West Nile Virus (WNV) is transmitted by mosquitoes as it infects animals as well as humans. Hence, it is dangerous as it belongs to the Flaviviridae family which comprises 75 different viruses’ species. The West Nile Virus is divided into the Japanese Sero-complex, which comprises other viruses like the St. Louis encephalitis virus (SLEV). The West Nile Virus infects birds, horses, as well as humans. However, it originally started in regions like Europe, Africa, the Middle East, and Asia. It caused mild fever in humans. However, in rare cases, it caused severe conditions such as encephalitis or paralysis which was spread by mosquito vectors [1-3]. WNV is one of the most widespread arboviruses, found extensively across Africa, the Middle East, parts of Europe, the former Soviet Union, South Asia, and Australia. Before the 1999 outbreak in New York City, it had not been detected in the Americas, but the exact means of its introduction to the United States remains unclear. Early genetic studies pointed to a Middle Eastern origin for the virus in North America; still, later research suggests that current strains in Europe and Israel may have originated from a common source, which is presumed to be North Africa [4].This study is considered as an examination of the West Nile virus issue in the Middle East through providing and integrating biological, epidemiological, clinical, and biosafety data through a One Health lens. This review also reports on the non-vector routes of transmission, evaluates the geographic distribution of the virus and its clinical manifestations in humans and animals, and looks for gaps in the current biosafety and control measures. For the purposes of encouraging early detection, halt epidemics, and enhance overall biosecurity readiness, a regionally coordinated single health surveillance and response architecture that integrates environmental, veterinary, and human monitoring systems is severely required. The assessment revealed that the current response to WNV is insufficient and too fragmented.

To guarantee openness and scientific integrity throughout this review process, a structured narrative review was prepared utilizing a methodical approach. The major scientific databases, such as PubMed, Scopus, Web of Science, and Google Scholar, were used in a formal literature search to find all published studies from 2000 to 2024 that either laid the groundwork for the field or were the most recent to be published on the subject.

Using Boolean operators (AND, OR), the search method narrowed the results by combining relevant terms and phrases such as "biosafety," "biosecurity," "biological risk management," "laboratory containment," "BSL requirements," "pathogen handling," and "regulatory frameworks.".

Peer-reviewed publications, official guidelines (e.g., WHO, FAO, EU, CDC), systematic reviews, and English-language regulatory documents that specifically addressed biosafety and biosecurity principles, laboratory standards, or biological risk management systems were all included in the inclusion criteria. The exclusion criteria included research unrelated to laboratory biosafety or biosecurity governance, non-peer-reviewed sources, opinion articles with no scientific basis, and duplicate publications.

A full-text examination of a few selected papers was carried out after titles and abstracts were initially screened for relevance. Definitions, legal frameworks, implementation tactics, and risk management concepts were the main topics of the thematic synthesis of the gathered material. After that, the results were arranged to give a logical summary of the standards, difficulties, and potential future paths in biosafety and biosecurity.

Like other Flaviviruses, WNV has a positive single-stranded RNA genome[5,6]. The C protein is important for viral replication due to interaction with E3 ligases such as HDM2 [7,8]. The prM protein has been thought to play a vital role in preventing the premature fusion of E-proteins with the host cell membrane [5]. As a transmembrane protein, the E protein plays a key role in maintaining the structural integrity of the viral envelope [9].

At the same time, non-structural protein 1 (NS1) has a significant role to play in the replication and evasion of the immune system [10]. As for the other non-structural protein 2A (NS2A), it’s an important factor in the replication process and modulation of host immune response [11,12]. NS2B and NS3 proteins perform a critical step in the viral replication by cutting or cleaving the flavivirus polyprotein in the onset of clinical infections [13]. NS3 also interacts with NTPase (an RNA helicase) which is critical for RNA replication and viral production; as a result, it has become a target for antiviral drugs because of its critical function in the life cycle of the virus [14,15]. Differently, the NS4A plays a vital role in the membrane remodeling induced by flavivirus infection supporting the viral replication, this occurs due to the reorganizing the ER membrane and interacting with other protein parts (i.e., NS1, NS4A, NS4B), disrupting the host immune response and enhancing the viral replication and immune suppression [16,17]. The NS5 is considered the most significant protein in flaviviruses [18], NS5 methyltransferase (MTase) allows the virus to escape the host's innate immune defenses, it also inhibits the translation of interferon-stimulated genes (ISGs) therefore enhancing the virus's ability to evade immune detection [1]. You can check a summary of the virus parts in Figure 1.

