React app with nodejs/express server and mysql database doesn't load data right away when first visiting the home page. Related to mysql connection

I have an app with the server hosted on heroku where 15 of the latest entries in the database should show up when going to the home page. I have a a conifg.js file where I establish a connection to the database. The code used to be

const mysql = require('mysql');

const db = mysql.createConnection({
    host: 'host',
    database: 'db',
    user: 'user',
    password: 'password',
});
module.exports = db;

This was loading the latest entries on the home page properly on first visit but my app was experiencing crashes due to I believe it trying to query without there being a connection? Not entirely sure. I changed this code to

const mysql = require('mysql');

  let connection=null;
  function handleDisconnect() {
      connection = mysql.createConnection({
          host: "host",
          user: "user",
          password: "password",
          database: "db"
      }); // Recreate the connection, since
      // the old one cannot be reused.
  
      connection.connect(function (err) { // The server is either down
          if (err) { // or restarting (takes a while sometimes).
              console.log('error when connecting to db:', err);
              setTimeout(handleDisconnect, 2000); // We introduce a delay before attempting to reconnect,
          } // to avoid a hot loop, and to allow our node script to
      }); // process asynchronous requests in the meantime.
      // If you're also serving http, display a 503 error.
      connection.on('error', function (err) {
          console.log('db error', err);
          if (err.code === 'PROTOCOL_CONNECTION_LOST') { // Connection to the MySQL server is usually
              handleDisconnect(); // lost due to either server restart, or a
          } else { // connnection idle timeout (the wait_timeout
              throw err; // server variable configures this)
          }
      });
  }
  handleDisconnect();
  setInterval(function () {
      connection.query('SELECT 1');
  }, 5000);
  
  module.exports = connection;

My app is no longer crashing but is experiencing a delay in retrieving data from the database. Not sure what changes to make to handle both the crash issue as well as the delay when loading the page.

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