Background: On June 21st de-escalation measures and state-of-alarm ended in Spain after the COVID-19 first wave. New surveillance and control strategy was set up to detect emerging outbreaks. Aim: To detect and describe the evolution of COVID-19 clusters and cases during the 2020 summer in Spain. Methods: A near-real time surveillance system to detect active clusters of COVID-19 was developed based on Kulldorf’s prospective space-time scan statistic (STSS) to detect daily emerging active clusters. Results: Analyses were performed daily during the summer 2020 (June 21st – August 31st) in Spain, showing an increase of active clusters and municipalities affected. Spread happened in the study period from a few, low-cases, regional-located clusters in June to a nationwide distribution of bigger clusters encompassing a higher average number of municipalities and total cases by end-August. Conclusion: STSS-based surveillance of COVID-19 can be of utility in a low-incidence scenario to help tackle emerging outbreaks that could potentially drive a widespread transmission. If that happens, spatial trends and disease distribution can be followed with this method. Finally, cluster aggregation in space and time, as observed in our results, could suggest the occurrence of community transmission.

Background: By mid-September 2023, several event notifications related to cryptosporidiosis had been identified from different regions in Spain. Therefore, a request for urgent notification of cryptosporidiosis cases to the National Surveillance Network was launched. Aim: We aimed at assessing the extent of the increase in cases, the epidemiological characteristics and the transmission modes and compared to previous years. Methods: We analysed data on case notifications, outbreak reports and genotypes focusing on June–October 2023 and compared the results to 2016–2022. Results: In 2023, 4,061 cryptosporidiosis cases were notified in Spain, which is an increase compared to 2016–2022. The cumulative incidence was 8.3 cases per 100,000 inhabitants in 2023, sixfold higher than the median of 1.4 cases per 100,000 inhabitants 2016–2022. Almost 80% of the cases were notified between June and October. The largest outbreaks were related to contaminated drinking water or swimming pools. Cryptosporidium hominis was the most common species in the characterised samples (115/122), and the C. hominis IfA12G1R5 subtype, previously unusual in Spain, was detected from 76 (62.3%) of the 122 characterised samples. Conclusions: A substantial increase in cryptosporidiosis cases was observed in 2023. Strengthening surveillance of Cryptosporidium is essential for prevention of cases, to better understand trends and subtypes circulating and the impact of adverse meteorological events.

Background: After a national lockdown during the first wave of the COVID-19 pandemic in Spain, regional governments implemented different non-pharmaceutical interventions (NPIs) during the second wave.Aim: To analyse which implemented NPIs significantly impacted effective reproduction number (R_t) in seven Spanish provinces during 30 August 2020–31 January 2021.Methods: We coded each NPI and levels of stringency with a ‘severity index’ (SI) and computed a global SI (mean of SIs per six included interventions). We performed a Bayesian change point analysis on the R_tcurve of each province to identify possible associations with global SI variations. We fitted and compared several generalised additive models using multimodel inference, to quantify the statistical effect on R_tof the global SI (stringency) and the individual SIs (separate effect of NPIs).Results: The global SI had a significant lowering effect on the R_t(mean: 0.16 ± 0.05 units for full stringency). Mandatory closing times for non-essential businesses, limited gatherings, and restricted outdoors seating capacities (negative) as well as curfews (positive) were the only NPIs with a significant effect. Regional mobility restrictions and limited indoors seating capacity showed no effect. Our results were consistent with a 1- to 3-week-delayed R_tas a response variable.Conclusion: While response measures implemented during the second COVID-19 wave contributed substantially to a decreased reproduction number, the effectiveness of measures varied considerably. Our findings should be considered for future interventions, as social and economic consequences could be minimised by considering only measures proven effective.

Background: Botulism is a low incidence but potentially fatal infectious disease caused by neurotoxins produced mainly by Clostridium botulinum. There are different routes of acquisition, food-borne and infant/intestinal being the most frequent presentation, and antitoxin is the treatment of choice in all cases. In Spain, botulism is under surveillance, and case reporting is mandatory. Methods: This retrospective study attempts to provide a more complete picture of the epidemiology of botulism in Spain from 1997 to 2019 and an assessment of the treatment, including the relationship between a delay in antitoxin administration and the length of hospitalization using the Cox proportional hazards test and Kruskal–Wallis test, and an approach to the frequency of adverse events, issues for which no previous national data have been published. Results: Eight of the 44 outbreaks were associated with contaminated commercial foods involving ≤7 cases/outbreak; preserved vegetables were the main source of infection, followed by fish products; early antitoxin administration significantly reduces the hospital stay, and adverse reactions to the antitoxin affect around 3% of treated cases.

Background: Hepatitis E, a viral hepatitis caused mainly by the ingestion of raw or undercooked food, is not a notifiable disease in Spain. Aim: To analyse the temporal trends, epidemiological characteristics and factors associated with severe disease from hepatitis E hospitalisations in Spain from 1997 to 2019. Methods: Hospitalisation records were obtained from the Spanish National Hospital Discharge Database. Temporal trends and seasonality were analysed by Poisson regression in years 1997–2015 and 2016–19, given changes in hospital discharge databases. Multivariate logistic regression was used to identify factors associated with severe disease. Results: Hepatitis E hospitalisation incidence increased from 0.22 cases per 1,000,000 inhabitants in 1997 to a maximum of 2.95 in 2018. Seasonality was observed during 2016–19 period, with more cases in the second and third quarters of the year. The incidence was higher in men vs women, and in the population aged over 40 years. Factors independently associated with death were age ≥ 50 years (adjusted odds ratio (aOR): 2.43), chronic liver disease (aOR: 4.29), HIV infection (aOR: 3.00) and hepatitis B/C (aOR: 2.11). Conclusions: Hepatitis E hospitalisations have increased in Spain in recent years, being more severe in cases with older age, chronic hepatic diseases and HIV infection. A greater incidence in men over 40 years and a possible seasonality were observed. Further studies are needed to assess the seasonality, geographical distribution and impact of the disease to guide public health actions for prevention and control.

We compared the cumulative incidence and characteristics of hepatitis A outbreaks in two groups of Spanish autonomous regions according to whether a universal or risk group vaccination strategy was followed. Outbreaks between 2010 and 2018 were analyzed. The cumulative incidence rate of outbreaks was estimated and compared by estimating the rate ratio (RR). The characteristics of the outbreaks and those of the first cases were compared. Adjusted OR (aOR) were calculated using a multivariate logistic regression model. Outbreak incidence was 16.04 per million persons in regions with universal vaccination and 20.76 in those with risk-group vaccination (RR 0.77; 95%CI 0.62–0.94). Imported outbreaks accounted for 65% in regions with universal vaccination and 28.7% in regions with risk-group vaccination (aOR 3.88; 95%CI 2.13–7.09). Adolescents and young adults aged 15–44 years and men who have sex with men were less frequently the first case of the outbreak in regions with a universal vaccination strategy (aOR 0.54; 95%CI 0.32–0.92 and 0.23; 95%CI 0.07–0.82, respectively). The cumulative incidence rate of outbreaks was lower in regions with universal vaccination. In all regions, independently of the vaccination strategy, activities to vaccinate persons belonging to high-risk groups for infection should be emphasized.