Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Classification of countries by degree of public health significance of vitamin A deficiency (VAD). High- socio-demographic index (H-SDI), including countries with SDI ≥0.805; a lower confidence interval of VAD prevalence of ≥2% but <10% as mild; ≥10% but <20% as moderate; and ≥20% as severe areas of public health significance.
