Bacterial and Viral infections affect all ages and are the leading cause of morbidity and mortality across the world. Viruses are probably the most common cause of infectious disease acquired within indoor environments and both virus and bacteria have considerable impact on human health, ranging from severe life-threatening illnesses to relatively mild and self-limiting or asymptomatic diseases. This may depend on the immune status of the patient and their ability to clear infection as well as the characteristics of the pathogen. Increasing numbers of people who have reduced immunity to infection, where the consequences of infection can be much more serious than healthy individuals. In general, bacteria and viruses causing respiratory and gastrointestinal diseases spread rapidly in the community and cause considerable morbidity.

Despite the advances in medical and science technology, there are few conventional medications or vaccines for most of the infection causing bacteria and viruses. However, the microorganisms gaining resistance to the existing drugs which is making the treatment difficult. Because of this, most of the researchers are focusing on nutritional supplements for natural immune boosting. A healthy immune system prevents the incidence of various infectious diseases. There are numerous vitamins and trace elements which are essential for normal functioning of the immune system. Additionally, several herbals, probiotics and micronutrients also have shown potency for treatment and prevention of infections. Moreover, several nutraceuticals and probiotics have also shown a complementary role in enhancing immune responses. Therefore, the purpose of study is to investigate the effect of nutraceuticals as an immune booster for maintaining a healthy immune system in adult population.