Climate change impact on migration, travel, travel destinations and the tourism industry

Achieving net-zero agriculture in Africa: perspective on policies, challenges, and opportunities

Africa, with 55 Member States and over 1 billion people, is projected to nearly double its population to 2.5 billion by 2050, presenting both opportunities and challenges for sustainable development. Agriculture employs 65% of the labour force and contributes 32% to gross domestic product. The aim of this perspective is to highlight the challenges and opportunities of achieving net-zero agriculture in Africa while proffering appropriate recommendations. The primary issues are how extreme weather events affect food security and how to cut emissions from livestock farming as well as rice cultivation and fertilizer usage alongside evaluating current policies that support climate-smart agricultural practices. Africa needs to investigate how its expanding young population along with research and innovation can advance the move towards net-zero agricultural practices. Challenges of insufficient data availability together with ineffective policy enforcement, financial barriers, and limited awareness, decreasing precipitation levels coupled with regional conflicts and population migration hinder progress in achieving net-zero agriculture on the continent. However, Africa possesses substantial opportunities through its extensive arable land combined with its youthful workforce and renewable energy capabilities. Africa needs to obtain climate funds and strengthen regional partnerships while enhancing climate information services and creating inclusive and gender-responsive policies to address these issues. Investing in innovative technologies alongside renewable energy sources and crops resistant to climate change stands as an essential strategy. The implementation of early warning systems along with the development of alternative livelihoods will enhance efforts towards sustainable management of climate-induced migration. Africa will develop a climate-resilient agricultural system by confronting existing challenges while capitalizing on emerging opportunities.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11625-025-01666-y.

Tropical Diseases Wounds

Tropical diseases are no longer restricted to the tropics, and we have seen an emergency for many diseases in the United States. Increasing migration, international travel, tourism, and work visits to the tropical regions have contributed to the increase. Climate change and global warming may be causing tropical diseases and vectors to spread to areas previously spared. The last decade has shown a resurgence in tropical diseases in the United States. Many of these diseases will have symptoms affecting the skin.

[The effects of climate change on the emergence of dengue]

In recent decades, dengue has become a global issue due to its rapid spread and significant public health impact. Climate change is recognized as a key factor in the geographical spread of dengue and its vectors. Climate change affects dengue transmission through changes in temperature and precipitation, which affect both vectors and arboviruses. Climate change can also disrupt human migration patterns facilitating the spread of the virus and the invasion of vectors into new regions. Understanding the impact of climate change on dengue and its vectors is essential for developing strategies to prevent and control the disease. Appropriate mosquito control strategies, enhanced epidemiological surveillance and tailored public health systems are needed to mitigate the increasing burden of dengue in the context of climate change.

A randomized, double-blinded Phase 3 study to demonstrate lot-to-lot consistency and to confirm immunogenicity and safety of the live-attenuated chikungunya virus vaccine candidate VLA1553 in healthy adults†

BACKGROUND

The global spread of the chikungunya virus (CHIKV) increases the exposure risk for individuals travelling to or living in endemic areas. This Phase 3 study was designed to demonstrate manufacturing consistency between three lots of the single shot live-attenuated CHIKV vaccine VLA1553, and to confirm the promising immunogenicity and safety data obtained in previous trials.

METHODS

This randomized, double-blinded, lot-to-lot consistency, Phase 3 study, assessed immunogenicity and safety of VLA1553 in 408 healthy adults (18-45 years) in 12 sites across the USA. The primary endpoint was a comparison of the geometric mean titre (GMT) ratios of CHIKV-specific neutralizing antibodies between three VLA1553 lots at 28 days post-vaccination. Secondary endpoints included immunogenicity and safety over 6 months post-vaccination.

RESULTS

GMTs were comparable between the lots meeting the acceptance criteria for equivalence. The average GMT (measured by 50% CHIKV micro plaque neutralization test; μPRNT50) peaked with 2643 at 28 days post-vaccination and decreased to 709 at 6 months post-vaccination. An excellent seroresponse rate (defined as μPRNT50 titre ≥ 150 considered protective) was achieved in 97.8% of participants at 28 days post-vaccination and still persisted in 96% at 6 months after vaccination. Upon VLA1553 immunization, 72.5% of participants experienced adverse events (AEs), without significant differences between lots (related solicited systemic AE: 53.9% of participants; related solicited local AE: 19.4%). Overall, AEs were mostly mild or moderate and resolved without sequela, usually within 3 days. With 3.9% of participants experiencing severe AEs, 2.7% were classified as related, whereas none of the six reported serious adverse events was related to the administration of VLA1553.

