Shigella - Shigellosis

Shigella Outbreak in San Diego County is Officially Over

With no new cases in more than a month, the Shigella outbreak (Shigellosis) declared in October 2021 among persons experiencing homelessness (PEH) in San Diego County is over.

The first identified case of Shigella was on October 7, 2021, and the last case Shigella case connected to the outbreak identified was December. 11, 2021. On January 14, 2022, the County sent a letter to City of San Diego officials informing them that the current outbreak of shigellosis is now considered closed. The County will continue to closely monitor case counts.

To learn more about the Shigella outbreak, visit the County News Center.

Outbreak Summary Update

Epidemiology

In total, there were 53 outbreak-related cases (47 confirmed, 6 probable). All cases experienced homelessness. There have been no deaths. Ages ranged from 19 – 70 years. Exposure periods ranged from August 11th to December 14th. The most recent symptom onset date is December 15th. Forty-four (44) cases reported substance use, 38 are known to use methamphetamine.

Descriptive Characteristics of Shigella Outbreak Cases (N=53)
Updated January 19, 2022

Characteristics	Total (N=53)
	Freq (%)
Gender
Male	32 (60.4)
Female	19 (35.8)
Transgender Female	2 (3.8)
Age Group
<18	0 (0)
18-44	24 (45.3)
45-64	25 (47.2)
≥65	4 (7.5)
Race and Ethnicity
American Indian/ Alaskan Native	0 (0)
Asian	0 (0)
Black, non-Hispanic/Latino	15 (28.3)
Hispanic/Latino	11 (20.7)
Native Hawaiian/Pacific Islander	0 (0)
White, non-Hispanic/Latino	26 (49.1)
Other	1 (1.9)
Hospitalizations	36 (67.9)
Sexual Orientation
Heterosexual	21 (39.6)
MSM	2 (3.8)
Declined to Answer	2 (3.8)
Unknown	28 (52.8)
Substance Use
Yes	44 (83)
No	2 (3.8)
Unknown	6 (11.2)

Figure 1. Epidemiological curve

Note: Website is updated as needed.

Important Information

Shigella (shih-GEHL-uh) is a bacterium that causes a disease called shigellosis. Children younger than 5 years are most likely to get shigellosis, but people from all age groups can get this disease. Most people with shigellosis will get better within 5 to 7 days without medical treatment. However, Shigella bacteria can cause more severe illness in infants, the elderly, or people with immune systems weakened by cancer, cancer treatments, or other serious conditions (like diabetes, kidney failure, liver disease, and HIV/AIDS).

Symptoms
Transmission
Prevention
Diagnosis
Treatment

Symptoms

People who come in contact with Shigella usually start experiencing symptoms 1 to 2 days after the contact with the bacteria. Symptoms of shigellosis may include:

Diarrhea (sometimes bloody)
Fever
Stomach pain
Feeling the need to pass stool (poop) even when the bowels are empty

Most people with shigellosis will get better within 5 to 7 days without medical treatment. However, Shigella bacteria can cause more severe illness in infants, the elderly, or people with immune systems weakened by cancer, cancer treatments, or other serious conditions (like diabetes, kidney failure, liver disease, and HIV/AIDS).

Transmission

People usually get sick from Shigella bacteria after putting something in their mouth or swallowing something that has come into contact with the stool (poop) of someone else who is sick with shigellosis. Just a small amount of Shigella bacteria can make someone sick.

People can get sick by:

Getting Shigella bacteria on their hands, which may happen after:
- Changing diapers of children who are infected with the germ
- Touching people who are sick who might have the germ on their hands or bodies
Eating food that was prepared by someone who is sick with the germ
Swallowing recreational water (for example, lake or river water) while swimming or drink water that was contaminated with stool containing the germ
Having exposure to stool during sexual contact with someone who is sick

Prevention

Shigella bacteria can spread very easily from person to person, so the best thing to do to keep from getting sick is to wash your hands with soap and water—especially after using the bathroom, after changing a child’s diapers, and before preparing food and eating.

If soap and water are not available, use an alcohol-based hand sanitizer with at least 60% alcohol (check the product label to be sure). Hand sanitizer with at least 60% alcohol is effective in killing Shigella bacteria. But use soap and water as soon as possible afterwards because hand sanitizer does not kill all types of germs and may not work as well if hands are visibly greasy or dirty.

Diagnosis

Many kinds of germs (e.g., bacteria, viruses, parasites) can cause diarrhea. Knowing which germ is causing an illness is important to help guide appropriate treatment. Healthcare providers can order laboratory tests to identify Shigella bacteria in the stool of an infected person.

Treatment

People who have shigellosis usually get better without antibiotic treatment in 5 to 7 days. People with mild shigellosis may need only fluids and rest. Bismuth subsalicylate (for example, Pepto-Bismol) may be helpful, but people sick with shigellosis should not use medications that slow down the way our body digests food, such as loperamide (for example, Imodium) or diphenoxylate with atropine (for example, Lomotil).

Healthcare providers may prescribe antibiotics to people with severe cases of shigellosis to help them get better faster. However, some antibiotics are not effective against certain types of Shigella. Healthcare providers can order laboratory tests to determine which antibiotics are likely to work. Tell your healthcare provider if you do not get better within a couple of days after starting antibiotics. They can do more tests to learn whether your type of Shigella bacteria can be treated effectively with the antibiotic you are taking. If not, your doctor may prescribe another antibiotic.