Editing Typhoid fever (section)

== Prevention ==
[[File:Typhoid inoculation2.jpg|thumb|upright=1.3|Doctor administering a typhoid [[vaccination]] at a school in [[San Augustine County, Texas]], 1943]]

Sanitation and hygiene are important to prevent typhoid. It can spread only in environments where human feces can come into contact with food or drinking water. Careful food preparation and washing of hands are crucial to prevent typhoid. Industrialization contributed greatly to the elimination of typhoid fever, as it eliminated the public health hazards associated with having horse manure in public streets, which led to a large number of flies,<ref>{{cite web|url=http://www.historic-uk.com/HistoryUK/HistoryofBritain/Great-Horse-Manure-Crisis-of-1894/|title=The Great Horse Manure Crisis of 1894|url-status=live|archive-url=https://web.archive.org/web/20150525202107/http://www.historic-uk.com/HistoryUK/HistoryofBritain/Great-Horse-Manure-Crisis-of-1894/|archive-date=2015-05-25}}</ref> which are [[vector (epidemiology)|vectors]] of many pathogens, including ''Salmonella'' spp.<ref>{{cite journal | vauthors = Cirillo VJ | s2cid = 41428479 | title = "Winged sponges": houseflies as carriers of typhoid fever in 19th- and early 20th-century military camps | journal = Perspectives in Biology and Medicine | volume = 49 | issue = 1 | pages = 52–63 | date = 2006 | pmid = 16489276 | doi = 10.1353/pbm.2006.0005 }}</ref> According to statistics from the U.S. [[Centers for Disease Control and Prevention]], the [[Water chlorination|chlorination]] of drinking water has led to dramatic decreases in the transmission of typhoid fever.<ref>{{Cite web|url=https://www.cdc.gov/healthywater/drinking/history.html|title=History of Drinking Water Treatment {{!}} Drinking Water {{!}} Healthy Water {{!}} CDC|date=2018-10-10|website=www.cdc.gov|language=en-us|access-date=2020-04-21}}</ref>

===Vaccination===
Two [[typhoid vaccine]]s are licensed for use in the prevention of typhoid:<ref name=Mil2018/> the live, oral [[Ty21a]] vaccine (sold as Vivotif by [[Crucell]] Switzerland AG) and the injectable [[typhoid polysaccharide vaccine]] (sold as Typhim Vi by [[Sanofi Pasteur]] and Typherix by [[GlaxoSmithKline]]). Both are efficacious and recommended for travelers to areas where typhoid is endemic. Boosters are recommended every five years for the oral vaccine and every two years for the injectable form.<ref name="Mil2018"/> An older, killed [[whole-cell vaccine]] is still used in countries where the newer preparations are not available, but this vaccine is no longer recommended for use because it has more side effects (mainly pain and inflammation at the site of the injection).<ref>{{cite journal | vauthors = Marathe SA, Lahiri A, Negi VD, Chakravortty D | title = Typhoid fever & vaccine development: a partially answered question | journal = The Indian Journal of Medical Research | volume = 135 | issue = 2 | pages = 161–9 | date = 2012 | pmid = 22446857 | pmc = 3336846 }}</ref>
[[File:Vivotif-typhoid-live-oral-vaccine.JPG|thumbtime=1:00|thumb|Vivotif – oral typhoid vaccine of live-attenuated ''S. enterica'' Typhi strain Ty21a]]
To help decrease rates of typhoid fever in [[developing nation]]s, the [[World Health Organization]] (WHO) endorsed the use of a vaccination program starting in 1999. Vaccination has proven effective at controlling outbreaks in high-incidence areas and is also very cost-effective: prices are normally less than US$1 per dose. Because the price is low, poverty-stricken communities are more willing to take advantage of the vaccinations.<ref name=":0">{{cite journal | vauthors = Date KA, Bentsi-Enchill A, Marks F, Fox K | title = Typhoid fever vaccination strategies | journal = Vaccine | volume = 33 | pages = C55-61 | date = June 2015 | issue = Suppl 3 | pmid = 25902360 | doi = 10.1016/j.vaccine.2015.04.028 | pmc = 10644681 }}</ref> Although vaccination programs for typhoid have proven effective, they alone cannot eliminate typhoid fever.<ref name=":0" /> Combining vaccines with public health efforts is the only proven way to control this disease.<ref name=":0" />

Since the 1990s, the WHO has recommended two typhoid fever vaccines. The ViPS vaccine is given by injection and the Ty21a by capsules. Only people over age two are recommended to be vaccinated with the ViPS vaccine, and it requires a revaccination after 2–3 years, with a 55–72% efficacy. The Ty21a vaccine is recommended for people five and older, lasting 5–7 years with 51–67% efficacy. The two vaccines have proved safe and effective for epidemic disease control in multiple regions.<ref name=":0"/>

A version of the vaccine combined with a [[hepatitis A]] vaccine is also available.<ref>{{cite web |title=Vivaxim Solution for injection |url= http://www.nps.org.au/medicines/immune-system/vaccines-and-immunisation/for-individuals/brands/vivaxim-solution-for-injection |website=NPS MedicineWise |access-date=10 April 2017 |url-status=dead |archive-url=https://web.archive.org/web/20151001161831/http://www.nps.org.au/medicines/immune-system/vaccines-and-immunisation/for-individuals/brands/vivaxim-solution-for-injection |archive-date=1 October 2015}}</ref>

Results of a phase 3 trial of typhoid [[conjugate vaccine]] (TCV) in December 2019 reported 81% fewer cases among children.<ref>{{cite news | vauthors = Gallagher J |title=Typhoid vaccine 'works fantastically well' |work=BBC News |url=https://www.bbc.com/news/health-50587608?linkId=80686859 |access-date=17 January 2020 |date=4 December 2019}}</ref><ref>{{cite journal | vauthors = Shakya M, Colin-Jones R, Theiss-Nyland K, Voysey M, Pant D, Smith N, Liu X, Tonks S, Mazur O, Farooq YG, Clarke J, Hill J, Adhikari A, Dongol S, Karkey A, Bajracharya B, Kelly S, Gurung M, Baker S, Neuzil KM, Shrestha S, Basnyat B, Pollard AJ | title = Phase 3 Efficacy Analysis of a Typhoid Conjugate Vaccine Trial in Nepal | journal = The New England Journal of Medicine | volume = 381 | issue = 23 | pages = 2209–2218 | date = December 2019 | pmid = 31800986 | pmc = 6785806 | doi = 10.1056/NEJMoa1905047 | doi-access = free }}</ref>