Question

could you please help me with this question;

How has the Zika outbreak in Brazil and in the USA, created clinical study trials and/or community trials? What type of research studies are occurring due to the Zika outbreak?

Answer 1

Zika is a mosquito-borne virus which out broke in 2016 majorly in South America and other tropical countries of Africa. Zika virus is not a new virus it was found long back in 1947 by scientists in the Zika forest in Uganda. There were only a few cases reported before 2013. It has become more prevalent after the multiple outbreaks in Pacific islands and south-east Asia which then spreads to Brazil estimated around 1.5 million infected people. As the large outbreak also resulted in many birth defects called microcephaly, an abnormality in babies forming small heads. After this large outbreak in Brazil it led scientist to link the virus to microcephaly. Cases of the virus in the United States dropped from 5,102 in 2016 to 385 this past year and in the year 2019 no case was observed until.

Transmission: It is spread by mosquitoes and so is called an “arbovirus” it can be transmitted by an Aedes mosquito after it bites an infected person and then bites another host, It can be transmitted from infected mother to her child, it can be also spread through sexual contact or blood transfusion. Aedes aegypti and Aedes albopictus species are the two most common mosquitoes to transmit the virus. Aedes mosquitoes usually bite during the day, mostly during early morning and evening. This is the same mosquito that transmits dengue, chikungunya and yellow fever.

Research on zika virus: One of the most intriguing question into Zika Virus research is that " Why a virus that was discovered and that existed for decades in a much less harmless state became more destructive and associated with Guillain-Barre syndrome in adults and microcephaly in newborn babies, reaching epidemic levels in Latin America and French Polynesia.Few of the recent reports have emphasized that a single gene mutation led to an otherwise harmless strain into a lethal devastating epidemic force.

Few groups, Xu and coworkers and Yuan et al have recently reported their findings that S139N mutation which affected a viral protein involved in making of viral protective coat and viral assembly was observed to have caused more deaths in experimental mice and severe damage to cultured human cells important to early brain development. Though these findings are yet to be extrapolated to primates for a better understanding of virus function in nature.

Another group of researchers Pei-Yong Shi and coworkers have uncovered another plausible explanation reporting their findings in Nature, that a new mutation makes it easier for viruses to infect their vector- Aedes aegypti. The team observed that the more recent viruses released much higher levels of a protein known as NS1, which has been shown to help other related viruses overcome mosquito immune defenses. The mutation in chain of amino acids that make up the protein NS1 accounts for the enhanced epidemic ability and pathogenecity of the virus. Though, the group believes that there could be more than one change in viral genome of Zika that has made it explosively epidemic.

Therefore, investigations and experiments are going on to decode the change that has enhanced the Zika potential based on single gene mutation concept, yet a lot many theories with different concepts might come up that would enable us to understand how mutations change the viral protein function and what impact it confers to the pathogenecity of virus.