Effects of Climate Change on Epidemic Propagation and Community Preparedness: A Review

Abstract

Climate change is the twenty-first-century driver of global epidemic outbreak distribution. An early warning system for effective community preparedness is the antidote if the SDGs will not be a mirage. This study review adopted the search engine secondary method of data collection and descriptive content analysis in conjunction with the other in-depth interview survey reported by recent studies on climate change-induced health challenges and opinion survey on community participation in disease monitoring and control. Proper grassroots dissemination of climate change reality and the attendant intrusion of new diseases that are not amenable to existing medical and tradomedical approaches are imperative, hence the need for contingency planning by all the stakeholders. There is also the need to adopt real-time geospatial analysis techniques and environmental safeguard policy at all levels for disease monitoring and disseminating information to relevant policy makers and implementing agencies.

1. Introduction

The issue of an epidemic outbreak is not new to the human race globally, while the phrase climate change has also become a domiciliary word, and even though the scientific definition seems even milder, its impacts across the world are disastrous, alarming, becoming frightening as its episodes are threatening the continuous existence of human race. Scientific research on its atmospheric variation over the past 50 years has shown a steady increase in atmospheric carbon dioxide (CO₂) due to anthropogenic activities. The observable verifications soar if the projected climate variables go above the bounds for which a country’s operation is patterned. In that case, the least desirable environmental cataclysm demanding management and adaption will erupt [1]. The only problematic and shocking about the whole issue is the convincing assurance that anthropogenic phenomena warm and change the atmosphere more than any recorded modern history [2]. In fact, oxidized gases like nitrous oxide (N₂O) and even halocarbons have been substituted continually for chlorofluorocarbons (CFCs) in refrigerants in the atmosphere [3]. Regrettably, the agricultural sector happens to be one of the culprits that also exacerbates the GHG that propagates a series of epidemiologies in the face of resilient and unsustainable community health security across developing countries and sub-Saharan countries in particular. Hence, the need for the development of integrated global, national and community preparedness as advocated for by the WHO in the COVID-19 pandemic.

2. Review of literature

2.1 Concept of climate change and global warming

Climate change can be seen as the deviations that occur in the already established knowledge of the atmospheric condition of places over two to three decades. Researchers often use statistical approaches to ascertain whether changes in climate are not probably within the range of natural adjustment and mere coincidental; since the probability that the increase in atmospheric warming since 1950 is not occasioned by natural forces is less than one percent (1%). Climate change can be seen as a momentous long-range modification of the global climate as it relates to the interconnected system of the wind, sun, ocean, precipitations, general terrain and anthropogenic activities. The analysis of the global climate can be addressed using the cybernetics system-of-system approach, where the whole globe is seen as a single system. A change in the Land Surface Temperature (LST) in Yucon Territory that led to the glacial melting will eventually affect the Atlantic Ocean tidal rise and tsunami activities in the southern hemisphere. Again, the industrialization and over-dependence on fossil fuel of EU and USA is the bane of climate change and its attendant natural disaster in Africa and other developing countries.

Climate variability connotes a planetary system capricious in a climate that ranges in months and decades. Climate variability occasioned by the activities of atmospheric get streams like the inter tropical convergence zone (ITCZ) in the tropics and the El-Nino in regions of the world for more than 2 years are significant natural climate anomalies. Anthropologist, Biodiversity Conventions, and Sustainable Eco-developments uses global ecological services (ES) maps to assess the global trends of ecological variability for SDG policy formation. The proposition that there are no climate change occurrences may be difficult to stand amidst myriad avalanche visual and sensor-based evidence data on heat waves, dwindling ice cap and tsunamis across the world. Global warming is the continuous slow increase in the average temperature of the earth’s atmosphere as a result of the increase trapping of the re-radiated energy (heat) emitted by the earth from the incoming sun radiant energy. The re-radiated and emitted heat does not get to the outer space but trapped at the lower altitude. The excess greenhouse gas as a result of anthropogenic activities now trapped more than required surface temperature for the sustenance of life forms including humans, (see Figures 1 and 2).

Figure 1.

Global land-ocean temperature index and greenhouse effect (Source: NASA and Center for Climate and Energy Solutions).

Figure 2.