WNV begins with a mosquito bite, entering the skin and infecting local cells [19]. First, it binds to specific receptors on host cells and enters via clathrin-mediated endocytosis [20]. Fusion with the endosome releases viral RNA into the cytoplasm, which moves to the ER for translation within replication complexes that support viral assembly. After forming, immature virions bud into the ER and travel via the trans-Golgi network, where they are matured by furin cleavage and acidic conditions. Infectious virions are then released when vesicles merge with the plasma membrane[21-23]. It’s vital to mention that the Mosquitoes are the primary vectors and also act as intermediate hosts [24]. Refer to Figure 2 for an overview of the transmission cycle. Non-vector transmission occurs through organ transplants, needlestick injuries, hemodialysis, and blood transfusions from infected donors [26,27]. Transmission has also been observed in goose farms via contact with infected blood or tissues [28]. Although less common, these routes emphasize the importance of preventive measures.

WNV is primarily transmitted by Culex mosquitoes, which maintain the virus in bird populations. While other animals (e.g., elephants, rhinoceroses, lemurs) can be infected, only birds develop sufficient viral levels, making them key reservoirs and amplifiers that infect mosquitoes and indirectly humans and other mammals, which are dead-end hosts [1,29]. In addition to Culex mosquitoes, other species may act as WNV vectors, but their transmission efficiency is lower and typically limited to localized spread [30]. WNV is present in several Middle Eastern countries, including Israel, Turkey, Jordan, Iran, and Lebanon. In this region, transmission occurs through mosquito species such as Culex pipiens, Culex perexiguus, and Aedes caspius, which play key roles in spreading the virus among birds, humans, and other animals [31]. The four stages of development for Culex mosquitoes starts with egg, larva, pupa, and adults. The first three develop in water, and depending on the circumstances, it takes about 7–10 days to reach adulthood. In order to spread WNV, females lay 100–300 eggs on water. The larvae feed and molt, pupae grow, and adults emerge to seek out blood meals, frequently from birds. As dead-end hosts, humans do not spread the virus to mosquitoes[32,33]. Check the details in Figure 3 about the Culex mosquito lifecycle.

Infected mosquitoes transmit WNV through saliva into the skin, where it infects cells and spreads via lymph nodes. It can cause a variety of diseases in humans, with erythematous macules being the most common skin sign [35]. Clinical manifestations of WNV vary with host species, age, health, viral strain, and host–virus interactions [1]. In humans, early symptoms include fever (>38°C), headache, depression, altered mental state, and personality changes, sometimes with rashes, swollen lymph nodes, or enlarged liver/spleen. Children, the elderly, and those with chronic conditions are at higher risk. Meningoencephalitis may cause neck stiffness, photophobia, muscle weakness, or paralysis, while gastrointestinal involvement can lead to nausea, vomiting, and loss of appetite [36-38]. However, in susceptible avian species, signs include ruffled feathers, lethargy, ataxia, abnormal posture, flight difficulty, head tremors, seizures, paralysis, and nystagmus [39,40]. Table 1 shows further epidemiological details of West Nile virus integration in each host and the clinical manifestation that accompanies it.

West Nile virus (WNV) was first identified in Uganda’s West Nile district in 1937 and was isolated from a febrile woman from which the virus derives its name [46]; it had been present in Africa, the Middle East, and South Asia for over 60 years before it reached the Americas. Initially isolated from a person with mild illness, WNV was not linked to deaths in early outbreaks. Although its introduction to the Americas allowed researchers to track its spread, epidemics in Africa and surrounding regions were thought to have occurred before the recognition of clinical cases. A serosurvey in 1939-1940 revealed widespread human exposure to WNV in Uganda, Sudan, the Democratic Republic of Congo, and Kenya, with over 50% seropositivity in some areas. Additional seropositivity was later found in Nigeria, South Africa, and among various animals, indicating the virus had been circulating across much of Africa long before clinical cases were documented [47]. Table 2 displays cases from Middle Eastern countries with WNV-reported cases using clinical and experimental data.

Although Biosafety and biosecurity are connected, they operate separately under legal and regulatory frameworks as both are designed to ensure dangerous pathogens remain within designated areas but address different concerns. Biosafety is the collection of guidelines, procedures, and protective measures used in laboratory settings to minimize the risk of exposure to infectious agents and to prevent their accidental release, thereby safeguarding personnel and the community [74].on the other hand, Biosecurity is an integrated framework of policies and regulations aimed at managing risks to food safety, public health, animal and plant health, and the environment[75].Furthermore, surveillance programs of WNV are designed to monitor the spread of the virus from one vector to another, it involves testing the mosquito population for any WNV, monitoring dead birds, testing other animals like horses, and keeping track of human infections. The data is then analyzed to identify the areas where the virus is more prominent, as well as the success of control measures in them. All these activities are to ensure early detection and response to any possible outbreak, hence promoting public health [76]. Laboratories that study emerging pathogens are a growing global health concern, because even with risk awareness the workers there are still at high risk of infection if not being careful and strict. Their increasing number is a critical evidence for the need of strict adherence to biosafety measures to prevent and protect any lab-acquired infections or mistakes. Therefore, ensuring that only well-trained workers could deal with these pathogens and to recognize the risk of transmission is important, as well as having adequate facilities, procedures, and of course, waste management in labs to ensure the safety of both the workers and the public from any possible exposure [77,78].

