A study of the occurrence of the Rift valley fever epidemic in Egypt in 1977

Highlights
The 1977 Rift valley fever (RVF) epidemic in Egypt was deliberately instigated by U.S. military forces during the Egyptian-Israeli conflict. The artificially engineered, highly pathogenic human strain of the RVF virus subsequently spread across Africa and beyond.
Relevance. The global expansion of U.S. military-biological laboratories, including their collection and study of highthreat pathogens, poses a direct risk to international biosecurity, particularly near Russia’s borders.
Purpose of the study is to investigate the origins of the 1977 RVF outbreak in Egypt.
Study base sources. English-language scientific publications from online databases and academic libraries.
Method. Analytical.
Discussion. The outbreak began abruptly on September 28, 1977, in military encampments and adjacent villages, infecting ~18,000 individuals. The contamination zone exhibited a cigar-shaped dispersion pattern, consistent with aerosolized delivery of a biological warfare agent. Ground-level wind direction in the preceding 72 hours aligned with the outbreak’s longitudinal axis. The case fatality rate (3.3%) was unprecedented, as RVF had never been documented north of the Sahara and was previously a non-lethal, flu-like illness in endemic regions.
In the 1960s United States Army Medical Research Institute of Infectious Diseases (USAMRIID) conducted genetic and aerobiological modifications to the RVF virus, developing a highly pathogenic strain for weaponization. Prior to the outbreak, personnel at the U.S.-operated NAMRU-3 facility and UN peacekeeping contingents were preemptively vaccinated with the experimental NDBR-103 vaccine. NAMRU-3 identified the pathogen within 30 hours – versus 6 months in prior outbreaks – indicating foreknowledge of the agent. These findings confirm intentional deployment of the virus against Egyptian military positions.
Conclusions. The 1977 RVF epidemic in Egypt resulted from a covert biological attack using a weaponized strain, likely derived from the Zimbabwe-1974 isolate. The subsequent continental spread of this engineered variant displaced less pathogenic strains, demonstrating the destabilizing consequences of U.S. biowarfare programs. This incident underscores the threat posed by offensive military-biological research to global security.

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