Glossary

Adjuvant	An adjuvant is a pharmacological or immunological agent that improves the immune response of a vaccine. Adjuvants may be added to a vaccine to boost the immune response to produce more antibodies and longer-lasting immunity, thus minimizing the dose of antigen needed
Aerosol Generating Procedures	An aerosol generating procedure is a medical procedure that creates aerosols in addition to those that the patient creates regularly from breathing, coughing, sneezing, and talking.
Aerosols	Suspensions of solid or liquid particles in air or gas small enough to remain airborne for prolonged periods due to low settling velocity. Aerosols are measured by effective diameter (area-weighted mean radius). Particles with an effective diameter smaller than 10 μm can enter bronchi, while those 2.5 μm or less can enter the gas exchange region in the lungs. Smaller effective diameters are associated with longer settling times. Coughing or sneezing generates many particles smaller than 10 μm. These particles rapidly shrink by evaporation, increasing the number (known as “droplet nuclei”) that behave as aerosols. Aerosols can remain airborne and be carried across large distances, which may result in long-range infections. This occurrence is affected by: dilution, infectious dose, the number of infectious particles, duration of shedding of infectious agent, and persistence of agent in the environment. Humans acutely infected with viruses tend to have higher virus titer (concentration) in their respiratory secretions, aerosolized when they sneeze or cough. Laboratories study persistence of infectivity of a virus in an aerosol through suspensions in fixed humidity to understand the rate of decay.
Airborne Virus	This refers to situations where droplet nuclei (residue from evaporated droplets) or dust particles containing viral organisms can remain suspended in the air for long periods of time. These organisms must be capable of surviving for long periods of time outside the body and must be resistant to drying.
Antibodies	Antibodies are Y-shaped proteins produced as part of the body’s immune response to infection. When the body encounters a microbe for the first time, B-Cells produce antibodies that specifically recognize the proteins associated with that particular microbe. The antibodies then work by recognizing and sticking to those specific proteins, and destroying them.
Antigens	A virus, toxin or other foreign substance which induces an immune response in the body, especially the production of antibodies.
B-Cells	B-Cells are a type of white blood cell that produce antibodies to attack specific microbial proteins. There are also Memory B-Cells which lay dormant in the body until activated by infection. They serve to remember how to make the needed specific antibodies.
Bradykinin	Bradykinin is a peptide that promotes inflammation. It causes blood vessels to expand and leak, and veins to shrink, which may lead to fluid build up as well as the lowering of blood pressure.
Bradykinin Storm	When the natural degradation of bradykinin is prevented and bradykinin builds up in an uncontrolled manner within the body, leading to harmful symptoms including inflammation, dry coughs, low blood pressure, and heart failure (to name a few).
Case Fatality Rate	Case fatality rate is calculated by dividing the number of deaths from a specified disease over a defined period of time by the number of individuals diagnosed with the disease during that time; the resulting ratio is then multiplied by 100 to yield a percentage. Not to be confused with a mortality rate. As an example, consider two populations. One population consists of 1,000 people; 300 of these people have the specified disease, 100 of whom die from the disease. In this case, the mortality rate for the disease is 100 ÷ 1,000 = 0.1, or 10 percent. The case fatality rate is 100 ÷ 300 = 0.33, or 33 percent. The second population also has 1,000 people; 50 people have the disease and 40 die from it. Here the mortality rate is 40 ÷ 1,000 = 0.04, or 4 percent; the case fatality rate, however, is 40 ÷ 50 = 0.8, or 80 percent. The incidence of death from the disease is higher in the first population, but the severity of disease is greater in the second.
Cellular Immunity	Cellular immunity is an immune response that does not involve antibodies. Usually it involves the activation of antigen-specific T-Cells.
Community Transmission	Infections identified in a given geographic area without a history of travel elsewhere and no connection to a known case. This is the most dangerous kind of transmission as it is impossible to trace possible exposures.
Confirmed Positive vs. Presumptive Positive	A presumptive case means that a local health agency has received a positive test result from a patient. But the test often needs to be validated with a second test. Some provincial labs, such as those in Ontario, British Columbia, Quebec and Alberta, conduct the second test locally, whereas other provinces need to send a sample to the National Microbiology Lab in Winnipeg.
Cytokine Storm	When an immune system causes an uncontrolled and excessive release of pro-inflammatory signalling molecules called cytokines. Normally, cytokines are part of the body’s immune response to infection, but their sudden release in large quantities can cause multisystem organ failure and death.
Droplet Transmission	Droplet transmission occurs when a person is in close contact with someone who is actively shedding the SARS-CoV-2 virus, and their respiratory droplets spread from their nose or mouth to the person’s mouth, nose, or eyes in sufficient volume for them to also become infected.
Elective surgeries	Surgery that is scheduled in advance, that does not involve an emergency.
