New Nigerian Journal of Clinical Research

: 2021  |  Volume : 10  |  Issue : 17  |  Page : 7--13

A synopsis of human pandemics

Esther L Ismaila1, Bashiru Omeiza Ismaila2, Simeon Omale3, David M Umar4, David Danjuma Shwe5, Nathan Yakubu Shehu6,  
1 Department of Community Medicine, Jos University Teaching Hospital, Jos Plateau State, Nigeria
2 Department of Surgery, Jos University Teaching Hospital, Jos Plateau State, Nigeria
3 Department of Pharmacology Drosophila Laboratory Unit, Africa Center of Phytomedicine Research and Development, and Toxicology, University of Jos, Jos, Plateau State, Nigeria
4 Discipline of Pharmaceutical Sciences, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
5 Department of Paediatrics, Jos University Teaching Hospital, Jos Plateau State, Nigeria
6 Department of Medicine, Jos University Teaching Hospital, Jos Plateau State, Nigeria

Correspondence Address:
Dr. Nathan Yakubu Shehu
Department of Medicine, Jos University Teaching Hospital, P.M.B 2076 Jos, Plateau State


Pandemics have been an important part of human history and have caused widespread morbidity and mortality as well as economic devastation in their wake. As the world struggles to contain its latest pandemic coronavirus disease 2019, it is important to look at all the human pandemics that have been recorded. The PubMed and Google Scholar databases were searched for, all in English language literature, using the search words “pandemics” and “history of pandemics.” Further references were obtained through cross-referencing the bibliography cited in each work. Available literature showed pandemics are a recurrent feature in human existence globally. Detailed description of effects of pandemics in Africa were few. The pandemics were classified according to the periods they occurred. From 430BC to 2020AD, different epidemics largely caused by bacteria and viruses have affected the human. With the recurrent patterns of earlier pandemics and advances in international travel, it is obvious that for the foreseeable future, pandemics will remain a global health challenge.

How to cite this article:
Ismaila EL, Ismaila BO, Omale S, Umar DM, Shwe DD, Shehu NY. A synopsis of human pandemics.N Niger J Clin Res 2021;10:7-13

How to cite this URL:
Ismaila EL, Ismaila BO, Omale S, Umar DM, Shwe DD, Shehu NY. A synopsis of human pandemics. N Niger J Clin Res [serial online] 2021 [cited 2024 Feb 27 ];10:7-13
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Full Text

A pandemic is an infectious disease that has spread spatially through human populations across a large region, across two continents or more, then worldwide.[1] There is a rich history of pandemics involving the human population. These have involved different infectious agents, most notably viruses and bacteria. The farther back in history the pandemic occurred, the more uncertainty about its origin and cause, due to limitations of retrospective scientific inquiry. A summary of all pandemics that have affected humans is presented in [Table 1]. Pandemics have affected humans and to a large extent determined the outcome of events like wars and government. They have been associated with increased superstition but, have also been the stimulus for rapid growth of scientific knowledge and human development. There is little information about most of these human pandemics in Africa.{Table 1}

Earliest records of what may be considered as pandemics are described in biblical texts as plagues. In the old testament of the Bible in the book of Exodus, ten plagues were described. Although these plagues 4included changes in the weather and elements, some of the plagues described that afflicted the Egyptians in the struggle for freedom by the Israelites could be construed as infectious in origin for example that of boils and death of livestock.[2],[3]

One of the earliest pandemics recorded in history was the Athenian plague of 430–26 BC which was characterized by fever, headaches, conjunctivitis, rashes, and vomiting. It was thought to have originated in Ethiopia before spreading to Egypt, Greece, and the rest of the Mediterranean. The cause of the pandemic is disputed, but has been attributed to typhoid fever, typhus, plague, small pox, and Ebola hemorrhagic fever.[2],[4],[5]

