In early 2022, just about two decades just after Covid was declared a pandemic by the Globe Health Corporation, industry experts are mulling a significant query: when is a pandemic “over”?
So, what’s the answer? What standards ought to be used to identify the “end” of Covid’s pandemic stage? These are deceptively uncomplicated concerns and there are no simple responses.
I am a laptop or computer scientist who investigates the advancement of ontologies. In computing, ontologies are a signifies to formally composition understanding of a matter area, with its entities, relations, and constraints, so that a computer system can approach it in a variety of apps and help individuals to be more exact.
Ontologies can find out understanding that is been forgotten till now: in one particular occasion, an ontology recognized two supplemental practical domains in phosphatases (a team of enzymes) and a novel area architecture of a aspect of the enzyme. Ontologies also underlie Google’s Understanding Graph which is guiding all those knowledge panels on the correct-hand aspect of a look for final result.
Making use of ontologies to the queries I posed at the start out is helpful. This technique helps to clarify why it is complicated to specify a slice-off level at which a pandemic can be declared “over”. The procedure entails accumulating definitions and characterizations from domain specialists, like epidemiologists and infectious condition researchers, consulting appropriate research and other ontologies, and investigating the mother nature of what entity “X” is.
“X”, right here, would be the pandemic alone – not a mere shorthand definition, but on the lookout into the homes of that entity. These types of a specific characterization of the “X” will also reveal when an entity is “not an X”. For occasion, if X = property, a assets of properties is that they all have to have a roof if some item does not have a roof, it unquestionably isn’t a home.
With these traits in hand, a precise, formal specification can be formulated, aided by supplemental procedures and resources. From that, the what or when of “X” – the pandemic is more than or it is not – would logically stick to. If it does not, at least it will be doable to make clear why points are not that uncomplicated.
This sort of precision enhances wellness experts’ endeavours, helping people to be a lot more exact and talk more precisely. It forces us to make implicit assumptions express and clarifies exactly where disagreements could be.
Definitions and diagrams
I executed an ontological investigation of “pandemic”. Initially, I wanted to come across definitions of a pandemic.
Informally, an epidemic is an occurrence during which there are various scenarios of an infectious illness in organisms, for a limited duration of time, that influences a neighborhood of claimed organisms residing in some location. A pandemic, as a minimal, extends the area the place the infections take place.
Future, I drew from present foundational ontologies. This consists of generic types like “object”, “process”, and “quality”. I also made use of area ontologies, which comprise entities precise to a subject matter domain, like infectious health conditions. Amid other sources, I consulted the Infectious Ailment Ontology and the Descriptive Ontology for Linguistic and Cognitive Engineering.
(1) Is [pandemic] anything that is occurring or developing? Of course (perdurant, i.e., something that unfolds in time, rather than be wholly existing).
(2) Are you ready to be present or participate in [a pandemic]? Certainly (function).
(3) Is [a pandemic] atomic, i.e., has no subdivisions and has a definite endpoint? No (accomplishment).
The word “accomplishment” may well appear unusual right here. But, in this context, it would make very clear that a pandemic is a temporal entity with a minimal lifespan and will evolve – that is, stop to be a pandemic and evolve back to epidemic, as indicated in this diagram.
Following, I examined a pandemic’s properties described in the literature. A extensive checklist is described in a paper by US infectious illness specialists published in 2009 through the global H1N1 influenza virus outbreak. They collated eight properties of a pandemic.
I detailed them and assessed them from an ontological point of view:
- Wide geographic extension. This is an imprecise characteristic – be it fuzzy in the mathematical feeling or approximated by other signifies: there is not a crisp threshold when “wide” commences or finishes.
- Sickness movement: there is transmission from spot to put and that can be traced. A of course/no characteristic, but it could be produced categorical or with ranges of how bit by bit or rapid it moves.
- Superior attack rates and explosiveness, or: many people today are afflicted in a small time span. Many, shorter, rapid – all suggest imprecision.
- Minimal inhabitants immunity: immunity is relative. You have it to a degree to some or all of the variants of the infectious agent, and also for the populace. This is an inherently fuzzy attribute.
- Novelty: A of course/no characteristic, but one particular could incorporate “partial”.
- Infectiousness: it have to be infectious (excluding non-infectious issues, like being overweight), so a apparent yes/no.
- Contagiousness: this may perhaps be from man or woman to man or woman or as a result of some other medium. This property includes human-to-human, human-animal middleman (e.g., fleas, rats), and human-environment (notably: h2o, as with cholera), and their attendant aspects.
- Severity: Historically, the expression “pandemic” has been used additional generally for intense disorders or these with superior fatality charges (e.g., HIV/AIDS) than for milder kinds. This has some subjectivity, and so could be fuzzy.
Properties with imprecise boundaries annoy epidemiologists simply because they may perhaps lead to distinctive outcomes of their prediction products. But from my ontologist’s viewpoint, we’re acquiring somewhere with these houses. From the computational aspect, automatic reasoning with fuzzy attributes is doable.
COVID, at least early in 2020, simply ticked all 8 boxes. A suitably automated reasoner would have categorised that situation as a pandemic. But now, in early 2022? Severity (level 8) has mostly reduced and immunity (stage 4) has risen. Point 5 – are there worse variants of concern to come – is the million-dollar dilemma. A lot more ontological examination is desired.
Highlighting the troubles
Ontologically talking, then, a pandemic is an celebration (“accomplishment”) that unfolds in time. To be labeled as a pandemic, there are a amount of options that are not all crisp and for which the imprecise boundaries have not all been set. Conversely, it implies that classifying the function as “not a pandemic” is just as imprecise.
This is not a comprehensive reply as to what a pandemic is ontologically, but it does lose light on the difficulties of calling it “over” – and illustrates perfectly that there will be disagreement about it.