Since its most recent update on Oct. 18, the federal Centers for Disease Control and Prevention (CDC) has added more than 100 people to its patient count in a Salmonella outbreak linked to onions from Mexico.

There are now 808 confirmed patients in the outbreak, 156 more than the previous report from the CDC.  In addition to the 37 states where sick people live, Puerto Rico is now part of the outbreak, according to today’s agency update.

Of 505 patients with complete information available, 157 people have been so sick they had to be admitted to hospitals. That is higher than the usual hospitalization rate associated with Salmonella infections.

Multiple companies have recalled onions in relation to the outbreak. All recalled onions were supplied by ProSource Produce LLC in Idaho and Keeler Family Farms in New Mexico. They were imported from the state of Chihuahua, Mexico, between July 1 and Aug. 31.

There is concern that consumers and businesses may have the recalled onions on hand because of their long shelf life. The CDC reports that fresh onions can last up to three months or more when stored properly. Officials say to wash surfaces and containers these onions may have touched using hot soapy water or a dishwasher

Consumers and businesses are urged to throw away any onions that they cannot determine the country of origin for. The onions were sold in a variety of bag sizes and out of bulk bins.

The Food and Drug Administration  (FDA) is assisting with the outbreak investigation and posting onion recalls as they occur. Visit the FDA’s recall page to find out what onions have been recalled. Canada is also involved at this point, recalling onions under a variety of brand names. As of today no illnesses have been confirmed in Canada.

The most recent confirmed illness in the United States started on Oct. 13, with the first illness having been confirmed on May 31. Additional patients are expected by public health officials because of the long life shelf life of the onions and the time it takes to diagnose, confirm and report illnesses.

Sick people range in age from less than 1 year to 101 years, with a median age of 37, and 57 percent are female. 

Whole genome sequencing of bacteria from 709 people’s samples did not predict any antibiotic resistance. Five people’s samples were predicted to be resistant to one or more of the following antibiotics: amoxicillin-clavulanic acid, ampicillin, cefoxitin, and ceftriaxone, gentamicin, streptomycin, sulfamethoxazole, and tetracycline.

About Salmonella infections
Food that is contaminated with Salmonella bacteria usually does not look, smell or taste spoiled. Anyone can become sick with a Salmonella infection, but infants, children, seniors and people with weakened immune systems are at higher risk of serious illness because their immune systems are fragile, according to the CDC.

Anyone who has eaten any of the recalled onions or onions of unknown origin and developed symptoms of Salmonella infection should seek medical attention. Sick people should tell their doctors about the possible exposure to Salmonella bacteria because special tests are necessary to diagnose salmonellosis. Salmonella infection symptoms can mimic other illnesses, frequently leading to misdiagnosis.

Symptoms of Salmonella infection can include diarrhea, abdominal cramps, and fever within 12 to 72 hours after eating contaminated food. Otherwise healthy adults are usually sick for four to seven days. In some cases, however, diarrhea may be so severe that patients need to be hospitalized. 

Older adults, children, pregnant women and people with weakened immune systems, such as cancer patients, are more likely to develop a severe illness and serious, sometimes life-threatening conditions.

It is possible for some people to be infected with the bacteria and to not get sick or show any symptoms, but to still be able to spread the infection to others.

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