Ow effective has the World Health Organization performed its main functions when dealing with international pandemics?

How effective has the World Health Organization performed its main functions when dealing with international pandemics?
Main functions being:
1. providing global leadership and management in health related issues
2. Shaping global norms and standards for health, and promote their implementation.
3. Creating partnerships with governments in strengthening national health programmes and policies
4. providing technical support and transfer appropriate health technology & information

The essay has to be in relation to specifically INTERNATIONAL HEALTH SECURITY Global health security policies. The course is about international security in a borderless world. Health threats as global security threats due to issues like globalization etc.