Despite advances in the detection and control of infectious diseases, many new infections are emerging and re-emerging globally, including avian influenza viruses H5N1 and H7N9, Middle East Respiratory Syndrome coronavirus (MERS-CoV), severe acute respiratory syndrome coronavirus 1 (SARS-CoV1), and, more recently, severe acute respiratory syndrome coronavirus 2 (SARS-CoV2). The consequences of these emerging infections may be catastrophic, as people have very little or no immunity against these pathogens. Moreover, some existing infections are emerging in new geographical areas or have seen increased incidences recently; these include Ebola, monkeypox, West Nile virus (WNV), dengue, chikungunya, and Zika (1–3). Most of the emerging and re-emerging infections are of zoonotic origin, which highlights the importance of controlling these diseases not only in humans but also in animals (4). Vector-borne diseases (VBDs) are also a major public health issue and more than 80% of the world’s population is at risk of developing one or more VBDs (5). Important factors contributing to the emergence and re-emergence of these zoonotic and vector-borne diseases include changes in human habitat and climate due to urbanization, deforestation, and reforestation; changes in food production and farming practices; increased poultry density and more frequent contact with animals; and an increase in travel, trade, and tourism (1, 6–8).

The Eastern Mediterranean Region (EMR) of the World Health Organization (WHO) is sociopolitically diverse and includes countries from the Middle East, North Africa, the Horn of Africa, and Central Asia (9). The emergence risk of zoonotic and vector-borne diseases is high in this region due to its topography, complicated geopolitical situation, mass gatherings for religious and sporting events, and other socioeconomic factors (10–12). Four of the eight migratory birds’ flyways pass through various countries of the EMR: Central Asia–India, East Atlantic, Mediterranean–Black Sea, and West Asia–Africa (13). These migratory wild birds are reservoirs for many avian influenza viruses and may transfer viruses to domestic birds, poultry, and subsequently, to humans as well. Climate change and other environmental factors also affect the survival and distribution of high-risk pathogens and their vectors and hosts. The complicated geopolitical situation and humanitarian emergencies have also resulted in the spread of infections due to huge population displacement, interruptions in health services, poor living conditions, weak surveillance and disease-detection capacities, and the lack of disease control measures (10).

Over the last few decades, at least 11 countries in the EMR have reported major outbreaks and epidemics of zoonotic and vector-borne diseases, which have had the potential to spread globally ( Table 1 ) (14). Currently, there are approximately 50 active outbreaks ongoing in the region, with 70% of them related to vector-borne and zoonotic diseases. Avian influenza A (H5N1) and MERS-CoV are considered two of the greatest threats to global health security and both viruses are endemic in the EMR. Sporadic cases and outbreaks of monkeypox, sandfly fever, Alkhurma hemorrhagic fever (AHF) (20–22), and plague are also occurring in a few countries, but there is limited information on other rare zoonotic diseases such as Q fever, and tularemia (23). In addition to these outbreaks and epidemics, many zoonotic and vector-borne infections are endemic in the region, such as rabies, brucellosis, leishmaniases, Ebola, other food-borne zoonotic infections, and malaria.

Despite many challenges, countries in the EMR have made significant progress toward the control of zoonotic and vector-borne diseases in recent years. Prevention, preparedness, and response capacities to emerging and re-emerging zoonotic and vector-borne diseases have been improved. IHR (2005) core capacities have been strengthened and 17 countries in the region have completed joint external evaluations of IHR (2005) capacities (62, 63). Surveillance systems have been improved and 19 out of 22 countries have sentinel surveillance to collect and analyze data on severe acute respiratory infections (SARIs) and influenza-like illnesses (ILIs) (64). After the emergence of avian influenza virus A (H5N1) in Egypt, the Eastern Mediterranean Acute Respiratory Infection Surveillance (EMARIS) network was established in the region to improve SARI and ILI surveillance and to strengthen countries’ capacities to detect seasonal and new influenza viruses (65, 66). Moreover, the Early Warning Alert and Response Network (EWARN) has been introduced in many countries facing humanitarian emergencies. The laboratory diagnosis capacity for emerging and re-emerging infectious diseases has been enhanced across the region, with more reference laboratories with adequate capacity being built. The Emerging and Dangerous Pathogen Laboratory Network (EDPLN) has also expanded (67). In January 2020, only four countries in the region had the laboratory capacity to test for COVID-19. By mid-February that same year, however, with the support of the WHO and partners, all 22 Member States had built laboratories with the capacity to conduct COVID-19 reverse transcription-polymerase chain reaction (RT-PCR) testing in 2021 (68). By late 2022, with the support of the WHO and partners, 21 Member States could carry out domestic COVID-19 genome sequencing.