The Antonine plague also known as the Plague of Galen (documented by William Galen), was another pandemic that occurred in 165–180 AD. It affected the whole of the Roman empire. It occupied large swathes of territory extended from Iraq to Germany.[2],[6] It was responsible for the death of a third of the population in some parts of the Roman empire including the emperor Marcus Aurelius Antoninus. Smallpox or anthrax is thought to have been responsible for this pandemic.[6]

In the 6th and 8th centuries AD another pandemic, likely bubonic plague, caused by Yersinia pestis occurred in the Eastern Roman empire and is referred to as the Plague of Justinian.[7],[8] Those who had the disease had fever, fatigue, developed buboes mainly in the groin and armpit and became delirious.[2] It was responsible for the death of large numbers of the population. The emperor contracted it but did not die from the disease. The plague of Justinian is considered as the 1st pandemic caused by Y. pestis. It most likely originated in central Asia.[9]

The global outbreak of bubonic plague known as the Black Death was a major pandemic in history due to Y. pestis. It is considered the second major wave or pandemic caused by this organism.[7],[10] Y. pestis, a Gram-negative bacterium, is transmitted mainly by bites from infected rodent fleas. It originated in China in 1334 and spread to Europe along the trade routes in 1347.[2] It had several waves within the 50 years or so that it lasted before its end in 1400. It had a devastating effect on the world at that time and was responsible for the death of 30%–50% of the population of Europe between 1347 and 1353.[7],[10]

A pandemic described as typhus fever was described from the 15th to 17th centuries in association with various wars that were fought in Europe during this period.[11],[12] These wars created unhygienic conditions that encouraged the transmission of body and head lice, Pediculosis humanus and Pediculosis humanus capitis, respectively. These lice are the vectors for the pathogen Rickettsia prowazekii. With improvements in personal hygiene the outbreaks reduced significantly.

An influenza pandemic which although was highly contagious but not very lethal probably affected 75% of the population of Europe in 1781–1782. At this time, the contagious nature of influenza had not yet been established.[13] It was said to have originated from central Asia.[13]

In 1817, what is now considered to be the first cholera pandemic occurred and it lasted until 1823. It was propagated by soldiers involved in two wars within this period who had acquired the disease and spread it on returning home.[14] The second cholera pandemic, 1829–1851, is believed to have started in Russia with a reemergence of the organisms from the first pandemic. This was more severe than the first pandemic and involved every continent except Antarctica. Mecca was pivotal in the spread of this cholera outbreak through pilgrims. John Snow made his famous observation about the transmission of cholera during the second pandemic. It was also during the second pandemic that intravenous fluids were used for the treatment of cholera.[14]

The third cholera pandemic occurred soon after from 1852 to 1859. It achieved its peak between 1853 and 1854 and at this time involved parts of Europe and the Middle East before spreading to involve most of the world.[14] The fourth pandemic of cholera which was from 1863 to 1879 also had Mecca playing a major role in the spread of the disease by pilgrims, similar to what happened earlier in the second pandemic.[14] In this outbreak 30,000 of the 90,000 pilgrims that visited Mecca died of cholera. Wars in Europe involving Austria, Italy, and Germany helped to spread the disease. West Africa was not involved in this outbreak.[14]

The fifth pandemic of cholera (1881–1896) started as an epidemic in Mecca in 1881, then spread to Egypt. It was in Egypt that Koch conclusively proved the organism that caused cholera. The 50% case fatality rate in Europe from the fifth cholera pandemic enabled countries like Great Britain to entrench public health measures that helped to curb the disease subsequently.[14] The disease was severe in Europe and South America. West Africa was again not involved in this outbreak with the postulation that the environment might be protective.[14]

There was an outbreak of influenza in 1889 which emerged from Russia, that was reported to have infected up to 40% of the world's population.[15] It had higher morbidity than mortality and was responsible for 250,000 deaths in Europe.[16] It was at this time that Haemophilus influenza, called Pfeiffer's bacillus by the discoverer, was erroneously thought to be the causative agent for influenza after it was identified in the sputum of sick patients.[15] This influenza pandemic ended in 1892.[16],[17]

