In the second millennium BCE,
a series of catastrophes struck
the Egyptian civilization during
the period known as the New
Kingdom. Talmudic and Biblical
accounts of these catastrophes
refer to them as the ten plagues
of Egypt, which were visited upon
the Pharaoh and his Egyptian
subjects for enslaving the Israelites,
led by Moses. The ten plagues of
Egypt described in the Book of Exodus
are the first example in an historical,
written record of what today
might be described as
"emerging infections."
Causes and interpretations of the ten
plagues of Egypt have fascinated
theologians, historians,
Egyptologists, musical composers,
scientists, and physicians for
centuries. More recently, modern
scientific disciplines—epidemiology
(the study of the occurrence of disease
in human populations), epizootiology
(the study of epidemic disease in
animals), entomology (the study of
insects), microbiology (the study of
microbes) and toxicology (the study of
the effects of poisons)—have
attempted to explain exact causes for
one or more of these plagues. In
recent years, re-interpretations of
ancient texts as well as new
information about environmental
factors and disease causation, have
allowed unique interpretations of this
series of early public health
catastrophes.
Yet, despite centuries of
speculation and study,
fundamental questions remain.
What were the actual causes of the plagues of Egypt? Can events that occurred so long ago and are known only through religious story and myth be interpreted using modern scientific methods? Previous explanations of the plagues have ranged from the theological, the supernatural, the quasi-scientific, to the scientific. On this site, the new plaguescapes , a resurrection of an award-winning site from the early days of the Internet, you'll find a fascinating new interpretation for each plague based upon modern epidemiological principles. The authors looked closely at previous explanations and, using Occam's razor as needed, reduced discordant explanations to the simplest and most logical. They assimilated these previous analyses and conclusions in developing their own hypothesis that the first nine plagues built upon each preceding plague and precipitated the final, devastating tenth plague.
Did the plagues occur?
There is little, if any, secular information to substantiate the account of the ten plagues of Egypt in the Exodus. Some Egyptologists consider the bible as perhaps only a collection of religious archetypal stories and myths, not as history, noting half a millennium or more passed between the time these events may have occurred and the time of the first known written Hebrew literature. A strictly historical analysis would reveal that if the plagues and the ensuing exodus did occur, they must have transpired before 1200 B.C.E., when the so-called "Israel" stelae of the New Kingdom pharaoh Merneptah describes a people—not a country—called "Israel," which had already reached Canaan. (The Israel or Mernerptah stelae, shown here, is from the fifth year of the reign of pharaoh Merneptah. It is the earliest historical reference to the Israelites. It celebrates victories over Canaanite tribes, including the Israelites: "Israel [a people] is laid waste, his seed is no more." Archaelogist Frank Yurco believes that relief carvings in the temple of Karnak at Luxor also depict the slaying of Israelites during campaigns of Merneptah. Biblical Archaelogy Review, July/August 1997.)
If the plagues did occur, why were there no specific citations in the Egyptological literature? There is some evidence, separate from Talmudic and Biblical accounts, that the plagues occurred. Physician Greta Hort, in one of the first and most complete analysis of possible causes of the plagues (Hort, 1957, 1958), refers to passages from the Admonitions of Ipuwer, a translation by Egyptologist Sir Alan Gardiner of an ancient Egyptian papyrus that suggests that a series of catastrophes occurred at the end of the Middle Kingdom, to support her contention that the plagues occurred. The so-called neo-catastrophrist Immanual Velikovsky, author of Worlds in Collision and Ages of Chaos (Velikovsky, 1950, 1973), also cites passages from this text in his interpretation of the causes of the plagues.
If Egyptological literature can be found suggesting some semblance of their occurrence, who might best "fit" as the candidate for Pharaoh presiding over the plagues' occurrence? If a specific Pharaoh can be identified (and satisfactorily reconciled within the more accepted Talmudic and Biblical chronological time frames), when and where in time and place (theological and Egyptological) would the plagues and the ensuing Exodus have occurred?
Who and when?
Scholars disagree as to who the Pharaoh was who presided over the plagues and the Exodus. The two Pharaohs most often postulated as presiding over the plagues, Ramesses II and Tuthmosis III, span different time periods.
Citing first century A.D. Jewish theologian Josephus as his authority, Cecil B. Demille chose Ramesses II for his interpretation of events in his authentic rendition of the scriptures-the 1956 film,The Ten Commandments. The Biblical scholar Werner Keller (Keller, 1981) also reasoned that Ramesses II was the Pharaoh. Australian parasitologist, H. M. Duncan Hoyte, citing Egyptologist John J. Bimson, concluded that the Pharaoh was Tuthmosis III (Hoyte, 1993). Hoyte suggests the ten plagues took place under Tuthmosis III (1479-1425 B.C.E.) over an eleven month span, beginning in July through August and lasting until April through May of the following year.
Velikovsky's interpretation appears to concur with Hoyte, identifying a "Taui Thom the last king of the Middle Kingdom. He is the Tau Timaeus (Tutimaeus of Manetho)." But Velikovsky tied the plagues and the fiery pillar and parting of the Red Sea to other contemporary Old and New World historical accounts. Velikovsky's overall explanation is a series of major climatological series of disasters precipitated by a comet and coinciding with the Hyksos invasion. Unfortunately, the Hyksos period (2nd Intermediate Period, 15th Dynasty [Hyksos] 1640-1532 B.C.E.) does not coincide with any of the four Tuthmosis's Velikovsky suggested as the putative Pharaoh.
Neither of the two Pharaohs—Tuthmosis III or Ramesses II— suggested by most scholars, nor the duration of ten months within which these plagues may have taken place, are incompatible with the selected notations contained in the Ipuwer papyrus citations.
