In my two other posts, I wrote about my personal experience with COVID-19 vaccination along with the pain and side effects that I felt at the time. Here, as a clinician, I would like to consider the effect that COVID-19 vaccination will have on our daily life from now on.
What's next in the COVID-19 pandemic?
It is not possible to say anything certain now, but in Israel and the UK, countries that started vaccination early, and in the US where the pandemic has been the most severe, we can say that the daily number of new cases has dramatically declined1). Furthermore, considering the report that neutralizing antibodies remain at high levels in the blood for six months after vaccination2), if vaccination increases throughout the world, it is not an overstatement to say that achieving a state close to herd immunity throughout humankind becomes a possibility. However, we are still a long way from reaching a situation like that of smallpox, a virus which has been eradicated, or polio which occurs now only in small outbreaks. Dr. Anthony Fauci, Director of the National Institute of Allergy and Infectious Diseases (NIAID) in the United States also foresees seasonal outbreaks in various parts of the world in the future. Furthermore, if the virus endures, there is a high possibility of the appearance of a high infectious variant, and he foresees that vaccination may be necessary every two years or so.
A major reason for the ongoing outbreaks around the world is the fact that in any country there is a portion of the population that does not wish to be vaccinated and the virus survives by infecting such people. It is possible that over 30% of the population of the United States are not willing to get vaccinated. Dr. Fauci has somewhat pessimistically noted that it may not be possible to achieve herd immunity as a country (in the United States)3).
After Vaccination, Nearly Everyone Returns to Daily Life without a Mask
The Centers for Disease Control and Prevention (CDC) has already announced that those who have completed vaccination (twice for Pfizer or AstraZeneca vaccines and once for the Johnson & Johnson vaccine) do not need to wear a mask in daily life. If herd immunity is achieved, the possibility of an unvaccinated person becoming infected with COVID-19 is also reduced. However, unlike the vaccinated person, the unvaccinated person is unable to resist the virus, so if there is an outbreak of COVID-19, the possibility of infection always exists.
Most Japanese are vaccinated for measles during childhood, but even if they are not vaccinated for various reasons, if they are surrounded by others who have been vaccinated, there is little likelihood that they will come in contact with the virus, and consequently, they will not be infected. This also applies in the case of the COVID-19 vaccine. If a majority of people (60-70%) are vaccinated, those who are not vaccinated will be indirectly protected from infection.
As such, even if vaccination is declined, after a while, the possibility of COVID-19 infection drops. Side effects are a concern, and there is the option of not receiving the vaccine and waiting for herd immunity to be achieved, but those who make this choice will also have to bear the inconvenience of being unable to travel abroad for some time (at least for a few years). WHO is also considering making international vaccine passports that would serve as permits for foreign travel, and some countries and regions have already begun using such permits.
It may seem unfair to prohibit the unvaccinated from travelling abroad, but this is not limited to COVID-19 nor it is unprecedented. There are stil cases where international travel is not allowed unless passengers have been vaccinated. For example, unless one is vaccinated for yellow fever, travel is not allowed to countries in Africa and parts of South America where yellow fever is prevalent. In the past, I visited Ghana several times on business for JICA, and because it was necessary to have a certificate of vaccination upon entering the country, I received the rather painful yellow fever vaccination.
Neutralizing Antibodies in Mother's Milk
A study conducted in Israel on the vaccination of lactating mothers has found that their breastmilk contains a significant level of a coronavirus antibody (IgA). Vaccinations have not yet been extended to children 12 years old and younger, but this indicates the possibility that a mother with a child who is breastfeeding protects not only herself, but also her child from COVID-19 infection4).
It is not a vaccination with an attenuated, living virus (which then lightly infects) like the vaccines for measles or rubella. The new COVID-19 vaccine uses mRNA for which there is no possibility of reproduction, and once its safety is confirmed, I foresee that vaccination of even expectant mothers will eventually begin.
There are not many in Japan who have a bright outlook of the future given the situation with the Olympic games, the ongoing fourth outbreak, and the slow rate of vaccination. In UK and Israel, where the vaccination started early, people are starting to view the future more optimistically. Let's hope that Japan will catch up with these other nations soon.
- 1) Daily New Cases in the United States. Worldometer.
https://www.worldometers.info/coronavirus/country/us/#graph-cases-daily - 2) Doria-Rose N, Suthar MS, Makowski M, O'Connell S, McDermott AB, Flach B, Ledgerwood JE, Mascola JR, Graham BS, Lin BC, et al.; mRNA-1273 Study Group. Antibody persistence through 6 months after the second dose of mRNA-1273 vaccine for Covid-19. N Engl J Med. 2021. doi:10.1056/NEJMc2103916.
- 3）Public Trust and Willingness to Vaccinate Against COVID-19 in the US From October 14, 2020, to March 29, 2021. Michael Daly, Andrew Jones, Eric Robinson. JAMA. Published online May 24, 2021.doi:10.1001/jama.2021.8246
- 4) SARS-CoV-2-Specific Antibodies in Breast Milk After COVID-19 Vaccination of Breastfeeding Women, Sivan Haia Perl, et al. JAMA. 2021;325(19):2013-2014. doi:10.1001/jama.2021.5782
Yoichi Sakakihara
