Skip to 0 minutes and 13 seconds Hello. My name is Beatriz Parra. I work as a teacher and researcher at the University of Valle. I have experience with viruses, immune response to viruses and diagnosis. We belong to a research network called NEAS. The acronym stands for “Emerging Neuro-virus in the Americas”. We aim to study the connection among mosquito borne diseases, such as dengue, Zika and chikungunya when related to neurological complications. Regarding Zika, I would like to emphasize that most infected people develop only a short-lived fever and a rash. This rash can be very irritating. In a few cases people develop neurological complications called “neuro-Zika”. One of them is Guillain-Barré syndrome. It affects the peripheral nervous system causing ascending paralysis in the extremities.
Skip to 1 minute and 21 seconds It can even compromise people’s lives when not treated. This treatment can be very expensive for health departments. Other neuro-Zika categories include direct brain damage, such as encephalitis and microcephaly in the womb. NEAS network is carrying out a research project aiming to establish the relationship between Zika infection and Guillain-Barré syndrome. Proving this relationship requires our identifying the virus in people suffering from that complication. In this laboratory, we provide tests to detect the infection. We detect the virus using molecular methods called “real-time PCR” or real-time polymerase chain reaction. It consists of amplifying, in vitro, the virus’s nucleic acid millions of times. This virus may be present in biological fluids, such as urine, saliva, blood… And cerebrospinal fluid in neurological cases.
Skip to 2 minutes and 40 seconds While the team amplifies the nucleic acid present in patients’ biological fluids a fluorescent curve indicates whether the results for the patient’s sample are positive or not. But it also indicates the number of copies found in that sample. What have been the important findings of this research to date? Most people suffering from Guillain-Barré complications including control groups of people infected with Zika who do not have the syndrome, eliminated the virus from their blood quite quickly. Approximately two or three days after the first skin eruptions the virus can no longer be detected in the blood. Interestingly, the virus continues to be excreted in the urine for several weeks after the infection has occurred. We think this is an important finding.
Skip to 3 minutes and 44 seconds These results are important, because urine is a biological sample you can obtain with non-invasive methods. It can represent an important sample to detect infection especially for complications occurring days or weeks after the severe symptoms of Zika have passed. It can also be quite useful to identify the infection among pregnant women once the virus has disappeared from the blood. The biological reasons why the virus is excreted in the urine as a result of its extended presence in the kidneys remain unknown. It could be contributing to physiopathology. Or it could be the consequence of a complication of the immune response which causes the virus to stay longer in the body.
Skip to 4 minutes and 42 seconds We aim to answer all these questions on immune response for Zika and about Zika virus itself. This research is conducted within the collaborative NEAS network which would then lead to better diagnoses of Zika virus. It would also help us manage patients better. But it would allow us, above all, to know and predict who will develop these neurological complications aiming for better prevention. Thank you.
Case study: exploring links with Guillain-Barré
In this step, Dr Beatriz Parra from the University of Valle highlights some of the research being conducted in Colombia around the potential neurological complications of Zika virus disease.
She discusses the possible link between Zika infection and Guillain-Barré, noting some of the difficulties and limitations of current testing methods and why it is so important to learn more about the effects of the virus on people.
Please note that this video is in Spanish. Subtitles can be found by clicking the third-from-right button in the player window.
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