April 2021
Emerging Infectious Diseases Journal
Highlights: Emerging Infectious Diseases, Vol. 27, No. 4, April 2021
Important Note: Not all articles that EID publishes represent work done at CDC or by CDC staff. In your stories, please clarify whether a study was conducted by CDC (“a CDC study”) or by another institution (“a study published by CDC in the EID journal”). Opinions expressed by authors contributing to EID do not necessarily reflect the opinions of CDC or the institutions with which the authors are affiliated. EID requests that, when possible, you include a live link to the actual journal article in your stories. Once the embargo lifts, this month’s articles will be found in the Ahead of Print section of the EID website at https://wwwnc.cdc.gov/eid/ahead-of-print.
The articles of interest summarized below will appear in the April 2021 issue of Emerging Infectious Diseases, CDC’s monthly peer-reviewed public health journal. This issue will feature Emerging Viruses. The articles are embargoed until March 17, 2021, at 12 p.m. EDT.
1. Norovirus GIV Foodborne Outbreak, Wisconsin, USA, Leslie Barclay et al.
Norovirus is a very contagious virus that causes outbreaks of vomiting and diarrhea. Infection can be acquired by direct contact with an infected person, consuming contaminated food or water, hand to mouth after touching a contaminated surface, or being close to a person who vomits. Noroviruses are genetically divided into different genogroups which are further classified into strain types. All norovirus infections cause similar clinical symptoms and are transmitted in the same ways, regardless of their genogroup. In the United States, more than 99% of all norovirus outbreaks are caused by genogroups I and II. However, in May 2016, a norovirus outbreak in Wisconsin, traced to a fruit salad served at a restaurant, was linked to a novel genogroup IV virus. Outbreaks caused by genogroup IV viruses are rare, and the last one was reported in the United States in 2001. Detecting norovirus genogroup IV associated with contaminated food in this outbreak shows that this virus continues to circulate among people. Typically, during gastroenteritis outbreaks, norovirus testing is conducted for genogroups I and II only; additional testing for genogroup IV would help determine the cause of more outbreaks.
Contact: CDC Media Relations, phone: 404-639-3286 or email: media@cdc.gov
2. Sexual Contact as a Risk Factor for Campylobacter Infection, Katrin Gaardbo Kuhn et al.
In the United States, Campylobacter infection is the most common bacterial cause of diarrheal illness. Campylobacter is carried by animals such as poultry, wild birds, pets, and farm animals that show no signs of illness, and the bacteria are transmitted to people by unsafe handling or consuming raw or undercooked chicken, consuming raw milk, or contact with infected animals. Transmission to people can also occur when fruits and vegetables or drinking water supplies are contaminated by feces of infected animals. Although the resulting illness, campylobacteriosis, is primarily considered a foodborne illness, not all cases can be linked to food. High incidence of Campylobacter infection among men who have sex with men (MSM) led Danish researchers to explore the possibility of sexual contact as a risk factor. They conducted a case–control study from national surveillance data in Denmark, comparing the odds of MSM acquiring Campylobacter infection with that of acquiring Shigella infection (known to be spread by sexual transmission) and Salmonella infection (almost exclusively spread by foodborne transmission). Odds of Campylobacter and Shigella infections, but not Salmonella infections, were significantly higher among MSM than among controls, indicating that Campylobacter can be transmitted during sexual contact. Some bacterial pathogens, including Shigella, are known to be transmitted during sex and have been associated with high risk for infection among MSM because of anal–oral contact. The risk for infection through oral–anal sexual contact is likely to be equally relevant for heterosexual persons, and it is recommended that public health efforts to control Campylobacter be expanded to include consideration of this newly discovered transmission route.
Contact: April Sandefer, Director of Communications, University of Oklahoma OU Health, april.sandefer@oumedicine.com, phone: 405-271-6864
3. Blastomycosis Surveillance in 5 States, United States, 1987–2018, Kaitlin Benedict et al.
Blastomycosis is a fungal infection caused primarily by inhaling Blastomyces dermatitidis and B. gilchristii fungi that exist in the environment, primarily in moist soil and decomposing plant matter. It does not spread from person to person. The seriousness of infection can range from no symptoms at all to life-threatening illness involving acute respiratory distress syndrome or spread of the infection beyond the lungs. Many blastomycosis cases likely go undetected because the illness can clear up before a person sees a doctor for diagnosis and because doctors’ awareness of this relatively uncommon disease is low in most parts of the United States. Most blastomycosis cases in the United States are thought to occur in areas surrounding the Ohio and Mississippi River valleys, the Great Lakes, and the Saint Lawrence River, but the infection’s actual geographic range is broader than generally appreciated. Furthermore, the fungus is difficult to isolate from the environment, which makes investigating potential sources somewhat challenging. To better characterize this disease, researchers analyzed combined surveillance data from 5 states that require doctors and labs to report blastomycosis cases to their public health departments (Arkansas, Louisiana, Michigan, Minnesota, and Wisconsin). A review of their surveillance systems identified 4,441 cases reported during 1987–2018 (an average of 192 cases per year). The median age of patients was 46 years, 2,892 (65%) patients were male, 1,662 (57%) were hospitalized, and 278 (8%) died. The median time from symptom onset to diagnosis was 33 days. The severity of illness and diagnostic delays suggest that surveillance underestimates the actual number of cases. More in-depth surveillance in additional states could shed light on how and where blastomycosis occurs and inform efforts to increase awareness of the disease.
Contact: CDC Media Relations, phone: 404-639-3286 or email: media@cdc.gov