Similarly, outbreak response capacity has been improved and most countries in the region have trained rapid response teams at the central level to investigate outbreaks due to emerging and re-emerging pathogens (64). Training has been provided on surveillance, field investigation, and diagnosis. Many new activities were initiated to control the Aedes mosquito in the region, which is the primary vector for many emerging and re-emerging VBDs. The WHO EMRO has also developed a framework for a One Health approach, although the coordination mechanism between human and animal health sectors is still weak in most countries in the region (69). Various activities are ongoing in the region to prevent outbreaks during events with mass gatherings, such as risk assessments, strengthened surveillance and case detection/reporting, case management training, laboratory capacity scale-up, vaccination against common infection, increased awareness, and rapid response. The WHO EMRO has also developed a strategic framework for the prevention and control of emerging and epidemic-prone diseases in the region, with the goal of reducing the burden of emerging and epidemic-prone zoonotic and vector-borne infectious diseases in the WHO Eastern Mediterranean Region by 2024 (70). Countries in other WHO regions may also adopt some of these strategies in a local context to control zoonotic and vector-borne diseases.

Owing to these initiatives, a number of outbreaks of emerging infectious diseases have been successfully contained in the region. The lessons learned from these outbreaks were leveraged to manage the COVID-19 pandemic in several countries. For example, surveillance systems, laboratories, infection prevention and control measures, and clinical care networks for endemic diseases were rapidly utilized during the early phase of the COVID-19 pandemic. Guidelines, policy documents, training modules, standard operating procedures, risk assessment tools, and checklists developed for MERS-CoV and other emerging and re-emerging diseases were used to inform initial technical guidance documents and information products for COVID-19. Similarly, standardized seroepidemiological protocols developed for other emerging and re-emerging infections were quickly adapted for COVID-19 and were implemented across many countries in the region to rapidly identify key epidemiologic parameters of SARS-CoV-2, and also to understand the nature of the infection, the extent of its spread, and risk factors. Reference laboratories in high-resource countries in the region were leveraged, particularly in the early stages of the pandemic, to provide laboratory support and confirmatory testing for affected countries.

There are many challenges associated with the control of zoonotic and vector-borne diseases in the EMR, most of which are also common in other WHO regions, such as increased population movement, the unavailability of vaccines and specific treatments for many zoonotic and vector-borne diseases, and zoonotic spillover. The challenges specific to the EMR are highlighted in Table 2 . Some important challenges, particularly in countries experiencing humanitarian emergencies, are weak detection and response capacities, poor animal source/vector control measures, fragile health systems, the lack of resources, competing priorities, and the unavailability of drugs and vaccines (61). Countries need to address these challenges to control emerging and re-emerging zoonotic and vector-borne diseases and to prevent morbidity and mortality, particularly among vulnerable groups. Table 2 also contains some strategies to address these challenges in the EMR countries and countries in other regions in similar circumstances. These strategies are in line with the WHO strategy for the Eastern Mediterranean Region, 2020–2023 (68), and the strategic framework for the prevention and control of emerging and epidemic-prone infectious diseases in the Eastern Mediterranean Region (70).

In summary, the incidence of many zoonotic and vector-borne diseases is expected to increase in the future due to climate change, globalization, urbanization, and other factors (74). Therefore, countries should focus on strengthening their capacities to prevent, detect, and respond to outbreaks due to these diseases. Surveillance systems should be strengthened, incorporating an early-warning component for rapid detection and response to outbreaks due to zoonotic and vector-borne diseases. The IHR (2005) should be the key driver for rapid epidemic intelligence and global health security. There is a need to improve laboratory capacities for the timely and accurate detection of emerging pathogens, including point-of-care testing, with implications for regional and global health security.

The majority of zoonotic and vector-borne diseases spread due to close contact with animal hosts or vectors; therefore, countries should foster effective collaboration between the animal, human, and environmental health sectors to prevent the emergence and spread of these diseases. Intersectoral collaboration and coordination are important for the timely sharing of epidemiological and laboratory surveillance data and for exercising integrated responses. To achieve this, the One Health approach should be adopted and a system should be in place to oversee all One Health activities, including governance, policy and legislative frameworks, advocacy and communication, collaboration among various sectors, training and capacity building, data sharing, integrated surveillance and response systems, research, and monitoring and evaluation (75, 76). Countries in the EMR are at different stage of implementing the One Health framework. Countries without One Health initiatives in place should develop a national strategy and operational plan in consultation with relevant stakeholders, endorsed by relevant ministries. Countries with existing One Health plans should enhance their key activities, such as risk assessment, prioritization of zoonotic diseases, preparedness and response activities, assessment of existing capacities, identification of research priorities, and coordination with partners (75). Many countries in the region may lack the capacity to implement the One Health approach, thus international organizations, non-governmental organizations, academic institutes, and private sectors can be engaged (76).

Response capacity should also be strengthened to contain outbreaks of zoonotic and vector-borne diseases early; otherwise, they may cause significant morbidity and mortality. Tailored strategies should be developed for countries experiencing humanitarian emergencies, as in addition to poor surveillance and testing capacities, these countries do not have adequate healthcare infrastructure and basic healthcare services such as immunization against common diseases. Therefore, rapid detection of and response to epidemics should be a high priority among affected populations. Finally, as there is limited information on the burdens, trends, and risks of zoonotic and vector-borne diseases in the region, more research is needed.

Publicly available data sets were analyzed in this study. These data can be found here: https://www.emro.who.int/entity/about-us/index.html.

AC prepared the first draft of the manuscript. CK, MT, and MP provided data from regional offices and reviewed the manuscript; RJ and AA reviewed the manuscript and gave critical input. All authors approved the final version.