User:Yangthao/sandbox

Since the 1990s there has been 2 typhoid fever vaccines recommended by the World Health Organization. The ViPS vaccine is given via injection, while the Ty21a is taken through capsules. It is recommended only people 2 years or older be vaccinated with the ViPS vaccine and requires a revaccination after 2-3 years with a 55-72% vaccine efficacy. The alternative Ty21a vaccine is recommended for people 5 years or older, and has a 5-7-year duration with a 51-67% vaccine efficacy. The two different vaccines have been proven as a safe and effective treatment for epidemic disease control in multiple regions. Residents treated with the ViPS vaccine in Guangxi province within a 11-year time span has shown a reduced of incidence from 57/100,000 in 1995 to an incidence of <5/100,000 in 2006.