Volume 8 • Issue 10 • 1000418 J Earth Sci Clim Change, an open access journal ISSN: 2157-7617 Research Article Open Access Agan, J Earth Sci Clim Change 2017, 8:10 DOI: 10.4172/2157-7617.1000418 Research Article Open Access Journal of Earth Science & Climatic Change J o u r n a l o f E a r t h S c i e n c e & C l i m a t i c C h a n g e ISSN: 2157-7617 *Corresponding author: Peter Nkashi Agan, Department of Geography, University of Ibadan, Ibadan, Oyo State, Nigeria, Tel: 2348166207854; E-mail: aganpee@gmail.com Received August 02, 2017; Accepted October 20, 2017; Published October 27, 2017 Citation: Agan PN (2017) Heat Waves Research and Impacts on Human Health: The Need for Studies in Nigeria: A Review. J Earth Sci Clim Change 8: 418. doi: 10.4172/2157-7617.1000418 Copyright: © 2017 Agan PN. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Keywords: Hot waves; Heat island efects; Health Introduction Heat waves Heat waves refer to a run of hot days; precisely how many days, and how high the temperatures must rise [1]. Once the human body’s physiological capacity to cope with increased heat stress is exceeded, the risks of functional failure, disease exacerbation and death rises rapidly. If the body temperature rises above 38°C, physical and cognitive functions are impaired; above 40.6°C, risks of organ damage, loss of consciousness, and death increase sharply. At high temperatures, displacement of blood to the surface of the body may lead to circulatory collapse [1,2]. Heat waves can cause mortality and hospitalizations due to hyperthermia and similar acute illness, and also by exacerbating pre-existing conditions such as cardiovascular and pulmonary illnesses [3]. Heat waves are exacerbated in urban environments by the urban heat island efect, caused by the concentration of concrete and asphalt surfaces, reduction of vegetation, and anthropogenic heat sources. Urban temperatures can be as much as 8°C higher than the surrounding countryside, though typically the increase is more in the order of 3°C to 4°C [3]. Increasing heat also contributes to smog formation and worsening air quality, both of which are evident problems in urban than rural environments. In urban environments, the efects of heat on air pollution may have a much larger efect on mortality and morbidity than the direct efects of heat stress [4]. Akanni [5] examined the upward trend in temperature in the United State of America (USA) and argued that the number of cases of squamous cell carcinoma was 5.5% higher for every 1°C increment in average temperatures, and basal cell carcinoma was 2.9 % more common with every 1°C increase. Tese values correspond to an increase in the efective UV dose of 2% for each 1°C despite the benefcial efects of solar radiation on synthesis of vitamin D important for health 7 and 12 examined in retrospect the incidences of deaths from heat waves in Europe and observed that the severity of the 2003 event was so peculiar such that short-term mortality displacement contributed very little to the total heat wave mortality. Tese mortalities were at variance across Europe as France recorded more than 14,800 deaths, Belgium, Czech Republic, Germany, Italy, Portugal, Spain, Switzerland, the Netherlands and the UK all reported mortality within the range of 35,000 deaths [6] compared the impact of heat wave on mortality in France between 2003 and 2008 using the Poisson regression model relating the daily fuctuations in summer temperature and mortality in France from 1975 to 2003. Tey discovered a reduction in the incidence of heat wave afer the 2003 incidence due to increase awareness measures embarked upon by the government. What is shocking is the fact that heat waves could also exacerbate mental illness as Dholakia and Amit [7] investigated whether hospital admissions for mental disorders may be exacerbated by heat exposure and heat waves, in Hanoi, Vietnam and found a nexus between heat exposure and hospitalizations for mental illness in Northern Vietnam with relative risks increasing with the length of the heat waves. Te groups of organic mental illness as well as those with mental retardation had the highest increase during these events. Te study demonstrated relationships between admissions for mental disorders and heat waves, especially at a threshold temperature beyond 35°C as there were large diferences between gender, urban, rural residents, and age groups. Men residents in rural regions and aged populations (over 60 years) appeared to face the largest relative risks of being admitted for mental disorders in periods of heat waves. Similarly, Umoh et al. [8] investigated the impacts of both extreme heat and cold waves on human health in retrospect in fve urban cities in India, namely: Ahmedabad, Bangalore, Hyderabad, Mumbai and Shimla spanning between 2005 – 2012. Teir fndings revealed a largely heterogeneous mortality risks across the urban areas as risks increase with intensity of heat (cold) waves. In China, Mitchell et al. [9] reviewed studies on the variation in extreme heat events and their meteorological conditions, focusing on high temperatures during the summer season. Te reviews indicated an upward trend in temperature over most parts of China even when Heat Waves Research and Impacts on Human Health: The Need for Studies in Nigeria: A Review Peter Nkashi Agan* Department of Geography, University of Ibadan, Ibadan, Oyo State, Nigeria Abstract Heat waves comprise of hot and cold waves and hot waves are the number of days when normal daily temperature exceeds its normal limits for consecutive periods. This phenomenon is experiences globally and as such the temperate regions especially countries in Europe and Asia notably France, Germany China, India etc. have and still doing extensive scholarly works on heat waves research while Nigeria is lagging behind on this vital research. The replacements of natural water channels and path for concrete surfaces have led to urban heat island effects raving the entire country. Heat waves are linked a number of issues that directly affect health. There is a need for more studies on the nexus between heat waves and health as it affects the generality of ambient population. This review has enunciated gaps especially in Nigeria for scholars and research students to take advantage of to broaden the frontiers of knowledge. This paper is guided by the introduction, tools and techniques, methodology, gaps and conclusion.