Variations in Global Life Expectancy with a Focus on African Countries

Life expectancy at birth which often tends to be abbreviated as LEB, is a terminology that has been coined for a statistical measure of the average time an organism or in the case of human beings, an individual, is expected to live, based upon the year of its or his or her birth, it’s or his / her current age as well as other demographic factors including gender [1]. It has been iterated that life expectancy at birth (LEB) most often have been defined in two ways that include cohort life expectancy at birth (Cohort LEB) and Period life expectancy at birth (Period LEB) [1].

Cohort life expectancy at birth (Cohort LEB) has been defined as the mean time period of an actual birth cohort that relates to all individuals who have been born within a given one year and this can be calculated for cohorts of individuals who had been born many decades earlier, such that all the members within their cohort have died. Period life expectancy at birth (Period LEB) is a terminology that has been coined for a hypothetical cohort of individuals or organisms that have been assumed to be exposed, from birth to death, to the mortality rates that had been observed over a given year [2].

National life expectancy at birth (National LEB) figures that are reported by statistical national agencies as well as international organizations are said to indeed represent estimates of period life expectancy at birth (Period LEB). Some of the documented historical summations related to life expectancy at birth include [1].

Within the bronze age and the iron age, life expectancy at birth was documented to be 26 years.

The 2010, world life expectancy at birth (World LEB) was documented as 67.2 years.

With regard to life expectancy at birth in Swaziland (Eswatini) is approximately 49 years whilst the life expectancy at birth in Japan is approximately 83 years.

The combination of high infant mortality and deaths among young adulthood related to accidents that emanate from accidents, epidemics, plagues, wars, especially preceding the practice of modern medicine which was widely prevalent, did significantly lower the rates of life expectancy at birth (LEB). For instance, with regard to a society that has a life expectancy at birth of 40 years, that society would have few who die at the age of 40 years precisely and majority of individuals belonging to that society would prior to the age of 30 years or after 55 years.

With regard to populations that are associated with high infant mortality rates, life expectancy tends to be very sensitive to the death rates within the first few years of life. It has been iterated that in view of the sensitivity to infant mortality, life expectancy at birth (LEB), could be subject to gross interpretation which does to lead an individual or a group of people to have the opinion that a population that has a low life expectancy at birth (low LEB) would automatically have a small proportion of older people [3].

An alternative measure such as life expectancy at 5 years of age (e5) could be utilized to exclude the effect of infant mortality in order to provide a simple measure of overall mortality rates other than within early childhood and with regard to the aforementioned postulated hypothetical population, life expectancy at 5 would another 65.

Aggregate population measures, for example, the proportion of the population within varying age groups, should also be utilized together with individual-based measures including formal life expectancy when undertaking the analysis of the population structure and dynamics. Nevertheless, pre-modern societies had universally higher mortality rates and universally lower life expectancies at each age both males and females and this example is extremely rare.

With regard to societies that have life expectancies of 30 years, for example, a 40-year remaining time span at the age of 5 years could not be un-common, but a 60-year-old one was.

It has been stated that with regard to mathematical computation, life expectancy refers to the mean number of years that remain at a given age taking into assumption the age-specific mortality rates do remain at their most recently measured levels. [4] It tends to be denoted by ex which does refer to the mean number of subsequent years of life an individual who is now aged x, according to a particular mortality experience. It has also been documented that longevity, maximum life span, and life expectancy are not synonymous with regard to meaning. It has additionally been stipulated that life expectancy has been defined with regard to statistical means as the mean number of years that remain for an individual or a group of individuals at a given age. With regard to definition, longevity, does refer to the characteristics of the relatively long- life span of some members of a population group. Maximum life span does refer to the age at death of the longest-lived individual among the population or species. Furthermore, in view of the fact that life expectancy is an average figure, a particular individual could die many years preceding or many years pursuant to the expected survival. The terminology maximum life span does have a different meaning and tends to be more related to longevity.

