Most of these parasites are usually located and distributed in the tropical regions of the world because of some peculiar features of these areas. Typically examples include the Plasmodium parasites which are inherently found in tropical regions of the world especially in the African continent (Nigeria for example). Plasmodium which causes malaria in man has over the years even now impacted negatively on the wellbeing and socioeconomic welfare of human beings, and this scenario has resulted to the high morbidity and mortality rates recorded in malaria disease cases across Africa. Most parasitic diseases (malaria) are major diseases of the tropical and subtropical regions; and these diseases which are often known as tropical infections are serious public health problems in these parts of the world where the diseases are endemic. Aside the climatic conditions of the tropical and subtropical regions which make them more prone to most parasitic infections than the temperate world; poor health policies, poor environmental sanitation and poverty among other factors are among the key reasons why some of these diseases are still widespread in these regions, and the situation is pathetic in most developing parts of Africa. Parasitic diseases are usually common in rainforest parts of the world (the tropical and subtropical regions) because such environment favour the existence of the causative agents of such infections. For example, malaria caused by Plasmodium species is more prevalent in tropical and subtropical regions than in temperate regions where the environmental condition is cold and cannot favour the development of the parasite. Below are some of the reasons for the disparity in parasitic diseases that occur in tropical and temperate regions of the globe.
- The tropical (hot) regions are usually ecologically relatively less stable than the temperate (cold) regions. This imbalance gives parasites the occasion to disturb and disrupt the ecological imbalance between man and host environment.
- Most parasitic diseases (malaria and guinea worm infection) have either been totally eradicated or contained in temperate regions.
- Due to the usually high rainfall experienced in the tropics than in most temperate regions, there is low level of public health improvements in most tropical areas especially in countries that have not yet put in place a sustainable environmental and pollution control measures.
- Most parasites complete their life cycles in arthropods which find the tropics (that are usually warm and humid) to be most suitable and favourable for their fast breeding and development.
- The poor state of hygiene and lack of access to potable water as well as poor health facilities in the developing countries could also contribute to the chronic and endemic nature of some parasitic diseases in the tropics.
Chiodini P.L., Moody A.H., Manser D.W (2001). Atlas of medical helminthology and protozoology. 4th ed. Edinburgh: Churchill Livingstone.
Ghosh S (2013). Paniker’s Textbook of Medical Parasitology. Seventh edition. Jaypee Brothers Medical Publishers,
Gillespie S.H and Pearson R.D (2001). Principles and Practice of Clinical Parasitology. John Wiley and Sons Ltd. West Sussex, England.
Gutierrez Y (2000). Diagnostic pathology of parasitic infections with clinical correlations. 2nd ed. New York: Oxford University Press.
John D and Petri W.A Jr (2013). Markell and Voge’s Medical Parasitology. Ninth edition.
Mandell G.L., Bennett J.E and Dolin R (2000). Principles and practice of infectious diseases, 5th edition. New York: Churchill Livingstone.
Roberts L, Janovy J (Jr) and Nadler S (2012). Foundations of Parasitology. Ninth edition. McGraw-Hill Publishers, USA.
Schneider M.J (2011). Introduction to Public Health. Third edition. Jones and Bartlett Publishers, Sudbury, Massachusetts, USA.