 immunity, but overshoots it!</strong> And it crosses the threshold <em>exactly</em> when current cases peak. (This happens no matter how you change the settings ‚Äì try it for yourself!)</p>

	<p>This is because when there are more <span class="nowrap">non-<icon s></icon>s</span> than the herd immunity threshold, you get R &lt; 1. And when R &lt; 1, new cases stop growing: a peak.</p>

	<p><strong>If there&#39;s only one lesson you take away from this guide, here it is</strong> ‚Äì it&#39;s an extr