Global land-ocean temperature index and greenhouse effect (Source: NASA and Center for Climate and Energy Solutions).

Heat is energy and when added to the global climate systems that are interconnected, changes occur. And since two-thirds of the earth’s surface is covered with ocean, it gets heated up, leading to much evapotranspiration. Also, intensive-energy storms like typhoons, tornadoes, hurricanes, and cyclones are on the increase globally, while the Arctic and Antarctica ice-caps are fast striking in coverage. All these directly lead to global ecological modification and migrations of multivariate disease vectors, as reported by many studies [4, 5, 6, 7]. The geographical temperature, rainfall and humidity distribution dynamics and population dynamics are closely related to the patterns of – insect vectors metabolism and migratory activities globally. Even Measles epidemics, for example, that are cyclic, recurring whenever the proportion of susceptible individuals reaches a suitable threshold, are temperature-related.

2.2 The concept of InVEST and disease control

Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) is an integrated software package for mapping and valuing nature goods and services that sustain human existence., and it is a tool initially developed by the Natural Capital Project [8] to demonstrate ecosystem productivity function at a given place and time. InVEST has been used in Baoxing County by the Chinese local government to integrate ecosystem services into their Land Use Master Plan with better results than past projects. The tool helps evaluate the impacts of ecosystems modification, leading to dwindling in ecosystem service provision to people or as a seascape [9]. The models explained both service provision types, activities locations and the beneficiaries. A change in climate invariably modifies the functionality of local biotic microorganisms that are made to relocate while new ones replace them forcefully, hence the invasion of seemingly strange microorganisms and diseases.

2.3 The concept of EMP and ESG and epidemic control

An Environmental Management Plan (EMP) is a planning approach that accounts for a specific environmental monitoring statement comprising measured variables, sampling locations, threshold tolerances and remediation. In epidemic monitoring and surveillance, there is the need to watch the atmospheric pollutant tolerance level benchmarked in the Kyoto Protocol to the United Nations Framework Convention on Climate Change (UNFCCC), including even hydrofluorocarbons (HFCs), per-fluorocarbons (PFCs), and Sulfur hexafluoride (SF6). Ecological balances in both climatic variables and the food chain require the strategic implementation of environmental management, mitigation measures, monitoring programs, cost estimates, resource requirements, budget and institutional arrangements. The creation of new and dynamic ecological niches that favor certain microbe and the emergence of certain signals are what epidemiologists should look for in any given locality. This is where early warning signals comes from, and professional in that area of specialty are to disseminate the warning to the relevant agency for policy formation.

2.4 Critical habitats and epidemiology control

The doctrine of critical habitat is very jamming in epidemiological control as it relates to critical specific ecological locations with huge biodiversity functional value to the community. They include habitats with endangered, endemic resistive range species sites and ecological convergence zones of evolutionary processes with relevant socioeconomic or cultural values to the community or the nation.

Significant conversion or degraded ecology may be in the form of (i) acute shrinking of habitat functionality caused by natural or human-induced land use changes or (ii) critical change in the habitat food chain that endangers the existence of some native species. This is the basis for the invasion of alien species that are non-native to existing flora and fauna, which significantly thread the biodiversity due to their ability to spread rapidly and out-compete native species. Transboundary impacts of biodiversity distortions are impacts that extend to multiple countries beyond the host country but may not be global in nature.

Plants were the first known hosts for viruses, and plant viruses have been a focus of research over the years when viruses were more ecological in nature, and most of the work done in plant virology has been molecular [10]. But of late, rodents are known as hosts to many viruses that are inimical to human health, while unique habitat distortions and species niche expurgation have been associated with the emergence of zoonotic diseases [11].

For instance, Ebola is transmitted into the human body system through contact with blood, secretions, or other bodily fluids of host animals such as fruit bats, monkeys and forest antelope in the rainforest. It was first observed in 1976 in Nzara, South Sudan, and in Yambuku, Democratic Republic of the Congo, near the Ebola River. The forest fruit bats of the Pteropodidae family were thought to be the natural Ebola virus hosts.

