Multiple lineages of monkeypox virus detected in the United States, 2021-2022.

Monkeypox is a viral zoonotic disease endemic in Central and West Africa. In May 2022, dozens of non-endemic countries reported hundreds of monkeypox cases, most with no epidemiological link to Africa. We identified two lineages of monkeypox virus (MPXV) among two 2021 and seven 2022 US monkeypox cases: the major 2022 outbreak variant called B.1 and a minor contemporaneously sampled variant called A.2. Analyses of mutations among these two variants revealed an extreme preference for GA-to-AA mutations indicative of human APOBEC3 cytosine deaminase activity among Clade IIb MPXV (previously West African, Nigeria) sampled since 2017. Such mutations were not enriched within other MPXV clades. These findings suggest that APOBEC3 editing may be a recurrent and a dominant driver of MPXV evolution within the current outbreak.

Foodborne Botulism Outbreak Associated With Commercial Nacho Cheese Sauce From a Gas Station Market.

BACKGROUND: Botulism is a rare and potentially fatal paralytic disease caused by botulinum neurotoxin (BoNT). In April 2017, 4 California residents from 2 adjacent counties were hospitalized with suspected foodborne botulism, precipitating an investigation by state and local public health departments in California. METHODS: We interviewed suspected botulism patients and their families, inspected the suspect establishment, and collected suspect food. We tested patient sera, stool, and gastric aspirates using mouse bioassay for BoNT and/or culture for Clostridium botulinum. We tested suspect food and environmental samples for BoNT and confirmed presumptive positives using direct mouse bioassay and culture. We performed whole-genome sequencing on food and clinical isolates. RESULTS: From April 2017 through May 2017, 10 patients in the Sacramento area were hospitalized with laboratory-confirmed botulism; 7 required mechanical ventilation, and 1 died. Of 9 patients with information, all had visited Gas Station X before illness onset, where 8 reported consuming a commercial cheese sauce. BoNT/A and/or BoNT/A-producing C. botulinum were detected from each patient and from leftover cheese sauce. Clostridium botulinum isolates from 4 patients were closely related to cheese sauce isolates by whole-genome high-quality single-nucleotide polymorphism analysis. No other botulism cases associated with this cheese sauce were reported elsewhere in the United States. CONCLUSIONS: This large foodborne botulism outbreak in California was caused by consumption of commercial cheese sauce dispensed at a gas station market. The epidemiologic and laboratory evidence confirmed the cheese sauce as the outbreak source. The cheese sauce was likely locally contaminated, although the mechanism is unclear.

Shiga Toxin-Producing Escherichia coli Infections Associated With Romaine Lettuce-United States, 2018.

BACKGROUND: Produce-associated outbreaks of Shiga toxin-producing Escherichia coli (STEC) were first identified in 1991. In April 2018, New Jersey and Pennsylvania officials reported a cluster of STEC O157 infections associated with multiple locations of a restaurant chain. The Centers for Disease Control and Prevention (CDC) queried PulseNet, the national laboratory network for foodborne disease surveillance, for additional cases and began a national investigation. METHODS: A case was defined as an infection between 13 March and 22 August 2018 with 1 of the 22 identified outbreak-associated E. coli O157:H7 or E. coli O61 pulsed-field gel electrophoresis pattern combinations, or with a strain STEC O157 that was closely related to the main outbreak strain by whole-genome sequencing. We conducted epidemiologic and traceback investigations to identify illness subclusters and common sources. A US Food and Drug Administration-led environmental assessment, which tested water, soil, manure, compost, and scat samples, was conducted to evaluate potential sources of STEC contamination. RESULTS: We identified 240 case-patients from 37 states; 104 were hospitalized, 28 developed hemolytic uremic syndrome, and 5 died. Of 179 people who were interviewed, 152 (85%) reported consuming romaine lettuce in the week before illness onset. Twenty subclusters were identified. Product traceback from subcluster restaurants identified numerous romaine lettuce distributors and growers; all lettuce originated from the Yuma growing region. Water samples collected from an irrigation canal in the region yielded the outbreak strain of STEC O157. CONCLUSIONS: We report on the largest multistate leafy greens-linked STEC O157 outbreak in several decades. The investigation highlights the complexities associated with investigating outbreaks involving widespread environmental contamination.

Emergence of Extensively Drug-Resistant Salmonella Typhi Infections Among Travelers to or from Pakistan - United States, 2016-2018.

In February 2018, a typhoid fever outbreak caused by Salmonella enterica serotype Typhi (Typhi), resistant to chloramphenicol, ampicillin, trimethoprim-sulfamethoxazole, fluoroquinolones, and third-generation cephalosporins, was reported in Pakistan. During November 2016-September 2017, 339 cases of this extensively drug-resistant (XDR) Typhi strain were reported in Pakistan, mostly in Karachi and Hyderabad; one travel-associated case was also reported from the United Kingdom (1). More cases have been detected in Karachi and Hyderabad as surveillance efforts have been strengthened, with recent reports increasing the number of cases to 5,372 (2). In the United States, in response to the reports from Pakistan, enhanced surveillance identified 29 patients with typhoid fever who had traveled to or from Pakistan during 2016-2018, including five with XDR Typhi. Travelers to areas with endemic disease, such as South Asia, should be vaccinated against typhoid fever before traveling and follow safe food and water practices. Clinicians should be aware that most typhoid fever infections in the United States are fluoroquinolone nonsusceptible and that the XDR Typhi outbreak strain associated with travel to Pakistan is only susceptible to azithromycin and carbapenems.