Non-cholera Vibrio (NCV) species are important causes of disease. These pathogens are thermophilic and climate change could increase the risk of NCV infection. The El Niño Southern Oscillation (ENSO) is a ‘natural experiment’ that may presage ocean warming effects on disease incidence. In order to evaluate possible climatic contributions to observed increases in NCV infection, we obtained NCV case counts for the United States from publicly available surveillance data. Trends and impacts of large-scale oceanic phenomena, including ENSO, were evaluated using negative binomial and distributed non-linear lag models (DNLM). Associations between latitude and changing risk were evaluated with meta-regression. Trend models demonstrated expected seasonality (P < 0.001) and a 7% (6.1%–8.1%) annual increase in incidence from 1999 to 2014. DNLM demonstrated increased vibriosis risk following ENSO conditions over the subsequent 12 months (relative risk 1.940, 95% confidence interval (CI) 1.298–2.901). The ‘relative–relative risk’ (RRR) of annual disease incidence increased with latitude (RRR per 10° increase 1.066, 95% CI 1.027–1.107). We conclude that NCV risk in the United States is impacted by ocean warming, which is likely to intensify with climate change, increasing NCV risk in vulnerable populations.

Consumption of seafood contaminated with Vibrio parahaemolyticus causes foodborne infections, which are on the rise owing to increased consumption of raw seafood in Asia, Europe, North America, and other regions. V. parahaemolyticus infections have been common in Japan since the 1960s. Following an epidemic in 1997, the Japanese Ministry of Health, Labour, and Welfare instituted regulations for seafood in 1999, which appear to be reducing V. parahaemolyticus infections. In this review, we describe the scientific findings for these regulations. Analyses of the V. parahaemolyticus serotypes and isolate characteristics in samples from infected patients and contaminated seafood are discussed. In addition, based on the results of a survey, we show that new food safety regulations have led to improvements in food hygiene at many seafood retail shops, food service facilities, and restaurants. This example from Japan could be of immense help to control foodborne infections in other countries.

To determine risk factors for sporadic Vibrio parahaemolyticus gastroenteritis, we conducted a population-based case-control study in sentinel hospital surveillance areas of Shanghai and Jiangsu province, China. Seventy-one patients with diarrhoea and confirmed V. parahaemolyticus infections were enrolled, and they were matched with 142 controls for gender, age and residential area. From the multivariable analysis, V. parahaemolyticus infections were associated with antibiotics taken during the 4 weeks prior to illness [odds ratio (OR) 8·1, 95% confidence interval (CI) 1·2–56·4)], frequent eating out (OR 3·3, 95% CI 1·1–10·1), and shellfish consumption (OR 3·2, 95% CI 1·0–9·9), with population-attributable fractions of 0·09, 0·25, and 0·14, respectively. Protective factors included keeping the aquatic products refrigerated (OR 0·4, 95% CI 0·1–0·9) and pork consumption (OR 0·2, 95% CI 0·1–0·8). Further study of the association of V. parahaemolyticus gastroenteritis with prior antibiotic use and shellfish consumption is needed.

Vibrio parahaemolyticus and Norovirus have been recognized as the cause of sporadic cases or outbreaks of diarrhoeal illness in association with the ingestion of raw or improperly cooked seafood. This report describes a foodborne outbreak of gastroenteritis caused by both Norovirus and Vibrio parahaemolyticus following the consumption of raw seafood in a restaurant in Terrassa (Catalonia, Spain) in September 2005. Measures are needed to reduce contamination of raw seafood. Consumers can reduce the risk of foodborne illness by avoiding consumption of raw or undercooked food.