It has been stated that globally, the average life expectancy at birth was 71 years which was 70 years for males and 72 years for females over the period of time between 2010 and 2015 based upon the United Nations World Population Prospects Revision [5], or 69 years that represented 67 years for males and 71.1 years for females for 2016 according to The World Factbook [6,7]. Based upon the 2015 the World Health Organization (WHO) data, on average women tend to live longer in comparison with men in all major regions as well as in all individual countries with the exception of Mali and Swaziland (Eswatini) [5].

It has been documented that the countries that have the lowest overall life expectancies per World Health Organization (WHO) are Sierra Leone, the Central African Republic, the Democratic Republic of the Congo, Guinea-Bissau, Lesotho, Somalia, Swaziland (Eswatini), Angola, Chad, Mali, Burundi, Cameroon, and Mozambique. It has additionally been documented that out of these countries with the lowest overall life expectancies, only Lesotho, Swaziland (Eswatini), and Mozambique in 2011 had been suffering from an HIV prevalence rate that was higher than 12% within the 15 years to 47 years age group [8].

It has been iterated that it can be problematic to compare life expectancies from birth across various countries and that different definitions do exist for live birth and still birth even among more developed countries and less developed countries quite often tend to have poor reporting [9].

Variations in global life expectancy does depend upon many factors including the Gross Domestic Product of the individual countries, the percentage of the Gross Domestic Product that is allocated by the countries to Health care delivery and prevention of diseases, the life style of the individual countries and efforts made at preventing disease as well as managing disease, the quality of good roads to avoid accidents, the transportation system of the countries, the availability of effective ambulance and resuscitative services, the level of education, the availability of effective community development, the realisation of individuals to make concerted efforts to prevent disease, the ability of each district, region, nation, sub-continent and continent to establish their own community diagnosis, identify priority areas to help improve quality of life and prolong life, the ability to treat disease by providing general management, specific management, symptomatic management, management of complications, convalescent management and prevention of recurrence of disease. Generally, more developed countries tend to have better and improved quality of life and higher life expectancies in comparison with developing countries for various reasons. Nevertheless, it is known that if the developing countries that have low life expectancy rates can focus on improving quality of life and taking more effective steps to prevent unnecessary preventable deaths through concerted efforts and education activities the quality of life and life expectancies of those countries would improve gradually.

Majority of countries in Africa have continued to have lower life expectancy rates in comparison with the developed countries. A good way for African countries to help improve their national life expectancy rates would require studying of the top 20 most common causes of death in their countries and taking steps to prevent those deaths. A study of the commonest 20 causes of death in majority of African countries does illustrate that majority of the causes of death are preventable and unnecessary deaths and the conditions are usually treatable. It is therefore necessary to provide data that provides information on the commonest preventable deaths in African countries to inhabitants of Africa to enable each African country take steps to remedy the situation. The World Health Organization has continually made efforts to provide data on global life expectancy and data on various diseases globally but it would appear as if perhaps more effective steps would be required to help Africans to help themselves by establishing national and international efforts in collaboration with the World Health Organization to improve quality of life as well as raise life expectancy of life in Africa as a whole.

Life expectancies of countries vary from time to time and the World Health Organization, The World Bank, The CIA, Wikipedia, the free encyclopedia, The United Nations, The Global Burden Disease 2010 study, OECD 2016, and the UN World Population prospects 2015 have tabulated various aspects related to the global life expectancy table to enable citizens of all countries in the world to be familiar with the life expectancies of their countries in relation to all other countries in the world to enable them make efforts to improve upon the life expectancies in their countries in collaboration with their neighbouring countries and the rest of the world and Tables 1 to 6 with their corresponding reference sources illustrate these tables based upon data obtained from different time periods (see references 10 to 23 for the sources of the tables and other references to learn from).

The ensuing book contains various documentations related to life expectancy of African countries with a highlight of steps that need to be taken to improve upon the life expectancy rates of African countries.