CONCLUSIONS

All three lots of VLA1553 recapitulated the safety and immunogenicity profiles of a preceding Phase 3 study, fulfilling pre-defined consistency requirements. These results highlight the manufacturability of VLA1553, a promising vaccine for the prevention of CHIKV disease for those living in or travelling to endemic areas.

Occupational Health Challenges for Aviation Workers Amid the Changing Climate: A Narrative Review

Although there are many forecasts regarding the impact of climate change on the aviation sector, a critical but frequently neglected dimension is the occupational safety risks faced by aviation professionals. This narrative review explores the potential impacts of the changing climate on the health and safety of aviation personnel. Furthermore, we examine the significance of resilience in helping these workers adapt and effectively manage climate-related challenges in their professional lives. Climate change poses increasing threats to the well-being of flight personnel through elevated temperatures, heightened ultraviolet radiation exposure, increased mental workload from extreme weather events, and other psychological stressors. Building resilience through workforce training, planning, and adaptation can reduce vulnerability. In future research, the iterative process of selecting measurement components to gauge the impact of climate change should balance feasibility, relevance for stakeholders, and accurately capturing exposure effects. For instance, while salivary cortisol measures stress biologically, assessments of depression or burnout may provide more nuanced insights on pilot health for industry decision-makers managing climate impacts. In conclusion, a strategic emphasis on enhancing the physical and psychological well-being of the aviation workforce is imperative for facilitating a more efficient adaptation within the sector. This is of paramount importance, considering the critical function that aviation serves in fostering human connectivity. Consequently, it is essential for regulatory bodies and policymakers to prioritize the safeguarding of employee health in the face of climate change challenges.

Epidemiology of Dengue in Argentina during the 2010/11 to 2019/20 Seasons: A Contribution to the Burden of Disease

BACKGROUND

Dengue is an important public health problem in Argentina, as in many other countries. We reviewed and updated information on the dengue disease burden in Argentina over a 10-year period.

METHODS

We conducted a retrospective descriptive study from 2010 to 2020 based on data from the National Health Surveillance System. The main outcomes included dengue cases, incidence rates, deaths, and serotype distribution by season, age group, and region.

RESULTS

A total of 109,998 confirmed cases of dengue were reported. Seasonality stands out, prevailing during summer and autumn. Two main outbreaks (seasons 2015/16 and 2019/20), with increasing magnitude, were observed. The 2019/20 season showed the highest number of cases (58,731) and incidence rate (135/100,000). The Northeast region had the highest number of cases and incidence rate. In 2020, for the first time, autochthonous cases were registered in the Cuyo region. The only region with no autochthonous cases was the South. Adolescents and young adults showed the highest incidence rate. The case fatality rate for the period was 0.05%. Four serotypes circulated, but the predominant one was DEN-1 (78%).

CONCLUSIONS

Dengue has been expanding temporally and spatially. Although the DEN-1 serotype widely predominated, the increasing circulation of other serotypes raises concerns regarding re-exposure and the severity of future cases. Understanding epidemiological trends is key to defining public prevention and control policies.

Gaps and future directions in research on health effects of air pollution

Despite progress in many countries, air pollution, and especially fine particulate matter air pollution (PM2.5) remains a global health threat: over 6 million premature cardiovascular and respiratory deaths/yr. have been attributed to household and outdoor air pollution. In this viewpoint, we identify present gaps in air pollution monitoring and regulation, and how they could be strengthened in future mitigation policies to more optimally reduce health impacts. We conclude that there is a need to move beyond simply regulating PM2.5 particulate matter mass concentrations at central site stations. A greater emphasis is needed on: new portable and affordable technologies to measure personal exposures to particle mass; the consideration of a submicron (PM1) mass air quality standard; and further evaluations of effects by particle composition and source. We emphasize the need to enable further studies on exposure-health relationships in underserved populations that are disproportionately impacted by air pollution, but not sufficiently represented in current studies.

