Answer:

I contacted WHOIS (World Health Organization Statistical Information
System) with your enquiry and they suggest you to begin by looking at
the WHOSIS (WHO Statistical Information System) at
http://www3.who.int/whosis where there are many databases, as well as the possibility to search by keyword throughout the entire WHO website. Many WHO technical programmes make data available via this forum and, if so, you will be led to them.

Under "Statistics by Disease or Condition"
http://www3.who.int/whosis/links/diseases_links.cfm?path=whosis,diseases_links&language=english#20
in the WHOSIS you will find links to statistical information available throughout WHO's technical programmes. Organized by disease, condition or topic.

Under "External sources for health-related statistical information"
http://www3.who.int/whosis/links/external_links.cfm?path=whosis,external_links&language=english
in the WHOSIS you will also find additional, health-related search possibilities outside of WHO, such as CDC (Centers for Disease Control
and Prevention), Demographic and Health Surveys, NLM (US National
Library of Medicine), etc.
Under "Links to National Health-Related Websites"
http://www3.who.int/whosis/national_sites/index.cfm?path=whosis,links,links_national&language=english
you will find a collection of links to Ministries of Health and/or
Central Statistics Offices (where available).

The WHO World Health Report is available online at
http://www.who.int/whr.
Its Statistical Annex contains Basic indicators, Healthy Life
Expectancy (HALE), Selected National Health Accounts indicators for all Member States, etc. Also, Deaths and Burden of Disease (DALYs) in WHO Regions.

Who's Regional Offices often have more detailed country information.
Contact information for WHO Regional Offices can be found at
http://www.who.int/regions.

Who is a very large organization. As you explore our many web pages
you will find contact information for persons within the technical areas
which are of interest to you, and whom you should contact for further
or more detailed information.

Much of the information developed by WHO appears in its publications.
The publications catalogue can be accessed on http://www.who.int/dsa,
where you will also find instructions for placing orders. To receive a
copy of the WHO publications catalogue by mail, send your postal
address to: publications@who.ch. The WHO Library can be accessed on
http://www.who.int/hlt, where you will find instructions for obtaining
WHO publications and documents.

From the main WHO web site it is now possible to search for information
by Health Topic [http://www.who.int/health_topics/en/], and by Country
[http://www.who.int/country/en/]. A much-improved search engine is also now available [http://www.who.int/search].

I hope this will give you enough information, if you need any
clarification please do not exitate to ask