1. Introduction

Zoonotic diseases, characterized by their ability to be transmitted from animals to humans, have persistently presented substantial risks to worldwide public health. Public health professionals and academics must pay close attention to these diseases, as they can cross species barriers. The challenges in predicting the emergence and dissemination of zoonotic illnesses are compounded by their erratic behavior and intricate patterns, as elucidated in the research conducted by Sikkema and Koopmans [1]. The inherent unpredictability of certain phenomena can occasionally result in rapid global outbreaks. Failure to promptly execute preventive measures or interventions may lead to the emergence of severe pandemics, which can have significant societal and economic consequences on a worldwide scale [1]. Alterations in human social processes, whether gradually or abruptly, such as transformations in the meat business or military conquests, can engender zoonotic pandemics and novel infectious diseases in humans.

Amidst the political and social disruptions in countries affected by severe conflicts and wars, a significant and concealed problem arises: the increasing threat of zoonotic diseases, which are exacerbated by the patterns of migration resulting from the ongoing conflicts. The movement of substantial populations in response to upheaval results in an inadvertent outcome: ecosystems experience disruption and the demarcation between urban regions and wildlife habitats becomes increasingly indistinct. The act of intermingling not only threatens the ecological equilibrium, but also creates opportunities for the emergence and dissemination of new illnesses. The combination of human migration, ecological disturbance, and habitat overlap creates a suitable environment for transmitting illnesses from animals to humans, posing a significant health risk that may persist after resolving the conflict. In the present review, we will shed light on how the ongoing wars increase the risk of infection by zoonotic diseases (Figure 1).

2. Exposure to New Pathogens From Different Regions

In the aftermath of the recent wars, a significant number of citizens have been compelled to seek asylum in other regions. The escalating mobility of human populations has led to a heightened apprehension over the dissemination of infections across different geographical zones. When significant populations experience displacement, there exists an increased susceptibility not only to the direct transmission of diseases carried by humans, but also to a possible upsurge in zoonotic diseases [2]. Migration is a fundamental element of the human experience, marked by the displacement of persons from one geographical area to another. When analyzing regions embroiled in conflict, the complexities surrounding migration become heightened. The phenomenon described here extends beyond mere migration between urban areas, encompassing movements across various locations, each characterized by its unique assortment of infections. When confronted with armed conflicts, the act of residents being forced to leave their houses extends beyond the simple act of moving their personal belongings. Many individuals may unknowingly be unintentionally carrying germs. These imperceptible hitchhikers can materialize in several manifestations, encompassing viruses, bacteria, or parasites. It is important to note that certain infections can cause evident diseases, whereas others can exist within hosts without producing obvious symptoms, thus, enabling their transmission to other areas and populations without detection.

Armed conflict’s consequences reach beyond the immediate and obvious destruction, impacting critical industries such as healthcare. Healthcare systems in areas affected by conflicts have seen significant disruptions. The fundamental components of medical support, such as hospitals, clinics, and other healthcare facilities, confront twofold obstacles: some have been destroyed, while others contend with an immense surge in injured individuals. Consequently, the typical rhythm of healthcare delivery experiences a substantial modification. Health checks, commonly regarded as the initial means of protection against diseases, tend to be overshadowed [3].

Similarly, vaccination campaigns, which are crucial in mitigating the occurrence of infectious disease epidemics, may encounter disruptions or may not be executed with the same level of meticulousness as during periods of tranquility [4]. Furthermore, certain preventive healthcare initiatives, which play a crucial role in protecting the well-being of the general population, encounter obstacles. As a result, these systemic disruptions render the populace more susceptible and increase their likelihood of succumbing to various illnesses [5].

