The major causes for this is poverty, world conflicts lack of education, natural disaster and poor access to health care. PCM usually manifest early in children between 6 month and 2 years of age and is associated with early Weanury, delayed introduction of education of complementary foods, a low-protein diet and serve or frequent infections [Kwena et al., 2003).
Nearly one tend of children in the developing world are malnourished [Ahmed, T.; et al., 2009].
Diverse studies have demonstrated that malnutrition increases the risks of infection and death[Pelletier, D. 1994],
[Pelletier, D.; and Frogillo, EA.2003].
The most frequent causes of death in children under 5 years old are acute diarrhea and acute respiratory infection. Several studies have shown that malnutrition is frequently casually associated with these death [Pelletier, D. et al.,1993]. However, as impacts is largely underestimated.
Several studies have been conducted to examine associations among malnutrition deficiencies in cell mediated immunity, and the incidences respiratory infection children under 5 years of age in 2001, the world health organization (WHO) established the external child Health Epidemiology group References group (CHERG) to develop estimates of the proportion of deaths in children younger than age 5 years attributable to pneumonia, diarrhea, malarial and measles of the of estimated 8,775 million deaths in children younger than 5 years worldwide in 2008, infections diseases caused 68% (5,970 million), with the largest percentage due to pneumonia (18%), diarrhea (15%), and malaria (8%) [Black,R. E.; et al., 2010]. A separate study reported different risk estimates, with stronger association between nutritional status and mortality and acute respiratory infections that coincide with malnutrition [Yoon, P. W.; et al., 1997].
The relationship between nutritional status and the immune system has been a topic of study for decades. Several studies have demonstrated that PCM impairs host immune responses, including cell mediated immunity [Srcrimshew, N. S.; et al., 1997] and secretory IgA production [Reddy, v ; et al.,1976] [Ha, CL; woodward, B. 1997]. PCM is a major cause of secondary immune deficiency in the world.