Dr Peter Hotez gestured at three tyres dumped on the weed-ravaged, litter-strewn roadside by a boarded-up house on Worms Street.
To Hotez they were more than an eyesore – they signified a potential health hazard, the perfect breeding ground for mosquitoes that could spread the Zika virus.
The World Health Organisation has warned that the virus is spreading “explosively” through the Americas, with one estimate that there could be as many as 4m infections across the continent over the next year.
At a special briefing in Geneva on Thursday, Margaret Chan, the WHO director general warned it was a threat of “alarming proportions”. Hotez, an eminent scientist and researcher who is dean of the National School of Tropical Medicine at Baylor College of Medicine, agrees.