Epidemic	An outbreak of a disease that spreads quickly and affects many individuals at the same time within a single region.
Epidemic Curve	An epidemic curve is a statistical chart used in epidemiology to visualize the onset of a disease outbreak. It will generally show the frequency of new cases compared to the date of disease onset. Studying the epidemic curve can help with the identification of the mode of transmission of the disease, as well as the incubation period and reproduction number.
Epidemiology	The branch of medical science that deals with the incidence, distribution, and control of disease in a population
Essential Services	Businesses and services that are considered by the regional or federal government to be required for maintaining basic societal function. An official list of BC Essential Services can be found here.
Exposure Event	Exposure events are when one or more COVID-19 positive people are present at a location where they may have come into close contact with others. Exposure events may or may not lead to outbreaks.
Flattening the Curve	Flattening the curve is a public health strategy to slow down the spread of COVID-19. The curve being flattened is the epidemic curve and refers to slowing down the infection rate so that hospitals will not become overwhelmed beyond capacity.
Fomite	Fomites are any inanimate object that, when contaminated with or exposed to infectious agents, can transfer the disease to a new host.
Herd Immunity	Herd immunity is a form of indirect protection from infectious disease that occurs when a sufficient percentage of a population has become immune to an infection, whether through vaccination or previous infections, thereby reducing the likelihood of infection for individuals who lack immunity.
Hydroxychloroquine	Hydroxychloroquine is an existing drug that was studied for potential positive effects against COVID-19 but eventually was determined to offer no benefit against the virus.
Immunity	The ability of an organism to resist a particular infection or toxin by the action of specific antibodies or sensitized white blood cells.
Immunocompromised	Having your immune system impaired or weakened as by drugs or illness. See Immunosuppression.
Immunosuppression	Suppression of the immune system and its ability to fight infection. Immunosuppression may result from certain diseases, or from certain drugs, such as some of those used to treat cancer. Immunosuppression may also be deliberately induced with drugs, as in preparation for bone marrow or other organ transplantation.
Incubation Period	The incubation period is the time elapsed between the exposure of a person to a pathogenic organism; and when that person becomes infectious or shows symptoms themselves.
Isolation	Isolation means staying at home and avoiding contact with other people on the chance that you might be contagious. Usually recommended if you have been in close contact with someone actively waiting on their COVID-19 test results.
Lockdown	A lockdown is when people are not allowed to enter or leave buildings or areas (including their homes) freely because of an emergency.
Mortality Rate	Mortality rate is calculated by dividing the number of deaths by the population at risk during a certain time frame and then multiplying that number by 100 to find the percentage. This method estimates the risk of dying of a certain disease, but for a true rate can only be calculated after the risk of death has concluded. As an example, consider two populations. One population consists of 1,000 people; 300 of these people have the specified disease, 100 of whom die from the disease. In this case, the mortality rate for the disease is 100 ÷ 1,000 = 0.1, or 10 percent. The case fatality rate is 100 ÷ 300 = 0.33, or 33 percent. The second population also has 1,000 people; 50 people have the disease and 40 die from it. Here the mortality rate is 40 ÷ 1,000 = 0.04, or 4 percent; the case fatality rate, however, is 40 ÷ 50 = 0.8, or 80 percent. The incidence of death from the disease is higher in the first population, but the severity of disease is greater in the second.
N95 Respirator	An N95 mask or N95 respirator is a particulate-filtering device worn on your face that meets the N95 classification of air filtration, meaning that it filters at least 95% of airborne particles. N95 masks do not protect against gases or vapours. They are considered functionally equivalent to other international certified masks, such as FFP2 respirators of the European Union and KN95 respirators of China, although performance may vary.
Nasopharyngeal Swab	A nasopharyngeal swab is a method for collecting a clinical test sample of nasal secretions from the back of the nose and throat. The sample is then analyzed for the presence of organisms or other clinical markers for disease
Negative-Pressure Rooms	Negative room pressure is an isolation technique used in hospitals and medical centers to prevent cross-contamination from room to room. The pressure is kept artificially low so that when the door to enter is opened, potentially harmful air does not leak from one room to another.
Non-Essential Services	These are businesses and services that are not considered by the regional or federal governments to be required to maintain basic societal functions.
Novel Coronavirus	A novel coronavirus is a new coronavirus that has not been previously identified.
Oropharyngeal Swabs	An oropharyngeal swab is a method for collecting a clinical test sample of nasal secretions from the back of the throat in the tonsillar region. The sample is then analyzed for the presence of organisms or other clinical markers for disease
Outbreak	An outbreak is a sudden increase in occurrences of a disease in a particular time and place. It may affect a small and localized group or impact upon thousands of people across an entire continent.
Outbreak Event	An outbreak event is declared when an exposure event leads to multiple transmissions. An outbreak event will not be declared over until 2 incubation periods have gone by with 0 new related cases.
