The Zika virus, which rose to epidemic proportions in 2015, can cause devastating congenital brain abnormalities and has been linked to Guillain-Barré syndrome, a condition in which the immune system attacks the nerves and can result in paralysis. It’s transmitted by everyone’s favorite insects, mosquitoes. (Actually, my favorite insects are dead ones.) According to the CDC, many people will have no symptoms or very mild symptoms, but for pregnant woman, the danger of passing the virus onto the fetus is high. This has had heartbreaking consequences. In a study discussed in the NY Times:

But 15 children, eight girls and seven boys, had a range of symptoms, most of which had not improved since infancy. All had severely impaired motor skills, with all but one child meeting the conditions for a diagnosis of cerebral palsy. Most had seizures and sleeping problems. Eight had been hospitalized at some point, most for bronchitis or pneumonia. Nine had difficulty eating or swallowing, which can be life-threatening because food can get stuck in the lungs or the children can be malnourished.

However, it seems the very thing that allows the Zika virus to cause such devastation in babies may be the key to a new brain cancer treatment. A new study, published in the Journal of Experimental Medicine, showed that injecting the Zika virus in mice “shrank aggressive tumors… yet left other brain cells unscathed.”

Human trials are still a way off, but experts believe Zika virus could potentially be injected into the brain at the same time as surgery to remove life-threatening tumours…

Researcher Dr Michael Diamond said: “Once we add a few more changes, I think it’s going to be impossible for the virus to overcome them and cause disease.

“It looks like there’s a silver lining to Zika. This virus that targets cells that are very important for brain growth in babies, we could use that now to target growing tumours.”