Where?
Scholars do agree that the ancient city of Memphis, (today, Mit Rahina), located at the mouth of the Nile delta, was the residence of late Middle Kingdom and early New Kingdom Pharaohs (Gilbert, 1976). A consensus supports the notion that the Land of Goshen (where the Israelites dwelt) was somewhere northeast of Memphis, near ancient (now lost) city of Heliopolis, the "city of the sun," a few miles north from present day Cairo.
The First and Second Plagues
Prior to the germ theory, the only explanation for the first plague was non-contagionist—an unknown contamination, which caused an extensive fish kill (Bryant, 1810). Since the advent of the germ theory, various authors have postulated more specific infectious and non-infectious causes. Silt was an early candidate as the cause of a reddish Nile; later, this explanation was refined to a specific silt known as "marl," originating from Ethiopia and carried by a cresting Blue Nile. Velikovsky proposed that cometary red dust caused the Nile to turn color.
Recent explanations of the cause for red colored waters have favored protozoan, zooplankton, both salt and fresh water algal (phytoplankton) blooms, and dinoflagellates. Ehrenkranz and Sampson attributed a dinoflagellate bloom to rising water temperatures along the outflow of the Nile caused by an El NiñoJ Southern Oscillation (ENSO) teleconnection, which would have occurred about the time of the vernal equinox and would have resulted in two to three months of progressive climatic warming. The blooms were blown upriver by prevailing winds to lands occupied by Egyptians, but not to Goshen, which lies to the east (Ehrenkranz and Sampson, 2008).
All of these various blooms—plant, fungal or protozoan—deoxygenate water and produce noxious toxins for both fish and frogs. Without predator fish, frogs could initially breed freely in both ponds and the Nile and overpopulate the river, eventually escaping the anoxic, toxic, and putrefying environment by migrating to land, hence to die on land and to decompose along with the fish. The Nile and adjacent land would thus become fouled, and the waters dangerous to drink or to bathe in.
Scientist Siro Trevisanato and filmmaker Simcha Jacobovici are recent adherents of the idea that the plagues were initiated by the eruption of the ancient volcano Thera (now the Greek island of Santorini) (Trevisanato, 2005; Jacobovici, 2006), which occurred approximately two centuries earlier than the most accepted dates for the plagues. Jacobovici’s claims, in the TV docudrama Exodus Decoded, have been criticized by archeologists and religious scholars for their circular logic and reliance on suppositions. More recently, in a series of articles with declarative titles, Trevisanato cited the existence of an ancient medical papyrus that includes recipes for the treatment of burns without the use of water (the usual treatment for most types of burns) as further proof of the Thera hypothesis. The presumed burns were caused by contact with the water of an acidic Nile (from sulphates in volcanic fallout) and since the river was acidic, there was insufficient water for treating burns in the usual fashion (Trevisanato, 2006).
Citing the Exodus account in the Bible, Patricia A. Tester of the National Marine Fisheries Service, writing in the Annals of the New York Academy of Science, noted that while fewer than 50 out of approximately 5,000 known phytoplankton species are toxic, those which possess toxins can be dangerous to aquatic life. In the same publication, Ewen C. D. Todd of Health Canada, referring to historic and prehistoric data, cited nearly two dozen examples of specific phytoplanktons causing various outbreaks throughout the world. W. W. Carmichael and I. R. Falconer listed diseases associated with fresh water blue green algae. Aquatic ecologist Joann M. Burkholder, of North Carolina State University, described a dinoflagellate, Pfiesteria piscimorte (found in estuary waters) that is capable of, as the species name implies, killing fish.
Why did the waters turn red?
Our conclusion
Neither an unstated contamination, cometary dust nor silt would by themselves explain all of the phenomena described above. In addition, the Nile, its tributary waters, well water, and other bodies of standing water were fresh. Most of the above mentioned aquatic, phytotoxic blooms occur in salt or brackish water, with the exception of the relatively modern discovery of freshwater blooms.
We therefore believe that a freshwater dinoflagellate biomass bloom was responsible for both the change in the color of the Nile, the death of the fish, and subsequent population explosion in the frogs.
The Consequences
The death of fish— "an important source of protein and minerals, which filled an important role in the Ancient Egyptian's diet" (Darby, 1977)—was more than an inconvenience, and was the first of many nutritional compromises caused by ensuing plagues to be inflicted on the Egyptian Empire, culminating in the last plague. The eventual death of frogs would remove an important natural enemy of the insects, which became free to multiply unhindered and cause subsequent plagues.
The Third Plague
Entomologist Dr. Richard L. "Mothman" Brown, Curator of the Mississippi Entomological Museum at Mississippi State University has noted that any mention of an insect in the book of Exodus would predate the first taxonomic attempts by Aristotle to classify insects (or arthropods) by nearly one thousand years. Thus, any arthropod may be considered as a putative vector of the third plague, including the members of the Class Arachnida—soft ticks, hard ticks, scorpions, spiders, and mites. All these arthropods abound in Egypt (Defense Pest Management Information Center, 1988).
The original Hebraic term for "lice" (chinnim) is most often translated as "vermin." This term is commonly construed as an arthropod skin infestation, and not as a flying insect. The term also implies that these multiple offenders could be visibly recognized. Thus, the otherwise ingenious conclusion by Korzets in a letter to the British medical journal The Lancet that the cause of the third plague "itch" was due to the microscopic scabies mite (Sarcoptes scabiei), is probably incorrect, although David J. Sencer, MD, MPH, former director of the Centers for Disease Control and Prevention, noted that the chronic allergic sequela of this infestation, "beggars' itch," is an alternative explanation.
