“The development of a safe, effective and cheap vaccine, however, is only a first step towards community-wide control. Epidemiological, economic and motivational issues are at least as important as technological ones.” Nature, 1985
Vaccine implementation defines the efficacy of vaccines role in influencing a pandemic. How, when, to whom, by whom, where, why, timescale are just a few initial questions when considering implementation. The logic that ‘more vaccines = less disease’ is not only incorrect but can lead to unwanted results. In essence vaccines are not silver bullets, the hard work of coordinated viral containment still needs doing.
“the benefits of many current vaccines extend beyond the direct benefits to indirect benefits, i.e. through the herd effect extending beyond targeted groups to other populations at high risk for complications. Nevertheless, gaps in our knowledge exist about how best to achieve herd immunity. For example, it is unclear whether there are particular formulations that confer better herd immunity than others; a prime example is whether herd immunity achieved through live attenuated influenza vaccine is superior to that achieved with inactivated vaccine. Another area where gaps in our knowledge exist is the optimal use of new vaccines. For example, there are several candidate vaccines for dengue in clinical trials and strategies for how best to use them to establish herd immunity need to be developed.” Vaccine Herd Effect 2011
One key dimension to developing an appropriate public health programme that recognises this complexity is to understand the building blocks of this complexity. Whilst not the primary one, a primary building block is the vaccine used.
“Research efforts should be directed towards enhancing existing vaccines or developing new vaccines that also protect against asymptomatic infections and onward transmission. Until we have such vaccines, public health and social measures will still need to be tailored towards mitigating community and household transmission in order to keep the pandemic at bay.” Lancet, October 2021
I have asked Independent Sage:
“Do certain types of vaccine (e.g. inactivated, live attenuated etc) reduce transmission or reduce/stop people being infectious more than other types? Or ‘vaccine type’ does not correlate with transmission. I have expertise in the social dimensions of transmission but at a biological level I am unclear.”
- Inactivated vaccines
- Live-attenuated vaccines
- Messenger RNA (mRNA) vaccines
- Subunit, recombinant, polysaccharide, and conjugate vaccines
- Toxoid vaccines
- Viral vector vaccines
The Ministry of Health in Cuba has and is developing a number of vaccines that are of a different type to those currently dominating the ‘covid vaccine market’. We already know that they do not require such expensive storage and one takes the form of a nasal spray. This minor attributes do not define what is possible but do open radically different possibilities that currently seen. Most important is whether any of the multiple Cuban vaccines perform significantly better at lowering transmission. Even if they do not, a nasal spray opens up some very interesting possibilities for easier coordination and containment of the pandemic.
“To really nail down whether vaccines prevent transmission, researchers are tracking the close contacts of vaccinated people to see whether they are being indirectly protected from infection.” Smriti Mallapaty, Nature Feb 2021
Thinking beyond vaccination:
“No-COVID strategy… First, a rapid reduction in numbers of infections to zero. Second, avoidance of further virus transmission or reintroduction through rigorous test, trace, and isolate systems, together with local travel restrictions. Third, rapid outbreak management if new cases of COVID-19 occur sporadically…
Myths that have come to distort public and political debate about how to manage this pandemic…. There is a trade-off between health and the economy. No: the fate of our wellbeing and our wider lives go hand-in-hand. We can protect vulnerable groups. Practically, given the vast numbers who are vulnerable, impossible. COVID-19 only concerns the elderly. Even among a younger population, COVID-19 is harmful, sometimes deadly. Once infected, people are forever immune. We simply don’t know, but unlikely. Only vaccination will save us. Over time, maybe, but not in the short term. Herd immunity can be achieved by infection. Neither a feasible nor a desirable strategy. Closing schools is more stressful for children and families than keeping them open. What may matter more is scaled up educational and economic support. Vaccinations will end the COVID-19 pandemic quickly. Sadly, not for some time. ” Horton, Lancet, Jan 2021
“A multi-disciplinary effort to eliminate Covid-19. An international volunteer coalition and networking hub that develops and promotes community-based solutions for policy-makers, businesses and individuals.” EndCoronaVirus.org
“The Zero Covid campaign’s mission is to make [zero covid a] reality. It is a democratic, activist campaign of individual supporters and affiliated organisations.” Zero Covid Coalition UK
“No-COVID: Controlling the Covid-19 pandemic through Green Zones” No Covid EU
Thinking of the UK government:
“[Ferguson et al] ignore standard Contact Tracing allowing isolation of infected prior to symptoms. They also ignore door-to-door monitoring to identify cases with symptoms. Their conclusions that there will be resurgent outbreaks are wrong. After a few weeks of lockdown almost all infectious people are identified and their contacts are isolated prior to symptoms and cannot infect others. The outbreak can be stopped completely with no resurgence.” Shen, Taleb, Bar-Yam March 2020
Ferguson and Imperial College Covid Response Team March 2020
The modelling by Ferguson et al. defined how the UK government addressed the pandemic from the beginning. As indicated in the illustration further peaks in infection have been expected all along as an effective test and trace strategy is not part of the government’s plan, but instead to wait it out until vaccination. However, vaccination is not the silver bullet it is imagined to be with variants etc. In essence the restrictions coming in now were entirely predictable and entirely avoidable. It is also somewhat ironic that the government hired the same lineage of scientists who mismanaged Foot and Mouth disease to define their pandemic response.
Also to keep in mind, even if the pandemic were contained in humans, it might resurge from a populations of non-human animals. Nature March 2021
I would like to use these notes to begin a long term analysis of possible scenarios.
Avi 