Healthcare Terms In A Covid-19 World

Although this phrase isn’t unique to COVID-19, it’s at the heart of the efforts to stop the virus’ spread. The UK’s Royal College of Nursing tells us that the chain of infection is the series of events necessary so that germs (bacteria, fungi and viruses) can infect a person. When we can stop one event, we can stop the spread of infection¹. The links in the chain of infection are these:

The infectious agent: the germ that causes the infection.

The reservoir: the place where germs can live and multiply. The reservoir can be a person or anything in that person’s surroundings—furniture, healthcare equipment, and so on.

The portal of exit from the reservoir: the means by which the germ can escape from the reservoir. This includes blood, saliva, stool, vomit, the air that an infected person breathes, coughs or sneezes, and the transfer of germs between surfaces—say, from the top of a bathroom vanity to a person’s hands.

The mode of transmission: the means by which germs move, or spread, from one place to another.

The portal of entry into the "host": the germs that have been moved from the reservoir now invade another person (the "host"). They can enter by being swallowed or inhaled, or through wounds, cuts and injection sites.

The susceptible host: a person who is vulnerable to developing infection. This includes children, senior citizens, those who are ill, malnourished, dehydrated or on medications that can lower immunity.¹

These are steps toward stopping the chain of infection.

In case investigation, public health staff work with patients—ones who have suspected or confirmed infection—to help them recall everyone with whom they have had close contact during the time in which they may have been infectious.²

The health officials begin contact tracing by warning these exposed individuals (contacts) of their potential exposure as rapidly and sensitively as possible. Contacts are told that they may have been exposed to a patient with the infection, but not the identity of that patient. They receive education, information and support to understand their risk, their risk of exposing others even if they do not feel ill themselves, and ways to separate themselves from others who are not exposed and monitor themselves for illness.²

In her spring 2020 webinar, Kent State epidemiologist Tara Smith discussed the transmission risks inherent in life on college campuses. Related news has carried distressing reports of the virus’ rapid spread in senior living and care facilities. The latter locations are known as congregate housing: "a shared living arrangement that combines housing and services for older adults and people with disabilities."³ The Centers for Disease Control and Prevention (CDC) places a priority on case investigation and contact tracing in "care facilities, other congregate living settings and households with many people living in one house."⁴

Currently, two types of tests for COVID-19 are available.

Viral tests are used to determine whether patients have the virus now. They check samples from the patient’s respiratory system, perhaps using swabs of the inside of the nose. Some tests are point-of-care tests, and their results may be available at the testing site in less than an hour. Other tests must be sent to a laboratory to analyze, which takes 1-2 days once the lab receives the sample.⁵

Antibody tests are used to determine if patients have had the virus in the past. They check blood in the search for antibodies (disease-specific proteins that help fight infection and often build immunity to it). Depending on timing of infection and of the test, the test may not find antibodies in someone with a current COVID-19 infection. Antibody tests should not be used to diagnose COVID-19.⁶

The million-dollar question seems to be when a COVID-19 vaccine will be available. According to the Mayo Clinic, "A vaccine to prevent coronavirus disease 2019 (COVID-19) is perhaps the best hope for ending the pandemic. Currently, there is no vaccine to prevent COVID-19, but researchers are racing to create one."⁷

The race is on, but the process is time-consuming. The CDC lists six stages⁸ of vaccine development:

• Exploratory stage
• Pre-clinical stage
• Clinical development
• Regulatory review and approval
• Manufacturing
• Quality control

Clinical development alone is a multiphase process.

• "During Phase I, small groups of people receive the trial vaccine
• In Phase II, the clinical study is expanded and the vaccine is given to people who have characteristics (such as age and physical health) similar to those for whom the new vaccine is intended
• In Phase III, the vaccine is given to thousands of people and tested for efficacy and safety
• Many vaccines undergo Phase IV formal, ongoing studies after the vaccine is approved and licensed"⁹

Clearly, the needs surrounding the pandemic continue. This is a time for knowledgeable, decisive public health leaders in local, national and international communities. If you want to effect change at the highest level and lead new conversations about solving urgent challenges, consider the CEPH-accredited online Master of Public Health program.