Salmonella Weltevreden

Background: Salmonella enterica subsp. enterica serovar Weltevreden (antigenic formula 3,{10}{15}:r:z₆) is a serovar of the O:3,10 (E₁) serogroup.

NCBI PD link for serovar Weltevreden: https://www.ncbi.nlm.nih.gov/pathogens/isolates/#(taxgroup_name:%22Salmonella%20enterica%22)%20AND%20computed_types:(%22serotype=Weltevreden%22)

Genetic characteristics: A clonal group of serovar Weltevreden isolated in farmed shrimp from Vietnam’s Mekong Delta showed susceptibility to most tested antimicrobials, though some isolates exhibited resistance to florfenicol, chloramphenicol, sulfamethoxazole, or trimethoprim.

Animal reservoir: Wild geckos are likely to be the reservoir for serovar Weltevreden. Serovar Weltevreden was also frequently reported from seafood. 

Geographical distribution: Serovar Weltevreden has been found worldwide. Over the past 20 years, Salmonella Weltevreden has become a predominant serovar, particularly in Southeast Asia, including countries such as Oman, Singapore, China, Thailand, Vietnam, and India.

Human outbreaks: 

¹ Multiple serovars including Salmonella I 4,[5],12:b:-, Heidelberg, Javiana, Okatie, Weltevreden, and Thompson were involved in this outbreak. The case number here does not reflect the number of infections linked to Salmonella Weltevreden only.

² Sixty-five individuals across 11 states were reported infected with outbreak strains, including 64 cases of Salmonella Paratyphi B variant L(+) tartrate(+) and 1 case of Salmonella Weltevreden. 

Border rejections: There have been no recent border rejections linked to this serovar. 

Recalls: 

¹ Multiple Salmonella serovars including Salmonella Javiana, Mgulani and Weltevreden were found. AH USA Group Inc. issued a recall of its Black Fungus (Nam Meo) product.

² This recall was caused by a multistate outbreak described above. Avanti Frozen Foods of India expanded its voluntary recall of frozen cooked shrimp on August 13, 2021. The expansion now includes products imported into US from November 2020 through May 2021.

³ This recall was caused by a multistate outbreak described above. Core Ingredients issued a recall for eight frozen pre-prepared meals with best-before dates ranging from March 5, 2020, to October 4, 2020.

⁴ This recall was caused by a multi-country outbreak described above.

Relevant links:

1. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0134252
2. https://onlinelibrary.wiley.com/doi/abs/10.1111/zph.12873
3. https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2020.01985/full
4. https://pmc.ncbi.nlm.nih.gov/articles/PMC9927414/
5. https://www.liebertpub.com/doi/10.1089/fpd.2023.0064#:~:text=In%20the%20last%20two%20decades,et%20al.%2C%202021).
6. https://archive.cdc.gov/www_cdc_gov/salmonella/weltevreden-06-21/index.html
7. https://archive.cdc.gov/www_cdc_gov/salmonella/paratyphi-b-05-15/index.html
8. https://pmc.ncbi.nlm.nih.gov/articles/PMC10961741/
9. https://www.foodsafetynews.com/2019/10/almost-50-ill-in-australian-salmonella-outbreak/
10. https://pmc.ncbi.nlm.nih.gov/articles/PMC8242109/
11. https://pmc.ncbi.nlm.nih.gov/articles/PMC4418162/
12. https://www.eurosurveillance.org/content/10.2807/ese.13.32.18949-en
13. https://www.eurosurveillance.org/content/10.2807/esw.12.48.03321-en
14. https://webgate.ec.europa.eu/rasff-window/screen/notification/688257
15. https://www.foodsafetynews.com/2023/05/black-fungus-recalled-in-12-states-after-testing-finds-multiple-strains-of-salmonella/
16. https://webgate.ec.europa.eu/rasff-window/screen/notification/597121
17. https://www.fda.gov/food/outbreaks-foodborne-illness/outbreak-investigation-salmonella-weltevreden-frozen-pre-cooked-shrimp-april-2021#:~:text=CDC%20declares%20outbreak%20over.&text=The%20FDA%2C%20along%20with%20CDC,that%20the%20outbreak%20is%20over.
18. https://www.eurosurveillance.org/content/10.2807/esw.12.48.03321-en