The merging of urban and natural ecosystems has become a significant concern in contemporary conflicts. Wars and ongoing conflicts often motivate individuals to pursue safety, leading them to areas that have not been previously impacted by human activity or regions that have mostly functioned as sanctuaries for various wildlife species [6]. As human populations establish themselves in certain geographical areas, they unintentionally infringe upon the ecological niches of various animal species. The recent spatial closeness between human populations and wildlife has resulted in heightened levels of interaction, thus, leading to an augmented susceptibility to zoonotic diseases. Zoonotic spillover events pertain to occurrences in which infections, initially harbored by animals, successfully establish infection in humans. These occurrences are of special significance due to their potential to give rise to unknown diseases against which humans may possess limited immunity. The convergence of human and wildlife habitats, driven by the destructive consequences of warfare, raises the likelihood of such spillover incidents, presenting significant health hazards to displaced communities and perhaps giving rise to more extensive public health emergencies.

The persistent violence has significantly influenced multiple areas, including the crucial field of wildlife observation. Countries affected by recent armed conflicts are renowned for their diverse and abundant fauna and have historically served as a fertile environment for the emergence and transmission of zoonotic illnesses. The importance of ongoing and comprehensive surveillance of wildlife health is underscored by zoonotic illnesses, which can be transmitted from animals to people. Moreover, understanding the complex movement patterns exhibited by animals and diving into their habits yields vital information that might proactively anticipate and manage the dangers associated with zoonotic outbreaks [7]. Unfortunately, many ongoing conflicts have presented many obstacles that impede the pursuit of these crucial academic endeavors. The capacity of researchers and professionals to regularly observe and assess animal health and behavior has been significantly hindered by the prevailing instability in these regions [8]. The interruption of surveillance systems has the potential to result in undetected risks, ultimately leading to unanticipated occurrences of zoonotic outbreaks. Hence, the ramifications of the battle transcend immediate human casualties and geopolitical implications, presenting an underlying peril to public health as it potentially facilitates the uncontrolled proliferation of zoonotic diseases.

As animals expand their range into previously unexplored habitats, many of them are increasingly encountering human populations in closer proximity. Given the challenging circumstances, it is imperative to comprehend and recognize the potential hazards linked to zoonotic illnesses inside areas affected by armed conflicts. It is imperative to adopt a diverse approach while implementing prevention techniques. On the one hand, increased surveillance of humans and animals must be increased. Mobile health units can play a significant role in ensuring that people get the necessary vaccinations and health checks. Conversely, it is imperative to undertake initiatives to impart knowledge to the general populace regarding the potential hazards of intimate interactions with fauna. Implementing basic preventive measures such as refraining from ingesting wild animals, adhering to proper hygiene practices, and promptly seeking medical assistance upon the onset of symptoms can significantly contribute to preventing outbreaks.

3. The Potential Role of Anthropic Factors in Increasing the Risk of Zoonotic Diseases During Some Recent Conflicts

According to the World Organization for Animal Health (WAOH), 75% of newly discovered illnesses are zoonotic—they come from domestic or wild animals. This underscores how vital it is for authorities in charge of animal health and those concerned with public health to work together closely [9]. Most recent armed conflicts have far-reaching effects on public health, the environment, and human lives, in addition to international politics [10]. For example, the Ukraine–Russia conflict has been ongoing for more than 10 years and is characterized by military clashes, political unrest, and humanitarian crises [10].

The conflicts in Sudan and in Gaza have resulted in thousands of deaths, injuries, and the displacement of people [11]. This mass displacement of populations, often to overcrowded camps with poor sanitation, increases human–animal contact and creates ideal conditions for the transmission of zoonotic diseases. Disruption of food systems and reduced access to healthcare further heighten the risk of disease outbreaks. Conflicts also damage veterinary infrastructure and services, hampering the ability to monitor animal health and control diseases that could spill over into human populations. Comprehensive surveillance of both human and animal health is critical to anticipate and manage the risks of zoonotic disease transmission in conflict-affected regions like Sudan [11, 12].

