diff --git a/etc/pyenv.d/which/system-site-packages.bash b/etc/pyenv.d/which/system-site-packages.bash
index 6bfb0aa..8283793 100644
--- a/etc/pyenv.d/which/system-site-packages.bash
+++ b/etc/pyenv.d/which/system-site-packages.bash
@@ -37,8 +37,12 @@ if [ ! -x "${PYENV_COMMAND_PATH}" ]; then
         if [ ! -f "${no_global_site_packages}" ]; then
           include_system_site_packages=1
         fi
+        virtualenv_orig_prefix="$(find "${virtualenv_libpath}/" -maxdepth 2 -type f -and -name "orig-prefix.txt" 2>/dev/null | head -1)"
+        if [ -f "${virtualenv_orig_prefix}" ]; then
+          virtualenv_prefix="$(cat "${virtualenv_orig_prefix}" 2>/dev/null || true)"
+        fi
       fi
-      if [ -n "${include_system_site_packages}" ]; then
+      if [ -n "${include_system_site_packages}" ] && [ -n "${virtualenv_prefix}" ]; then
         # virtualenv is created with `--system-site-packages`
         virtualenv_command_path="${virtualenv_prefix}/bin/${PYENV_COMMAND_PATH##*/}"
         if [ -x "${virtualenv_command_path}" ]; then