There may be a single mutation far from spreading the Zika virus around the world, new research has found. The infectious virus, which caused a global health emergency in 2016, required a change in its genetic code to create an infectious new variant that can cause the devastating birth defects that affected many babies during previous outbreaks. used to do.
The results of research in mice by researchers at the La Jolla Institute for Immunology in California were published in the journal Cell Reports.
The World Health Organization (WHO) also warned last week that the next pandemic could be triggered by insect-borne pathogens, including Zika and dengue.
Emerging viruses, especially those that pose a health risk to humans, are constantly monitored and used to identify potential threats and treatments. Experts working with coronaviruses have now proposed theoretical changes to the virus genome that could potentially change its transmissibility. Other viruses like Zika are no different.
Zika is mainly transmitted by mosquitoes and has relatively mild symptoms. However, pregnant women infected with the virus pass it on to their unborn babies, resulting in microcephaly that causes babies to have small heads and underdeveloped brains. The Zika epidemic that began in Brazil and affected the United States in 2015 and 2016, caused more than 3,500 cases of infantile microcephaly. The World Health Organization said it represents a significant, long-term problem.
The new study has identified a potential evolution of Zika that could enable it to increase transmission capacity even in countries that have been immune to previous outbreaks. The researchers used a mouse model and mosquitoes to simulate the transfer of the virus between vector and human hosts and discovered small genetic mutations that increased the virus’s infectious characteristics. This created a variant capable of evolving immunity conferred by previous infection with dengue or a similar pathogen, suggesting that the mutation would enable Zika to return to previously affected countries.
Study lead author Professor Suzanne Shresta said the Zika variant had evolved to the extent that the cross-protective immunity afforded by a previous dengue infection was no longer effective in mice.
If this version becomes prevalent, the same issues will have to be tackled in real life, the researcher said.
According to the WHO, dengue fever infects 390 million people annually in 130 countries where it is endemic, while Zika virus was detected in at least 89 countries during the 2016 outbreak.