Pandemic	An outbreak of a disease that spreads quickly and affects many individuals at the same time within many countries or the world.
PCR	PCR stands for Polymerase chain reaction. It is the main method used to test for COVID-19. A DNA sample is taken from a patient, and then millions to billions of copies of the sample are rapidly made, allowing scientists to determine if the sample contains COVID-19 DNA.
PHAC	PHAC stands for the Public Health Agency of Canada.
Physical Distancing	Physical distancing (previously referred to as social distancing) is a set of measures used to minimize close contact with others in the community. These measures include: Avoiding crowded areas and non-essential travel, keeping 2 metres apart from those outside your household bubble, avoiding greetings like handshakes or high-fives, and encouraging persons considered at high risk to stay home unless necessary.
PPE	PPE stands for Personal Protective Equipment. Such items can include masks, gloves, medical gowns, and other specialized items.
Pre-Symptomatic	The period of time after infection, but before any symptoms begin to show. A person may be pre-symptomatic with COVID-19 but still shed the virus contagiously.
Protease inhibitor	Protease inhibitors are a class of antiviral drugs that are widely used to prevent viral replication by selectively binding to viral proteases and blocking proteolytic cleavage of protein precursors that are necessary for the production of infectious viral particles.
Quarantine	Quarantine means you have been directed by Public Health to stay at home and avoid contact with others for a given amount of time. It usually happens if you test positive for COVID-19, or develop symptoms associated with COVID-19.
R-naught or R0	Pronounced R nought or R zero, it is the basic reproduction number of a disease. The value can be thought of as the expected number of cases directly generated by one case in a population where all individuals are susceptible to infection. This number is not a biological constant for a pathogen as it is also affected by other factors such as environmental conditions and the behaviour of the infected population.
Remdesivir	Remdesivir is an antiviral drug commonly connected with treatment of Ebola, which is now being studied for use against COVID-19.
Resolved Case	In order for a COVID-19 case to be considered “resolved” in BC, the patient is required to show no symptoms after 10 days of isolation.
Respirator	A mask or device worn over the mouth and nose to protect the respiratory system by filtering out dangerous substances (such as dust, fumes, or bacteria) from inhaled air.
SARS-CoV-2	SARS-CoV-2 is the name of the virus that causes the disease COVID-19.
Second Wave	A phenomenon of infections that can develop during a pandemic. The disease infects one group of people first. Infections appear to decrease. And then, infections increase in a different part of the population, resulting in a second wave of infections.
Self-Monitoring	The 14 day period after you have been exposed to COVID-19 where you must watch for signs of fever, cough, and/or difficulty breathing. You are encouraged to write down your temperature every day and to try not to use medicines that reduce fever.
Serological Test	Serological testing checks for an antibody response to the SARS-CoV-2 virus. This test is not able to determine if a person is actively infected or shedding the virus, only if they had previously been infected with it.
Serology	The scientific study or diagnostic examination of blood serum, especially with regard to the response of the immune system to pathogens or introduced substances.
Shelter in Place	An official order, issued during an emergency, that directs people to stay in the indoor place or building that they already occupy (usually their home) and not to leave unless absolutely necessary.
Social distancing	See Physical Distancing
Steroid Dexamethasone	Dexamethasone is a type of corticosteroid medication. It is used in the treatment of many conditions, including rheumatic problems, several skin diseases, severe allergies, and is currently being studied as a treatment for COVID-19.
Super-Spreader	An individual who is highly contagious and capable of transmitting a communicable disease to an unusually large number of uninfected individuals.
Super-Spreader Event	An event where the exposure to one or more infected individuals leads to the transmitting of a communicable disease to an unusually large number of uninfected individuals.
Symptomatic	Showing symptoms of disease.
T-Cells	T cell, also called T lymphocyte, type of leukocyte (white blood cell) that is an essential part of the immune system. T cells are one of two primary types of lymphocytes—B cells being the second type—that determine the specificity of immune response to antigens (foreign substances) in the body.
Transmission	Transmission is the passing of a pathogen causing communicable disease from an infected host to a particular individual or group.
Vaccine Candidate	Vaccine candidates are newly developed vaccines currently being studied to ensure safety and efficacy before they are approved to be brought to market for use.
Ventilator	A ventilator is a machine that provides mechanical ventilation by moving breathable air into and out of the lungs, to deliver breaths to a patient who is physically unable to breathe, or breathing insufficiently.
Viral Shedding	Viral shedding occurs when a virus has replicated inside your body and is released into the environment. At this point, the infected person may be contagious. Shedding of SARS-CoV-2 may happen regardless of outward symptoms.
WHO	Stands for the World Health Organization.
Zoonotic	Pertaining to a zoonosis: a disease that can be transmitted from animals to people or, more specifically, a disease that normally exists in animals but that can infect humans.