Waterborne Infectious Diseases Associated with Exposure to Tropical Cyclonic Storms, United States, 1996-2018

Evacuation Decision-Making Post-COVID-19 Vaccine Availability: Implications of Compound Hazards in Puerto Rico and the US Virgin Islands

OBJECTIVE

The threat of novel pathogens and natural hazards is increasing as global temperatures warm, leading to more frequent and severe occurrences of infectious disease outbreaks and major hurricanes. The COVID-19 pandemic amplified the need to examine how risk perceptions related to hurricane evacuations shift when vaccines become available. This study explores individuals' expected evacuation plans during the early stages of COVID-19 vaccine availability.

METHODS

In March 2021, an online survey was disseminated in Puerto Rico and the US Virgin Islands.

RESULTS

An overwhelming majority (72.6%) of respondents said that their vaccination status would not affect their hurricane evacuation intentions. The unvaccinated were significantly more likely to consider evacuating during a hurricane than the vaccinated. Even with vaccines available, respondents suggested they were less likely to evacuate to a shelter during the 2021 season than prior to the COVID-19 pandemic. Respondents generally believed that the risk of contracting COVID-19 at a shelter was greater than the risk of sheltering-in-place during a hurricane.

CONCLUSIONS

Government officials need to develop and communicate clear information regarding evacuation orders for municipalities that may be more impacted than others based on the trajectory of the storm, social determinants of health, and other factors like living in a flood zone.

The impact of environmental changes on infectious diseases among children in North America

PURPOSE OF REVIEW

Climate change is no longer a distant threat but a present and accelerating force reshaping the epidemiology of infectious diseases in North America and elsewhere. Rising temperatures, shifting precipitation patterns, and extreme weather events are impacting the geographic distribution of pathogens and their vectors. Understanding these environmental influences on infectious diseases in children is essential for equipping healthcare providers to deliver competent care in the era of climate change.

RECENT FINDINGS

The northward spread of vector-borne diseases, warming waters and soils, and disease outbreaks following extreme weather events highlight the complex and multifactorial ways through which the environment influences the spread of infectious diseases.

SUMMARY

Continuing medical education and training on the evolving epidemiology of climate-sensitive diseases is critical for clinicians to address emerging health threats effectively. We advocate for more equitable funding and resource allocation to support innovative pediatric research on climate change and infectious diseases in the United States and other countries in North America.

A scoping review and thematic analysis of the effects of tropical cyclones on diarrheal diseases

Background

Tropical cyclones pose significant health risks and can trigger outbreaks of diarrheal diseases in affected populations. Although the effects of individual hazards, such as rainfall and flooding, on diarrheal diseases are well-documented, the complex multihazard nature of tropical cyclones is less thoroughly explored. To date, no dedicated review comprehensively examines the current evidence and research on the association between tropical cyclones and diarrheal diseases.

Methods

We performed a scoping review to map the literature on tropical cyclones and diarrheal diseases. A comprehensive literature search was performed across multiple online databases, including PubMed/MEDLINE, Web of Science, Scopus, Google Scholar, and ProQuest. We then performed a thematic analysis on the specific transmission pathways between tropical cyclones and diarrheal diseases as described in the literature.

Results

A total of 96 studies were included and categorized in this scoping review. Of these, 23 studies quantitatively assessed the association between tropical cyclones and diarrheal diseases, with more than half reporting a positive association. Additionally, we identified 30 studies that detailed transmission pathways, which we used for thematic analysis. Significant variability was observed in the definition of tropical cyclone exposure, with studies using different criteria such as an event, wind speed, or rainfall. Most studies used pre-post comparison designs without concurrent control groups, which can introduce limitations affecting internal validity by not accounting for temporal confounders. Diarrheal diseases can either increase or decrease during and after tropical cyclones, depending on the specific pathogens and the different strengths of tropical cyclones.

Conclusion

The variability in exposure definitions and study designs impedes the ability to quantitatively pool evidence. To improve the comparability and reliability of future research, we recommend that studies explore how different tropical cyclone exposure definitions impact results to identify the most appropriate metrics. We also suggest adopting more robust study designs, such as difference-in-difference or controlled interrupted time series for studying single tropical cyclone events, and case-crossover designs for studying multiple events. Additionally, studies examining specific causal pathways, such as integrating environmental sampling with health outcomes, should be explored to identify effective prevention strategies.

