In early 2020 the world awoke to a rapidly unfolding health crisis more severe than anything seen since the devastating Spanish influenza pandemic of 1918/1919 which claimed some 50 million lives. Despite vastly more sophisticated health systems, the Covid pandemic was still able to overwhelm first-world health systems and claim at least seven million deaths. It almost brought many of the world's economies to their knees. The medical-scientific community, no less than the general public, were stunned by this unanticipated pandemic caused by a virus completely new to humankind. Many questions still remain to be answered, not least the still unsolved question of whether the virus arose naturally following spillover from the animal world – in other words, a zoonotic disease – or whether it was a leak from a laboratory housing or experimenting with the virus. These are intensely important issues and they require urgent answers if we are to anticipate and adequately prepare for future similar new infections of humankind. New infectious diseases will undoubtedly appear in the future as humans maintain their contact with exotic animals and their ecosystems or continue to be less meticulous with laboratory safety.

From biblical times to the present, plagues, epidemics and pandemics have played a major role in influencing the course of human history. And yet, if medical science has largely controlled, eliminated and even eradicated many of these diseases, why are we facing more and more previously unheard-of new infectious diseases? Are they genuinely ‘new’, or are we just getting better at picking more of them up with our far more advanced scientifically sophisticated tools?

Public health institutions such as the NICD are equipped with increasingly sophisticated, powerful and technologically advanced tools to detect pathogenic organisms. Diagnoses are without doubt much more precise, rapid and accurate than even a decade ago. Advanced technology strikingly demonstrated its prowess in January 2020 by discovering the causative agent of the new disease of Covid, the novel coronavirus, SARS-CoV-2, within a week of recognising the clinical illness. It soon also established that SARS-CoV-2 was a genuinely new infection of humans and, as is the case with the great majority of truly new communicable diseases, originated from animal sources (zoonotic diseases).