Some of the Wuhan coronavirus (COVID-19) vaccines currently in development could increase recipients’ risk of developing HIV infection, a new study published in The Lancet suggests.

Researchers say efforts to create an HIV vaccine more than a decade ago did the same thing, and now it is happening all over again as governments and drug companies rush to produce a jab that will get the world back to “normal.”

These HIV vaccines of old contained a modified virus known as adenovirus 5 (Ad5) that was supposed to function as a vector to transport some of HIV’s genetic material into the body for immune purposes. Problems arose, however, when Ad5 started to infect people with HIV directly.

There are currently four COVID-19 vaccine candidates in the running around the world that use similar technology, including one in the United States, as well as one in Russia and another in Pakistan. Another had been in the works in Australia as well until trail participants there started to test positive for HIV.

Researchers warn that Ad5 could increase the risk of HIV infection, and drug companies and governments need to be aware of this. Informed consent for such vaccines, should they be tested and released, need to reflect the “considerable literature” that exists concerning the risk of HIV acquisition with Ad5 vectors.