A modern outbreak of plague caused by Y. pestis is considered to have originated from Hong Kong in 1894 and was spread worldwide through shipping.[9] However, it may have started earlier in 1855 in Yunan province in China.[10] Steamships from Hong Kong spread the infection to different continents. These included Africa, Europe, Middle East, other parts of Asia and North and South America.[18] The mortality rates were initially high as the disease was estimated to have killed 12.5 million Indians between 1898 and 1918.[10] The mortality decreased with the introduction and adoption of public health measures and later the use of antibiotics. Alexandre Yersin identified the causative pathogen now called Y. pestis in 1894 while Manasori Ogata and Paul-Louis Simond independently discovered the role of the flea in transmission of the disease.[10],[19] There has been a decline in the outbreaks but the disease has established foci of endemicity in every inhabited continent except Australia.[10],[19]

Mecca was again the epicenter of the sixth cholera pandemic in 1899–1923. The city was responsible for initiating and maintaining the pandemic through traveling pilgrims who contracted the disease and spread it to countries like Egypt from where it spread to Europe in 1902. Another outbreak occurred in Mecca in 1907 which spread to other Arab countries. The First World War ensured that the pandemic persisted in Europe. In 1910, cholera spread to South America via ships from Russia. Malaysia had cholera throughout the period of this pandemic.[14] The last local case of cholera in the United States was during the sixth pandemic in 1911.[14]

In 1918 a deadly influenza pandemic named the Spanish flu swept through the globe. It was one of the deadliest events in history and has been described as the mother of all pandemics.[20],[21] Although the exact figure is unknown, it is estimated that this H1N1 virus of obscure origin was responsible for the death of 50–100 million people and infected about a third of the world's population (500 million people).[13],[15],[16],[21],[22],[23] Rapid troop movements during the World War I may have contributed to its rapid spread.[13] The pandemic may have also resulted in the premature end of the First World War.[15] This 1918 influenza pandemic was unusual in several ways. Apart from the almost simultaneous outbreak in different parts of the world, it swept through the world in three rapid waves and the mortality was higher than previous influenza pandemics. It also atypically caused three times higher mortality than expected among the age group 20–40 years with those aged 29 years recording the highest deaths among this age group.[21],[22] In Nigeria the disease was introduced via the ports and spread inland through the railways. It was estimated that 500,000 people died of this disease out of a population of 18 million.[24] The pandemic ended in 1919.[21],[22]

Forty years after the Spanish flu, in 1957, another influenza pandemic nicknamed the Asian flu, thought to have emerged from China rapidly spread to affect the whole of Asia in 3 months. Within 9 months the whole world was affected.[15],[16] The pathogen was an influenza H2N2 virus and accounted for 1–2 million deaths before it ended in 1958.[16],[25] It was a plague that occurred in the modern virology era where vaccines were developed. Most of the vaccines got to the population after the peak of the disease, but may still have reduced the severity of the pandemic.[13],[15]

The latest pandemic of cholera described as the 7th pandemic commenced in 1961 and displayed three distinct phases in relation to its spread. The first phase was from 1961 to 1966, the second from 1970 to 1971, and the third from 1991 to date.[14] It was caused by a different biotype of Vibrio cholerae known as El Tor that had been endemic in Indonesia from where this pandemic emerged. In the first phase the disease spread centrifugally from Indonesia to the rest of Asia as far as USSR and Iraq in 1966.[14] In the second phase the disease spread to involve Africa and the southern coast of Europe. It was severe in West Africa which had not been involved in earlier pandemics and Nigeria was one of the countries affected.[14] The availability of oral rehydration salts at this time was an important development in the treatment of the disease. The third phase commenced in Peru, South America which had not had cholera since 1895 from where it spread to other countries in South America.[14] There was an outbreak in 1992 of cholera by the O139 strain of V. cholerae in India that spread to Bangladesh and Thailand triggering concerns that this might be the onset of an eighth pandemic.[14]