Of the three human body lice known today (Pediculus corporis humanis, P. capitis humanis, Pthirus pubis), none fulfill the description of the macroscopic infestation "on man and beast," since these lousy candidates are species-specific, and do not infest non-human hosts, as the text clearly states.
Alternative explanations?
• Indiscriminate biters such as the soft tick (Orthinodoris moubati) or hard tick (Boophilus annulatus), or a maggot infestation, termed myiasis, (e.g., Dermatobia hominis).
• One of the Simulian species of black flies capable of transmitting onchocerciasis ("river blindness") that occurs in many areas of eastern Africa, including the Sudan. The dermatosis caused by these flies is singularly characterized by intense itching.
• One of over forty species of mosquito capable of transmitting disease that have been catalogued in Egypt. The Australian physician H. M. Duncan Hoyte noted that an alternative to the Hebraic translation of "chinnim" is the Greek "sciniphes," or mosquito/gnat.
• Midges (a.k.a. gnats,"no-see-ums," and "punkies") and sand flies (Phlebotomus species) are bloodsucking flies that fulfill the near-microscopic description of "lice." These are nematocerous flies whose larvae and pupae live in moist soil. They may appear to originate in "dust" where their pupae develop, and after pupation, fly out from what would appear as dirt or dust.
• Paederus or rove beetles (family Staphylinidae), which can form intense swarms under the right conditions, but rove beetles do not bite (Norton and Lyons, 2002; citation for rove beetles).
Phlebotomus papatasi, a vector of the sand fly fever virus.
Our conclusion
Although entomologically correct for Egypt, ticks or maggots are too macroscopic to warrant usage of the term "vermin." And, like lice, ticks and fly larva are incapable of flying, a requirement implied by the biblical passage. Black flies are too large and recognizable to be called vermin, and the pruritis induced by an allergic reaction to the death of O. volvulus microfilaria takes months or years to appear.
Hoyte preferred the mosquito, Culex antennatus, as the most likely explanation for "lice" even though mosquitos are relatively large and easily recognized. In choosing the mosquito as the explanation of the third plague, Hoyte dismissed the midge and sandfly as both the cause of this infestation and as a possible vector for subsequent plagues.
Eight species of midges (Culicoides) and seven species of sand flies (Phlebotomus) have recently been identified in Egypt (Defense Pest Management Information Center, 1988). The latter is a vector of sandfly fever and leishmaniasis (visceral and cutaneous). Neither zoonoses is likely to be confused with subsequent plagues.
Culicoides canithorax (the Biting Midge)
Unlike the sand fly, which uses cracks in walls and stone outcroppings to lay its eggs, midge larvae feed on abundant microorganisms in decomposing detritus, such as the remains of fish and frogs. The eventual explosive emergence of adult flies might be well construed as a plague coming from "all the dust of the land." And, unlike many blood-sucking insects such as lice, these tiny, annoying hematophagous flies are not species-specific—that is, they bite both humans and animals with a vengeance, as suggested by one species name, C. vexans. Bites of these minute flies cause severe local reactions, intense itching, and wheal formation (James and Harwood, 1969).
Until recently, midges were considered "nuisance" arthropods, incapable of transmitting infectious agents. However, these flies have increasingly been recognized as biological vectors of a number of human and animal viral diseases. Thus, we conclude that the midge or gnat (Culicoides species) was the cause of the third plague and the biological vector for the fifth plague.
The Fourth Plague
The "swarm of flies" has been given numerous interpretations, but should be distinguished from the third plague of lice. Some renditions attribute a common cause or causes. Hoyte noted that the life cycle and bionomics of the stable fly (Stomoxys calcitrans) coincides with the ebbing of the Nile in September, when abundant rotting vegetation fosters ideal harborage for its emerging larvae. Entomologist Charles Brues listed 31 species of Stomoxydinae, including S. sexvittata Roubaud (now S. bilneata Gruenberg). In addition, according to Dr. Brown, Stomoxys nigra Macquart occurs throughout Africa and attacks cattle, horses, and people. Competing, alternative explanations of the "swarm" are the house fly (Musca), the tsetse fly (Glossina), horse flies (Tabanus), and black flies (Simulium).
The attitude of a Simulium reptans
The house fly does not bite. The other three are biters, blood suckers, and capable of causing severe pain, local irritation, inflammation, swelling and itching.
Glossina and Stomoxys species, however, are the only two of these fly genera where both the male and female take blood meals. Bites of both flies necessitate ripping of flesh, often leaving open puncture wounds, leading to secondary infections. Unlike the annoying sand fly, the intensity and severity of swarms of both tsetse and stable flies have induced stampedes in wild animals and anemia in penned cattle. All of the aforementioned flies are also capable of transmitting infectious agents, but only Glossina and Stomoxys appear to be appropriate insect vectors for either one or both of the subsequent two plagues. However, as discussed later, we believe that the stable fly (Stomoxys) better fulfills the role as the cause of the fourth plague.
Author's (JSM) swollen left hand following single bite on the top of the hand from a stable fly, Stomoxys calcitrans, on Cape Cod, Massachusetts, Summer, 1976.
In summary, the sequelae of plagues one and two appear to have generated opportunity for plagues three and four. Denied potable water or water in which to bathe, the Egyptians and their livestock would be more exposed to infestation, attack, and ensuant, secondary infections. Either mechanically or biologically, at least one kind of fly inoculated pathogenic viral, bacterial or protozoan organisms into animal and humans, causing subsequent disease. Thus, the third and fourth plagues might be logically linked to the fifth and perhaps to the sixth plague.
