MidnightWatcher – Prophecy in Motion

By Amy Maxmen – “This year is on track to be the worst on record for West Nile virus in the United States. As of 11 September, more than 2,600 new cases, including 118 deaths, had been reported from across the country to the US Centers for Disease Control and Prevention (CDC) in Atlanta, Georgia.

Symptoms of the mosquito-borne disease range from none (in most people) to life-threatening brain inflammation, and it can leave survivors with long-term disabilities including paralysis and fatigue. Researchers are now investigating suggestions that even mild infections may leave another lasting burden — kidney disease.

‘We are early in our understanding, but this really worries me,’ says Kristy Murray, an epidemiologist and clinical researcher at Baylor College of Medicine in Houston, Texas, who has found hints that the virus may persist in the kidney long after the initial infection. This week she is moving her work on the long-term consequences of West Nile to a new biosecurity-level-3 laboratory at nearby Texas Children’s Hospital, where she will explore a link between the virus and kidney disease.

Researchers agree that the claim needs to be investigated. ‘If Murray’s findings are true, we have to think about what to do with all of these people with mild infections,’ says William Reisen, an entomologist at the Center for Vectorborne Diseases at the University of California, Davis. But Murray is also facing scepticism, which she hopes to address in the latest phase of her research.

Murray’s quest began at a meeting of West Nile survivors in Texas in 2009, where a man in his early fifties who had recovered from a 2003 infection announced that he had kidney disease. He was dead within a year. To Murray, his illness brought to mind studies in which researchers had detected and cultured the virus in kidney tissue from laboratory animals long after they were infected with West Nile.

Murray collected urine samples from 25 survivors of West Nile and found that five had viral RNA in their urine well after they had been infected1, suggesting that the virus might have established itself in their kidneys. To examine whether the virus might harm kidneys over time, Murray’s team then looked for indicators of long-term kidney disease, such as excess protein in the urine, in samples from 139 people, most of whom were infected with the 2003 strain of the virus. She reported2 in July that 40% of that group showed signs of long-term kidney disease.” Read more.