Large floods drive changes in cause-specific mortality in the United States

Flooding greatly endangers public health and is an urgent concern as rapid population growth in flood-prone regions and more extreme weather events will increase the number of people at risk. However, an exhaustive analysis of mortality following floods has not been conducted. Here we used 35.6 million complete death records over 18 years (2001-2018) from the National Center for Health Statistics in the United States, highly resolved flood exposure data and a Bayesian conditional quasi-Poisson model to estimate the association of flooding with monthly county-level death rates for cancers, cardiovascular diseases, infectious and parasitic diseases, injuries, neuropsychiatric conditions and respiratory diseases up to 3 months after the flood. During the month of flooding, very severe heavy rain-related floods were associated with increased infectious disease (3.2%; 95% credible interval (CrI): 0.1%, 6.2%) and cardiovascular disease (2.1%; 95% CrI: 1.3%, 3.0%) death rates and tropical cyclone-related floods were associated with increased injury death rates (15.3%; 95% CrI: 12.4%, 18.1%). During the month of very severe tropical cyclone-related flooding, increases in injury death rate were higher for those ≥65 years old (24.9; 95% CrI: 20.0%, 29.8%) than for those aged <65 years (10.2%; 95% CrI: 6.6%, 13.8%) and for females (21.2%; 95% CrI: 16.3%, 26.1%) than for males (12.6%; 95% CrI: 9.1%,16.1%). Effective public health responses are critical now and with projected increased flood severity driven by climate change.

Climate change, its impact on emerging infectious diseases and new technologies to combat the challenge

ABSTRACTImproved sanitation, increased access to health care, and advances in preventive and clinical medicine have reduced the mortality and morbidity rates of several infectious diseases. However, recent outbreaks of several emerging infectious diseases (EIDs) have caused substantial mortality and morbidity, and the frequency of these outbreaks is likely to increase due to pathogen, environmental, and population effects driven by climate change. Extreme or persistent changes in temperature, precipitation, humidity, and air pollution associated with climate change can, for example, expand the size of EID reservoirs, increase host-pathogen and cross-species host contacts to promote transmission or spillover events, and degrade the overall health of susceptible host populations leading to new EID outbreaks. It is therefore vital to establish global strategies to track and model potential responses of candidate EIDs to project their future behaviour and guide research efforts on early detection and diagnosis technologies and vaccine development efforts for these targets. Multi-disciplinary collaborations are demanding to develop effective inter-continental surveillance and modelling platforms that employ artificial intelligence to mitigate climate change effects on EID outbreaks. In this review, we discuss how climate change has increased the risk of EIDs and describe novel approaches to improve surveillance of emerging pathogens that pose the risk for EID outbreaks, new and existing measures that could be used to contain or reduce the risk of future EID outbreaks, and new methods to improve EID tracking during further outbreaks to limit disease transmission.

Infectious disease outbreaks in the wake of natural flood disasters: global patterns and local implications

Climate change is an urgent global health challenge, with floods becoming increasingly frequent and exacerbating the spread of infectious diseases. With its diverse climates and recurring natural disasters, Latin America is particularly susceptible to outbreaks following floods. These events disrupt ecosystems and create ideal conditions for the spread of waterborne and vector-borne pathogens. Floods also damage infrastructure, displace populations, and restrict access to clean water and healthcare services, further compounding public health risks. This review assesses the impact of floods on infectious disease outbreaks in Latin America, focusing on key epidemiological trends, vulnerabilities, and strategies for mitigation. This narrative review aims to analyse the incidence and transmission of infectious diseases during and after floods in Latin America. Particular emphasis is placed on waterborne diseases, such as cholera and leptospirosis, vector-borne diseases, including dengue and malaria, and respiratory infections in displaced populations. The review also considers how socioeconomic factors, healthcare limitations, and climate vulnerabilities amplify the public health risks in flood-affected regions. We extensively searched PubMed, Google Scholar, Scopus, Science Direct, and Web of Science from 2010 to May 2024, examining articles in English, Spanish, and Portuguese. The search focused on original descriptive studies on flooding and infectious diseases, particularly in Latin America. Keywords such as 'flooding,' 'waterborne diseases,' 'vector-borne diseases,' 'skin and soft tissue infections,' 'respiratory infections,' and specific disease names like leishmaniasis and malaria were employed. A descriptive analysis of the relevant articles was performed to synthesise the key findings. The results show a clear association between floods and infectious disease outbreaks in several countries. Waterborne diseases, especially cholera and leptospirosis, are frequently reported following floods due to contaminated water. Vector-borne diseases like dengue and malaria see increased transmission as stagnant water forms ideal breeding grounds for mosquitoes. Respiratory infections are also prevalent in overcrowded, unsanitary shelters for displaced populations. Additionally, fungal infections and skin diseases are notable concerns, especially in areas with prolonged exposure to floodwaters. Floods disproportionately affect vulnerable populations, particularly low-income areas with insufficient infrastructure and limited healthcare access. Climate change is likely to intensify the frequency and severity of floods further, increasing the health risks. Finally, this review underscores the critical need for improved disaster preparedness, enhanced healthcare infrastructure, and better water and sanitation systems in flood-prone regions. Strengthening public health interventions and implementing climate adaptation strategies are essential to mitigating the impact of infectious diseases in future flood events.

