Saturday, July 12, 2003

CDC says IDU HIV rate "leveled;" Reuters says rate "rose"

A new HIV study from the Centers for Disease Control and Prevention was released on July 11, rife with findings about either declines or a leveling of new HIV infections detected among injection drug users (IDUs).

Published in the Morbidity and Mortality Weekly Report, the study’s “findings indicate that HIV diagnoses among IDUs have leveled in the majority of demographic groups during this period [1994—2000] in the 25 states for which HIV surveillance data are available.” [1]

The CDC study found that “IDU-related HIV diagnoses declined from 4,226 case in 1994 to 2,403 cases in 1999, and leveled to 2,514 …[in] 2000.”

In terms of raw numbers, that’s an increase of diagnoses, but, for epidemiologic purposes, the researchers deem the statistics to have leveled.

Broken down by gender, male IDU diagnoses “declined 44%, from 2,819 in 1994 to 1,568 in 1999, and leveled to 1,628 in 2000,” while the rate for female IDU diagnoses “declined 41% from 1,407 in 1994 to 835 in 199, and leveled to 886 in 2000.”

I found it fascinating that the researchers qualified marginal increases as a leveling, not a rise, per se.

The editorial note accompanying the MMWR article said the “finding of overall declines in new HIV infections among IDUs in the 25 states with HIV infection reporting is consistent with studies that suggest a decline in new HIV infections among IDUs in other areas of the United States.”

The CDC study provided a citation for this claim, and I located the abstract from another study from which the citation came.

The earlier study, published in the American Journal of Public Health, titled “HIV incidence among injection drug users in New York City, 1992-1997: evidence for a declining epidemic,” made the following conclusion.

“The recent incidence rate in New York City is quite low for a high-seroprevalence population of injection drug users. The very large HIV epidemic among injection drug users in New York City appears to have entered a ‘declining phase,’ characterized by low incidence and declining prevalence. The data suggest that very large high-seroprevalence HIV epidemics may be ‘reversed,’” it noted. [2]

Many reasons are likely responsible for the drop reported in the CDC study.

“Because the peak of infections occurred in the early 1990s, the decline during the late 1990s might reflect the natural decline in the epidemiologic curve following the peak in the epidemic, which often is observed after the onset of a disease in a population,” and might be one of the factors behind the decreases, stated the MMWR.

In other words, HIV transmissions hit a high among injection-drug users a decade ago. This is good news in my estimation.

What could be responsible for the slight numerical increases in 2000? The answer may lie at the end of the following sentence from the study.

“The leveling of IDU-related HIV diagnoses during 1999—2000 for the majority of demographic groups might represent a plateau in IDU-related HIV diagnoses or changes in testing behavior among IDUs.”

Translation: more IDUs may have sought out HIV testing services and taken an HIV antibody test.

Indeed, the MMWR states: “Although testing patterns can change the number and trends of new diagnoses, surveillance methods being developed by CDC will enable estimation of patterns in HIV-infection incidence.”

Even taking into account variations in testing patterns, this new CDC study and the declines or level rates contained therein cannot be dismissed, and, in my opinion, should be characterized as a positive development in containing HIV.

But despite the repeated use of the words declines, decreases and leveled, it did not stop the Reuters news wire from putting out a story about the study with this headline: “HIV diagnoses rise among intravenous drug users in US.” [3]

Reuters reporter Paul Simao wrote, “The number of new HIV diagnoses among intravenous drug users in the United States rose in 2000, halting five years of steady declines, according to a federal study released on Thursday.”

Not once in his story did Simao note how the CDC study defined the incremental increases of HIV rates for IDUs as leveling.

Simao’s Reuters story did note one of the CDC researchers “said the increases in diagnoses could have resulted from expanded AIDS [sic] testing or a change in risk behavior among intravenous drug users.” However, Reuters should have provided a larger context in its wire story about the overall leveling of HIV diagnoses in this population.

This new study comes one year after the CDC released another study on overall HIV diagnoses in 25 states, in which the authors reported similar good news.

“The number of persons in whom HIV infection without AIDS was the initial diagnosis declined 21% (from 15,945 in 1994 to 12,612 in 2000), and the number of persons in whom HIV infection with AIDS was the initial diagnosis declined 31% (from 5,760 in 1994 to 3,987 in 2000). However, during 1998--2000, the number of diagnosed cases of HIV infection with and without AIDS remained constant,” stated the July 12, 2002, article in the MMWR. [4]

Last year’s study also found that data “from national surveys and publicly funded counseling and testing sites indicate that testing rates have remained relatively unchanged during the late 1990s.”

This means that the number of initial HIV diagnoses declined, while the number of tests performed stayed constant, so the HIV rate didn’t drop because of a decrease in antibody tests administered.

Not only do we have two CDC studies documenting significant decreases or a leveling of new HIV diagnoses nationally, we also have the San Francisco Department of Public Health’s recent monthly sexually transmitted disease report showing declines of new HIV diagnoses. [5]

Too bad these developments aren’t widely reported in either the mainstream or gay press, but that lack of press coverage won’t deter me from sharing the good news about declining HIV diagnoses, if and when I find it.



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