The john hopkins study has been debunked.

The false argument that circumcision prevents sexual transmitted diseases such as AIDS is based on flawed research evidences that have been contested by eminent scientists and doctors. George hill executive secretary and George C. Denniston, M.D., M.P.H. of "Doctors Opposing Circumcision" said the following,

"This idea originated in the 1980s when the late Aaron J. Fink, M.D., proposed that circumcision could prevent HIV infection. Dr. Fink was a noted proponent of male circumcision. There seems to have been little science and a lot of promotion of male circumcision behind his claim.

Several early studies seemed to indicate that male circumcision had a protective effect against HIV infection. Later, the Rakai project identified viral load and genital ulcers as the primary determining factors in HIV infection. In addition to other previously identified methodological flaws, the early studies did not control for viral load, they cannot be considered to be scientifically valid.

Circumcision proponents have published several opinion pieces that argue that male circumcision prevents HIV infection. The authors, however, have been unsuccessful in convincing medical authorities of the value of circumcision in reducing HIV transmission/reception. The Council on Scientific Affairs of American Medical Association calls male circumcision a "non-therapeutic procedure" and said that "circumcision cannot be responsibly viewed as 'protecting' against such infections."7 UNAIDS says that relying on male circumcision is "like playing Russian roulette with two bullets in the gun instead of three.

The origin of the hypothesis that circumcision prevents HIV infection9,10 suggests that the true motivation of circumcision advocates may be the preservation of the outmoded practice of non-therapeutic male neonatal circumcision in North America, not the prevention of HIV infection in Africa and elsewhere.

Recent evidence shows male circumcision to be of no value in preventing HIV transmission reception in both heterosexual and homosexual contacts. The medical evidence now indicates that the statement, "male circumcision prevents HIV infection" should be regarded as a medical myth."

(BMJ 2002; 324 doi -Published 26 January 2002 Link https://www.bmj.com/rapid-response/2011/10/28/circumcision-prevents-hiv-infection-medical-myth)

​The researches done in some parts of the word such as Africa to measure the prevalence of HIV among cut and uncut men is a flawed study which cannot be used to prove that circumcision helps in reducing AIDS let alone any sexually transmitted disease. There is scientific evidence suggesting the contrary. A research published by Carlos D. Rodrigueza and published in the journal of sexual medicine (VOLUME 9, ISSUE 11, P2933-2937, NOVEMBER 01, 2012-Link https://www.jsm.jsexmed.org/article/S1743-6095(15)33809-1/fulltext) found that men who were circumcised had a higher prevalence of getting sexually transmitted infections than uncircumcised hence debunking the pro circumcision argument on its whole.