The Fifth Plague
The fifth plague is probably the first written record of a true epizootic—a disease inflicted upon animals but not humans. A proper proposal should account for this selectivity, as should any hypothesis regarding the subsequent sixth plague, a zoonosis that affected both animals and humans. Specifically, the fifth plague struck many hoofed animals: horses, donkeys, camels, cattle (including oxen) and sheep. Hoyte concluded that the omission of goats and pigs "..is of social, not epidemiologic significance." However, the fact that goats and pigs, which were of common occurrence in Egypt at that time, were not mentioned is relevant, providing negative evidence-clues as to what the plague may have been.
Fifth Plague of Egypt 1800 (The Seventh Plague?) by Charles Turner (1773-1857).
The fifth plague, or "murrain," appears to be specific for certain hoofed mammals, sparing domestic pets and wild carnivores, as well as birds, amphibians and reptiles. In addition to six candidate diseases (1-6) proposed by previous authors, we propose four other lesser known, arthropod-borne African epizootics infecting hoofed mammals (7-10):
1. Anthrax (Blane, 1890; Hort, 1957) is a severe bacterial infection capable of being transmitted by various direct and indirect means, including mechanical transmission by biting flies. Anthrax can infect a wide range of animals, especially goats, and wild animals, including elephants, hippopotami and impala (but not frogs as suggested by Hort). These animals are not included in the biblical account, which is an otherwise complete list of animals affected. Anthrax can also cause human disease; its cutaneous form is associated with a 5 to 20 percent human mortality, an observation that presumably would have been recorded had it occurred.
2. Babesiosis (Ceccarelli, 1994; Gombert et al, 1982; Fitzpatrick et al, 1969), is a hard tick-borne protozoan disease mimicking malaria that is capable of causing disease in all the animals listed in the bible. However, as noted by Hoyte, each equid and ruminant has a different and specific genus of tick vector; moreover, these tick vectors are large, easily recognized during attachment, and therefore likely to have been noted.
3. Surra (common name Debab) (Hoyte, 1993) is a protozoan disease caused by a trypanosome (T. brucei evansi). While causing disease limited to equids (and ruminants), surra is mechanically transmitted by bites of the tse-tse (a fly)—like the related trypanosomiasis, sleeping sickness, that affects man—and the stable fly. However, the tse-tse distribution does not extend into northern Egypt, and while stable flies are cosmopolitan, the disease's present enzootic range in Africa suggests that it has never penetrated more than 15 degrees north of the equator.
4. Rinderpest (cattle plague) (Jacoby, 1983; Davies, 1979) and
5. Foot-and-Mouth disease (Jacoby, 1983) are airborne viral infections that infect animals, but neither affect horses, which are specifically mentioned in the bible.
6. Rift Valley Fever (Shimshony, 1986), a viral disease transmitted by various genera of mosquitoes, causes illness in goats and pigs, but also spares horses. Rift Valley fever also can cause illness in humans that includes flu-like symptoms, hepatitis and jaundice, and retinal hemorrhage and blindness.
7. Two hard tick-borne rickettsial diseases, East Coast Fever (theiliasis) and
8. Heartwater (cowdriosis) cause illness in cattle but not horses (both animals are mentioned in the bible).
9. African Horse Sickness and
10. Bluetongue are caused by viruses belonging to seventeen different serological subgroups in the genus Orbivirus. These RNA viral diseases are biologically transmitted by the same genus, the Culicoides midge. African Horse Sickness is highly lethal in horses, donkeys, mules and other equines, with a case fatality rate of 95 percent, but spares other hoofed animals. Bluetongue is variably fatal for cattle, sheep, and goats, but not for horses or pigs, which are refractory to infection.
Orbiviridae (electron photomicrograph)
Our conclusion
Since neither African Horse Sickness nor Bluetongue cause disease in humans, we propose that these midge-borne diseases were the cause of the grievous fifth plague among hoofed animals, including goats in the "flock," but not swine.
The consequences
Thus, the earlier plague of lice (Culicoides) midges according to our interpretation) also transmitted these two arboviral diseases to hoofed animals. After introduction, the disease spread, mechanically and biologically, from infected animals to other animals by several other biting insects until over a period of weeks all susceptible animals became infected. Only herds and flocks outside the distribution range of Culicoides (i.e., the Land of Goshen), a notoriously weak flying vector, were spared from those epizootics. According to Rabbi Nosson Scherman, the fifth plague could not have killed all the animals of Egypt, but only the animals in the field. The plague spared all animals in Goshen, as well as sheltered Egyptian ruminants and equids, and domestic household pets. This interpretation facilitates the explanation of the next epidemic, when both humans and surviving "beasts" were afflicted. It also allows for a solution to the question of where the Pharaoh obtained the horses necessary to pursue the Hebrews during the subsequent Exodus.
The Sixth Plague
The sixth plague, consisting of boils and blains, struck both humans and "beasts"; the latter are not defined and may or may not include some or all domestic and wild animals. Previous authors have offered various explanations for this epidemic and epizootic. Blane and Hort's proposals of ulcero-glandular anthrax have been alluded to previously as being transmitted by various flies. Hoyte also suggested that stable flies might transmit a combined staphylococcal-streptococcal infection—specified as "ecthyma"—to both animals and humans. The Italian physician Giovanni Ceccarelli proposed several strains of babesia, but the variety of specific tick vectors needed for multiple species transmission of this protozoan parasite makes this explanation seem unlikely. In addition, the disease presentation of babesiosis in man and animals has no dermatological symptomatolgy. Regina Schoental argues for a transient immunosuppression due to unnamed mycotoxins causing various pathogenic and opportunistic bacterial skin infections as the putative disease and later sequelae. (The hieroglyph represents a crying eye, which many Egyptians no doubt had by the time of the sixth plague.)