Zoonotic disease studies on the post-West African Ebola Virus Disease (WAEVD) outbreak reveals that changes in land uses and vegetative cover are a significant contributing factor to emerging infectious diseases (EIDs). The general idea is that zoonosis occurs when there is an interface between at least one pathogen and two host species, which may be human and another host animal species, as illustrated in Figure 3. In fact, for many centuries, Zoonoses have been acknowledged, and over 200 cases have been diagnosed including Ebola, SARS and HIV [12, 13].

Figure 3.

Ebola and other virus zoonosis cycle (Source: Modified after Centres for Disease Control (CDC)).

As inner core forest-dependent bat species lose habitat, they migrated to the secondary human-modified landscape in search for new habitats and food in already almost bat saturated areas. When a particular environmental stresses such as; reduced food and nutrition, extreme weather conditions, reduced shelter, and increased competition, there will be compromised immunological systems in wildlife and humans. There is therefore the need to carry out community safety advocacy on major development in any community.

2.5 Environmental safe guards (ESG) and indigenous peoples

Community health and safety refers to all conscious efforts in protecting and safeguarding the local communities from the adverse effects of developmental project-related hazards emanating from ecological transformation and curtailing the spread of communicable diseases from workforce to the host communities. Major construction sites during or after decommissioning are potential sources of biohazards in the form of communicable diseases like HIV/AIDS and bilharzias. The present climate change push factors have led to global and regional migration of workers in search of juicy jobs, but are host to malaria parasites like Sika that may overwhelm local resilient levels. Proper monitoring and management of health and safety impacts of major projects will help in creating positive community environmental perception and preparedness. This is where the principle of inclusive planning becomes relevant in policy formation and implementation. Large projects that will significantly affect the ecological setting of a locality must be participatory, and there must be robust contingency planning in place for effective sustainability and disease surveillance.

Key aspects of protecting local communities from project-related disease hazards are summarized below:

1. Assess the weather-related changes and identify disease-related vectors and potential impacts on the safety of the communities.

2. Establish mitigation and adaptation strategies that are commensurate with the perceived risks, hazards, and propagation. These approaches should strengthen the community resilience level far beyond their hitherto vulnerability levels.

3. Conduct an assessment of the Vulnerability and Capacity Analysis of the community and the levels of their exposure to weather related hazards.

4. Manage vector habitats to avoid or minimize the exacerbation of impacts caused by them on the environment such as water bodies and drought that could result from significant changes to vegetation cover, topography, and hydrologic regimes

5. Have community-based emergency prevention, preparedness, and response arrangements in place if the consequences of emergency events are imminent with local authorities, and focus on the following:

   1. Define specific emergency response procedures.

   2. Trained emergency response teams.

   3. Define emergency contacts and communication systems/protocols.

   4. Establish integration of local and regional emergency and health authorities.

   5. Permanently stationed emergency equipment.

   6. Define protocols for ambulance and other emergency vehicle services.

   7. Designate evacuation routes and meeting points.

   8. Conduct drills (annual or more frequently as necessary).

Going by the dynamic terrain of the global ecological system as a result of human-induced climate change variability and the increasing challenges of exotic pathogens [14], Various rubrics models of integrated risk-based, disease-targeted surveillance and participatory surveillance have emerged in response to the global pandemic phases [15, 16, 17]. Therefore, much of such models focus on both veterinary and human epidemiology that are technically associated with risk and risk factors that border on how to better account for disease propagation.

3. Methodological approach

The study adopted the search engine secondary method of data collection and descriptive content analysis in conjunction with the other in-depth interview survey reported by recent studies on climate change-induced health challenges and opinion survey on community participation in disease monitoring and control and Non-governmental interventions. Major deduction was made toward achieving the sustainable development goals (SDGs) targets 3 and 13 that address good health and well-being; and Climate action in the country.

4. Discussion

4.1 Global diseases weather tolerance distribution

Generally, many scientists have jettisoned what was once a basic preposition in infectious disease modeling: that a vector’s ability to flourish and infest communities has a direct linear relationship with increasing temperature. While the nonlinear models explained the relationship between warming and propagation within a range of time and place better. Excessive heat beyond the tolerance levels of vectors and pathogens do slow down transmission thereby leading to decline in disease spread. Studies have revealed that many mosquito-borne viruses get to the topmost between the range of 23°C and 26°C before dropping as temperature increases especially in the West Nile [18, 19, 20, 21, 22]. While hitherto cool, higher elevated areas that attenuated their propagation can become vulnerable with increased temperature; see Figure 4 for the global spatial coverage of malaria outbreak.

