Editing Typhoid fever (section)

=== Resistance ===
As [[Antimicrobial resistance|resistance]] to ampicillin, chloramphenicol, trimethoprim-sulfamethoxazole, and [[streptomycin]] is now common, these agents are no longer used as first-line treatment of typhoid fever.<ref>{{Cite web|url=https://wwwnc.cdc.gov/travel/notices/watch/xdr-typhoid-fever-pakistan|title=Extensively Drug-Resistant Typhoid Fever in Pakistan – Watch – Level 1, Practice Usual Precautions – Travel Health Notices {{!}} Travelers' Health {{!}} CDC|website=wwwnc.cdc.gov|access-date=2020-04-21}}</ref> Typhoid resistant to these agents is known as multidrug-resistant typhoid.<ref>{{cite journal | vauthors = Zaki SA, Karande S | title = Multidrug-resistant typhoid fever: a review | journal = Journal of Infection in Developing Countries | volume = 5 | issue = 05 | pages = 324–37 | date = May 2011 | pmid = 21628808 | doi = 10.3855/jidc.1405 | doi-access = free }}</ref>

Ciprofloxacin resistance is an increasing problem, especially in the [[Indian subcontinent]] and [[Southeast Asia]]. Many centres are shifting from ciprofloxacin to [[ceftriaxone]] as the first line for treating suspected typhoid originating in South America, India, Pakistan, Bangladesh, Thailand, or Vietnam. Also, it has been suggested that [[azithromycin]] is better at treating resistant typhoid than both fluoroquinolone drugs and ceftriaxone.<ref name="pmid21975746" /> Azithromycin can be taken by mouth and is less expensive than ceftriaxone, which is given by injection.<ref>{{cite journal | vauthors = Gibani MM, Britto C, Pollard AJ | title = Typhoid and paratyphoid fever: a call to action | journal = Current Opinion in Infectious Diseases | volume = 31 | issue = 5 | pages = 440–448 | date = October 2018 | pmid = 30138141 | pmc = 6319573 | doi = 10.1097/QCO.0000000000000479 }}</ref>

A separate problem exists with laboratory testing for reduced susceptibility to ciprofloxacin; current recommendations are that isolates should be tested simultaneously against ciprofloxacin (CIP) and against [[nalidixic acid]] (NAL), that isolates sensitive to both CIP and NAL should be reported as "sensitive to ciprofloxacin", and that isolates sensitive to CIP but not to NAL should be reported as "reduced sensitivity to ciprofloxacin". But an analysis of 271 isolates found that around 18% of isolates with reduced susceptibility to [[fluoroquinolones]], the class to which CIP belongs ([[Minimum inhibitory concentration|MIC]] 0.125–1.0&nbsp;mg/L), would not be detected by this method.<ref>{{cite journal | vauthors = Cooke FJ, Wain J, Threlfall EJ | title = Fluoroquinolone resistance in Salmonella Typhi | journal = BMJ | volume = 333 | issue = 7563 | pages = 353–4 | date = August 2006 | pmid = 16902221 | pmc = 1539082 | doi = 10.1136/bmj.333.7563.353-b }}</ref>