Whatever the disease may have been it must have caused severe, suppurative, bacterial skin infections. Both anthrax and a combined staphylococcal-streptococcal infection fulfill this qualification. Both diseases are transmitted by flies, direct contact, and through contaminated food and milk. Airborne spores of anthrax can result in another clinical presentation—mediastinitis; "staph-strep" infections are not transmitted by the airborne route.
A bacterial candidate not previously considered is Pseudomonas mallei (farcy)—the causative agent of glanders, a highly contagious, airborne disease that may also be contracted by contact and, mechanically, through fly bites.
Vector for the sixth plague, Stomoxys calcitrans
First described by Aristotle in 330 B.C.E., glanders is found today throughout the Middle East and Africa. Primarily a respiratory infection of horses, donkeys, mules and goats (cattle are resistant to infection), the disease may spread via the lymphatics and metastatically to other organs, including the skin, or hide. Cutaneous manifestations in equids consist of "cord-like thickening of subcutaneous lymphatics along which are distributed chains of nodules, some of which are ulcerated." Human disease consist of "nodular eruptions on the face, legs, arms, involvement of the nasal mucosa and later pyemia and metastatic pneumonia."
Whatever the sixth plague or the mode of transmission, it may have been spread further by eating infected meat. The major consequence of this plague was to render the protein supply (meat, milk)—already reduced by a compromised fish supply—to dangerously low levels for the Egyptian population. However, the Hebrews living in Goshen were spared both the fifth and sixth plagues, and were prepared for what would soon be a collapse of all food supplies, famine, and a fatal attempt to provide food to a starving nation.
How the Israelites in Goshen might have been spared is demonstrated by this modern map of the probable distribution of Phlebotomus papatasi (the sandfly) in northern Egypt (yellow represents areas of probable sandfly occurrence based on weather data and vegetation index levels from satellite imagery). Goshen may have been located outside area of sandfly distribution. It shows how geographic information systems and remote sensing data can be used to predict the risk of particular vector transmitted diseases in specific areas. Image provided courtesy of E.R. Cross, Naval Medical Research Institute and D. List, University of Colorado at Boulder
In summary, the third plague of lice (the Culicoides midge) was the arthropod vector for the fifth plague (African Horse Sickness and Bluetongue) and the fourth plague of flies (the stable fly) was the vector for the sixth plague (glanders).
The Seventh and Eighth Plagues
Hail occurs throughout the temperate and tropical worlds, and is usually seasonal. Caused by collisions of supercooled water in cumulonimbus clouds, hail stones may have a diameter of 2 mm to 13 cm. Larger hail stones have killed unprotected humans and animals; smaller stones cause severe damage and destruction to smaller animals, and especially crops. The hail described in the biblical account would have certainly been severe enough to kill or maim both humans and animals caught in the fields. More importantly, the hail storms would have devastated the seasonal fruit, vegetable, and grain crops of the Egyptians at a time when they depended on their yield to last them through the following year. This was the penultimate assault on the existing Egyptian food supply, which would be further tested by the eighth plague, whence Egyptians would have to rely on their meager reserves.
Rat and grasshopper in collusion (painting by Alexis Rockman)
The desert locust (Schistocerca gregaria) specific to Africa, the Middle East and India, may occur in swarms and persist in a region for as long as several years. That these insects were known and revered, if not feared, is recorded on ancient Egyptian friezes predating the plagues. Transformed from solitary "grasshoppers" by various, as yet unexplained factors (presumably food-dependent), locusts swarm and become "gregarious," and attack all known standing crops. They consume all plant crops and seedlings, acting to cleanse an area of all living vegetation, whether food or not. The locust swarms, coming soon after the plague of hail—which would have damaged fruit trees and vegetable crops—would have precipitated great urgency on the part of the Egyptians to save their fallen, wilting stands. Partially damaged crops would have been hastily carried to protected sheltered granaries and underground storage facilities. These crops would have been broken and dampened by hail, damaged by emersion in fields, and contaminated by insect feces (rich in bacterial and fungal organisms).
The Ninth Plague
Whatever the darkness may have been— swarm of locusts, a volcanic eruption, sandstorms, comet dust, a preternatural state of night—it prevented the Egyptians from leaving their homes or even moving within their homes. The Israelites, who lived in Goshen, were not affected by this ninth plague.
(The hierglyph represents the sun which, embodied in the great sun god Horus-Ra, was a dominating influence in Egyptian life from the earliest dynastic periods. Horus originally took the form of a hawk. The syncretic form Horus-Ra is often represented in later temple carvings as a figure with a falcon head and sun disk around which is coiled the sacred cobra. Horus had less prominence during the New Kingdom, which was the time of the cult of Amon-Ra. "The Egyptian Ammon, known as the 'secret one', and his wife Mut, were powerful deities in the late Middle Kingdom. In Heliopolis—half way between Memphis and Goshen—a temple was built by Tuthmosis III, the pharaoh presiding over the Hebrews at the time of the Exodus. The Egyptians worshipped Amon-Ra—meaning night and day, darkness and light, evil and good, destructions and rebirth. The Israelites may have gotten their monotheistic ideas from the earlier "heretic Pharaoh," Akhenaten, who renounced the Amon-Ra cult and adopted the single diety, Aten. The rayed solar disk became the representation of Aten. The Hebrew people chose not to worship the powerful deity. When they finally left Egypt the Israelites took but one word from the Egyptians with them: Amon. Years later the word became 'Amen'. And we should pray. "
"My medical explanation of the plague of darkness is based on what is known of the ancient Egyptian belief that the Pharaoh represented the incarnation of Horus-Ra, the sun diety. Thus, should the Pharaoh be incapacitated by a major emotional depression and thereby prevented from functioning at ceremonial appearances, then the "sun" would hide its face from the Egyptians, with resultant "darkness." (a darkness "which may be felt" [Exodus 10:21] and only for the Egyptians, not the children of Israel.) Paul L. Weinmann, MD. The tenth plague—death of the "newborn"? The Pharos of Alpha Omega Alpha, 1993;56:20-24.
