A dozen countries, including the United States, have reported more than 250 Shigella infections in people who went to Cape Verde.

An increase in shigellosis cases, mainly caused by Shigella sonnei, among travelers returning from Cape Verde, also known as Cabo Verde, has been reported in Europe, the United Kingdom, and the United States since September 2022.

Twelve countries have recorded 221 confirmed Shigella sonnei infections and 37 possible cases, all with a link to Cape Verde, which is in West Africa. The UK has the most cases with 95, followed by the Netherlands with 47, Sweden with 42, and France with 31. The United States has four patients.

Sequencing analysis of 106 human isolates from the Czech Republic, Netherlands, Sweden, UK, and the U.S. shows a genetically compact cluster suggesting a common source, said health officials.  

Of the U.S. cases, one person reported going to Cape Verde and the travel history for the other patients is unknown. Sick people include three females and one male aged from 3 to 88 years old. Collection dates ranged from Nov. 2, 2021, to Oct. 2, 2022.

Other pathogens recorded
Many ill people stayed in five-star all-inclusive hotels in the region of Santa Maria on the island of Sal. The most recent cases were in Sweden in mid-January 2023. Almost three times more women than men are affected. Two cases in Portugal were hospitalized.

Multiple modes of transmission are plausible, and the most likely way is through food, including via infected food handlers. However, person-to-person transmission is also possible, said the European Centre for Disease Control and Prevention (ECDC).

Shigella co-infections with other bacterial and parasitic pathogens such as Salmonella Mbandaka; Campylobacter; Cryptosporidium; and strains of E. coli have been reported among patients.

The Shigella sonnei strain in the outbreak shows resistance to trimethoprim and streptomycin but in some cases, multidrug resistance has been found. Detection of a resistance gene against hydrogen peroxide indicates Shigella sonnei isolates’ regular exposure to this disinfectant, said ECDC.

Holiday Claims Bureau and Hudgell Solicitors in the UK are representing people with confirmed Shigella infection and more than 500 people have asked lawyers at Irwin Mitchell to investigate illnesses linked to trips to Cape Verde.

ECDC and the European office of the World Health Organization (WHO) have been in contact with authorities in Cape Verde to support investigations on the sources of infection and to increase awareness among healthcare professionals in the country. Two meetings were held in January with officials from Cape Verde and the International Food Safety Authorities Network (INFOSAN) to discuss the epidemiological situation, based on cases notified in 2022.

About Shigella
Shigella bacteria cause an infection called shigellosis. Most infected people have diarrhea, fever, and stomach cramps. Symptoms usually begin a couple of days after infection and last a week.

Shigellosis is caught by oral contact with material contaminated by feces, either through direct person-to-person contact, via contaminated food or water, or via objects which have been in contact with feces. The dose needed for infection is small, usually microscopic. Food-related outbreaks are often caused by infected food handlers, who contaminate ready-to-eat items like salads.

Handwashing with soap and water is important, especially after using the toilet and before preparing or eating food. There is no vaccine to prevent Shigella infection. 

People with shigellosis should not attend school, handle food, or provide child or patient care whilst ill. People should stay at home for 48 hours after symptoms have ceased. 

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