Severe wasting among children under 5 years of age

Percent/numbers

Child growth is an internationally accepted outcome reflecting child nutritional status. Child wasting refers to a child who is too thin for his or her height and is the result of recent rapid weight loss or the failure to gain weight. A child who is moderately or severely wasted has an increased risk of death, but treatment is possible. Child wasting is one of the World Health Assembly nutrition target indicators. Child growth is the most widely used indicator of nutritional status in a community and is internationally recognized as an important public-health indicator for monitoring health in populations. In addition, children who suffer from growth retardation as a result of poor diets and/or recurrent infections tend to have a greater risk of suffering illness and death

Prevalence of severe wasting (weight for height <-3 standard deviation from the median of the World Health Organization (WHO) Child Growth Standards) among children under 5 years of age.

Numbers affected (thousands) of severe wasting (weight for height <-3 standard deviation from the median of the World Health Organization (WHO) Child Growth Standards) among children under 5 years of age

Country, regional and worldwide JME global estimates refer to the age group of children under 5 years, sexes combined. Disaggregates are currently not available for the JME global estimates. However, the survey-based estimates are compiled in a disaggregated dataset of national primary sources with sub national and stratified estimates (e.g. sex, age groups, wealth, mothers' education, residence).

Methods and Guidance:

WHO and UNICEF provide recommendations for data collection, analysis and reporting on anthropometric indicators in children under 5 years old. (Recommendations for data collection, analysis and reporting on anthropometric indicators in children under 5 years old. Geneva: World Health Organization and the United Nations Children’s Fund (UNICEF), 2019. Licence: CC BY-NC-SA 3.0 IGO. )

Analysis Tool

To facilitate re-running of nutritional survey data based on standardized approach, WHO has developed an online tool to analyse child anthropometric data. The WHO Anthro Survey Analyzer aims to promote best practices on data collection, analyses and reporting of anthropometric indicators. It offers analysis for four indicators: length/height-for-age, weight-for-age, weight-for-length, weight-for-height and body mass index-for-age. (WHO Anthro Survey Analyser and other tools)

Impact

Data collection method

UNICEF and WHO employ their existing networks to obtain data. WHO relies on the organization’s structure and an expanding network developed following the creation of the WHO Global Database on Child Growth and Malnutrition. For UNICEF, the cadre of dedicated data and monitoring specialists working at national, regional and international levels in 190 countries routinely provides technical support to produce child malnutrition estimates through surveys and administrative systems and analyses for improved programme planning. The World Bank Group provides estimates available through the Living Standard Measurement Surveys (LSMS).

A well-established methodology for deriving global and regional trends and forecasting future trends, have been published. The trend estimation uses a linear mixed-effect model allowing for random effects at country level and for heterogeneous covariance structures. The basic model contains the factors sub-region, year, and the interaction between year and the sub-region as fixed effects with country as a random effect. ( The UNICEF-WHO-World Bank Joint Child Malnutrition Estimates (JME) standard methodology New York: the United Nations Children’s Fund (UNICEF), the World Health Organization and the World Bank, 2024. Licence: CC BY-NC-SA 3.0 IGO.)

Data sources are updated in the WHO Global Database for Child Growth and Malnutrition a continuous basis to feed into the annual production of global and regional estimates and updated country level dataset released every March.

For more information about contributing to the WHO Global Database for Child Growth and Malnutrition, please review the “Identification of data sources section” on the Methodology Page (WHO Department of Nutrition and Food Safety – Joint Child Malnutrition Estimates)

The UNICEF-WHO-WB Joint Child Malnutrition (JME) group releases country, regional and worldwide estimates at the end of March of uneven years so that data are available for reporting on the Sustainable Development Goals (SDGs). ( The UNICEF-WHO-World Bank Joint Child Malnutrition Estimates (JME) standard methodology New York: the United Nations Children’s Fund (UNICEF), the World Health Organization and the World Bank, 2024. Licence: CC BY-NC-SA 3.0 IGO;Metadata; SDG 2.2.2b)

nfsdata@who.int

Department of Nutrition and Food Safety

Survey estimates come with levels of uncertainty due to both sampling error and non-sampling error (e.g., measurement technical error, recording error etc.,). None of the two sources of errors have been fully considered for deriving estimates neither at country nor at regional or worldwide levels. Surveys are carried out in a specific period of the year, usually over a few months. However, this indicator can be affected by seasonality, factors related to food availability (e.g., pre-harvest periods), disease (e.g., rainy season and diarrhoea, malaria, etc.), and natural disasters and conflicts.