CP and influenza: CP therapy has been an immunization strategy since the 20th century in the emergency intervention of the Spanish flu (1917–1918), West Nile virus, 2009 influenza A (H1N1), avian influenza A (H5N1), SARS (2003), Argentine hemorrhagic fever (1960s) and the Ebola virus outbreak in the West Africa pandemics (2013–2015).