#15,802
In March of 2018, in mBio: The Gathering Storm: Is Untreatable Typhoid Fever on the Way?, we looked at the first large outbreak of extensively drug-resistant (XDR) typhoid - which emerged in the Sindh region of Pakistan (includes Karachi & Hyderabad) in late 2016.
In March of 2018, in mBio: The Gathering Storm: Is Untreatable Typhoid Fever on the Way?, we looked at the first large outbreak of extensively drug-resistant (XDR) typhoid - which emerged in the Sindh region of Pakistan (includes Karachi & Hyderabad) in late 2016.
Salmonella Typhi, the causative agent of Typhoid Fever, is a bacterium that has no known natural reservoir outside of humans. It is usually acquired via the fecal-oral route, often by consuming food or drink that has been handled by someone who is shedding the Salmonella Typhi bacteria.In 2018, the CDC issued a Level 2 travel advisory (now lowered to Level 1) for Extensively Drug-Resistant Typhoid in Pakistan (excerpts below).
Extensively Drug-Resistant Typhoid Fever in Pakistan
Warning - Level 3, Avoid Nonessential Travel
Alert - Level 2, Practice Enhanced Precautions
Watch - Level 1, Practice Usual Precautions
Key Points
- There is an ongoing outbreak of extensively drug-resistant (XDR) typhoid fever in Pakistan that does not respond to most antibiotics.
- During 2018, cases have been reported in the United Kingdom and in the United States among travelers returning from Pakistan.
- All travelers to Pakistan are at risk of getting XDR typhoid fever. Those who are visiting friends or relatives are at higher risk than are tourists and business travelers.
- Travelers to South Asia, including Pakistan, should take precautions to protect themselves from typhoid fever, including getting a typhoid fever vaccination.
- Travelers to these areas should also take extra care to follow safe food and water guidelines.
And nearly two years ago, in a COCA Call (see Extensively Drug-resistant Salmonella Typhi Infections Emerge Among Travelers to or from Pakistan) the CDC provided clinicians with information on diagnosing and treating travelers returning with the infection.
Since then, we've revisited the issue a few times, including ECDC: Increase Of Imported XDR-Typhoid Fever In Travelers From Pakistan and Taiwan CDC Reports 1st (imported) Case Of XDR-Typhoid, both serving as reminders that antibiotic resistance continues to increase around the globe, and poses a very real threat everywhere.
Yesterday, in light of limited, but continued importation and spread of XDR Salmonella Typhi among U.S. residents, the CDC released a new HAN (Health Alert Network) Advisory
Extensively Drug-Resistant Salmonella Typhi Infections Among U.S. Residents Without International Travel
Distributed via the CDC Health Alert Network
February 12, 2021, 1:00 PM ET
CDCHAN-00439
Summary
The Centers for Disease Control and Prevention (CDC) is providing—
- Information on extensively drug-resistant (XDR) Salmonella Typhi (Typhi) infections among U.S. residents without international travel,
- and Treatment recommendations for XDR Typhi infection.
Background
Typhoid fever is a systemic illness caused by the bacterium Salmonella enterica serotype Typhi (Typhi). Most people in the United States diagnosed with typhoid fever acquired it during international travel, but some acquired it in the United States. The disease is treated with antibiotics; without appropriate antibiotic treatment,12–30% of people with typhoid fever will die.
Typhi is transmitted through contaminated food and water and person-to-person contact. CDC recommends vaccination for people traveling to places where typhoid fever is common. Because typhoid fever vaccines are not 100% effective, travelers should always practice safe eating and drinking habits to help prevent infection.
In 2016, a large outbreak of extensively drug-resistant (XDR) Typhi infections began in Sindh province, Pakistan [1]. XDR Typhi strains are resistant to antibiotics generally recommended to treat typhoid fever, including ampicillin, ceftriaxone, chloramphenicol, ciprofloxacin, and trimethoprim-sulfamethoxazole. Isolates from patients linked to the outbreak in Pakistan are susceptible to carbapenems and azithromycin. Infections among travelers to or from Pakistan have been reported globally, including in the United States.
As of January 14, 2021, CDC has received 71 reports of XDR Typhi infection in the United States, with specimens obtained from February 9, 2018, through November 16, 2020. Among 67 patients with known travel history, 58 (87%) had traveled to Pakistan in the 30 days before illness began (Figure).
Nine (13%) patients from six states (NY [3], CA [2], IL, MD, NJ, and TX) reported that they had not traveled to Pakistan or any other country. Specimens from these nine patients were obtained from November 7, 2019, through October 7, 2020, with eight obtained in 2020. Susceptibility testing of these specimens showed the same resistance pattern described in Pakistan. CDC has not identified linkages among these patients or a common source of infection.
Case reporting of U.S. Typhi infections for 2020 is not yet complete. To date, 17 states have reported Typhi cases for 2020 compared with 39 states for 2019. Among 11 patients without international travel in 2020, eight patients were infected with XDR Typhi, one patient was infected with non-XDR Typhi, and susceptibility testing is pending for two others.
Before the outbreak in Pakistan, no case of ceftriaxone-resistant Typhi infection had been identified in the United States [2]. An unrelated cluster of ceftriaxone-resistant Typhi infections linked to Iraq has been reported in the United States and the United Kingdom [2].
Clinicians should consider empiric treatment with a carbapenem, azithromycin, or both agents for suspected typhoid fever in patients who did not travel out of the United States and for those who traveled to Pakistan or Iraq. Ceftriaxone remains an appropriate empiric treatment option for patients who traveled to countries other than Pakistan and Iraq.Clinicians should adjust treatment based on results of susceptibility testing.
This investigation is ongoing.
Recommendations for Clinicians
(Continue . . . )
While curbs on international travel during 2020 due to COVID-19 have likely slowed its spread, five years into this crisis, it has not gone away.
Another reminder - as if we needed one - that in our increasingly mobile society, even rare infectious diseases can spread quickly from anywhere in the world.