Climate change and vector-borne diseases: a multi-omics approach of temperature-induced changes in the mosquito

BACKGROUND

Climate change and globalization contribute to the expansion of mosquito vectors and their associated pathogens. Long spared, temperate regions have had to deal with the emergence of arboviruses traditionally confined to tropical regions. Chikungunya virus (CHIKV) was reported for the first time in Europe in 2007, causing a localized outbreak in Italy, which then recurred repeatedly over the years in other European localities. This raises the question of climate effects, particularly temperature, on the dynamics of vector-borne viruses. The objective of this study is to improve the understanding of the molecular mechanisms set up in the vector in response to temperature.

METHODS

We combine three complementary approaches by examining Aedes albopictus mosquito gene expression (transcriptomics), bacterial flora (metagenomics) and CHIKV evolutionary dynamics (genomics) induced by viral infection and temperature changes.

RESULTS

We show that temperature alters profoundly mosquito gene expression, bacterial microbiome and viral population diversity. We observe that (i) CHIKV infection upregulated most genes (mainly in immune and stress-related pathways) at 20°C but not at 28°C, (ii) CHIKV infection significantly increased the abundance of Enterobacteriaceae Serratia marcescens at 28°C and (iii) CHIKV evolutionary dynamics were different according to temperature.

CONCLUSION

The substantial changes detected in the vectorial system (the vector and its bacterial microbiota, and the arbovirus) lead to temperature-specific adjustments to reach the ultimate goal of arbovirus transmission; at 20°C and 28°C, the Asian tiger mosquito Ae. albopictus was able to transmit CHIKV at the same efficiency. Therefore, CHIKV is likely to continue its expansion in the northern regions and could become a public health problem in more countries than those already affected in Europe.

Climate Change and Travel: Harmonizing to Abate Impact

Purpose of Review

With climate change being the single biggest health threat facing humanity, this review aims to identify the climate-sensitive health risks to the traveler and to recognize the role that travel plays in contributing to the detrimental effects of climate change. With this understanding, adaptations for transformational action can be made.

Recent Findings

Travel and tourism, including transportation, food consumption, and accommodation, is responsible for a large percentage of the world’s carbon emissions which is contributing to the climate change crisis at an alarming rate. Climate change is a health emergency that is resulting in a rise of significant health impacts to the traveler including increased heat illnesses; food-, water-, and vector-borne diseases; and increasing risk of exposure to emerging infectious diseases. Patterns of future travel and destination choices are likely to change due to climactic factors such as temperature and extreme weather events, forced migration, degradation, and disappearance of popular and natural tourist destinations.

Summary

Global warming is and will continue to alter the landscape of travel medicine with expansion of transmission seasons and geographic ranges of disease, increased risk of infections and harmful marine toxins, and introduction of emerging infections to naïve populations. This will have implications for pre-travel counseling in assessing risk and discussing the environmental influences on travel. Travelers and stakeholders should be engaged in a dialogue to understand their “climate footprint,” to innovate sustainable solutions, and be empowered to make immediate, conscientious, and responsible choices to abate the impact of breaching critical temperature thresholds.

Public Health Preparedness in the Era of Weather Modification and Climate Engineering

The use of technological and chemical means aiming to achieve favorable weather conditions or reduce the risk of weather extremes is known as Weather Modification (WM). The United States of America, the People's Republic of China, Thailand, the United Arab Emirates, and Europe have employed WM in an effort to prevent hurricanes and storms, control precipitations, mitigate deforestation and drought, and enhance agriculture. Recently, the use of WM has been expanded toward decreasing air pollution and creating favorable weather conditions for major political and athletic events. The increasing significance and use of WM call for consideration upon its positive and negative effects on human health, close collaboration among health experts and WM decision makers, and relevant public health emergency contingency planning.

