ARE YOU UP TO SPEED WITH VIRUS JARGON?
CORONAVIRUS: A family of viruses named after the halo — or corona — of protein spikes that stud the outside of each virus particle. Four coronaviruses are behind about 20 per cent of cases of the common cold, while three — SARS (severe acute respiratory syndrome), MERS (Middle East respiratory syndrome) and Covid19 — can cause severe illness.
R0: Pronounced ‘R nought’, this figure represents how many people one sick person will, on average, infect. The higher the R0 value, the more challenging a disease is to control. Measles is highly infectious and has an R0 value of 12 to 18. The R0 value for Covid-19 is 2.5 to 4.
SUPER-SPREADER: This is someone who infects far more people than average. This might be because their job means they are in contact with more people than usual, or their bodies release unusually high amounts of a virus.
HERD IMMUNITY: When enough people become immune to an illness, either because they’ve already had it or they’ve been vaccinated against it, the disease struggles to spread. In other words, there are enough immune people in the ‘herd’ of a community to protect the few who aren’t. ASYMPTOMATIC: Someone who has an infection but doesn’t have symptoms. Such people can still spread coronavirus. SOCIAL DISTANCING: Reducing the contact you have with other people by working from home or shopping for food only when essential, to slow the spread of an infection. CLOSE CONTACTS: At the start of the pandemic, close contacts of coronavirus patients were
traced and given health advice or put into isolation to stop the virus spreading.
A close contact is someone who lives in the same household as the person with the virus, has had physical contact (such as shaking hands) with them or been within two metres of them for longer than 15 minutes. ANTIGEN: A substance that the immune system sees as foreign and produces cells called antibodies to fight it off. Various companies are developing antigen tests for Covid-19. A positive result means someone has the virus at the time of testing.
‘ Current NHS tests don’t look for an antigen but for traces of the virus’s genetic material,’ explains Dr Simon Clarke, a microbiologist at the University of Reading. ANTIBODY:
A protein made by the body’s immune system to destroy antigens such as Covid-19. An antibody test can tell you if you have had the virus.
PPE: Personal protective equipment covers clothing and equipment to keep people safe at work. PPE for coronavirus includes gloves, aprons, visors, goggles and face masks. FFP3 masks provide the highest protection, filtering out at least 95 per cent of airborne particles.
INCUBATION PERIOD: The time between catching an infection and symptoms starting. For coronavirus, this is usually five days but can be as long as a fortnight or as little as a day.
EPIDEMIOLOGY: The science of how a disease spreads. It is carried out by epidemiologists, who investigate where an outbreak started, who is at risk, how to control it and how to stop it happening again.