Researchers at the University of California, Los Angeles (UCLA) have developed a safe and highly effective Zika vaccine technology in preclinical mouse models. In a pregnant mouse model, the vaccine prevented both the pregnant mother and the developing fetus from developing systemic infections. The study was published in Microbiology Spectrum, a journal of the American Society for Microbiology.
Immunized mice showed high levels of cell-mediated immune responses, in the form of increased numbers of effector T cells, compared with unvaccinated mice. The researchers have also tested the vaccine in several other mouse models, in which the vaccine is found to be safe and potentially protective.
The impetus for this work was the Zika virus outbreak in 2016, which spread rapidly throughout the Americas and affected millions of people, causing severe socioeconomic hardship. Zika is the first mosquito-borne virus capable of affecting human reproduction.
To date, there is no approved vaccine or other treatment for the Zika virus. Investigations into other ways to fight the virus have also failed to lead to clearly effective countermeasures. “But because RNA viruses – the category to which both Zika and the SARS virus family belong – are very likely to evolve and mutate rapidly, there will be more outbreaks in the near future,” Arumugaswami said.
Worse yet, climate change is expanding the allowable habitat of mosquitoes like Aedes aegypti, which transmits the Zika virus to humans, putting populations at risk.
The average interval between phases of widespread Zika virus transmission is about 7 years. “It’s only a matter of time before we start seeing the virus spread again,” said Kouki Morizono, M.D., Ph.D., associate professor of medicine at UCLA and co-lead author of the study.
Arumugaswami said: “The ongoing COVID-19 pandemic has shown us the power of a strong pandemic preparedness plan and clear communication on prevention methods – all of which have been achieved. culminating in the rapid deployment of safe and reliable vaccines.”
Therefore, it is essential to develop a robust pandemic preparedness plan. “Our study is an important first step in developing an effective vaccination program that can limit the spread of Zika virus and prevent large-scale transmission,” said Arumugaswami.