Intersections of climate change, migration, and health: experiences of first-generation migrants from Latin America to the Atlanta-metropolitan area

Climate change is an important driver of migration, but little research exists on whether migrant communities in the U.S. identify climate change-related factors as reasons for migrating. In 2021, we conducted a multidisciplinary, collaborative project to better understand the nexus of climate change and immigrant health in the Atlanta area. This paper presents one arm of this collaboration that explored both the role of climate change in decisions to immigrate to Georgia and the ways that climate change intersects with other possible drivers of migration. First generation migrants from Latin America were recruited primarily through CPACS Cosmo Health Center and were invited to participate in an intake survey and an in-depth interview. Results were analyzed using descriptive statistics and thematic analysis. Findings suggest that while participants may not have explicitly identified climate change as a primary reason for migration, in both surveys and in-depth interviews, participants reported multiple and intersecting social, economic, political, and environmental factors that are directly or indirectly influenced by climate change and that are involved in their decisions to migrate. The narratives that emerged from in-depth interviews further contextualised survey data and elucidated the complex nexus of climate change, migration, and health.

Cost-minimization analysis of DTaP-IPV-Hib combination vaccine in China: A nationwide cross-sectional study

Combination vaccines can reduce the vaccination visit, simplify the vaccination schedule and efficiently improve management. This study was primarily designed to evaluate the economic impact of integrating the diphtheria-tetanus-acellular pertussis inactivated poliomyelitis and Haemophilus influenzae type B (DTaP-IPV-Hib) combination vaccine into the China National Immunization Program. A cost-minimization analysis (CMA) compared the costs associated with direct medical, direct nonmedical, and indirect social costs in four schemes was conducted. A budgetary impact analysis assessed the alternative schemes' financial impact on the healthcare budget. Direct medical costs were extracted using a costing questionnaire and an observational time and motion chart. Direct nonmedical (cost for transportation) and indirect costs (loss of productivity) were derived from parents' questionnaires. Replacement of the current vaccination scheme with DTaP-IPV-Hib combination vaccine, resulted in net increases in direct medical costs of 77.64% for alternative scheme 1, 146.54% for alternative scheme 2, and 294.67% for alternative scheme 3, respectively. However, the direct nonmedical and indirect costs and the cost of the alternative schemes were 18.18%, 36.36%, and 63.64% lower than the current scheme for alternative scheme 1, alternative scheme 2, and alternative scheme 3, respectively. From the societal perspective, when compared with the current scheme, the budgetary impact of the three alternative schemes were +66 million Chinese Yuan (CNY) (4.81%), +103 million CNY (7.53%), and +305million CNY (22.35%), respectively. The CMA considered a broader perspective of social costs and indicated that the alternative schemes would result in an overall saving of parents' transportation and work loss costs to bring their children for vaccination, translating into a total cost saving of 18.18%, 36.36%, 63.64%, comparing to the current scheme. Thus, fully or partly using the DTaP-IPV-Hib combination vaccine is cost-saving in the context of China.

The Impact of Climate Change on Mental Health and Emotional Wellbeing: A Narrative Review of Current Evidence, and its Implications

Converging global evidence highlights the dire consequences of climate change for human mental health and wellbeing. This paper summarises literature across relevant disciplines to provide a comprehensive narrative review of the multiple pathways through which climate change interacts with mental health and wellbeing. Climate change acts as a risk amplifier by disrupting the conditions known to support good mental health, including socioeconomic, cultural and environmental conditions, and living and working conditions. The disruptive influence of rising global temperatures and extreme weather events, such as experiencing a heatwave or water insecurity, compounds existing stressors experienced by individuals and communities. This has deleterious effects on people's mental health and is particularly acute for those groups already disadvantaged within and across countries. Awareness and experiences of escalating climate threats and climate inaction can generate understandable psychological distress; though strong emotional responses can also motivate climate action. We highlight opportunities to support individuals and communities to cope with and act on climate change. Consideration of the multiple and interconnected pathways of climate impacts and their influence on mental health determinants must inform evidence-based interventions. Appropriate action that centres climate justice can reduce the current and future mental health burden, while simultaneously improving the conditions that nurture wellbeing and equality. The presented evidence adds further weight to the need for decisive climate action by decision makers across all scales.

The impact of cold weather on respiratory morbidity at Emory Healthcare in Atlanta

BACKGROUND

Research on temperature and respiratory hospitalizations is lacking in the southeastern U.S. where cold weather is relatively rare. This retrospective study examined the association between cold waves and pneumonia and influenza (P&I) emergency department (ED) visits and hospitalizations in three metro-Atlanta hospitals.