The Hong Kong flu was another influenza pandemic which started in 1968 and ended in 1970. The causative influenza virus was named A H2N3. It was spread by flights to different parts of the world.[15] It was estimated to have infected 1–3 million people and caused the death of an estimated 0.8 million.[13],[15],[16],[25] It was not as deadly as its predecessor probably due to the presence of the neuraminidase antigen (N2) which was identical to that in the influenza virus that preceded it.[25]

The reports of opportunistic infections in homosexual men in the US in 1981 heralded the discovery of one of the most devastating infections to affect humans caused by retroviruses.[26],[27],[28] Acquired immunodeficiency syndrome (AIDS) is caused by the human immunodeficiency virus (HIV). The disease is a zoonotic transmission from nonhuman primates with simian immunodeficiency virus to humans.[26],[29],[30],[31] The pandemic which has spread to affect more than 80 million people worldwide has caused the death of more than 40 million.[29] It is spread mainly by sexual contact, needle sharing by intravenous drug users and unsafe blood transfusions. Sub-Saharan Africa has been particularly vulnerable accounting for nearly 70% of the global HIV case-load.[29],[32] Recently there has been some reduction in new infections and deaths from AIDS-related causes which has been attributed to both treatment and preventive measures which need to be sustained.[32],[33],[34]

In 2003 a then novel coronavirus (CoV) which was later given the name severe acute respiratory syndrome (SARS) CoV emerged from Guangdong province, China, and rapidly spread to 31 countries in 5 continents infecting 8422 people and resulting in 916 deaths.[35],[36],[37],[38] The major symptoms were fever, dyspnea, chills, muscle aches, weakness and nonproductive cough. Nasal discharge and sore throat were less common.[35],[38] The disease was the first known pandemic caused by a CoV. The virus was believed to have jumped to humans from exotic wild animals from the overcrowded conditions created in a wet market. The infection then continued spreading via human to human transmission, creating fears that it could happen again.[38] This fear proved to be well founded.

Another influenza pandemic by a new strain of H1N1 virus was detected in 2009 almost simultaneously in Mexico and US, referred to as the swine flu pandemic.[25],[39],[40],[41] It quickly spread to other countries and within 3 months had spread to 122 countries with 134,000 laboratory confirmed infections and 800 deaths.[25] Fever and cough were the most common symptoms and it disproportionately affected younger members of the population.[42] By the time WHO declared the pandemic over in August 2010, there were 18,500 laboratory confirmed deaths though, mathematical estimates place the number of deaths between 151,700 and 575,400.[25],[43],[44]

The middle east respiratory syndrome corona virus (MERS-CoV) or MERS is a corona virus which was first identified in Saudi Arabi in 2012. As at September, 2012 there were 2,494 laboratory confirmed cases, 858 related deaths and it had been reported in 27 countries.[45] Twenty six other countries have reported cases of MERS including Algeria, Austria, Bahrain, China, Egypt, France, Germany, Greece, Islamic Republic of Iran, Italy, Jordan, Kuwait, Lebanon, Malaysia, the Netherlands, Oman, Philippines, Qatar, Republic of Korea, Thailand, Tunisia, Turkey, United Arab Emirates, United Kingdom, United States, and Yemen. The symptoms include fever, cough, and shortness of breath which is noted in most corona virus diseases. Gastrointestinal symptoms have also been reported. A number of cases have been attributed to human-to-human transmission but current scientific evidence has suggested that dromedary camels are a reservoir for MERS-CoV. Other outbreaks have occurred in other countries such as United Arab Emirates, and the Republic of Korea.[46],[47]

Although Ebola viral disease had been infecting humans in the Central African Region it was not considered a major epidemic threat.[1],[48] this perception continued until there was a severe outbreak that reported 1779 cases with 961 deaths involving four West African countries, Guinea, Liberia, Sierra Leone, and Nigeria. There were also two infected US aid workers that were evacuated to the US after they had been administered an experimental serum treatment.[49] The disease is caused by Ebola virus which has bat and other “bushmeat” as possible hosts. The disease is characterized by fever, vomiting, diarrhea, and generalized bleeding.[49] The pandemic started in 2013 and ended in 2016.

