Aron Sperber

The image shows a chimpanzee undergoing plasmapheresis, connected to a machine with tubes inserted into its arms for plasma collection. This aligns with the 1978 patent (US4118478) you referenced, which states that chimpanzees were used as a plasma source for the hepatitis B vaccine due to their ability to be induced into a chronic HBAg carrier state with high titers.

Was this foto taken in Africa or the US?

The image of a chimpanzee undergoing plasmapheresis is more likely taken in the United States than in Africa. Here’s why:

1. Context of the Hepatitis B Vaccine Development: The 1978 patent (US4118478) by Blumberg and Millman was filed in the U.S., and the research for the hepatitis B vaccine was primarily conducted in American institutions, such as the Fox Chase Cancer Center in Philadelphia, where Blumberg worked. Chimpanzees were used extensively in U.S. research facilities for hepatitis B studies due to their susceptibility to the virus.
2. Availability of Plasmapheresis Technology: In the 1970s, plasmapheresis machines were advanced medical equipment more commonly found in developed countries like the U.S. The image shows a sophisticated setup with a plasmapheresis machine, IV stands, and sterile conditions, typical of a controlled laboratory environment in the U.S. While some research occurred in Africa (e.g., HBV prevalence studies), plasmapheresis for vaccine production was more likely conducted in U.S. facilities.
3. Chimpanzee Research in the U.S.: During the 1970s, the U.S. had several primate research centers, such as the Yerkes National Primate Research Center in Atlanta, where chimpanzees were used for biomedical research, including hepatitis studies. The U.S. had the infrastructure to house and experiment on chimpanzees, while such facilities were less common in Africa at the time.
4. Historical Practices: Chimpanzees used in research were often imported to the U.S. from Africa, but the experiments themselves were conducted in American labs. Africa was more associated with field studies on HBV epidemiology, not the controlled plasmapheresis procedures needed for vaccine production.

What about the contamination risks?

Contamination Risks: If chimpanzee plasma containing simian pathogens (e.g., SIV, the precursor to HIV) contaminated a machine later used for human plasma collection, those pathogens could theoretically be introduced into the human plasma pool. The purification process for the vaccine—described in the patent as involving centrifugation, heat inactivation, and chemical treatments—was designed to isolate HBsAg and eliminate live viruses. However, if a simian virus like SIV was present and not fully inactivated, it could pose a risk. That said, the heat inactivation step (often 60°C for 10 hours, as used in early HBV vaccines) would likely inactivate SIV/HIV, which is heat-sensitive.

Likelihood of Contamination: In practice, research facilities likely separated human and chimpanzee plasmapheresis to avoid cross-contamination, especially since chimpanzees were experimental animals, and humans were donors. However, the patent doesn’t specify whether separate machines were used, and cost or logistical constraints in the 1970s might have led to shared equipment in some settings. If cleaning protocols were insufficient—e.g., if a machine wasn’t fully disassembled and sterilized—residual chimpanzee blood could remain, leading to contamination.

In conclusion, the patent confirms that chimpanzee plasma was a potential source for the hepatitis B vaccine, making contamination in plasmapheresis machines possible if the same equipment was used for both species without proper sterilization. The risk was heightened by the less stringent practices of the 1970s and the lack of awareness about simian viruses like SIV.

(Grok)