Asian Journal of Biotechnology and Bioresource Technology

Typhoid fever is caused by bacterium called Salmonella enterica serovar typhi (often referred to as S. typhi). It has become rare developed countries, but remains an important cause of enteric disease in developing countries, resulting in an estimated 216,000 – 600,000 deaths per year, predominantly in children. Humans are the only source of infection of typhoid fever and transmission of S. typhi is by the fecal-oral route through contaminated water or food, prevention measures need to include water and sanitation improvements, as well as health education. Typhoid fever can be effectively treated with antibiotics, but growing rates of antibiotic resistance in many regions are making this treatment more difficult and costly. Given these facts, it seems necessary to consider a comprehensive approach to prevention of this disease that combines targeted vaccination as a short- to medium-term measure, combined with the long-term solutions of water and sanitation improvements and elevated living standards. To combat and to reduce the morbidity and mortality caused by typhoid fever, many preventive measures and strategies have been employed, the most important being vaccination. In recent years, many Salmonella vaccines have been developed including live attenuated as well as DNA vaccines and their clinical trials have shown encouraging results. However, with the increase in antibiotic resistance, the development of potent vaccine candidate for typhoid fever is needed.