METHODS

We used a case-crossover design, restricting data to the cooler seasons of 2009-2019, to determine whether cold waves influenced ED visits and hospitalizations. This analysis considered effects by race/ethnicity, age, sex, and severity of comorbidities. We used generalized additive models and distributed lag non-linear models to examine these relationships over a 21-day lag period.

RESULTS

The odds of a P&I ED visit approximately one week after a cold wave were increased by as much as 11%, and odds of an ED visit resulting in hospitalization increased by 8%. For ED visits on days with minimum temperatures >20 °C, there was an increase of 10-15% in relative risk (RR) for short lags (0-2 days), and a slight decrease in RR (0-5%) one week later. For minimum temperatures <0 °C, RR decreased at short lags (5-10%) before increasing (1-5%) one week later. Hospital admissions exhibited a similar, but muted, pattern.

CONCLUSION

Unusually cold weather influenced P&I ED visits and admissions in this population.

The impact of climate change on visitor destination selection: A case study of the Central Drakensberg Region in KwaZulu-Natal

Many variables influence visitors’ destination choices, for example, affordability, attractions, health and safety, and expectancies. Amongst the indirect influences in destination choice by tourists, climate change is perhaps the greatest factor because of its negative impact on the ecological landscape of tourist destinations. Using the Central Drakensberg Region (CDR) as a case study, this article seeks to investigate the influence of climate change on visitors’ destination choices. A quantitative descriptive survey was conducted on a sample of n347 participants who were selected using purposive and convenience sampling procedures under the auspices of non-probability. The statistical analyses were performed using the latest edition of the Statistical Package for the Social Sciences (Version 25.0). Based on the study’s results, climate change was found to be a key influence on tourists’ decision-making, behaviour and spending habits at tourist destination like the Central Drakensberg Area. The most significant climatic parameter for tourists was determined to be pleasant and warm temperatures, as well as the summer season. Furthermore, owing to the current climate change circumstances, visitors were found to be less likely to return or recommend future visits to the region. To that end, tourism officials in the CDR should swiftly implement adaptation measures to counter the effects, and explore alternatives such as soft tourism and non-climate-dependent activities to accommodate visitors year-around. Further research is recommended to establish the extent to which socio-demographic characteristics influence destination choice in the area, as well as to ascertain the current state of climate change impacts.

Travelling to polluted cities: a systematic review on the harm of air pollution on international travellers' health

RATIONALE FOR REVIEW

In 2019, approximately, 1.4 billion people travelled internationally. Many individuals travel to megacities where air pollution concentrations can vary significantly. Short-term exposure to air pollutants can cause morbidity and mortality related to cardiovascular and respiratory disease, with the literature clearly reporting a strong association between short-term exposure to particulate matter ≤2.5 μm and ozone with adverse health outcomes in resident populations. However, limited research has been conducted on the health impacts of short-term exposure to air pollution in individuals who travel internationally. The objective of this systematic review was to review the evidence for the respiratory and cardiovascular health impacts from exposure to air pollution during international travel to polluted cities in adults aged ≥18 years old.

KEY FINDINGS

We searched PubMed, Scopus and EMBASE for studies related to air pollution and the health impacts on international travellers. Of the initially identified 115 articles that fit the search criteria, 6 articles were selected for the final review. All six studies found indications of adverse health impacts of air pollution exposure on international travellers, with most of the changes being reversible upon return to their home country/city. However, none of these studies contained large populations nor investigated vulnerable populations, such as children, elderly or those with pre-existing conditions.

CONCLUSIONS

More research is warranted to clearly understand the impacts of air pollution related changes on travellers' health, especially on vulnerable groups who may be at higher risk of adverse impacts during travel to polluted cities.