It’s important to understand the biosafety levels as they rank from 1 to 4, corresponding to the increasing level of danger posed by the biological agents being handled. First, the BSL-1 as an elementary, posing little risk and it does not require specialized containment equipment but must implement basic safety measures; BSL-2 requires personal protective equipment and restricted access due to potential risks; BSL-3 involves high-risk agents, necessitating controlled environments and stringent safety procedures; and finally BSL-4, for the most hazardous agents which imposes strict safety protocols like the use of full-body protective suits and highly secure facilities [79,80]. The West Nile virus can cause severe and fatal diseases, and there are no treatments for such severe cases yet, most of the work with this virus was done in a biosafety level 3 environment. Its first recording dates to 1999 in the USA; recently, however, there has been a shift in the USA and the virus is now able to be handled at a lower biosafety level as it has become widespread and generally causes only mild symptoms [81]. Part of the safety measures for laboratory personnel working with WNV involve them wearing protective clothing, gloves, face shields, and gowns so as not to be exposed directly to infected samples. It is recommended to avoid contact between their skin or mucous membranes and any WNV, contaminated tissues or fluids, follow good sharps management procedures and dispose of biohazardous materials properly. It is also crucial that they wash their hands very well after taking off their protective gear and if possible, limit the production of aerosols during work; employers have to provide sufficient training and keep an eye on their employees for any signs of WNV exposure or symptoms of illness [82]. Some prevention paths focus on avoiding mosquito bites through repellents, protective clothing and/or reducing mosquito habitats. No specific antiviral treatments or vaccine are available in humans against WNV yet as most people recover without medical intervention, but those with severe symptoms (e.g., encephalitis or meningitis) often require hospitalization [76]. In some laboratories settings, a high-dose Ribavirin and interferon-α 2b have shown effectiveness against West Nile Virus (WNV) but no clinical trial evidence confirms their efficacy in humans. Most treatment is supportive, focusing on fluids, pain relief, and breathing support in severe cases. Complications and subsequent infections are additional potential healthcare needs for hospitalized patients .To reduce transmission, public health efforts target mosquito control through monitoring, insecticides, and eliminating standing water where they breed [83]. Recent research of four FDA-approved drugs: cilnidipine, mycophenolate mofetil, nitazoxanide, and teriflunomide, were effective against WNV infection in human cells significantly reduced the infection in Vero and human neuroblastoma SH-SY5Y cells; thus, nitazoxanide and teriflunomide demonstrated the highest potential, showing antiviral effects in both cell lines and protecting some mice from lethal infection challenges [42]. These findings mainly suggest their promise as treatments for WNV in humans although further clinical studies are required to confirm their safety, efficacy, and optimal therapeutic use.

Managing the virus effectively requires collaboration across all levels of government, including structured programs to monitor mosquito populations, track wildlife, and raise public awareness about disease risks. There are challenges to be addressed, including how to adapt to the endemic presence of the virus while adhering to international regulations. Although maintaining an updated surveillance system and implementing proper control measures is an ongoing need for the protection of public health against disease-causing agents[84], the implementation of biosafety and biosecurity is being hampered in the Middle East by limited infrastructure, political instability, and limited resources. Additionally, many countries do not have complete regulatory systems in place to adequately enforce safety measures and there are insufficient training or qualified personnel available for effectively managing biological risk, making certification of laboratory equipment difficult. These issues are further compounded by the presence of high-threat pathogens coupled with a need for improved control mechanisms [57,85].

The One Health concept highlights the mutual dependence of environmental, animal, and human health, particularly with regard to zoonotic illnesses like WNV. It involves coordinated surveillance systems that track the virus by testing mosquitoes, monitoring bird populations (the main reservoirs), and observing human cases to better understand its spread. Since WNV mainly circulates between birds and mosquitoes, with humans and other animals as incidental hosts, this approach emphasizes collaboration in surveillance, vector control, and vaccination efforts [76]. Please refer to Figure 4 for a visual summary of One Health Approach.

