span></span></code></pre></div>
<p><img src="aedseo_files/figure-html/unnamed-chunk-3-1.png" width="2187.5"></p>
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<div class="section level3">
<h3 id="determining-season">Determining season<a class="anchor" aria-label="anchor" href="#determining-season"></a>
</h3>
<p>Respiratory viruses can circulate in different seasons based on the
location. In the nordic hemisphere they mostly circulate in the fall and
winter seasons, hence surveillance is intensified from week 40 to week
20 in the following year. 