Geography Matters, But… Evolving Success Factors for Nature-Oriented Health Tourism within Selected Alpine Destinations

This paper analyzes the success factors of health tourism based on natural attractions in selected European spa and health destinations. The natural resources included in the offers, such as water, salt, and air, play a central role in this context, as their evidence-based effects have a high relevance for the health and wellbeing of tourists. Due to its specific geographical location and considering the threat of climate change, however, this offer is facing increasing challenges which make adaptation strategies necessary. In addition to a conceptional introduction to the topic, this paper contains a descriptive analysis of tourism statistics and the results from self-administered questionnaires with six selected representatives from alpine health destinations (DE, FR, IT, AT, CH, SI). The results show varying forms of health tourism based on natural attractions, which are also reflected in online marketing, with potential for optimization. The web research and the responses to the questionnaire revealed that evidence-based studies hardly play a role in promoting health touristic offers. Furthermore, climate change effects on natural attractions are considered extremely small and tend to prompt the development of new offers. Health destinations are advised to generate a clearer focus on the risks of climate change regarding natural resources.

Typhoid and paratyphoid fever: a clinical seminar

Rationale for review: Enteric fever (EF) caused by Salmonella enterica subspecies enterica serovar Typhi (Salmonella Typhi) and S. Paratyphi (Salmonella Paratyphi) remains an important cause of infectious morbidity and mortality in many low-income countries and, therefore, still poses a major infectious risk for travellers to endemic countries. Main findings: Although the global burden of EF has decreased over the past two decades, prevalence of EF remains high in Asia and Africa, with the highest prevalence reported from the Indian subcontinent. These statistics are mirrored by data on travel-related EF. Widespread and increasing antimicrobial resistance has narrowed treatment options for travel-related EF. Ceftriaxone- and azithromycin-based therapies are commonly used, even with the emergence of extremely drug-resistant typhoid in Pakistan. Preventive measures among locals and travellers include provision of safe food and water and vaccination. Food and water precautions offer limited protection, and the efficacy of Salmonella Typhi vaccines is only moderate signifying the need for travellers to be extra cautious. Recommendations: Improvement in the diagnosis of typhoid with high degree of clinical suspicion, better diagnostic assays, early and accurate detection of resistance, therapy with appropriate drugs, improvements in hygiene and sanitation with provision of safe drinking water in endemic areas and vaccination among travellers as well as in the endemic population are keys to controlling typhoid. While typhoid vaccines are recommended for travellers to high-risk areas, moderate efficacy and inability to protect against Salmonella Paratyphi are limitations to bear in mind. Improved Salmonella Typhi vaccines and vaccines against Salmonella Paratyphi A are required.

Global mobility, travel and migration health: clinical and public health implications for children and families

Exponential growth of the world's population combined with increased travel has dramatically increased the spread of infectious diseases. Although there has been significant focus on migration, the major contributors to the transmission of communicable diseases are travel and tourism not migration. Given that children represent up to 10% of international travellers, it is critical to the health of all age groups to ensure that tailored guidance for children is considered in public health policy and guidelines, and pandemic responses. To further support pandemic preparedness, public health systems need to strengthen ties with communities and health systems. In addition, travel and migration issues need to be included as core competencies in medical education. Ensuring that clinicians who care for children have knowledge of travel and migration health will foster a better health outcome in an increasingly mobile population at risk of emerging infectious diseases.Abbreviations CDC: Centers for Disease Control and Prevention; DGMQ: CDC Division of Global Migration and Quarantine; EID: emerging infectious diseases; EU: European Union; VFR: visiting friends and relatives; IOM: United Nations International Organization for Migration; LPR: lawful permanent resident; US: United States of America; WHO: World Health Organization.

COVID-19 in comparison with other emerging viral diseases: risk of geographic spread via travel

PURPOSE OF REVIEW

The COVID-19 pandemic poses a major global health threat. The rapid spread was facilitated by air travel although rigorous travel bans and lockdowns were able to slow down the spread. How does COVID-19 compare with other emerging viral diseases of the past two decades?

RECENT FINDINGS

Viral outbreaks differ in many ways, such as the individuals most at risk e.g. pregnant women for Zika and the elderly for COVID-19, their vectors of transmission, their fatality rate, and their transmissibility often measured as basic reproduction number. The risk of geographic spread via air travel differs significantly between emerging infectious diseases. COVID-19 is not associated with the highest case fatality rate compared with other emerging viral diseases such as SARS and Ebola, but the combination of a high reproduction number, superspreading events and a globally immunologically naïve population has led to the highest global number of deaths in the past 20 decade compared to any other pandemic.