Szewczyk et al. [13] reported that the Ukraine conflict has caused significant ecological damage, including damage to infrastructure and the Chernobyl exclusion zone, releasing radioactive substances and posing risks to wildlife. The displacement of human populations and lack of maintenance have increased wildlife–human interactions. Ukraine’s ongoing war severely impacts the agricultural sector, causing farmers to face challenges and food shortages, leading some communities to seek alternative food sources and potentially increasing the risk of zoonotic diseases [14]. According to Sandvik [15], the ongoing conflict in Ukraine has led to overcrowded living conditions in refugee camps and urban areas, facilitating the spread of zoonotic illnesses through respiratory pathways or close contact between humans and livestock. Zubach et al. [16] highlighted a rare case of leptospirosis that was reported in a Ukrainian civilian during a conflict involving exposure to gray rats in basements. Despite delayed diagnosis and treatment, the case highlights the importance of vigilance in monitoring emerging infectious diseases in conflict-driven living conditions. Deforestation increases zoonotic disease risk due to habitat destruction and transformation into anthropic ecosystems, causing a significant distraction from natural forest ecosystems [17].

The chaos created by wars makes proper surveillance of animal populations difficult, leading to incidents like contaminated animal vaccines in South Sudan in 2017. The conflict has also forced researchers and veterinary professionals to flee Sudan, hindering their capacity to observe and assess animal health and behavior regularly. This exodus of experts has further exacerbated the challenges in managing the risks of zoonotic disease transmission in the region [18].

4. Destruction of Ecosystems During the Recent Wars Increase the Risk of Zoonotic Diseases’ Emergence and Transmission

The whole world is suffering from the devastating effects of recent wars. The global economy is facing the most crisis period. The recent wars have brought about huge political and humanitarian crises and especially exerted profound ecological repercussions [19]. This may impact the destruction of ecosystems and increase the risk of zoonotic diseases amidst the migratory waves in Africa and Eastern Europe.

The resultant influx of refugees often destroys infrastructure and habitats, which in turn causes wildlife to flee or adapt to new environments, often making them come in close contact with human and domestic animals. Therefore, wildlife migration can significantly impact human–wildlife interactions because of increased encounters between people and animals in new and unfamiliar settings. These interactions can raise the risk of zoonotic disease spillover, which occurs when a disease that typically affects animals is transmitted to humans. In addition, such interactions may also contribute to the transmission of antimicrobial resistance (AMR). Populations of many rare migratory and endemic species are suffering heavy losses. Many species of birds were forced to abandon their natural habitat and nests and change their usual migration routes. War-related activities, such as deforestation and tunnel excavation, contribute to habitat degradation and fragmentation [20]. This degradation can disrupt natural ecosystems, destabilize food chains, and force wildlife into proximity with food animals, potentially facilitating the transmission of new foodborne pathogens. The altered landscape and ecological stressors stemming from conflict can impact the health of wildlife populations. The industrial or populated area may impact the decline in wild species’ richness and habitat [21]. Stress and malnutrition in wildlife can weaken their immune systems, making them more susceptible to infections, including zoonotic diseases. This weakened state may increase the likelihood of disease spillover to humans [22]. Belligerents sometimes take advantage of the chaos of war for poaching and trafficking of animal products [21]. This can lead to increased hunting, trapping, and trading of wildlife, potentially introducing zoonotic pathogens into new regions and markets, where human consumption may expose individuals to novel diseases [23].

5. The Impact of Inadequate Sanitation on the Emergence of Zoonotic Diseases During the Recent War

The lack of sanitation for migrants of war in conflict countries can have significant consequences, including increased risks of zoonotic diseases [24]. From a public health perspective, many aspects may be considered, including inadequate sanitation facilities, such as access to clean water and proper toilets, which can spread various diseases [25, 26]. Migrants living in crowded and unsanitary conditions are at a higher risk of contracting and spreading infectious diseases, including respiratory infections, diarrheal diseases, and skin infections. These conditions can affect not only the migrants but also the host communities and neighboring regions with their consequent risk, as demonstrated in previous situations. Many foodborne and waterborne diseases are also zoonotic (e.g., brucellosis and leptospirosis) [27]. It is worth noting that many Russian soldiers may have caught anthrax spores, while excavating trenches in the Zaporozhye region. Additionally, there are many unburned anthrax-infected livestock burials in Ukraine. Any digging in these areas will spread illness not just among the occupants but also among the neighboring people.

