diff --git a/cara/apps/calculator/model_generator.py b/cara/apps/calculator/model_generator.py
index 06c29229..61f4e9fd 100644
--- a/cara/apps/calculator/model_generator.py
+++ b/cara/apps/calculator/model_generator.py
@@ -117,7 +117,7 @@ class FormData:
         'simulation_name': _NO_DEFAULT,
         'total_people': _NO_DEFAULT,
         'ventilation_type': 'no_ventilation',
-        'virus_type': 'SARS_CoV_2',
+        'virus_type': 'SARS_CoV_2_B16172',
         'volume_type': _NO_DEFAULT,
         'window_type': 'window_sliding',
         'window_height': 0.,
diff --git a/cara/apps/calculator/templates/calculator.form.html.j2 b/cara/apps/calculator/templates/calculator.form.html.j2
index c119d4e5..97209c98 100644
--- a/cara/apps/calculator/templates/calculator.form.html.j2
+++ b/cara/apps/calculator/templates/calculator.form.html.j2
@@ -62,10 +62,10 @@ v{{ calculator_version }} <span style="float:right; font-weight:bold">Please sen
     <div class="row">
         <label class="col-xl-3 col-lg-4 col-sm-3 col-form-label">Variant:</label>
         <select id="Variant" name="virus_type" class="col-xl-5 col-lg-7 col-sm-7 col-7">
+          <option value="SARS_CoV_2_B16172">SARS-CoV-2 (Delta VOC)</option>
           <option value="SARS_CoV_2">SARS-CoV-2 (nominal strain)</option>
           <option value="SARS_CoV_2_B117">SARS-CoV-2 (Alpha VOC)</option>
           <option value="SARS_CoV_2_P1">SARS-CoV-2 (Gamma VOC)</option>
-          <option value="SARS_CoV_2_B16172">SARS-CoV-2 (Delta VOC)</option>
         </select>
     </div>
 
@@ -344,13 +344,13 @@ v{{ calculator_version }} <span style="float:right; font-weight:bold">Please sen
   <b>Quick Guide:</b><br>
   This tool simulates the long range airborne spread SARS-CoV-2 virus in a finite volume and estimates the risk of COVID-19 infection. It is based on current scientific data and can be used to compare the effectiveness of different mitigation measures.<br>
   <b>Virus data:</b> <br>
-  SARS-CoV-2 covers typical strains of the virus and three variants of concern (VOC):<br>
+  SARS-CoV-2 covers the original wild strain of the virus and three variants of concern (VOC):<br>
   <ul>
     <li>Alpha (also known as B.1.1.7, first identified in UK, Dec 2020),</li>
     <li>Gamma (also known as P.1, first identified in Brazil/Japan, Jan 2021).</li>
     <li>Delta (also known as B.1.617.2, first identified in India, Oct 2020).</li>
   </ul>
-  Choose variant according to local area prevalence, e.g. for <a href="https://www.covid19.admin.ch/fr/epidemiologic/virus-variants?detGeo=GE">Geneva</a>
+  Modify the default (Delta) as necessary, according to local area prevalence e.g. for <a href="https://www.covid19.admin.ch/fr/epidemiologic/virus-variants?detGeo=GE">Geneva</a>
   or <a href="https://www.santepubliquefrance.fr/dossiers/coronavirus-covid-19/covid-19-cartographie-des-variants-en-france-donnees-par-region-et-par-departement">Ain (France)</a>.<br>
   <b>Ventilation data:</b> <br>
   <ul>
diff --git a/cara/apps/calculator/templates/userguide.html.j2 b/cara/apps/calculator/templates/userguide.html.j2
index ede8c8e3..ac0e69ca 100644
--- a/cara/apps/calculator/templates/userguide.html.j2
+++ b/cara/apps/calculator/templates/userguide.html.j2
@@ -56,12 +56,12 @@ Changing this setting alters the properties of the virus which are used for the
 This has a significant effect on the probability of infection. 
 The choices are:</p>
 <ul>
-<li><code>SARS-CoV-2 (nominal strain)</code>, covering typical strains and varaints which are not of concern from an epidemiologic point of view of the virus;</li>
+<li><code>SARS-CoV-2 (nominal strain)</code>, covering typical strains and variants which are not of concern from an epidemiologic point of view of the virus;</li>
 <li><code>SARS-CoV-2 (Alpha VOC)</code>, first identified in the UK at the end of 2020 which is found to be approximately 1.5x more transmissible compared to the non-VOCs; </li>
 <li><code>SARS-CoV-2 (Gamma VOC)</code>, first identified in Brazil in January 2021 which is found to be approximately 2.2x more transmissible compared to the non-VOCs.</li>
 <li><code>SARS-CoV-2 (Delta VOC)</code>, first identified in India towards the end of 2020 which is found to be approximately 60% more transmissible compared to the ALPHA VOC.</li>
 </ul>
-<p>The user can base their choice according to the prevalence of the different variants in the local area. Access to this information can be found here:</p>
+<p>The user can modify the selected variant from the default (Delta VOC), according to the prevalence of the different variants in the local area. Access to this information can be found here:</p>
 <ul>
 <li>Geneva: <a href="https://www.covid19.admin.ch/fr/epidemiologic/virus-variants?detGeo=GE">https://www.covid19.admin.ch/fr/epidemiologic/virus-variants?detGeo=GE</a></li>
 <li>Ain (France): <a href="https://www.santepubliquefrance.fr/dossiers/coronavirus-covid-19/covid-19-cartographie-des-variants-en-france-donnees-par-region-et-par-departement">https://www.santepubliquefrance.fr/dossiers/coronavirus-covid-19/covid-19-cartographie-des-variants-en-france-donnees-par-region-et-par-departement</a></li>