Figure 4.

Worldwide distribution of Malaria outbreak in 2019 (Source: WHO).

Also, according to Marcia Castro, Professor of Demography and chair of the Department of Global Health and Population at the Harvard T.H. Chan School of Public Health, malaria transmission in the highlands that are hitherto cool will increase over time and will become more susceptible to the mosquito vector staying longer than just a few months due to the influence of climate change. Warming weather generally catalyzes tropical disease pathogen propagation like the Zika virus in the Aedes aegypti mosquito that now migrated from Africa/Asia eastward to the Pacific since the year 2007, with more than 80 reported cases from other countries. For instance, in 2015, about 1.5 million people were infected in Brazil before spreading elsewhere in America. In fact, another modeling study has postulated that in a worst-case scenario, 1.3 billion more people will be living in locations with temperatures that are conducive for Zika transmission by 2050.

The Centre for Disease Control (CDC) approximated the number of Lyme cases treated in the United States at about 476,000 per year on average between 2010 and 2018, a significant increase above the annual average of 329,000 reported by the insurance claims between 2005 and 2010. This increase is in consonant with the increase in the spatial distribution of Lyme-bearing ticks and other diseases.

Infectious diseases caused by pathogen that develops in the environment or in an intermediate host are significantly influenced by climatic parameters that often have a direct association with the growth of the pathogens as their incubation can be aborted under unfavorable temperature; where, for instance, 18°C is the temperature tolerance for tropical Plasmodium falciparum and 20°C is for the Japanese encephalitis virus to increase reproduction rate [23, 24]. Climate change has therefore created a conducive habitat for the lone star tick, a vector for ehrlichiosis to thrive in New England that was initially limited to the southern United States.

4.2 Pathogenic habitat analysis

Globally, the significant consequences of the continuous spread of vector-borne infectious diseases where West Nile fever is now a common mosquito-borne ailment in the United States since 1999, along with other pathogens like Dengue and Chikungunya spreading into Europe as well. Critical aspects of a vector’s lifecycle, such as its growth, reproductive capacity, and biting rates, are temperature dependent, and for Sam Telford, professor of infectious disease and global health at the Cummings School of Veterinary Medicine at Tufts University, “drought is death,” for those vectors.

Diseases spread are generally associated with the environmental factors and biophysical state of a given locality. For example, temperature surges often force communities to be exposed to unwholesome water sources that can cause water-borne diseases, especially in arid and semi-arid regions [25]. A high rate of humidity prevents the body from sweating, resulting in fungal skin diseases, but modern advances in Remote Sensing and GIS have significantly assisted in comprehending the relationships between disease dispersal and geospatial dynamics as a complement to disease location and outbreak forecasting [26]. Real-time information on environmental factors has been veritable in identifying the habitats of disease vectors based on their ecology and the terrain configuration together with the land use/land cover dynamics. Geospatial analyses are significant veritable tools in understanding the relationship between disease dispersion and environmental factors, in addition to locating and forecasting outbreaks of diseases [26, 27].

Under the [28] survey program, it was found that about 8 in every 10 directors of local health acknowledged the existence of climate change, but less than 5% of health departments organizing climate change impacts education in their area. Also, only about 8.4% have adequate resources for residents’ protection against climate impact-related ailments. Although about 6 out of every 10 Americans are aware of climate change, this gap is a major challenge that calls for more innovative, cost-effective collaborations within local communities on early warning and preparedness.

4.3 Epidemiology monitoring and early warning systems

Monitoring and surveillance is used interchangeably in this context meaning a systematic continuous process of watching, collection of data, analyzing, interpretation, and dissemination of relevant results output on the latent health challenges for policy formation and implementation. Such result output should be disseminated to all the relevant stakeholders for effective disease prevention and control [29]. Historically, infectious diseases predicting outbreaks based on climate data can be traced to the work of Gill and Roger [30, 31] who developed an early warning system for malaria based on rainfall in India. Their approach demonstrated how an early warning system could be developed from weather variables like temperature, rainfall, humidity and winds for the incidence of diseases such as pneumonia, smallpox, leprosy and tuberculosis (TB). Presently, there exist myriad earth resources data from space-borne satellites and ground-based sensors that are easily accessible at relatively low cost, enhancing the assessment of the correlation of climate-related disease outbreaks. More so, advances in epidemiological and statistical modeling have allowed apparent associations to be tested explicitly.