The Adequacy of Current Legionnaires' Disease Diagnostic Practices in Capturing the Epidemiology of Clinically Relevant Legionella: A Scoping Review

Legionella is an underdiagnosed and underreported etiology of pneumonia. Legionella pneumophila serogroup 1 (LpSG1) is thought to be the most common pathogenic subgroup. This assumption is based on the frequent use of a urinary antigen test (UAT), only capable of diagnosing LpSG1. We aimed to explore the frequency of Legionella infections in individuals diagnosed with pneumonia and the performance of diagnostic methods for detecting Legionella infections. We conducted a scoping review to answer the following questions: (1) "Does nucleic acid testing (NAT) increase the detection of non-pneumophila serogroup 1 Legionella compared to non-NAT?"; and (2) "Does being immunocompromised increase the frequency of pneumonia caused by non-pneumophila serogroup 1 Legionella compared to non-immunocompromised individuals with Legionnaires' disease (LD)?". Articles reporting various diagnostic methods (both NAT and non-NAT) for pneumonia were extracted from several databases. Of the 3449 articles obtained, 31 were included in our review. The most common species were found to be L. pneumophila, L. longbeachae, and unidentified Legionella species appearing in 1.4%, 0.9%, and 0.6% of pneumonia cases. Nearly 50% of cases were caused by unspecified species or serogroups not detected by the standard UAT. NAT-based techniques were more likely to detect Legionella than non-NAT-based techniques. The identification and detection of Legionella and serogroups other than serogroup 1 is hampered by a lack of application of broader pan-Legionella or pan-serogroup diagnostics.

Autoimmune Diseases Following Environmental Disasters: A Narrative Review of the Literature

Environmental disasters are extreme environmental processes such as earthquakes, volcanic eruptions, landslides, tsunamis, floods, cyclones, storms, wildfires and droughts that are the consequences of the climate crisis due to human intervention in the environment. Their effects on human health have alarmed the global scientific community. Among them, autoimmune diseases, a heterogeneous group of disorders, have increased dramatically in many parts of the world, likely as a result of changes in our exposure to environmental factors. However, only a limited number of studies have attempted to discover and analyze the complex association between environmental disasters and autoimmune diseases. This narrative review has therefore tried to fill this gap. First of all, the activation pathways of autoimmunity after environmental disasters have been analyzed. It has also been shown that wildfires, earthquakes, desert dust storms and volcanic eruptions may damage human health and induce autoimmune responses to inhaled PM2.5, mainly through oxidative stress pathways, increased pro-inflammatory cytokines and epithelial barrier damage. In addition, it has been shown that heat stress, in addition to increasing pro-inflammatory cytokines, may also disrupt the intestinal barrier, thereby increasing its permeability to toxins and pathogens or inducing epigenetic changes. In addition, toxic volcanic elements may accelerate the progressive destruction of myelin, which may potentially trigger multiple sclerosis. The complex and diverse mechanisms by which vector-borne, water-, food-, and rodent-borne diseases that often follow environmental diseases may also trigger autoimmune responses have also been described. In addition, the association between post-disaster stress and the onset or worsening of autoimmune disease has been demonstrated. Given all of the above, the rapid restoration of post-disaster health services to mitigate the flare-up of autoimmune conditions is critical.

NPCC4: Climate change and New York City's health risk

This chapter of the New York City Panel on Climate Change 4 (NPCC4) report considers climate health risks, vulnerabilities, and resilience strategies in New York City's unique urban context. It updates evidence since the last health assessment in 2015 as part of NPCC2 and addresses climate health risks and vulnerabilities that have emerged as especially salient to NYC since 2015. Climate health risks from heat and flooding are emphasized. In addition, other climate-sensitive exposures harmful to human health are considered, including outdoor and indoor air pollution, including aeroallergens; insect vectors of human illness; waterborne infectious and chemical contaminants; and compounding of climate health risks with other public health emergencies, such as the COVID-19 pandemic. Evidence-informed strategies for reducing future climate risks to health are considered.

