S. Havana¶

At a Glance


Antigenic Formula	`1,13,23:f,g,[s]:-`
Serogroup	O:13 (G)
NCBI Pathogen Detection	View isolates

Background Information¶

Salmonella enterica subsp. enterica serotype Havana (antigenic formula: 1,13,23:f,g,[s]:-) is a serovar of the O:13 (G) serogroup. Serovar Havana was first identified in 1937 after being isolated from spinal fluid during a meningitis outbreak at a hospital in Havana, Cuba, which led to the deaths of 21 newborns.

Genetic Characteristics¶

Serovar Havana has been found to be polyphyletic with seven lineages identified. The strain (Havana ST1524) exhibited high virulence in the Galleria mellonella larvae infection model. Additionally, this strain was identified as carrying the mcr-9.1 gene, which, when cloned, confers a significant 16-fold increase in colistin resistance. The outbreak strains originating in pediatric wards of two hospitals in Shiraz, Iran demonstrated high resistance to chloramphenicol, tetracycline, gentamicin, ampicillin, kanamycin, and cephalothin except trimethoprim-sulfamethoxazole. Among them, only 14 (32%) were susceptible to cephalothin, and 6 (14%) to gentamicin, with minimal inhibitory concentrations of 1.6 µg/mL and >3.1 µg/mL, respectively.

Animal Reservoir¶

Chicken might be a potential reservoir of serovar Havana. It has also been found in sea lions, cattle, horses, and swine.

Geographical Distribution¶

Serovar Havana has been reported worldwide but mainly in Europe and the US.

Human/Animal Outbreaks¶

There are multiple human outbreaks associated with serovar Havana. Here are some examples:

Year	Location	Associated source	Number of cases
2019	Canada	Tahini and halva from Syria	2
2018	Australia	Alfalfa sprouts	31
1998	US: CA & AZ	Alfalfa sprouts	18
1987	US: GA	Chicken	73

Border Rejections¶

Multiple border rejections linked to serovar Havana have been reported. Here are some examples:

Year	Exporting country	Importing country	Associated source	Product category
2021	Italy	Switzerland	Soybean meal¹	Feed materials
2021	Germany	Austria	Linseed meal extracted with soapstock	Feed materials
2020	Poland	Czech Republic	Chilled chicken legs	Poultry meat and poultry meat products

¹ Heat treatment was further implemented.

Recalls¶

Multiple recalls linked to serovar Havana have been reported. Here are some examples:

Year	Location	Recalled food	Type
2025	Norway	Alfalfa seeds from Italy	Nuts, nut products and seeds
2024	Germany	Helva with pistachios from Türkiye	Nuts, nut products and seeds
2023	Italy	Farina di pesce from Estonia	Feed materials
2021	US	Hummus	Prepared dishes and snacks