gistfile1.html

  cartodb.createLayer(map, layerUrl, layerOptions)
    .addTo(this.map)
    .on('done', function(layer) {
      var sublayer = layer.getSubLayer(1),
          sublayer2 = layer.getSubLayer(0);

      sublayer.setInteractivity('cartodb_id, iso_a3, name');
      sublayer.setInteraction(true);

      sublayer.on('featureClick', function(e, latlng, pos, data, layerNumber) {
        // click
      });

      sublayer.on('featureOver', function(e, latlng, pos, data, layerNumber) {
        // over
        var iso = data.iso_a3,
            name = data.name;

        console.log(iso, name, pos);
      });

      sublayer.on('featureOut', function(e, latlng, pos, data, layerNumber) {
        // out
      });

    }).on('error', function() {
      // error
    });
}