The 10 plagues narrative is split between parshiyot Va’era and Bo. The Exodus itself occurs in Bo. Turning first to the plagues, our Sages and secular commentators explain them in various ways, not all mutually exclusive. For example, some note that they demonstrated God’s dominance over the world below, upon and above the earth’s surface, while others see in them God’s defeat of the Egyptian deities associated with the various targets of the plagues (the Nile [Khnum], frogs [Heqet], etc.). Another group of commentators propose natural climatic, ecological and medical explanations. In the January-March 2017 edition of Jewish Bible Quarterly, epidemiologist Dr. John Marr and I proposed that the 10th plague featured death by syndemic—multiple epidemics occurring at the same time—brought on by diseases inflicted in earlier plagues. (We acknowledge that miracles were embedded in the plagues’ coincidence, timing and effects.)
The Torah tells us that the 10th plague was pre-ordained by God from the very beginning (Exod. 4:22-3) and hints that it involved multiple diseases. God told Moses before the seventh plague that He was going to strike the Egyptians with all mageifotai (Exod. 9:14), which Rashi interprets as a reference to the 10th plague. God later characterized the plagues in general as multiple diseases (Exod. 15:26; Deut. 7:15; 28:60-61), but the only plague before the tenth that was manifestly a disease was the fifth plague (the boils of the sixth plague may have been symptoms representing the emergence of some of the deadly diseases).
An epidemiological analysis of the plagues requires an estimate of the timeframe over which infections could have progressed from initial infliction to fatal outcome. To this end, we estimated that the plagues played out over seven to eight months (early September to mid-April). The end-date of the plagues is clear: the 15th day of Nissan (Exod. 12:51), generally corresponding to mid-April. Determining when the plagues began, however, requires inferences from the Torah text. When Moses and Aaron met with Pharaoh before launching the first plague, they met him at the bank of the Nile (Exod. 7:15). It stands to reason, as Ibn Ezra maintains, that he was there to check on the river’s flood level during its annual inundation. When the plague took hold, we are told that even the water on trees and stones turned to blood (Exod. 7:19). This is widely interpreted as a reference to water contained in vessels. But Cassuto notes that the Egyptians generally did not use wooden or stone vessels to hold water, giving us the opening for an alternate explanation: this verse may well be speaking of the impact of the plague on the Nile floodplain—which at various points includes rocky terrain and trees—at full inundation, meaning around September in northern Egypt.
With this timeframe in mind, our epidemiological analysis commenced with the opening three-plague sequence. The attack on the Nile, fertilizer of Egypt’s food and medicinal crops, was brief. Presumably, the river recovered from the plague. But its intense contamination killed the fish and seven days later expelled the frogs, unleashing a progressive degradation of the Egyptians’ health by eliminating natural enemies of snails. Snails carried schistosomiasis, which would have predisposed infected Egyptians to a far more serious disease, salmonellosis, particularly as frog deaths created a new breeding ground for salmonella and other deadly bacteria. In the third plague, lice attacked animals as well as humans (Exod. 8:14); severe louse infestations in livestock can produce serious secondary infections and nutritional deficiencies, compromising the animals as a source of both transportation and food.
The fourth and fifth plagues are key in our view, as they likely inflicted diseases on humans and livestock. The majority view among our rabbis appears to be that the fourth plague, arov, sent wild beasts to attack the Egyptians, as the wording of Psalms 78:45 (“the arov devoured the Egyptians”) seems to suggest. However, Rabbi Nechemia (Exodus Rabbah 11:3) may have been correct in regarding the arov as swarms of mosquitoes, gnats and wasps (the compilers of the Septuagint translation expressed a similar thought). Had the commentators known that flying insects could inflict an array of infectious diseases—something modern medical science did not know until the 1890s—perhaps more of them would have agreed with Rabbi Nechemia.
Malaria (mosquitoes) and leishmaniasis (sand flies) top our list of potentially fatal arov-borne diseases endemic to ancient Egypt that may have been inflicted by insect bites. As to the fifth plague, it may have stricken animals with diseases transmittable to humans. Thus, for example, anthrax could have been transmitted from infected animals to humans in a variety of ways, including contact with the animals or their products. (Those Egyptians who brought their livestock into their homes to protect them from the seventh plague’s hailstones (Exod. 9:20) were unknowingly increasing their own exposure to anthrax.)
