The General Population
Well, to end this epidemic at a minimum somewhere between 70% – 90% of all people will need antibodies to COVID-19 acquired in some manner – either through direct infection and recovery, or through vaccines. That is the target for what is called “Herd Immunity”. Here the objective is to reduce the available reservoirs of people without immunity to COVID-19 until the transmission rate is cut to zero. The fire is put out. To achieve this it is critical that immunity be spread across the population – but particularly among younger, healthier people who may not be at much risk for severe disease, but are a very high risk for spreading the virus (especially the infamous “super-spreaders” who we cannot know in advance).
But even when Herd Immunity is reached, there will always remain the danger of “flare-ups” in:
- the reservoirs of non-immunes – people that have not received a vaccine, or been infected naturally; and
- people whose immune systems are weakened – whether from old age or pre-existing conditions – and do not have strong immune protection from the virus; and
- from mutations of the virus which can partially evade the immunity from vaccines or previous exposure.
To generally prevent transmission in the broad, general population there is no doubt that vaccines are the best tool. They cost less, are easier to administer and – based on the efficacy data seen so far, as well as the history of respiratory viruses – should afford stable, long term protection. Again, mutations are a constant threat, but one we deal with in the case of the Flu vaccine every year.
Antibody-based therapeutics and drugs, on the other hand, afford short term protection. Unlike vaccines:
- the immunity is very rapidly boosted because you are giving people antibodies targeted at COVID-19 directly; BUT
- the immunity fades over time because they do not provoke an actual immune response, or any long term immune “memory” for the virus.
So, with the general population, we want to focus on long term immunity with vaccines, and use antibody-based therapeutics and drugs for protecting vulnerable population groups.
Vulnerable Population Groups
The tricky thing about COVID-19 is how different the outcomes can be. So many of us have seen neighbors, kids and celebrities all do just fine. Unfortunately, you cannot extrapolate from these data points. Age and underlying health conditions are hugely important factors influencing disease severity.
- A study of more than 1.3 million COVID-19 cases in the United States, published June 15 in the journal Morbidity and Mortality Weekly Report, found that rates of hospitalizations were six times higher and rates of death were 12 times higher among COVID-19 patients with underlying conditions, compared with patients without underlying conditions. The most commonly reported underlying conditions were heart disease, diabetes and chronic lung disease.
- About 8 out of 10 deaths associated with COVID-19 in the U.S. have occurred in adults ages 65 and older, according to the U.S. Centers for Disease Control and Prevention (CDC). The risk of dying from the infection, and the likelihood of requiring hospitalization or intensive medical care, increases significantly with age. For instance, adults ages 65-84 make up an estimated 4-11% of COVID-19 deaths in the U.S, while adults ages 85 and above make up 10-27%.
- These trends tend to overlap because so many elderly people have the exact chronic medical conditions that can exacerbate the symptoms of COVID-19, according to the CDC. The ability of the immune system to fight off pathogens also declines with age, leaving elderly people vulnerable to severe viral infections.
- Why COVID-19 kills some people and spares others. Here’s what scientists are finding.
- How Antibodies Help Your Body Beat COVID-19
The Long Term Role for Antibodies
So, when we look at all we have learned about COVID-19 over the the course of 2020, and what we know from our long experience dealing with respiratory viruses like the Flu and the Coronavirus cousins called “the Common Cold,” these factors stand out:
- COVID-19 is likely here to stay, and will continue to circulate – and perhaps also mutate – much like the seasonal Flu;
- the rate of death and severe disease is low among the general population, which will likely lead to lower than optimal rates of compliance with vaccination and public health best practices; and
- vulnerable population groups, who do have high risk of severe disease and/or death and are likely to not be fully protected by vaccines, will continue to be exposed and sickened in flare-ups.
Given this, antibody-based therapeutics and treatments have an important long term role to play in several ways for vulnerable population groups.
- For those that are proactive, providing an “immunity boost” prophylactically when there is high risk of exposure. Generally, during the winter months, but also when traveling, going to family gatherings, big social events and crowds, have workplace environments with high social interaction, etc.
- When there are outbreaks, quickly responding to boost immunity to vulnerable individuals who have significant risk of exposure, as well as quickly treating those that have been exposed. Vaccines are not generally effective when given after a person has already been exposed to a respiratory virus because it typically takes a few weeks for the body to build immunity after vaccination. So, currently antibodies are the best option to reduce the chance of severe disease – but only when given rapidly after exposure.
This depends, however, on:
- ramping up production and distribution of antibody-based therapeutics and drugs;
- raising awareness in the medical community and public for their importance, and how they should be used; and
- establishing protocols and processes for rapid response after confirmation of infection in the one case, and prophylactic treatment in the second.
- Coronavirus Prevention Network: The Science of COVID-19 Vaccines and Antibodies
- NIH: The COVID-19 Treatment Guidelines Panel’s Statement on the Emergency Use Authorization of Bamlanivimab for the Treatment of COVID-19
- CDC: Benefits of Getting a COVID-19 Vaccine
This video from the Coronavirus Prevention Network provides a great quick summary.