Monitoring is essential for the early identification and management of WNV epidemics. By integrating data from humans, mosquitoes, birds, and other animals, reactions may be made more quickly, protecting people by seeing threats before the virus spreads [76,84]. For example, countries can implement bird and mosquito testing alongside human clinical monitoring and weather change through the One Health approach since it can favor the mosquito vector population, providing comprehensive insight into WNV transmission dynamics [86]. There is no available WNV vaccine for humans, but developing an effective vaccine remains a high priority. Under a One Health framework, the strategy for vaccine deployment could initially focus on equine populations and other susceptible species to WNV and serve as sentinels in some cases [34]. Vaccinating horses could reduce the incidence of disease in animals and potentially lower the overall viral burden in areas where both human and animal transmission risks are high, as evidenced in studies conducted in the United States of America (USA) [87]. Also, effective mosquito control measures, including habitat management, insecticide application, and community engagement, reduce WNV vectors' prevalence in urban and rural areas [88]. Finally, collaborative research and policies across countries could enhance preparedness and response to WNV, cross-border data sharing and collaborative policy-making, which is essential in regions where migratory bird patterns can spread WNV across national borders, as suggested in Europe [34]. In Middle Eastern cases, many countries have plans to go against WNV. For example, Egypt plans to improve its communication locally and globally to identify pathogens and infections around the country; Turkey focused on the vulnerable target group of agriculture workers when no other country-specific risk group for the virus, and occupied Palestine aims to improve vector management regulations regarding environmental changes [89].

There are many interventions that could enhance WNV management and control in the Middle East. To strengthen the One Health approach, it is crucial to advance beyond informal agreements by establishing a formal governance architecture with a supporting legal framework that institutionalizes collaboration between human, animal, and environmental sectors. To guarantee a truly coordinated response, this structure should be backed by a specialized regional workforce or technical body in charge of managing shared data platforms, standardizing standards, and increasing capacity. Proactive risk communication and community involvement should also be part of the strategy for the purpose of making the public active participants in surveillance and prevention. This strategy creates a more robust and long-lasting defense against zoonotic diseases like the West Nile Virus[90]. Implementing a One Health framework in the Middle East based on the Italian model that was proposed to evaluate the extent of the One Health implementation in Italy, the region should first establish a cross-border committee with representatives from public health, veterinary, and environmental sectors to define unified surveillance goals for West Nile Virus. Addressing the communication and learning gaps that the Italian research highlighted as problems quickly, it must next establish a centralized data-sharing platform and standardized training programs. To ensure continuous improvement, this new framework should be periodically evaluated using the same quantitative "One Health-ness" scoring method, allowing leaders to systematically identify and strengthen the weakest parts of their integrated strategy[91]. As the Centers for Disease Control and Prevention (CDC) advises, the construction of an integrated strategy for West Nile Virus based on a staged response plan should incorporate the appropriate actions to be taken depending on the level of risk. Initially, complete and integrated surveillance systems should actively monitor mosquito populations, as well as wildlife populations, (species of birds in particular via carcass reporting) and horses, thereby providing information on the presence of the virus before humans become infected. As the likelihood of an epidemic rises, changes in environmental surveillance should lead to additional vector control activities such as controlling the habitats of vector developing (e.g., controlling larval habitats) and applying larvicides/adulticides as appropriate. Crucially, this tiered response must be supported by a strong public communication and community engagement program that educates on personal protection, encourages residential source reduction, and clearly communicates the reasons behind any emergency control operations .

In the Middle East, the West Nile virus (WNV) is a chronic but little-known public health threat. It is produced by complex interactions between mosquito vectors, bird reservoirs, environmental variables, and human populations. Despite increasing evidence of ongoing viral circulation and variable seroprevalence rates in both humans and animals, regional preparedness remains fragmented. This is largely due to significant gaps in diagnostic capacity, vector surveillance, and biosafety infrastructure, which weaken early detection and response efforts.

This review argues that the absence of a coordinated One Health framework is a critical vulnerability. Therefore, establishing a regionally integrated strategy is essential for strengthening preparedness. A central priority should be integrated surveillance systems that simultaneously monitor human infections, animal hosts, and mosquito populations to enable early detection. This must be coupled with an expansion of laboratory capacity and biosafety governance, including improved BSL-2/BSL-3 infrastructure and harmonized regulatory standards. At the policy level, sustainable vector control programs and enhanced regional cooperation—through joint surveillance platforms and coordinated response mechanisms among Ministries of Health, Agriculture, and Environment—are critical to addressing the transboundary nature of WNV and transforming fragmented national responses into a unified, effective regional strategy.