Shigella hits Homeless in New Mexico
Bernalillo County is experiencing an ongoing outbreak of Shigella flexneri. Since 2021, there have been over 300 cases, the majority among people experiencing homelessness. Laboratory testing has shown that the outbreak strain carries genomic patterns conferring resistance to fluoroquinolones, a class of antibiotics commonly used to treat Shigella infections. This strain of Shigella is part of a prolonged outbreak in New Mexico.
Shigellosis is characterized by diarrhea, sometimes with fever, malaise, nausea, vomiting and cramps. Stools typically contain blood and mucus, although mild infections consisting only of watery diarrhea may also occur. Illness is usually self-limited, lasting an average of 4-7 days although severe infections may occur in young children, the elderly, and in persons with poor nutritional status. Outbreaks commonly occur in conditions of crowding or poor sanitation.
Shigella is found in the stool (feces) of infected people and infected people can continue to shed Shigella bacilli for up to four weeks after symptoms have resolved. People become infected by direct or indirect fecal-oral transmission from an infected person, via:
- Person to person contact
- Contact with a contaminated object
- Eating food or drinking liquids prepared by infected food handlers
- Sexual contact
Recommendations for Clinicians:
Antimicrobial therapy is effective for shortening the duration of diarrhea and eradicating the organism from feces. Given the observed drug resistance to floroquinolones in this outbreak, clinicians prescribing antimicrobials may consider empirically treating with Azithromycin. Treatment should be used in patients with severe symptoms. For patients with mild illness, treatment may be indicated to prevent the spread of the organism and should be considered for patients experiencing homelessness or residing in congregant settings. Antimicrobial therapy should be administered for five days. Use of anti-motility or antidiarrheal medications are discouraged in adults. For prolonged or recurrent infections, providers should perform antimicrobial susceptibility testing to ensure appropriate treatment for patients with Shigella infection.
