COVID-19: Clinical Terms You Should Know

Pamela Cruz. Peninsula 360 Press [P360P].

Almost nine months after the declaration of the pandemic by COVID-19, the number of infections and deaths is increasing, as well as the doubts in clinical terms, since it is often complicated to understand the documents that come out every day regarding the virus.

Below you will find a series of words that will help you better understand the terminology that is so necessary today - and because of the pandemic. 

• Efficiency and Effectiveness

Both terms are often used interchangeably in the context of drugs or, now, in the performance of COVID-19 vaccines, especially in clinical trials, but there are key differences in both words.

According to the U.S. National Institutes of Health (NIH), efficacy refers to the performance under ideal circumstances, in this case, of a vaccine in clinical trials.

Instead, effectiveness refers more broadly to how the vaccine meets standards for success in the "real world" after it has been released for consumer use; this provides a more realistic picture of a vaccine.

• Quarantine and Isolation

The two words have been used very often over the past nine months, especially for actions to be taken when there has been exposure to COVID-19, however, they do not mean the same thing.

The quarantine does not specifically refer to 40 days, but to separation and restriction of movement for people who were exposed to a disease, in order to see if they get sick. 

The U.S. Department of Health and Human Services (HHS) states that in the case of COVID-19, it is for those who have come in contact with a known case of the virus, but are not yet showing symptoms, so that person will remain at home and away from others for 14 days after a risky exposure.

Isolation separates sick people with a contagious disease from those who are not sick. 

In this way, isolation usually means that the individual has been diagnosed with COVID-19 and is kept away from others - isolated - so as not to infect them, and is usually done inside the home, away from other members of the household.

Note that if several people in a household have confirmed VIDOC-19, it is okay to isolate them together, while if only one member tests positive, that person should be isolated from the others in the household and all members should be quarantined for 14 days.

• Asymptomatic vs. Pre-symptomatic

VOCID-19 disease can range from mild to very severe symptoms requiring hospitalization, however there is a big difference between someone who has an asymptomatic case and someone who is pre-symptomatic.

Asymptomatic people test positive for 19-COVID, but "no symptoms indicating a SARS-CoV-2 infection," but some people may develop symptoms days after a positive test.

These individuals would be classified as pre-symptomatic at the time of their positive test and will eventually develop symptoms, according to the NIH.

• Epidemic vs. Pandemic

The difference between an epidemic and a pandemic is the degree to which, according to the Center for Disease Control and Prevention (CDC), an epidemic occurs when there is a rise in cases of illness above normal in a limited population or area - for example, a single country - whereas an epidemic can become a pandemic if it spreads to several different countries or continents.

• Outbreak vs. Cluster

The CDC also explains that epidemic and outbreak are two terms that can actually be used interchangeably for the most part, although an outbreak is generally used to define a smaller specific geographic area. 

Clustering, on the other hand, often refers to outbreaks on small, specific scales, over a period of time, within a defined location.

• Community Propagation vs. Transmission

Transmission is technically used to describe how SARS-CoV-2 virus spreads from person to person; however, community spread is a term used to describe what happens when the disease spreads significantly in a given population without a clear source, refers the CDC.

• Mortality Rate vs.

These terms are often among the most confusing, but there are important differences in both. The mortality rate is calculated by reference to the total population, while the fatality rate only takes into account people affected by a given disease.

Thus, in the case of COVID-19, the case fatality rate -CFR-, is the specific number of people with confirmed diagnosis of COVID-19 who die as a result of the disease. An example of this is: out of every thousand people diagnosed with COVID-19, one person dies.

On the other hand, the mortality rate is a more general approximation of the number of deaths that occur within a larger or certain population, such as that of an entire country, said the World Health Organization -WHO-.

An example would be: Out of a population of 100,000 people, two die from COVID-19.

• ICU and hospitalization rate - intensive care unit - vs. capacity

Hospitalization and intensive care unit (ICU) rates refer to the number of people in a specific area who are hospitalized after a diagnosis of COVID-19, and are compared to the total population of a given area, such as a county, state, or country. 

The capacity of hospitals and ICUs, on the other hand, are statistics that describe the burden by COVID-19. The figures are generally expressed as a percentage: the number of occupied beds divided by the total number of beds.

In this case, it is necessary to point out that hospital capacity is not only a question of beds, but also of the personnel available to attend to patients, the CDC points out.

• Ventilator and Respirator

Although in Spanish-speaking countries both words refer to the same thing, according to the NIH and the CDC these two devices are not the same, since a ventilator, also known as a mechanical ventilator, is a machine that is generally used in a hospital and that blows air through tubes into the patient's airway.

While a respirator, it is a piece of personal protective equipment, which is worn over the mouth, nose or face to prevent the inhalation of airborne particles, gases or vapors, other than a mask.

In this regard, the CDC notes that N95 respirators are recommended for health care personnel in clinical settings, but not for the average person due to severe shortages of such equipment.

• Positivity Rate vs. Prevalence

According to the Johns Hopkins Bloomberg School of Public Health, the positivity rate, also known as the "percentage positive rate" or "percent positive", is that of all coronavirus tests performed that are actually positive. 

This is an indicator of whether enough testing is being done and whether enough asymptomatic and mild cases are being evaluated, the university notes.

Prevalence, on the other hand, he said, is a specific number of people who have -- or had -- COVID-19 during a specific time period, which reflects the number of truly positive individuals in the entire population, not just those tested. 

In that regard, he noted that prevalence can help researchers and decision-makers understand the broader picture of the spread of such a virus in a specific area or population.