Another viral disease caused by Zika virus came a global attention shortly before WHO declared it a public health emergency of international concern in February 1, 2016.[50] Before now, it had been an obscure disease described since 1947 after isolation from a febrile Rhesus monkey in Zika forest, Uganda.[50],[51] Zika virus was first reported to infect humans in 1953 in Nigeria.[52],[53] The vector for Zika virus is the Aedes mosquito.[50],[51],[53],[54] It emerged from obscurity in late 2014 when there was a rapid rise in cases in Brazil and then to the Americas.[54] There were epidemics previously in some pacific islands.[50],[51],[54] It was presented with pruritic rashes, low-grade fever, and joint and muscle pains. Its association with neurological defects, materno-fetal transmission, and microcephaly were major concerns.[55],[56] The incidence has been on the decline since 2017.[56]

In 2019, another novel CoV emerged from wet animal markets in Wuhan, Hubei province in China and very rapidly spread to cause a worldwide pandemic. The virus is called SARS-CoV-2 and the disease it causes is known as COVID-19.[18] Although public health measures like quarantine, shelter-in-place and closure of borders were instituted, the disease was not contained.[18] To date (April 17, 2020) there are 2,241,359 cases with 152,551 deaths spanning across 211 countries.[57] The symptoms consist mainly of fever, fatigue, dry cough, and shortness of breath.[58] As at September 26, 2020, there were 32,613,844 cases globally and out of this number there were 989,728 deaths. America has had the highest number of cases accounting for 16,285,399 confirmed cases and 547,872 deaths giving a case fatality rate of 3.4%, while Oceania has had the lowest number of cases with a total of 32, 753 confirmed cases and 952 deaths giving a case fatality rate of 2.9%. Africa has had 1,446,132 cases with 34, 855 deaths. This showed a 2.4% case fatality rate.[59] Globally Africa has been the least affected, but there are concerns as to whether these are the real numbers or due to inadequate testing. The disease is still evolving and a number of public health measures have been carried out in different countries to reduce the spread of the infection. These include use of face masks, frequent hand hygiene with soap and water or with alcohol-based hand sanitizers containing about 60% alcohol, avoiding touching eyes, nose, and mouth with unwashed hands, prevention of spread by oronasal secretion, physical distancing of not < 6 m, crowd prevention and self-reporting of symptoms to ease disease detection and confirmation.[60]

Nigeria has recorded 58,198 confirmed cases and 49,722 have been discharged and 1,106 deaths have been recorded, with a case fatality rate of 1.9%.[61] Ongoing research will provide even more information as we witness our latest pandemic.

In conclusion, pandemics are part of human existence. They appear to be increasing in frequency, in the past 20 years we have had 5 pandemics [Table 1]. This is not surprising considering technologically advanced global high-speed travel, incursions of humans into natural habitats of animals and current animal husbandry practices. These singly and in combinations increase the likelihood of zoonotic transmission between animals and humans. Improvements in science and technology also means that we may be able to detect the pandemic agents faster and more accurately. However, time will tell whether these will translate to reductions in the pandemics or the devastations caused by them.


We are grateful to all members of the COVID 19 research consortium: John Aguiyi, Pam D. Luka, Christopher Yilgwan, Emmanuel N. Nnadi, Filibus D. Dami, Dr. Dung D. Pam, John Bimba, Nantawe Gurundima, Esala Abene, Joyce Bartekwa, Uzal Umar, Victor B. Ojeh, Francis Agwom, Nantok Dami.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.


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