The Brazilian Covid variant detected in the UK is running rife in the Amazon city where it first emerged, despite the population approaching herd immunity - suggesting the new strain can evade existing antibodies.
Scientists believe that around 75 per cent of Manaus' population was infected by the virus during Brazil's disastrous first wave last year, which should have given it one of the highest levels of immunity in the world.
But despite this, Manaus has suffered a resurgence in infections blamed on the P1 variant - with hospitals running out of oxygen last month and record numbers of burials taking place in the city.