Monkeypox, a zoonotic disease caused by an orthopoxvirus, results in a smallpox-like disease in humans. Since monkeypox in humans was initially diagnosed in 1970 in the Democratic Republic of the Congo (DRC), it has spread to other regions of Africa (primarily West and Central), and cases outside Africa have emerged in recent years. We conducted a systematic review of peer-reviewed and grey literature on how monkeypox epidemiology has evolved, with particular emphasis on the number of confirmed, probable, and/or possible cases, age at presentation, mortality, and geographical spread. The review is registered with PROSPERO (CRD42020208269). We identified 48 peer-reviewed articles and 18 grey literature sources for data extraction. The number of human monkeypox cases has been on the rise since the 1970s, with the most dramatic increases occurring in the DRC. The median age at presentation has increased from 4 (1970s) to 21 years (2010–2019). There was an overall case fatality rate of 8.7%, with a significant difference between clades—Central African 10.6% (95% CI: 8.4%– 13.3%) vs. West African 3.6% (95% CI: 1.7%– 6.8%). Since 2003, import- and travel-related spread outside of Africa has occasionally resulted in outbreaks. Interactions/activities with infected animals or individuals are risk behaviors associated with acquiring monkeypox. Our review shows an escalation of monkeypox cases, especially in the highly endemic DRC, a spread to other countries, and a growing median age from young children to young adults. These findings may be related to the cessation of smallpox vaccination, which provided some cross-protection against monkeypox, leading to increased human-to-human transmission. The appearance of outbreaks beyond Africa highlights the global relevance of the disease. Increased surveillance and detection of monkeypox cases are essential tools for understanding the continuously changing epidemiology of this resurging disease.

Based on notification data the impact of the COVID-19 lockdown in Switzerland was assessed. While the incidence of tick-borne encephalitis almost doubled as compared to 2016-2019, a reduction in all other infectious diseases was recorded. The lowest reduction rates (<25%) were noted for legionellosis, hepatitis A, chlamydia infection and gonorrhoea.

Travellers' diarrhoea (TD) is the most frequent illness experienced by international travellers to lower-income countries with bacterial agents considered to account for 80-90% of cases. In this review, we summarise evidence published on bacterial TD over the past 10 years, focusing on the epidemiology and aetiology of TD. Diarrhoeagenic Escherichia coli (DEC) continue to be the most commonly implicated bacteria in TD, although Enteropathogenic E. coli (EPEC) and Enteroaggregative E. coli (EAEC) now appear to be predominant where Enterotoxigenic E. coli (ETEC) was previously considered most prevalent globally. Where fluroquinolone resistance had primarily been documented for Campylobacter in Southeast Asia, widespread resistance has been observed in most regions of the world for multiple enteropathogens, including Shigella, Salmonella, ETEC and EAEC. Implementation of novel molecular methods for pathogen detection has led to identification of bacterial pathogens, including Clostridium difficile (with and without the use of prior antibiotics), Arcobacter species and Bacteroides fragilis, as aetiological agents in TD. The widespread resistance to first-line antibiotics in multiple bacterial enteropathogens warrants continued surveillance and re-evaluation of current treatment practices. Further investigations are required to determine the prevalence and geographical distribution of bacterial enteropathogens that have been more recently implicated in TD.

Tick-borne encephalitis (TBE) vaccination recommendations for children residing in high-endemicity countries in Europe vary from universal recommendations to none at all. Such differences may result in uncertainty about the value of such prevention among public health authorities, healthcare professionals and parents. We conducted a systematic review of publications and data from the European Centres for Disease Prevention and Control focusing on the epidemiology, clinical characteristics, and outcomes of TBE in a pediatric population. TBE can affect children of any age, occasionally even before the first birthday. Overall, the clinical course of disease is milder compared to adults, and there are fewer neurologic sequelae persisting after the infection. However, recent follow-up surveys identified a substantial proportion of children with long-term cognitive impairment subsequent to TBE infection. Fortunately, two vaccines against western TBE are available, and both are effective and safe. It is an overly simplistic perception that TBE is severe in adults and mild in children, and to therefore conclude that vaccination is important mainly in older age groups. Even if TBE infection is less dramatic in pediatric populations, TBE often results in long-standing cognitive damage. Based on guidance from the World Health Organization, authorities in countries with high endemicity should either offer or recommend TBE vaccination to children at 1-3 years of age.

Background: Infectious disease epidemiology is continuously shifting. While travel has been disrupted by the COVID-19 pandemic and travel-related epidemiological research experienced a pause, further shifts in vaccine-preventable diseases (VPDs) relevant for travellers have occurred. Methods: We conducted a literature search on the epidemiology of travel-related VPD and synthesized data for each disease with a focus on symptomatic cases and on the impact of the respective infection among travellers, considering the hospitalization rate, disease sequela and case fatality rate. We present new data and revised best estimates on the burden of VPD relevant for decisions on priorities in travel vaccines. Results: COVID-19 has emerged to be a top travel-related risk and influenza remains high in the ranking with an estimated incidence at 1% per month of travel. Dengue is another commonly encountered infection among international travellers with estimated monthly incidence of 0.5–0.8% among non-immune exposed travellers; the hospitalized proportion was 10 and 22%, respectively, according to two recent publications. With recent yellow fever outbreaks particularly in Brazil, its estimated monthly incidence has risen to >0.1%. Meanwhile, improvements in hygiene and sanitation have led to some decrease in foodborne illnesses; however, hepatitis A monthly incidence remains substantial in most developing regions (0.001–0.01%) and typhoid remains particularly high in South Asia (>0.01%). Mpox, a newly emerged disease that demonstrated worldwide spread through mass gathering and travel, cannot be quantified regarding its travel-related risk. Conclusion: The data summarized may provide a tool for travel health professionals to prioritize preventive strategies for their clients against VPD. Updated assessments on incidence and impact are ever more important since new vaccines with travel indications (e.g. dengue) have been licensed or are undergoing regulatory review.

Background: Tick-borne encephalitis (TBE) endemicity is spreading in Europe becoming an increasing health risk also for travellers. Previous reviews on TBE in civilian travellers lacked of numerator data and offered at most rough estimates on denominator data. An evidence-based quantification of the risk so far has been impossible; that resulted in fundamentally differing vaccination recommendations. Methods: A standard internet search was conducted with a focus on the data used to formulate vaccination recommendations. As TBE became notifiable at the European Union (EU) level the databases of European Center for Disease Prevention and Control (ECDC) were analysed for cases imported from abroad 2012. Since these included only 19 EU countries, individual experts were contacted in countries, which had not submitted data and additional surveillance databases were investigated to obtain a comprehensive account on travel-associated TBE in Central and Western Europe. Results: In 2012, the ECDC and other data sources included 38 reported cases of internationally acquired TBE. Basing on estimates of the exposed number of visitors, the attack rate for an undefined period of time could be very roughly extrapolated to be 0.5–1.3 per 100 000 (1 per 77 000–200 000) overall in Western/Central Europe endemic areas for the exposed at-risk population. Conclusions: As advised by the World Health Organization (WHO) travellers exposed outdoors in rural endemic areas to a risk of TBE during the period of transmission should be recommended immunization. In contrast, the advice to recommend TBE vaccination for all visitors of endemic areas is inappropriate. Implementation of the risk strategy is compromised by the fact that many at-risk travellers are unaware of the risk, thus they will not consult competent health professionals. Others may consult late, and in some countries of origin no TBE vaccine is marketed.