What Is the Impact of Lockdowns on Dengue?

PURPOSE OF REVIEW

Societal lockdowns in response to the COVID-19 pandemic have led to unprecedented disruption to daily life across the globe. A collateral effect of these lockdowns may be a change to transmission dynamics of a wide range of infectious diseases that are all highly dependent on rates of contact between humans. With timing, duration and intensity of lockdowns varying country-to-country, the wave of lockdowns in 2020 present a unique opportunity to observe how changes in human contact rates, disease control and surveillance affect dengue virus transmission in a global natural experiment. We explore the theoretical basis for the impact of lockdowns on dengue transmission and surveillance then summarise the current evidence base from country reports.

RECENT FINDINGS

We find considerable variation in the intensity of dengue epidemics reported so far in 2020 with some countries experiencing historic low levels of transmission while others are seeing record outbreaks. Despite many studies warning of the risks of lockdown for dengue transmission, few empirically quantify the impact and issues such as the specific timing of the lockdowns and multi-annual cycles of dengue are not accounted for. In the few studies where such issues have been accounted for, the impact of lockdowns on dengue appears to be limited.

SUMMARY

Studying the impact of lockdowns on dengue transmission is important both in how we deal with the immediate COVID-19 and dengue crisis, but also over the coming years in the post-pandemic recovery period. It is clear lockdowns have had very different impacts in different settings. Further analyses might ultimately allow this unique natural experiment to provide insights into how to better control dengue that will ultimately lead to better long-term control.

Climate change and the origin of SARS-CoV-2

The origin of the severe acute respiratory syndrome coronavirus 2, the coronavirus that is still ravaging across the world almost a year after the first reported case, has been told in various ways—from the wildlife trade at the Wuhan wet market to the covert operations in laboratories. How does climate change fit in the narratives?

Dengue, chikungunya and Zika in GeoSentinel surveillance of international travellers: a literature review from 1995 to 2020

INTRODUCTION

GeoSentinel is a global surveillance network of travel medicine providers seeing ill-returned travellers. Much of our knowledge on health problems and infectious encountered by international travellers has evolved as a result of GeoSentinel surveillance, providing geographic and temporal trends in morbidity among travellers while contributing to improved pre-travel advice. We set out to synthesize epidemiological information, clinical manifestations and time trends for dengue, chikungunya and Zika in travellers as captured by GeoSentinel.

METHODS

We conducted a systematic literature search in PubMed on international travellers who presented with dengue, chikungunya or Zika virus infections to GeoSentinel sites around the world from 1995 until 2020.

RESULTS

Of 107 GeoSentinel publications, 42 articles were related to dengue, chikungunya and/or Zika. The final analyses and synthesis of and results presented here are based on the findings from 27 original articles covering the three arboviral diseases.

CONCLUSIONS

Dengue is the most frequent arboviral disease encountered in travellers presenting to GeoSentinel sites, with increasing trends over the past two decades. In Southeast Asia, annual proportionate morbidity increased from 50 dengue cases per 1000 ill returned travellers in non-epidemic years to an average of 159 cases per 1000 travellers during epidemic years. The highest number of travellers with chikungunya virus infections was reported during the chikungunya outbreak in the Americas and the Caribbean in the years 2013-16. Zika was first reported by GeoSentinel already in 2012, but notifications peaked in the years 2016-17 reflecting the public health emergency in the Americas at the time.

Implications of human activities for (re)emerging infectious diseases, including COVID-19

Since 1980, the world has been threatened by different waves of emerging disease epidemics. In the twenty-first century, these diseases have become an increasing global concern because of their health and economic impacts in both developed and resource-constrained countries. It is difficult to stop the occurrence of new pathogens in the future due to the interconnection among humans, animals, and the environment. However, it is possible to face a new disease or to reduce the risk of its spread by implementing better early warning systems and effective disease control and prevention, e.g., effective global surveillance, development of technology for better diagnostics, effective treatments, and vaccines, the global political will to respond to any threats and multidisciplinary collaboration involving all sectors in charge of good health maintenance. In this review, we generally describe some factors related to human activities and show how they can play a role in the transmission and spread of infectious diseases by using some diseases as examples. Additionally, we describe and discuss major factors that are facilitating the spread of the new pandemic known as COVID-19 worldwide.