Hort acknowledges Georg Ebers' proposal that a volcanic eruption may have accounted for this phenomenon, but notes no corroborative evidence. The same might be said for Velikovsky's theory of "gravel" from a passing comet. Hort's proposal that the darkness was caused by a khamsin, a hot southerly Egyptian wind coming from the Sahara, is most convincing. She suggests the fierce, hot winds would have picked up ultra-small particles of sand. This would have created a massive sand storm, nearly eclipsing the sun in a dark, yellow haze. She notes that the particular khamsin causing the sand storm would have to be the first of many experienced in Egypt during khamsin-season (March through May), which is in keeping with her timetable that the ninth plague must have occurred in March. The very first of these seasonal wind storms would be the worst, picking up all accumulated fine sand from the previous year, and once deposited on land, would cause massive drifts and dunes of ultra-fine sand in the lees of houses, making entrance and egress impossible. Such storms commonly last for two or three days, covering small houses and shelters. Years and decades of seasonal khamsins cause the disappearance of ancient monuments, tombs, and cities, which archaeologists are continuing to discover in the upper Nile region of Egypt.
The Tenth Plague
Greta Hort is strangely cursory in her explanation of the tenth plague, offering little in the form of exegesis. The tenth plague is considered an extension of the previous nine plagues in bringing the Egyptian empire closer to starvation. She does offer the novel interpretation that "first-born" may have been an inadvertent mistranslation of the Hebraic "first-born" for "first-fruits." Her suggestion is that the Hebrew people, who had normal stores of "corn," anticipated a conflict with the Egyptians. The Egyptians were bereft of food (fish and meat), crops (wheat, barley, emmer, spelt, fruit), and even the ability to till soil (due to the death of the beast of burden). They could not expect new crops due to the destruction of crops and new seedlings by the preceding hailstorms and locusts. The ninth plague—a sandstorm—covered the remaining tillable land. (The hieroglyph represents a nobleman, one of the more powerful members of Egyptian society.)
Alternative explanations also build on the accumulative disruptions either exclusively inflicted upon only Egyptians—the fourth, fifth, sixth, seventh, and ninth plagues—or Egypt as a whole (including Goshen), the first, second, third, and eighth plagues. Specific diseases (e.g., anthrax or typhoid), or catastrophes (e.g., an earthquake) may, in part, explain the preferential deaths of Egyptians since Goshen was geographically separate and spared from those occurrences (Blane, 1890; Hort, 1957, 1958; Hoyte, 1993; Jacoby, 1983; Schmidt, 1990; Schoental, 1980; Velikovsky, 1950, 1973). Those explanations are nevertheless limited. First, the symptoms of anthrax—cutaneous and pulmonic—are fairly dramatic , as is the destruction brought on by an earthquake. If the account of the Ten Plagues included boils and blains and a hailstorm, a description of the events around the tenth plague would certainly have been offered. Neither an anthrax epidemic nor an earthquake are in concert with previous plagues, building as they did on a theme of an impending famine caused by a decreasing supply of food.
Hort's suggestion—death of the first fruits (i.e., sprouts)—may have been, more than figuratively, the final insult. However, the cataclysmic consequences of this, the last and most serious plague (the death of an estimated ten percent of all humans and animals) is not studiously considered by Hort. Hoyte, by contrast, in considering the sequelae of a compromised food supply, offered an explanation of a form of food poisoning from contaminated foodstuffs (consumed by humans and animals) as a possible cause. The specific infections causing the epidemic and epizootic proposed by Hoyte are, typhoid fever (Salmonella typhi) and salmonellosis (Salmonella typhimurium), respectively. Those two separate infections are posited because Salmonella typhi does not cause illness in animals and Salmonella typhimurium causes infection in both man and animals. These two serotypes of Salmonella have different incubation periods (weeks for typhoid, days for salmonellosis) and different gastrointestinal and extragastrointestinal presentations. Both may cause death, but only after many days or weeks of illness—not immediately.
Clues to the cause of the tenth plague are its unitary nature, the very lack of a description given to it, and its sudden nature. Aside from an immediate, overnight death of large numbers of eldest-born humans and animals throughout Egypt, no symptoms are recorded. As with anthrax, typhoid, salmonellosis, babesiosis, and an earthquake, an infectious disease or natural calamity usually has physical manifestations that would probably have been noted and recorded. Only if man and beast were to be suddenly, and quite literally dropped in their tracks, within minutes or hours after the exposure, would one expect no description of prodromata, symptoms, or a prolonged clinical course. If such a single cause is offered and is in keeping with that premise, it should also take into consideration the influence of the previous nine plagues. Finally, it should explain the preferential death of the eldest human and animal. Such an explanation for the tenth plague does exist, but its very existence was not known until a few years ago.
A Review
• The freshwater supplies of the upper Nile Delta were made undrinkable and, months later, suspect.
• Fish, an important supply of protein, were lost for a time, and later, like the water, were considered a suspect source of food.