An outbreak of Shiga toxin-producing Escherichia coli (STEC) O157:H7 associated with contaminated lettuce and the cascading risks from climate change, the United Kingdom, August to September 2022

Shiga-toxin producing Escherichia coli (STEC) O157 is a food-borne pathogen which causes gastrointestinal illness in humans. Ruminants are considered the main reservoir of infection, and STEC exceedance has been associated with heavy rainfall. In September 2022, a large outbreak of STEC O157:H7 was identified in the United Kingdom (UK). A national-level investigation was undertaken to identify the source of the outbreak and inform risk mitigation strategies. Whole genome sequencing (WGS) was used to identify outbreak cases. Overall, 259 cases with illness onset dates between 5 August and 12 October 2022, were confirmed across the UK. Epidemiological investigations supported a UK grown, nationally distributed, short shelf-life food item as the source of the outbreak. Analytical epidemiology and food chain analysis suggested lettuce as the likely vehicle of infection. Food supply chain tracing identified Grower X as the likely implicated producer. Independent of the food chain investigations, a novel geospatial analysis triangulating meteorological, flood risk, animal density and land use data was developed, also identifying Grower X as the likely source. Novel geospatial analysis and One Health approaches are potential tools for upstream data analysis to predict and prevent contamination events before they occur and to support evidence generation in outbreak investigations.

Risks of infectious disease hospitalisations in the aftermath of tropical cyclones: a multi-country time-series study

BACKGROUND

The proportion of intense tropical cyclones is expected to increase in a changing climate. However, there is currently no consistent and comprehensive assessment of infectious disease risk following tropical cyclone exposure across countries and over decades. We aimed to explore the tropical cyclone-associated hospitalisation risks and burden for cause-specific infectious diseases on a multi-country scale.

METHODS

Hospitalisation records for infectious diseases were collected from six countries and territories (Canada, South Korea, New Zealand, Taiwan, Thailand, and Viet Nam) during various periods between 2000 and 2019. The days with tropical cyclone-associated maximum sustained windspeeds of 34 knots or higher derived from a parametric wind field model were considered as tropical cyclone exposure days. The association of monthly infectious diseases hospitalisations and tropical cyclone exposure days was first examined at location level using a distributed lag non-linear quasi-Poisson regression model, and then pooled using a random-effects meta-analysis. The tropical cyclone-attributable number and fraction of infectious disease hospitalisations were also calculated.

FINDINGS

Overall, 2·2 million people who were hospitalised for infectious diseases in 179 locations that had at least one tropical cyclone exposure day in the six countries and territories were included in the analysis. The elevated hospitalisation risks for infectious diseases associated with tropical cyclones tended to dissipate 2 months after the tropical cyclone exposure. Overall, each additional tropical cyclone day was associated with a 9% (cumulative relative risk 1·09 [95% CI 1·05-1·14]) increase in hospitalisations for all-cause infectious diseases, 13% (1·13 [1·05-1·21]) for intestinal infectious diseases, 14% (1·14 [1·05-1·23]) for sepsis, and 22% (1·22 [1·03-1·46]) for dengue during the 2 months after a tropical cyclone. Associations of tropical cyclones with hospitalisations for tuberculosis and malaria were not significant. In total, 0·72% (95% CI 0·40-1·01) of the hospitalisations for all-cause infectious diseases, 0·33% (0·15-0·49) for intestinal infectious diseases, 1·31% (0·57-1·95) for sepsis, and 0·63% (0·10-1·04) for dengue were attributable to tropical cyclone exposures. The attributable burdens were higher among young populations (aged ≤19 years) and male individuals compared with their counterparts, especially for intestinal infectious diseases. The heterogeneous spatiotemporal pattern was further revealed at the country and territory level-tropical cyclone-attributable fractions showed a decreasing trend in South Korea during the study period but an increasing trend in Viet Nam, Taiwan, and New Zealand.

INTERPRETATION

Tropical cyclones were associated with persistent elevated hospitalisation risks of infectious diseases (particularly sepsis and intestinal infectious diseases). Targeted interventions should be formulated for different populations, regions, and causes of infectious diseases based on evidence on tropical cyclone epidemiology to respond to the increasing risk and burden.

FUNDING

Australian Research Council, Australian National Health, and Medical Research Council.