diff --git a/vignettes/contacts.Rmd b/vignettes/contacts.Rmd
index 1f9a7072793a5aeef1fad41f8f3c309c76a5887d..a540c83fdafc0b36e956e6362aac1b6ca5e78157 100644
--- a/vignettes/contacts.Rmd
+++ b/vignettes/contacts.Rmd
@@ -43,6 +43,8 @@ knitr::knit_hooks$set(
   }
 )
 
+Sys.setlocale("LC_TIME", "C")
+
 ```
 
 ```{r setup, echo=FALSE, message=FALSE}
@@ -176,7 +178,7 @@ The following code generates a plot with the gamma distribution of the illness p
 ```{r visualization of get_infection_date_density, foldcode=TRUE}  
   g <- ggplot() +
 
-    scale_x_datetime(breaks = scales::date_breaks("1 days"), labels = scales::date_format("%d-%m-%Y")) +
+    scale_x_datetime(breaks = scales::date_breaks("1 days"), labels = scales::date_format("%d %b")) +
     theme(axis.text.x = element_text(angle = 90)) +
     # scale_x_continuous(breaks = x_tick,
     #                    labels = x_label) +
diff --git a/vignettes/contagious_period.Rmd b/vignettes/contagious_period.Rmd
index e52c1a82e879fd5fad299335ee85b6be0a4c1d8f..2464022e7821dd64744b8e6352845c13c9917789 100644
--- a/vignettes/contagious_period.Rmd
+++ b/vignettes/contagious_period.Rmd
@@ -43,6 +43,8 @@ knitr::knit_hooks$set(
   }
 )
 
+Sys.setlocale("LC_TIME", "C")
+
 ```
 
 ```{r setup, echo=FALSE, message=FALSE}
@@ -147,7 +149,7 @@ period_95 <- .calculate_qstart_qend(0.95, infectious_df_v1)
 ```{r visualization of get_infection_density, foldcode=TRUE}  
   g <- ggplot() +
 
-    scale_x_datetime(breaks = scales::date_breaks("1 days"), labels = scales::date_format("%d-%m-%Y")) +
+    scale_x_datetime(breaks = scales::date_breaks("1 days"), labels = scales::date_format("%d %b")) +
     theme(axis.text.x = element_text(angle = 90)) +
     # scale_x_continuous(breaks = x_tick,
     #                    labels = x_label) +
diff --git a/vignettes/future_infections.Rmd b/vignettes/future_infections.Rmd
index 4d298af38bcd04c1548aa1f4a87e94647c298ece..09fc0ab1980f153add6cfe62e8a4e669a59127e8 100644
--- a/vignettes/future_infections.Rmd
+++ b/vignettes/future_infections.Rmd
@@ -43,6 +43,8 @@ knitr::knit_hooks$set(
   }
 )
 
+Sys.setlocale("LC_TIME", "C")
+
 ```
 
 ```{r setup, echo=FALSE, message=FALSE}
diff --git a/vignettes/infection_period.Rmd b/vignettes/infection_period.Rmd
index 5a008f64b1c9371a354edefc94d6ab65b0afd081..b9a74d8b58bcb869730069785e21c865f4ea73d0 100644
--- a/vignettes/infection_period.Rmd
+++ b/vignettes/infection_period.Rmd
@@ -43,6 +43,8 @@ knitr::knit_hooks$set(
   }
 )
 
+Sys.setlocale("LC_TIME", "C")
+
 ```
 
 ```{r setup, echo=FALSE, message=FALSE}
@@ -178,7 +180,7 @@ knitr::kable(infec_date_df_v2[100:109,],
 ```{r visualization of get_infection_density, foldcode=TRUE}  
   g <- ggplot() +
 
-    scale_x_datetime(breaks = scales::date_breaks("1 days"), labels = scales::date_format("%d-%m-%Y")) +
+    scale_x_datetime(breaks = scales::date_breaks("1 days"), labels = scales::date_format("%d %b")) +
     theme(axis.text.x = element_text(angle = 90)) +
     # scale_x_continuous(breaks = x_tick,
     #                    labels = x_label) +
@@ -231,7 +233,7 @@ knitr::kable(infec_date_df_v2[100:109,],
 ```{r visualization of get_misc_infection_density, foldcode=TRUE}  
   g <- ggplot() +
 
-    scale_x_datetime(breaks = scales::date_breaks("1 days"), labels = scales::date_format("%d-%m-%Y")) +
+    scale_x_datetime(breaks = scales::date_breaks("1 days"), labels = scales::date_format("%d %b")) +
     theme(axis.text.x = element_text(angle = 90)) +
     # scale_x_continuous(breaks = x_tick,
     #                    labels = x_label) +
diff --git a/vignettes/risk_assessment_group_quarantine.Rmd b/vignettes/risk_assessment_group_quarantine.Rmd
index df0155ea609ff6537bdbee5027d5a95fd29bf255..15af706a775e448913784e9c1c1b0363a8e00c72 100644
--- a/vignettes/risk_assessment_group_quarantine.Rmd
+++ b/vignettes/risk_assessment_group_quarantine.Rmd
@@ -43,6 +43,8 @@ knitr::knit_hooks$set(
   }
 )
 
+Sys.setlocale("LC_TIME", "C")
+
 ```
 
 ```{r setup, echo=FALSE, message=FALSE}