There is an overwhelming amount of information available on the disease that has created the pandemic, but much of it is social media malarkey. To help separate the fact from fiction, KTW editor Christopher Foulds contacted three Kamloops doctors, who agreed to take part in a multi-part Q&A series that began in the Jan. 6 print edition of Kamloops This Week and online. This is part 2 and the Q&A series will continue in subsequent print editions and online until the queries are exhausted. Dr. Elizabeth Parfitt is a physician specializing in treating and diagnosing patients with infections at Royal Inland Hospital. Dr. Annemie Raath is a hospitalist at RIH, a family physician skilled in caring for hospitalized patients and who has been working on the COVID unit throughout the pandemic. Dr. Carol Fenton is a Kamloops-based medical health officer for Interior Health, a position that is a public health and preventive medicine specialist. Neither of the doctors are vaccinologists, virologists or immunologists. The information in the Q&A reflects current understanding as of Dec. 30, 2020, and will likely change rapidly, as has most everything since the pandemic was declared on March 11, 2020.
Click here to read part 1 of the COVID-19 Q&A. Click here to read part 2 of the COVID-19 Q&A.
Q: We have been told pandemic-related measures — such as wearing masks, keeping our distances and washing our hands — must continue even after vaccination is done. Why?
DR. PARFITT: Rolling out the COVID vaccine is probably going to take the better part of a year to get it to everyone who wants it.
At first, we have to continue our other layers of defence, like distancing, masking and hand hygiene, until we start seeing drops in numbers or at least in hospitalizations and deaths as we immunize the highest-risk individuals and their caregivers and contacts. Our public health leaders will indicate how that process goes and we will learn from other countries, too. The other issue is we don’t know for sure, although we do expect, that the vaccine prevents transmission. We know a vaccinated person is much less likely to develop COVID-19, but we are not sure yet that they cannot somehow spread it to others. Again, with each passing week, we will know more. But for the next few weeks and likely months, getting vaccinated should not change our behaviours . We have to continue to fight the pandemic with all of the tools we have.
Q: We have an annual influenza vaccine that targets strains believed to be predominant in that winter, but the effectiveness of each year’s vaccine can vary considerably. Can you explain what an mRNA vaccine is and how it differs from vaccines for polio, flu, mumps, etc/?
DR. RAATH: Dr. Edward Jenner is commonly credited as the father of vaccines from his work in the late 1800s, but there are many stories from the 1500s (and even earlier) where immunity was triggered by exposing patients to a weakened form of the disease. We’ve managed to develop more scientific approaches to vaccines than crumbling dried-up scabs and blowing them up your nostril — as was apparently the practice in the Middle Ages!
Modern-day vaccines fall into a few groups:
1. Live attenuated vaccines: The virus is modified into a weaker form, but is still “live.” This type of vaccine cannot be used in pregnancy and certain types of immunocompromise, but it gives long-lasting immunity. Examples are measles and chickenpox (varicella) vaccines.
2. Inactivated vaccines: The virus gets used as a whole, but it gets killed first. This can be done chemically or by heat. The intact, but dead, virus is then used in the vaccine. It causes an immune response, but can’t replicate. An example is injected influenza vaccines.
3. Toxoids: Only the product of the organism is used. Tetanus or “lockjaw” vaccines are composed of the toxin/protein the bacteria that causes tetanus secretes.
4. Subunit/conjugate/recombinant vaccines: Only a component of the virus or bacteria is used, often a protein or sugar. Examples are hepatitis B and meningitis vaccines.
5. mRNA vaccines: Both of the vaccines as of now approved in Canada (Pfizer/BioNTech and Moderna) work by this mechanism. The instructions for assembling the outer spike protein are packaged in fat droplets and go to the part of the cell that makes proteins — the ribosomes. The ribosomes use the instructions to assemble spike proteins and then teach the immune system to recognize them. The instructions don’t stick around very long and don’t enter the nucleus where the DNA is housed.
