through the blood into the brain. In most cases, the Virus remains but in front of the brain depend. We are all the much more commonly infected, than that something really happens.

Herbert Pfister is Director of the Institute for Virology at the University of Cologne

How to protect the brain against these intruders?

The brain is a kind of high-security of the body. There, the blood-brain barrier. This is a barrier between the blood system and the interior of the brain. A Virus can be with the help of cells which are independently able to move, these barriers can be overcome.

Where to put viruses in the brain?

It creates the Virus in the actual brain, then one speaks of a case of encephalitis, a brain inflammation. Or it ignite the Gehirnhäute – that would be a Meningitis. Or the spinal cord can ignite. That would be the Myelitis, as the polio used to know. Everything in the Central nervous system runs out can be very dangerous. The most Harmless are the Gehirnhäute – since the Patient has a good chance.

The encephalitis has different types of the disease. A Herpes Simplex encephalitis ends up untreated in 70 percent of cases fatal. Who will survive, has heavy damage. The Myelitis from polio is well known, in the course of paralysis, and if the respiratory muscles is affected, that means death.

Now we know that the Zika Virus in the womb to the Unborn child transfers. There are more examples of such Transmissions of the virus to the Unborn?

A long known example is rubella. As, however, still is not vaccinated, was a Rötelninfektion in the early stages of pregnancy is a huge risk for malformations in the eyes, in the hearing and also in the brain. About half of the Germans are with the Cytomegalovirus, a Herpes Virus – infected. In a primary infection during pregnancy, the Unborn child is affected and cause severe malformations to the brain. These are the two well-known examples of an infection in the womb and now is probably the Zika Virus.

You can experience these diseases are also on the Zika Virus is transmitted?

For most viruses, there is no therapy such as Penicillin against bacteria. For many viruses, the to Gehirnentzündungen lead, there is no treatment. You certainly can’t make a lot to learn. You must first of all such infections.

Herbert Pfister is Director of the Institute for Virology at the University of Cologne.