〒180-0006 東京都武蔵野市中町2-3-5 IIHA武蔵野1階
Dear MEL Topic Readers,
As new COVID variants emerge, is herd immunity impossible?
The pandemic and race for vaccination have shown health inequalities around the world. While wealthy countries are accelerating vaccination and even a booster shot to protect their citizens against coronavirus, poorer countries are struggling to get essential workers vaccinated. Vaccines offer better protection than natural infection, with antibodies lasting longer and being more effective against serious illness. In fact, they have controlled contagious diseases like smallpox, polio, diphtheria, and pertussis effectively. But in order to contain an infectious disease like the coronavirus, it is necessary to achieve herd immunity, which occurs when a large proportion of a population becomes protected against or immune to infection. Once achieved, herd immunity can significantly reduce the spread of infections among both vaccinated and unvaccinated people. However, as for Covid-19, it is not clear how effective antibodies acquired through natural infection are, how long they last, or if people catch the coronavirus more than once. Also, as more new variants appear, the efficacy of the current vaccination or the level of herd immunity needs to be reviewed. Indeed, there are various aspects to maintain the efficacy of the vaccination.
Enjoy reading the article and learn about what makes the vaccination effective against the novel virus.