A spatial-temporal study for the spread of dengue depending on climate factors in Pakistan (2006-2017)

BACKGROUND

In Pakistan, dengue fever has become a major concerning factor, given that it is a relatively new disease compared to malaria. The number of people affected by dengue fever has increased at least 10-fold in the last 15 years in specific areas of Pakistan. Therefore, it is necessary to analyse this disease to reduce or prevent the effects of dengue fever in the region.

METHODS

Geographical information system (GIS) maps are used to identify the intensity of the spread according to the count of affected people in our study area. Generalised linear modelling (GLM) is used to study the significance of factors associated with dengue fever.

RESULTS

The dengue virus is present throughout the year in specific areas of Pakistan. Karachi and Lahore are most significantly affected with cases in these two most populous cities of Pakistan reported every year. In the study period (2006-2017), 2011 was the most devastating year for Pakistan. Lahore recorded more than 17,000 confirmed cases with 290 deaths in a single year. The GLM analysis shows rainfall, the average maximum temperature, and hospitals to be significant factors in the prevalence of dengue fever.

CONCLUSION

This study finds that Sindh and Khyber Pakhtunkhwa are two of the primarily vulnerable provinces for the spread of dengue fever. Punjab has observed sporadic increases in dengue fever cases. In Pakistan, dengue cases increase in the rainfall season, especially during monsoon season. Lack of proper hospitals and clinics are another major factor, and mobile hospitals are needed in remote hotspot regions often affected by dengue fever. Finally, improved sanitation systems in metropoles would facilitate reducing breeding grounds for Aedes Aegypti larvae.

Modeling food growers' perceptions and behavior towards environmental changes and its induced risks: evidence from Pakistan

In Pakistan, rice is considered as the second staple food and provides livelihoods to the millions of the farm households. During recent years, rice production in Pakistan significantly decreased reportedly due to changes in climate and its induced risks. This study analyzed the incidence and severity of climate change and its induced risks in the rice-growing region of Pakistan and assessed farmers' perception and attitude by employing risk matrix and Equally Likely Certainty Equivalent model. According to the findings, the majority of the farmers were found risk-averse in behavior, while perceptions varied among different kinds of risks. Among the five kinds of risks, biological and financial risks were conceived as high risk, followed by the climate, biophysical, and social risk. Moreover, probit regression indicated farmers' age, education, landholding, off-farm income, advisory access, and credit utilization among the significant determinants of farmers' risk perceptions and attitudes. These findings suggest adopting a comprehensive approach with extended institutional and adaptation support to deal with various kinds of risks being faced by rice farmers in Pakistan. Graphical abstract.

Will flight shaming influence the future of air travel?

The concept of flight-shaming has emerged as part of efforts to promote more environmentally sustainable air travel. We argue that this approach may not have long-term merit and that instead the travel medicine community should raise awareness of the benefits of travel and support advances in eco-friendly jet fuel technology.

Migration Health: Highlights from Inaugural International Society of Travel Medicine (ISTM) Conference on Migration Health

PURPOSE OF REVIEW

International migration is a global phenomenon that is growing in scope, complexity and impact. The inaugural International Society of Travel Medicine (ISTM) International Conference on Migration Health provided a forum to discuss scientific evidence on the broad issues relevant to migration health. This review summarises the key health issues, with a focus on infectious diseases, current effective strategies and future considerations presented at this forum and in the recent literature.

RECENT FINDINGS

Migrants face health disparities for both communicable and non-communicable diseases. Their heightened infectious disease risks, compared to host populations, are related to pre-migration exposures, the circumstances of the migration journey and the receptivity and access to health services in their receiving countries. While the prevalence of infectious diseases identified through screening programmes are generally low, delays in diagnosis and treatment for a range of treatable infectious diseases result in higher morbidity and mortality among migrants. Barriers to care in host countries occur at the patient, provider and health systems levels. Coordinated and inclusive health services, healthcare systems and health policies, responsive to patient diversity reduce these barriers. Structural barriers to healthcare provision impede equitable care to migrants and refugees. Public health and medical professionals have a role in advocating for policy reforms.