War and displacement often disrupt ecosystems and may lead to closer contact between humans and animals, increasing the risk of zoonotic disease transmission [28–30]. Poor sanitation practices and lack of clean water can exacerbate this risk, leading to contaminated water sources, improper disposal of animal waste, and increased exposure to disease vectors like insects and arthropods [31–33]. Inadequate sanitation and hygiene can also lead to issues with food safety. Improper handling, storage, and food preparation can result in foodborne illnesses, which can be particularly dangerous when limited or overwhelmed by healthcare and medical facilities [34, 35].

The lack of access to basic sanitation facilities can also have a detrimental effect on the mental and emotional well-being of migrants. It can lead to stress, anxiety, and insecurity as people live in unsanitary and overcrowded conditions. Living in such conditions increases zoonotic disease risk [36, 37]. Access to clean water and sanitation is considered a basic human right. The lack of these essential services can strip migrants of dignity, exacerbate their hardships due to conflict and displacement, and lead to waterborne diseases, including zoonoses. It can also contribute to feelings of marginalization and social exclusion [38, 39].

Poor sanitation and the associated health risks can have long-term implications for the health of migrants. This includes the potential for chronic health problems, developmental issues in children, and increased mortality rates. Addressing the lack of sanitation and mitigating the risks of zoonotic diseases among migrants in conflict countries is crucial for their well-being, public health, and regional stability. Humanitarian organizations and governments should work together to provide clean water, adequate sanitation facilities, and education on hygiene practices to mitigate these risks and improve the overall living conditions of migrants. Additionally, efforts to address zoonotic disease risks may involve increased surveillance, vaccination programs for animals, and public health campaigns to minimize contact between humans and potentially infected animals [40–43].

6. Impacts of Recent Wars on the Emergence of Diseases

Several diseases have reemerged as a result of the recent conflicts, such as cholera, tuberculosis, hepatitis, poliomyelitis, measles, human immunodeficiency virus (HIV), and multidrug-resistant (MDR) bacteria. In this section, we will shed light on the impact of recent conflicts on these diseases.

7. Conclusions

The migratory wave in Eastern Europe amidst the war in conflict countries presents a multifaceted challenge from a humanitarian and political perspective regarding its ecological implications. The destruction of ecosystems, wildlife displacement, habitat degradation, and altered disease dynamics contribute to an elevated risk of zoonotic disease emergence and transmission in the region. Urbanization, deforestation, climate change, and intensive agricultural practices continue to shape the landscape of zoonotic disease emergence and spread (Figure 1). As the global population grows and food demand increases, the intensification of agriculture and the expansion of livestock production systems create new occasions for pathogen transmission. These systems can also expose workers and nearby residents to heightened health risks. Awareness, surveillance, and sustainable practices are imperative to mitigate these risks. In this ever-evolving world, where human activities increasingly impact the natural environment, understanding the factors driving zoonotic diseases is crucial for preventing and managing outbreaks. A collaborative effort involving public health authorities, environmental agencies, and the agricultural sector is essential to protect human and animal health and maintain the delicate balance of our interconnected ecosystems in general, particularly in countries affected by wars.

Conflicts of Interest

The authors declare no conflicts of interest.

Author Contributions

Sina Salajegheh Tazerji, Phelipe Magalhães Duarte, and Awad A. Shehata contributed to conceptualization, funding acquisition, project administration, supervision, visualization, writing–original draft, writing–review and editing. Rasha Gharieb, Lukasz Szarpak, Michal Pruc, Md. Tanvir Rahman, Alfonso J. Rodriguez-Morales, Muhammad Furqan Ilyas, Maria de Nazaré Santos Ferreira, Yashpal Singh Malik, Roozbeh Kalantari, Ava Shahrokhabadi, Niloofar Jafari, Fatemeh Shahabinejad, Yasaman Maleki, Sina Montajeb, Roya Mehrpouya, Hadis Ahmadi, Bita Vazir, Farrokhreza Kabir, Abdul Rehman, Zahra Elmi, Pouneh Hajipour, Hesham R. El-Seedi, Awad A. Shehata, and Wolfgang Eisenreich contributed to data curation, formal analysis, investigation, methodology, resources, software, validation, writing–original draft, writing–review and editing. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.