A brief glossary of COVID-19 words and jargon

The COVID-19 coronavirus pandemic has introduced a whole host of new words, phrases and concepts into our daily vocabulary. Most of us know what most of them mean, but just for interest here is as quick glossary of some of those new phrases and jargon:

• COVID-19 - this is the name of the infectious disease that infected people suffer from, not the name of the virus itself. It is short for coronavirus disease 2019. 
• SARS-CoV-2 - this is the (rarely-used) name of the actual virus that spreads COVID-19. It is an acronyms for severe acute respiratory sydrome coronavirus 2. Why the COVID-19 disease is not therefore called SARS2 is a bit of a mystery to me - the 2003 SARS epidemic (which was spread by the SARS-CoV virus) was just called SARS, after all - but that's just how it happened. In the early phases of the epidemic (and even now), it was often referred to as simply "novel coronavirus", and often used interchangeably with COVID-19.
• Coronavirus - this is the general name for a family of viruses that cause diseases in mammals and birds, usually manifesting as respiratory tract disease in humans. This includes SARS, MERS and COVID-19, but also some cases of rhe common cold, pneumonia, bronchitis, etc.
• Pandemic - an extensive infectious disease epidemic that affects many large regions, or even the entire world. This includes the Black Death plague of the 14th Century, smallpox, tuberculosis, various cholera outbreaks, the 1918 Spanish flu, HIV/AIDS, and more recently the 2009 H1N1 swine flu outbreak and now COVID-19. (Here's an interesting graphic of how the main historical pandemics stack up). SARS and MERS did not quite make the World Health Organization definition for a pandemic, and neither did Ebola or Zika, but COVID-19 just did.
• Self-isolation - deliberate vountary separation of a person from the general public, as a means of preventing, or at least slowing, the spread of a virus. This typically involves staying home as much as possible, only venturing out for emergencies, having groceries delivered, and avoiding gatherings of large numbers of people. Also known as self-quarantine. Preventive self-separation is yet another term, used mainly for people at high risk (the elderly, immuno-compromized, etc).
• Social distancing - a conscious effort to reduce close contact between people in order to reduce community transmission of a disease. This can include any number of different activities, from literally leaving more space between people  (2 metres is the usual distance considered "safe", the maximum distance that droplets from a cough or sneeze typically travel) to not kissing or shaking hands to not going out at all. Now often referred to as "physical distancing" because some literalists objected to the suggestion that all social interaction should stop.
• Shelter in place order - a more stringent measure available to authorities, to compel citizens to stay in their home as and limit movement to essential trips. This would normally mean that all "non-essential" businesses are closed so that employees do not have to leave their homes, although the definition of "non-essential" may vary from place to place and situation to situation. This is a term mainly used in the USA.
• Lockdown - see shelter in place order above.
• Quarantine-shaming - public criticism (such as on social media) of people who, deliberately or through ignorance, flout the rules on social distancing. The popular Twitter hashtag #COVIDIOTS is just one example.
• Flattening the curve - slowing down community transmission of a disease (largely by social distancing and self-isolation, as described above), thereby preventing the rate of new cases, especially serious ones, from overwhelming the emergency medical services. "Planking the curve" is a variant: REALLY flattening the curve. The idea is not to let the number of serious cases spike so fast that it exceeds the capacity of a country's or region's health care system.
  
• An abundance of caution - a commonly-used phrase indicating a carefulness over and above the normal, but justified under the circumstances. It carries a slightly apologetic air, but the suggestion that such apparently excessive prudence is nevertheless necessary.
• R0 - the reproduction number or reproductive ratio or rate of an infection is the expected number of cases generated by each new case, essentially the rate at which an infection spreads. It's a measure of how communicable and virulent the infection is. The R0 for COVID-19 is estimated at anywhere between 1.4 and 3.9, about the same as SARS, more than MERS and H1N1, but significantly less than measles, smallpox, mumps, etc.
• Herd immunity - the idea that, when enough people become infected with a disease (often estimated to be around 60% of the population) and either die or become immune, then the disease will fizzle out on its own.
• Behavioural fatigue - a less commonly-used term, but one currently coming under heated discussion in Britain among other places, this is the (unproven) idea that people will eventially get tired of restrictive measures like social distancing, and rebel against them, or at least will not be able to maintain the new patterns of vigilant behaviour for very long.
• Personal protective equipment (PPE) - accoutrements needed by front-line healthcare workers (NOT everyone else), including rubber gloves, face masks, face shields, respirator masks, gowns, shoe covers, etc.
• YOLO (You Only Live Once) - not specifically COVID-19 related but often-mentioned of late, this refers to a carpe diem, live life to the fullest attitude, often exhibited by younger people, and often entailing a degree of risk or wilful ignorance, particularly in times like these when community conformity is at a premium.
• Fomite - a term occasionally encountered in some more technical articles, fomite just means any inanimate object that can be used to transfer a viral infection, i.e. anything from doorknobs, kitchen surfaces, faucets, snd light switches to medical equipment and, of course, human skin and clothing.
• Furlough - originally a military term, this has come to be used for any temporary lay-off from work, with the right to be reinstated at some future time. Furloughed workers are not paid, but they do typically retain employment benefits like health insurance.
• Contact tracing - a process used to identify and monitor individuals who have had close contact with someone who is infected with the virus, with the goal of reducing infection transfer within the population. This may be done automatically by a phone app, or manually by trained staff.
• Double the bubble - a controlled relaxation of quarantine measures whereby a family can choose to socialize at close quarters with one other family (but no-one else).