diff --git a/src/app/voyager/MyMap.tsx b/src/app/voyager/MyMap.tsx
index 9bcdfc58..fbc67bca 100644
--- a/src/app/voyager/MyMap.tsx
+++ b/src/app/voyager/MyMap.tsx
@@ -10,6 +10,7 @@ const CountriesDisastersMap: React.FC = () => {
   const router = useRouter();
 
   useEffect(() => {
+    if (geoJSON) return;
     // サンプルとして固定されたパスのGeoJSONを取得
     const year = "2024";
     const month = "12";
diff --git a/src/app/voyager/[country]/page.tsx b/src/app/voyager/[country]/page.tsx
index 1b07e191..13da3ac3 100644
--- a/src/app/voyager/[country]/page.tsx
+++ b/src/app/voyager/[country]/page.tsx
@@ -23,6 +23,7 @@ const CountryDisasters: React.FC = () => {
 
   useEffect(() => {
     if (!country) return;
+    if (disasters && disasters.length > 0) return;
 
     const fetchDisasters = async () => {
       setLoading(true);