6. Adenovirus vector vaccines (i.e. the AstraZeneca/Oxford COVID vaccine: The DNA coding the outer spike protein is adapted into an inactivated form of an adenovirus (one of the common cold viruses). Ultimately, you get a similar effect as the mRNA vaccines or the live attenuated vaccines, in that the host human cells produce the spike protein (just as happens if infected with the virus) and the immune system learns to recognize it and prevent future infection with the “whole” or “natural” virus.
DR. FENTON: There are different ways to produce vaccines and the viruses we target with vaccines have characteristics that make them more or less difficult to match. For example, for the influenza virus, the current mode of production is to look at epidemiological data and models for influenza strains circulating around the globe. Then an educated guess is made about which strains will still be circulating the following season. Those viruses are then grown in a lab before being killed and chopped up for the vaccine. Your body uses these bits of dead virus to produce protective antibodies.
However, in the time it takes to produce the vaccine and vaccinate the population, the circulating strains may change — either the virus itself changes genetically or a different virus may become more common in the meantime.
The mRNA vaccines take a different approach. Scientists were able to use the genetic code for the SARS-COV-2 virus to create messenger RNA, or the body’s instructions on how to make the spike protein for the SARS-COV-2 virus. Once injected, the body takes the mRNA and creates its own spike proteins for the immune system to take and make antibodies. This method is much faster than trying to grow the virus in the lab, so they were able to produce the vaccine much quicker.
The other advantage is that the spike protein is a key element of the COVID-19 virus that is unlikely to change, so we will likely have an excellent match to the virus for some time.
Q: Even if we get back to “normal” at some point after vaccinations begin, there remains the danger of the next new virus creating a new pandemic. Is there anything society can do collectively to reduce the risk of that happening?
DR. PARFITT: This is an inevitability, particularly given the way humans congregate and move across the globe and how we have encroached into animal environments. We can see that some parts of the world learned more from SARS in round one. They invested more in pandemic planning and mass testing strategies and adopted behaviours like masking as a cultural norm when experiencing respiratory symptoms.
There are so many examples of things we can do better next time, especially where it comes to informing changes in human behaviour. This was not really on most people’s radars and I wonder if we should learn about it in school — like how we have fire drills or talk about safety and planning in other forms of natural disasters. We have to invest more time and energy in pandemic planning on a global, national, provincial, local and personal level so that the next time might go smoother.
Vaccine development and subsequent clinical trials was a particularly slick part, but studying treatments and transmission was messy and we could have learned sooner which treatments are effective and better understood how it is spread. The importance of science communication, a basic understanding of statistics and media literacy cannot be understated. Many books will be written.
DR. FENTON: Public health specialists and virologists have been predicting this type of pandemic for years. Luckily we know many things that society can do to prevent them:
• Decrease the likelihood of zoonotic (animal to human) disease transmission by supporting habitat conservation efforts to decrease human interactions with wild animals and supporting food security and income-protection programs around the world to reduce the need to hunt and eat wild animals.
• Increase basic research funding. This includes basic laboratory research, but also community prevention. Currently, most researchers spend a lot of their time applying for funding grants. Their time can be used much more effectively for society’s benefit. Increase and stabilize funding for microbiology specialists so they can develop new testing and vaccine technology that can be ready when we need it.
• Increase or maintain funding for public health programs so they can plan for pandemic prevention and management and ensure they have trained staff. Governments often cut public health budgets when they don’t appear to be “needed,” which leaves us vulnerable, both because there is less ongoing prevention and our ability to respond.
• Ensure we have pandemic planning and response capacity at all levels of government, including internationally. Enhanced communication would have improved our understanding of the virus globally and would have improved the effectiveness of our response.
• Individual prevention measures. We’ve all learned the importance of staying home when sick, good hand washing and cough etiquette. Those are important to continue. Another important measure for everyone to think about is food safety. This includes washing your produce before you eat it and cooking foods to food-safe temperatures. We also each have the responsibility to ensure we are getting our information from reputable sources and helping our friends and family do the same.