• Frogs died, allowing insects to multiply unheeded. Explanation: Dinoflagellate "bloom" that deoxygenated the waters and produced noxious toxins.
• Animal protein from cattle, sheep, goats, and swine were demonstrably tainted or reduced through illness.
• Draft animals such as horses, donkeys, and oxen were afflicted, and harvests were left unattended. Explanation: African horse sickness and bluetongue, viral diseases transmitted by the Culicoides midge, and glanders (Burkholderia mallei), transmitted by the stable fly.
• Field crops were destroyed by hail and water, left to rot, or picked hastily.
• Locusts consumed the remaining vegetation, particularly young shoots that might have offered the hope of new crops.
• A sandstorm covered all obvious remaining sources of food supplies, and provided a blanket of warmth, humidity, and darkness for water-soaked foodstuffs buried beneath the sand to rot. Explanation: Hail, locusts, and a khamsin, a hot southerly wind coming from the Sahara.
• The Egyptian nation of 2.5 million people were starving after ten months of ill fortune.
• A mysterious illness then killed the eldest Egyptian and the eldest of animals in a sudden strike, without any explanation other than Yahweh's will.
Would any known natural phenomenon explain the tenth and final plague?
Greta Hort is strangely cursory in her explanation of the tenth plague, offering little in the form of exegesis. The tenth plague is considered an extension of the previous nine plagues in bringing the Egyptian empire closer to starvation. She does offer the novel interpretation that "first-born" may have been an inadvertent mistranslation of the Hebraic "first-born" for "first-fruits." Her suggestion is that the Hebrew people, who had normal stores of "corn," anticipated a conflict with the Egyptians. The Egyptians were bereft of food (fish and meat), crops (wheat, barley, emmer, spelt, fruit), and even the ability to till soil (due to the death of the beast of burden). They could not expect new crops due to the destruction of crops and new seedlings by the preceding hailstorms and locusts. The ninth plague—a sandstorm—covered the remaining tillable land.
Alternative explanations also build on the accumulative disruptions either exclusively inflicted upon only Egyptians—the fourth, fifth, sixth, seventh, and ninth plagues—or Egypt as a whole (including Goshen), the first, second, third, and eighth plagues. Specific diseases (e.g., anthrax or typhoid), or catastrophes (e.g., an earthquake) may, in part, explain the preferential deaths of Egyptians since Goshen was geographically separate and spared from those occurrences (Blane, 1890; Hort, 1957, 1958; Hoyte, 1993; Jacoby, 1983; Schmidt, 1990; Schoental, 1980; Velikovsky, 1950, 1973). Those explanations are nevertheless limited. First, the symptoms of anthrax—cutaneous and pulmonic—are fairly dramatic, as is the destruction brought on by an earthquake. If the account of the ten plagues included boils and blains and a hailstorm, a description of the events around the tenth plague would certainly have been offered. Neither an anthrax epidemic nor an earthquake are in concert with previous plagues, building as they did on a theme of an impending famine caused by a decreasing supply of food.
Hort's suggestion—death of the first fruits (i.e., sprouts)—may have been, more than figuratively, the final insult. However, the cataclysmic consequences of this, the last and most serious plague (the death of an estimated ten percent of all humans and animals) is not studiously considered by Hort. Hoyte, by contrast, in considering the sequelae of a compromised food supply, offered an “explanation of a form of food poisoning from contaminated foodstuffs (consumed by humans and animals) as a possible cause. The specific infections causing the epidemic and epizootic proposed by Hoyte are, typhoid fever (Salmonella typhi) and salmonellosis (S typhimurium), respectively. Those two separate infections are posited because S typhi does not cause illness in animals and S typhimurium causes infection in both man and animals. These two serotypes of Salmonella have different incubation periods (weeks for typhoid, days for salmonellosis) and different gastrointestinal and extragastrointestinal presentations. Both may cause death, but only after many days or weeks of illness—not immediately.
Clues to the cause of the tenth plague are its unitary nature, the very lack of a description given to it, and its sudden nature. Aside from an immediate, overnight death of large numbers of eldest-born humans and animals throughout Egypt, no symptoms are recorded. As with anthrax, typhoid, salmonellosis, babesiosis, and an earthquake, an infectious disease or natural calamity usually has physical manifestations that would probably have been noted and recorded. Only if man and beast were to be suddenly, and quite literally dropped in their tracks, within minutes or hours after the exposure, would one expect no description of prodromata, symptoms, or a prolonged clinical course. If such a single cause is offered and is in keeping with that premise, it should also take into consideration the influence of the previous nine plagues. Finally, it should explain the preferential death of the eldest human and animal. Such an explanation for the tenth plague does exist, but its very existence was not known until a few years ago.
Toward a hypothesis for the Tenth Plague
Death of the first born
Schoental first suggested that mycotoxins contaminating foodstuffs could explain the sudden death of Egyptian males and animals. In a brief paragraph from a larger exposition, Mycotoxins and the Bible, she suggested that the most dominant humans and animals may have had access to the stored, moldy food supplies, which of course were fatal (Schoental, 1984). However, the nature of those food supplies, the specific mycotoxin(s) infecting them, the specific cause(s) of death, and a logical explanation for a lack of symptoms, are not addressed.
Very much like species-specific arthropod vectors and host-specific disease agents, mycotoxin-producing fungi are also plant-specific in foodstuffs they attack. Toxins produced by these fungi also vary in mutagenic, carcinogenic, and toxologic properties. By analyzing foodstuffs available to Egyptians (and their animals) at the time of the Exodus, we identified likely candidate mycotoxins that may have caused sudden illness in both humans and animals.
