Youngest person sexually infected with HIV? How are pre-teens infected?

“Teenaged boy contracted HIV through intercourse — A 13-year-old boy has become the youngest patient to contract HIV through sexual intercourse, health officials said. It is suspected the boy became infected while working part-time for a 50-year-old male, who used money to lure him into having sex, Centers for Disease Control (CDC) Deputy Director-General Lin Ting . . . said”.
This report is from China (Taiwan), but the same sort of nonsense could have come from anywhere.
The demographic characteristics of “HIV” — that is, of testing “HIV-positive” — make quite plain that “HIV” is not an infectious agent, let alone a sexually transmitted one. The evidence for that is set out in considerable detail in The Origin, Persistence and Failings of HIV/AIDS Theory, and more such evidence has been presented many times on this blog.
Consider the data from the Centers for Disease Control and Prevention from all public testing sites in the USA for the period 1995-98, as published in The Origin, Persistence and Failings of HIV/AIDS Theory [“F(HIV)” means the frequency of positive “HIV” tests, a term I used to avoid speaking about “HIV infection” or “HIV prevalence”]:

Now ask,

How did those people of various ages
become “HIV-positive”?
In particular, ages up to the teens?

At birth, babies carry antibodies generated by their mothers; 75% or more of “HIV-positive” babies got their “HIV” antibodies direct from their mothers, and lose them in less than a year; see  “Mother to child transmission of HIV and its prevention with AZT and Nevirapine — a critical  analysis  of  the  evidence” (2001) by the  Perth  Group, available at www.theperthgroup.com/monograph.html.
By age 1, let alone ages between 1 and 12, babies and young children can therefore be “HIV-positive” only for some other reason than maternal antibodies. What could that reason be?
Note that the rate of “HIV-positive” continues to decline into the early teens. That was not owing to deaths reducing the number of “HIV-positives”, because in the 1990s no appreciable number of American babies or young children were dying of “HIV disease”.
Mother-to-child “transmission of HIV”, including via breast milk, had essentially ceased in the USA by the 1990s, so the only remaining means of infection would have been sexual transmission, dirty needles, or transfusion with contaminated blood. But, again, in the USA the two latter modes were almost unheard of by the mid-1990s, and sexual transmission (via sexual abuse, of course) is incredible at such high rates.
In any case, actual “infection” by any mechanism at all could not be the reason why these pre-teens tested “HIV-positive” since the rate of “HIV-positive” declined steadily, reaching a minimum in the low teens, and could not have been owing to deaths, as already remarked.
The only feasible explanation for the manner in which “HIV-positive” varies with age from birth into the teens is that testing  “HIV-positive” represents detection of substances that are associated with physiological stress, not an infectious agent. Birth is stressful, and children become physiologically stronger as their immune systems develop increasingly for years after birth. The Perth Group has published copious evidence that “HIV” tests are sensitive to and tend to test positive in the presence of oxidative stress.
That conclusion is underscored by the fact that the same variation of “HIV-positive” with age was found in healthy African subjects:

As a number of other posts on this blog have also illustrated, the manner in which “HIV-positive” varies with age is the same wherever and whenever such data are gathered, though the exact ages of the maxima and minima vary somewhat, in particular by race.

“HIV” tests do not detect a human immunodeficiency virus,
as consideration of the tests themselves already shows:
“HIV tests are not HIV tests”.

The mistaken belief that testing “HIV-positive” represents infection by a sexually transmitted agent has led to innumerable tragedies for some uncountable number of people: for instance, being needlessly fed toxic drugs, or being incarcerated for supposedly spreading a deadly infection, or becoming depressed upon being told that one is infected.