diff --git a/CHANGELOG.md b/CHANGELOG.md
index e02ae4874..d3194d6e4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -13,6 +13,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
+- Fixed an issue in the global heat map component caused by manipulating an input property
 - Fixed an issue with the currency inconsistency in the _EOD Historical Data_ service (convert from `GBX` to `GBp`)
 
 ## 1.256.0 - 2023-04-17
diff --git a/apps/client/src/app/components/world-map-chart/world-map-chart.component.ts b/apps/client/src/app/components/world-map-chart/world-map-chart.component.ts
index 9d7c61d62..62774edf2 100644
--- a/apps/client/src/app/components/world-map-chart/world-map-chart.component.ts
+++ b/apps/client/src/app/components/world-map-chart/world-map-chart.component.ts
@@ -30,6 +30,9 @@ export class WorldMapChartComponent implements OnChanges, OnDestroy, OnInit {
   public ngOnInit() {}
 
   public ngOnChanges() {
+    // Create a copy before manipulating countries object
+    this.countries = structuredClone(this.countries);
+
     if (this.countries) {
       this.isLoading = true;