The World Health Organization has highlighted the potential danger of a deadly, as-yet-unknown pathogen.
Each year, the global health body convenes a meeting of senior scientists in an effort to put together a concise list of the most likely diseases to cause a major international public health emergency.
While it isn't surprising to see viruses such as Zika and Ebola make it on to the list, this time around something unexpected has been added - a mysterious malady referred to only as 'Disease X'.
As it turns out however, this unspecified disease is actually a placeholder.
"Disease X represents the knowledge that a serious international epidemic could be caused by a pathogen currently unknown to cause human disease," WHO said in a statement.
With the potential for gene editing to produce a disease far deadlier than anything ever seen before, it is not difficult to see why health authorities are being advised to expect the unexpected.
"History tells us that it is likely the next big outbreak will be something we have not seen before," said John-Arne Rottingen, chief executive of the Research Council of Norway.
"It may seem strange to be adding an 'X' but the point is make sure we prepare and plan flexibly in terms of vaccines and diagnostic tests."
"As the ecosystem and human habitats change there is always the risk of disease jumping from animals to humans," Rottingen said.
"It's a natural process and it is vital that we are aware and prepare. It is probably the greatest risk."
"We want to see 'plug and play' platforms developed which will work for any, or a wide number of diseases; systems that will allow us to create countermeasures at speed."
While we can be thankful Disease X probably doesn't exist yet, the likelihood of it appearing in the future is definitely something we should be aware of, in the hopes we can stay one step ahead of any future threats – especially as we continue to encounter and take over what remains of the natural environment.