C# XmlSerializer, edit XML file without rewriting the whole file

I am currently working on a C# app, that has to serialize some simple object into a given XML file.

For example, here is a simple example class... Let's say Human

   public class Human
    {
        private XmlSerializer serializer = new XmlSerializer(typeof(Human));

        public string name { get; set; }
        public int age { get; set; }
        public string country { get; set; }

        public void Serialize()
        {
            StreamWriter stream = null;

            try
            {
                stream = new StreamWriter("data.xml");
                serializer.Serialize(stream, this);
                stream.Close();
            }
            catch (Exception e)
            {
                if (stream != null)
                {
                    stream.Close();
                }
            }
        }
    }

If I instanciate this class, set some values, and call the Serialize() method, my data.xml file will look as follows :

<?xml version="1.0" encoding="utf-8"?>
<Human xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <name>Oscar</name>
  <age>20</age>
  <country>France</country>
</Human>

Now imagine that I have an object that contains a List of Human. Serializing this object will take time and ressources, and will generate a pretty big XML file.

If I wan't to edit a specific Human, or simply add a new one to my List, is there a way to edit/modify only a small part of the XML file ? Or do I have to re-serialize again the whole List and replace the XML file content ?