Key points
- Non-infectious disease outbreaks and disease clusters can be caused by exposures to toxins, chemicals, or other substances found in the environment.
- CDC provides expertise in epidemiology and medical toxicology to investigate outbreaks domestically and internationally.
Overview
CDC provides subject matter expertise in epidemiology and medical toxicology to investigate outbreaks and disease clusters related to environmental exposures. These non-infectious disease outbreaks and disease clusters can be caused by exposures to:
- Toxins
- Chemicals
- Other substances found in the environment
Epidemiology is the study of the distribution and causes of diseases and other health outcomes in populations. Medical toxicology is the field of medicine that focuses on the diagnosis, management, and prevention of poisoning and other adverse health effects caused by:
- Medications
- Occupational and environmental toxins
- Radiation
- Biological agents
How outbreaks are investigated
When outbreaks and disease clusters related to environmental exposures occur, epidemiologists and medical toxicologists from CDC work with partners to:
- Determine the extent of the outbreak or cluster
- Describe the illness
- Identify the etiology (cause)
- Identify the source of exposure
Partners include federal, state, local, and international public health agencies.
To help answer questions, they collect different types of data, including:
- Epidemiologic data, such as who got sick, when, and where
- Clinical data, such as patient signs and symptoms
- Laboratory data, such as test results from biological specimens or environmental samples
CDC investigators also use poison center data to identify outbreaks and disease clusters related to emerging environmental hazards. For more information, see the National Chemical and Radiological Surveillance Program webpage.
Epidemiologic assistance
CDC can help investigate domestic and international outbreaks related to environmental exposures. CDC can help in different ways, including providing technical assistance or conducting an Epi-Aid.
Contact CDC outbreak response experts.
Outbreak and disease cluster investigation highlights
Unusual patterns of cancer and environmental concerns
CDC provides technical assistance and helps develop guidance for state, tribal, local, and territorial health departments on responding to concerns about unusual patterns of cancer and cancer clusters. A cancer cluster is defined as a greater than expected number of the same or etiologically-related cancer cases that occurs within a group of people in a geographic area over a specified period.
Did you know?
Health departments may request technical assistance in response to unusual patterns of cancer and cancer clusters from CDC.
Acute kidney injury among children likely associated with diethylene glycol–contaminated medications
In 2022, The Gambia’s Ministry of Health requested assistance from CDC to help investigate a large cluster of acute kidney injury (AKI) among young children. The investigation involved multiple international partners and personnel from across CDC. Together, they were able to characterize the illness, describe the epidemiology, and identify potential causes and their sources.
The investigation found that in 2022, 78 children were suspected to have AKI, and 66 died. Most patients (75%) were younger than two years of age. After conducting interviews and analyzing medication samples, investigators found that the cause of the illness was likely medications contaminated with diethylene glycol.
Acute nonviral hepatitis associated with a brand of alkaline water
In 2021, CDC, the U.S. Food and Drug Administration (FDA), the Nevada Department of Health and Human Services, and the Southern Nevada Health District investigated cases of acute nonviral hepatitis with an unknown cause in Nevada and surrounding states. Acute nonviral hepatitis is liver inflammation that occurs suddenly and can lead to liver failure. The investigation found 21 probable cases and four suspected cases of acute nonviral hepatitis linked to consuming "Real Water," a brand of alkaline water. Eighteen probable cases and four suspected cases were identified in Nevada, and three probable cases were identified in California.
Synthetic cannabinoids
CDC has responded to numerous outbreaks of illnesses related to synthetic cannabinoids. Synthetic cannabinoid products usually consist of various man-made chemicals. Reported side effects from these products are often severe and can include kidney failure, heart attack, and death.
Liver failure associated with dietary supplements
On September 9, 2013, the Hawaii Department of Health (HDOH) was notified by a hospital that it had observed seven patients with acute hepatitis and liver failure of unknown cause. All patients reported using a dietary supplement marketed for weight loss and muscle gain. As a result, HDOH requested assistance from CDC and the FDA to identify other illnesses, describe common clinical features, and characterize risk factors for illness. In all, investigators identified 92 cases of acute hepatitis of unknown cause.
Unidentified liver disease in Ethiopia
In 2007, the Ethiopia Ministry of Health and Ethiopia Health and Nutrition Research Institute asked CDC and other partners to help investigate an outbreak of an unidentified liver disease. After conducting an extensive investigation, the cause of the outbreak was found to be exposure to toxic pyrrolizidine alkaloids.