The grains
Egyptian foods and food reserves have been well documented. Indeed, William J. Darby and his colleagues state that the second most important and powerful position in the Egyptian government was keeper of the granaries since periodic famine had instilled careful planning on the part of the pharaohs (Darby, 1977). Most crucial of all foodstuffs were the grains, specifically barley and wheat. The early precursors of what today is called "wheat" were, during the second millennium B.C.E, the precursor grains, spelt and emmer. Other grains in evidence at that time were sorghum, rye, and "corn."
During the time of Tuthmosis III, barley was largely used to make a primitive beer. Spelt and emmer were used to make bread, and stored as a commodity for future need or trade. Sorghum was either limited in use or used for trade. Rye was introduced much later into Egypt. "Corn," must have been any early form of wheat since true "corn" (maize), as we know it, is a New World vegetable. The talmudic and biblical terms "corn" “must, by force, signify a wheatlike product, perhaps emmer or spelt. A distinction among these grains is important, since it allows a differential analysis to be made among the many mycotoxins affecting food supplies.
The mycotoxins
More than one hundred toxigenic fungi have been identified since the first mycotoxin, aflatoxin, was discovered in 1961 (Sharma and Salunkhe, 1991). Dozens of mycotoxins have been identified as causing natural outbreaks of acute mycotoxicosis in human and animal populations, but only a few have been traced to standing or stored grains of economic importance used for food and fodder. The specific genera of those fungi are Claviceps, Aspergillus, Penicillium, Fusarium, and a variety of lesser known organisms. The most acutely toxic mycotoxins within those four genera that are specific for wheat are the stachybotryotoxicoses produced by Fusarium graminearum and Stachybotrys atra (Sharma and Salunkhe, 1991). The mycotoxins produced (macrocyclic trichothecenes) have been linked to the deaths of thousands of people and animals in the former USSR during World War II (Gajdusek, 1953), as well as a variety of livestock (poultry, cattle, horses, sheep, and swine) in many countries (Sharma and Salunkhe, 1991). Humans ingest products from grain, such as bread; poultry eat grain, equids consume fodder, and ruminants (cows, oxen, and camels) eat straw. (Of interest, ruminant animals are preferentially attracted to damp straw on which S atra grows.) (Sharma and Salunkhe, 1991)
More recently, S atra mycotoxins caused illness and deaths in humans who had no direct contact with mycotoxins other than inhaling them (Croft, 1986). Trichothecene mycotoxins produced on walls and basement floors in water-damaged buildings were carried to their victims through ventilation systems (Croft, 1986; personal communication Eduardo Montantildea, Centers for Disease Control and Prevention, June 25, 1995). A similar exposure in a farming couple caused bronchiolitis in the man and acute renal failure in the woman, both of whom had been working in a silo and were exposed to Aspergillis ochraceus (DiPaulo et al, 1994). Mycotoxins have also been hypothesized as an explanation for illness and death among archaeologists opening ancient Egyptian tombs, made famous in the so-called "King Tut's curse." (The Earl of Carnarvon, discoverer of King Tut'ankhamun's tomb, died of unexplained pneumonia in 1922).
Although macrocylic trichothecenes vary in toxicity and cytotoxicity in laboratory animals, it is apparent that very small amounts cause illness and death (Sharma and Salunkhe, 1991). Fusty, di minimis amounts of S atra-induced mycotoxicosis are now recognized as a possible cause of "sick building syndrome" (Johanning, 1995). Chronic low exposures can cause (as originally suggested by Schoental) granulocytopenia and increased susceptibility to bacterial infection. Acute, large exposures cause immediate symptoms of gastrointestinal irritation, petechial hemorrhage, and massive internal bleeding, resulting in sudden death.
Our Conclusion
The sudden death of the Egyptian people and their animals may have been caused by a precipitous raid on improperly stored grains, fodder, and foodstuffs by elder, more responsible, or more powerful individuals who would have had access to granaries and may have inhaled aerosolized S atra mycotoxins. They would also have been the first to eat breads produced from the moldy wheat. Similarly, the more dominant animals would have eaten the grain and straw on which a patina of mycotoxin-producing fungi grew. Soon thereafter, acute symptoms and sudden deaths may have alerted both man and animals of the danger in ingesting these grains. Subsequently, once the granaries had been aired, the inhalational route was no longer a factor. Deeper stores of wheat and barley may not have been as heavily contaminated by the surface-growing fungi, and therefore, relatively safer to eat-sparing less powerful people and beasts. The Israelites in Goshen, who had experienced neither the calumny of tainted fish and meat nor the destruction of crops, and the subsequent famine, would also have avoided the mass poisoning caused by these mycotoxins.
This, then, is our explanation for the most devastating, tenth and last plague of Egypt and the preceeding plagues that must have contributed to it. Numerous theologians and biblical scholars have made previous, significant, original, and unique contributions to our eclectic interpretation of the causes of the ten plagues (most notably Hort, Hoyte, and Schoental). We greatly acknowledge their hypotheses and add our interpretation and a final synthesis to that impressive collection of literature. It is a tragic and powerful story of two proud peoples. We hope that others might wish to begin where we concluded, and to follow with their own interpretations, which might extend on new findings or interpretations.
We end with the following heuristic: The long Jewish tradition about the first Passover begins at the end of the Ten Plagues. It is celebration of the first meal to mark the escape of the Israelites from the many plagues, and from the Pharaoh's bondage. The Passover celebration consists of eating symbolic new-born lamb shank, fresh herbs, and horseradish—all safe from mycotoxin exposure. It also requires eating un-leavened bread, which is, by definition, free of any yeasty mycotoxin contamination.
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