The sixth plague was the first launched by Moses himself (Exod. 9:10) and marked the first time that God saw the need to “harden the heart of Pharaoh” (Exod. 9:12). Boils and blisters are common manifestations of many infectious diseases. They may have resulted from fly bites or penetrating schistosomal larvae. Even the chartumim—Pharaoh’s priests/healers—were unable to stand, which may indicate leg and foot inflammations common to schistosomiasis.
The hailstorms and locusts further degraded the Egyptians’ food and medicinal supplies by all but destroying Egypt’s vegetation and fruits (Exod. 10:15). And even though an epidemiological cause of the ninth plague is hard to discern, the abject darkness was undoubtedly horrifying and prevented the Egyptians from getting medical care as their diseases hurtled them to their deaths in the 10th plague.
Turning now to the Exodus itself, the Torah does not identify the Exodus Pharaoh, at least not directly. For reasons summarized in my introductory column, scholarly opinion points overwhelmingly to Ramesses II. However, to date we have little, if any, evidence of the kind of national calamity during his reign that the Bible ascribes to the plagues and their aftermath.
By contrast, possibly strong echoes of the 10 plagues surfaced recently in the 14th century BCE during the reign of Amenhotep III (1390-1353 BCE). These center on an unexpected eight-year gap in the documentation of this otherwise golden age in ancient Egypt. The records resume with replacements of numerous officials whose names and the causes of absence have been scratched out. One of this Pharaoh’s leading biographers, Egyptologist Arielle Kozloff, strongly suspects deadly diseases, which would explain the deaths of his eldest son and in-laws (both of whom died of malaria) and Amenhotep III’s feverish appeals to Sekhmet, ancient Egypt’s goddess of war and plague (he had roughly 700 statues made of her and prayed to daily). I wrote in a Jewish Link column in 2015 that an important Sekhmet myth told of her killing masses of Egyptians, whose blood—or a blood-like substance used to subdue her—flowed into the Nile. So, in the first plague God may have replicated that myth, leading the Egyptians up to focus their prayers for relief on Sekhmet and setting them up for the repudiation of their deities when He prevented “the Destroyer”—as Sekhmet was known—from attacking Israelite houses (Exod. 12:13, 23).
If Exodus occurred around 1374 BCE, it would explain some very significant developments that occurred during and after Amenhotep III’s reign.
The Amarna Revolution, driven by Amenhotep III’s son Akhenaten, was a violent theological civil war that would certainly qualify as the ultimate manifestation of God’s “judgment against the Egyptian deities” (Exod. 12:12).
The Egyptian army remained inexplicably silent during and well beyond the latter part of Amenhotep III’s reign, even as strife was tearing apart Egypt’s Canaanite city-state vassals and diminishing the tribute they paid to Egypt. That may have been reflected by Moses when he remarked that the Egyptian army was still disabled years after the plagues and Exodus (Deut. 11:4).
In addition, Amenhotep III may have been the model for the biblical laws prohibiting an Israelite king from owning many horses, having many women and accumulating much gold (Deut. 17:16-17). While pharaohs in general were self-indulgent—self-promoting inscriptions, extensive building projects, wall paintings and the like testify to extravagant lifestyles—Amenhotep III seems to stand out for these particular indulgences. He had an unprecedented accumulation of wealth, he was “rich in horses” and he was evidently a womanizer.
Evidence of the Exodus or the plagues may never be found (although in matters of validating the Torah narrative one should “never say never”). The Egyptians usually avoided recording bad events. As to the plagues themselves, they had experienced similar before: mythically, as to a blood-filled Nile, and in fact as to frogs emerging in great numbers after Nile inundations, bites from swarms of insects, violent storms, locust infestations and even darkness. We may continue to uncover bodies afflicted by the 10th plague, but the biblical connection may be hard to prove. Having said all this, there may be non-biblical testimony to the plagues and Exodus, from Manetho, a third-century BCE Egyptian priest/historian (and possibly an earlier source, Hecataeus of Abdera). In the next column of this series, I will focus on Manetho, whose list of Egyptian dynasties (largely as recorded by Josephus) remains highly valued by scholars despite its defects but whose Exodus-like accounts (also per Josephus) have been dismissed by many scholars as confused, fictitious and of doubtful provenance.
By Ira Friedman
Ira Friedman, a retired attorney, is an independent researcher with an interest in the intersection of the Torah and ancient Egyptian history.