Surveillance generally requires coordinated networks of relevant actors, free flow of information for disease prevention activities, control measures and epidemiological investigations. In fact, it requires contingency planning in which scenarios for tactical operations are established in relation to the dynamic environmental factors on a continuous basis from the local to the international, which may follow a cyclic process as in Figure 5.

Figure 5.

A conceptual basis for disease monitoring as a self-correcting cycle.

While monitoring, according to Akhtar and White [32], is the supervision of the occurrences of specific or general health events overtime within a given community which is the most common objective of surveillance. According to them, data from the system can be used to compute the incidences and prevalence of those health events. Surveillance objectives will generally include the following:

1. monitoring the trend of health events,

2. supplying researchers with trending issues,

3. appraise the effectiveness interventions,

4. predict trends of future disease,

5. disseminates real-time information on health issues to policymakers,

6. awaken the need for the integration of health stakeholders

Early warning is wide and multistage in approach involving many actors from the grassroots to complex digital simulation models. It always involves active engagement in crisis prevention, and the first approach is the prediction of when, why, where, and how epidemic crises will emerge. It is the act of troubleshooting latent problem in a community, the cause, how eminent, and the way forward. Early warning deals with the origin and the causes that empower community preparedness and not the symptoms. Early warning should be near real-time evaluation mechanism of risky phenomena in a highly vulnerable community that are likely to accelerate or trigger epidemic outbreak that is embedded in the UN Humanitarian Early Warning System (HEWS).

Quantitative Early Warning System (QnEWS), as against qualitative Early Warning System, employs systematic collection and processing of empirical information according to a given set of criteria with the aim of isolating the factors that contribute or influence the outbreak of problems, and ascertain the antecedent contextual structures, events and processes that can cause the outbreak of epidemic or violence using threshold patterns, causal or procedural model [33]. An early warning system such as in Figure 6 can be developed for an infectious disease only if the disease is epidemic-prone.

Figure 6.

Framework for developing early warning systems for climate-sensitive diseases (Source: After WHO [34]).

5. Conclusion and recommendation

Anthropogenic activities have negatively impacted the finite Mother Earth, thereby threatening the existence of man. The Ozone layer depletion directly impacts human health through climatic extremes, heat waves, air pollution, sea-level rise, drought, global epidemic, socioeconomic and political conflicts and food insecurity. The emergence of strange epidemic disease is the most devastating as it is boundary-less, and rendering existing innovations obsolete. The devastating impact of infectious diseases on human health and livelihood is intrinsically linked to complex stressors or drivers such as poor access to clean water and food, inadequate public health infrastructure and services, political instability and conflicts, drug resistance virus mutations, and population upsurge [See 35, 36]. The modification of vector–pathogen habitats has now led to epidemic disease dynamism in the twenty-first century. The world has experienced cases of SARX variants, HIV, Ebola, Lassa fever, ZIKV, COVID-19, etc., which raises the question “Who-is-free,” or “Are-we-ready.” The time to re-strategize and embrace integrated disease is now.

The following are therefore recommendations as a way forward;

1. The law of polluters pay should be vigorously applies at the international and national level as this will check the activities of those countries that pay lip service to eco-friendly development.

2. Contingency planning should be incorporated and implemented at all levels of health service delivery in the face of dynamic migrating Virus-Borne diseases (VBD).

3. Inclusive planning in the spirit of ‘leave-no-one-behind’ of the SDGs target should be fully advocated at all levels for local community capacity development and preparedness as emphasized in [37].

4. Policy on ecological preservation/conservation should be a priority at every governmental level, while encouraging all forms of eco-developments, [see 38].

5. Real-time geospatial analysis technology should be embraced at all levels for disease monitoring and dissemination of information to relevant policymakers and implementing agencies [as in 39].

6. COP-28 and other subsequent ones should create a session on climate change and epidemic diseases across the globe.