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Questions and Answers: The 15% Increase in HIV Diagnoses from 2004-2007 in 34 States and General Surveillance Report Questions |
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- CDC’s new HIV/AIDS Surveillance Report shows that from
2004-2007, HIV diagnoses increased 15% in the 34 states that have
long-term, name based HIV reporting. Why?
There are four main
reasons that could explain the increase in diagnoses. - The
increase in new diagnoses may be due to changes in state
reporting regulations.
- Several states have revised their HIV reporting laws to include
laboratory reporting of all viral loads and CD4s. This may have lead to more
complete reporting of new diagnoses as well as identification of prevalent
cases of HIV that were previously unreported. As states continue to
implement revised surveillance practices, the annual numbers of reported and
diagnosed cases of HIV infection are likely to fluctuate.
- Electronic lab reporting of viral loads and CD4 counts enables states to
capture HIV cases among persons diagnosed with HIV infection who may not
have been reported when they were initially diagnosed, or that were
diagnosed prior to implementation of confidential name-based reporting in
that area.
- We cannot determine what proportion of the increase is due to changes in
regulations.
- There may be more people getting tested for HIV, which could
result in more new diagnoses.
- There has been increasing
emphasis on the benefits of increased HIV testing among
persons at high risk which may have lead to an increase in
HIV testing, and therefore an increase in diagnoses reported
to surveillance systems, among various populations and in
certain states. Increases in HIV testing may have also
resulted from broader use of rapid HIV tests and changes in
testing practices following publication of CDC’s guidelines
for routine HIV screening in health care settings in 2006.
More HIV testing may have lead to more diagnoses (i.e., a
decrease in undiagnosed infections, which we saw with the
release of the recent HIV prevalence data).
- CDC has
emphasized HIV testing since the release of its 2006 testing
guidelines and has a number of efforts to increase testing,
e.g., increasing testing efforts among African Americans and
working to implement routine HIV testing in healthcare
settings. Therefore, it is not unrealistic to think that
more people are getting tested, which could lead to more HIV
diagnoses.
- An MMWR published in October 2008 showed that testing rates are higher
for pregnant women, persons who acknowledge HIV risks, young persons (ages
18-34), and African Americans than other groups. This suggests that testing
efforts have reached many of the people disproportionately affected by HIV.
- The increase in new diagnoses may be linked to instability
in the data.
- The increase appeared mostly in the last
year of reporting (2007).
- Due to some uncertainty inherent in statistical
estimates, the estimated data for the most recent year is
always the least stable.
- There may actually be an increase in new HIV infections.
- The surveillance report notes, “…it is not possible to rule out a rise
in HIV infections since the estimation models include a degree of
uncertainty. Moving forward, data from CDC’s new HIV incidence surveillance
system will provide the best indication of changes in new HIV infections.
Data on trends in new HIV infections will be available after at least three
years of data have been reported from the new systems.”
- CDC will be better able to tell if this increase in diagnoses is due to
an increase in incidence once we have at least three years of data from the
HIV incidence surveillance system (STARHS).
- Are there increases in certain races/ethnicities, age
groups, or transmission categories that stand out, or is there an
across-the-board increase?
Increases in annual estimates of HIV/AIDS diagnoses were seen among
subpopulations.
- From 2004 to 2007, there was a 26% increase in estimated annual HIV/AIDS
diagnoses among MSM. This increase may represent an increase in HIV
incidence in MSM, which was found in the recent incidence data. It may also
be affected by increases in testing.
- HIV diagnoses among MSM increased all four years of the
analysis, with the largest increase occurring in the last year.
- Although it is difficult to determine whether the increase in
diagnoses represents a true increase in incidence, a recent CDC analysis
indicated that HIV incidence among gay and bisexual men has been
increasing since the early 1990s.
- Additional years of data from CDC’s incidence surveillance
system will allow us to determine whether these increases have
continued.
- During this same period a 9% increase in annual diagnoses was seen among
male high-risk heterosexuals, and a 14% increase among females.
- Additional incidence surveillance data will allow us to determine
whether these increases represent increases in incidence or are due to
the other factors outlined in question #1.
- There were increases in annual diagnoses among all racial/ethnic groups.
- Again, future years of incidence surveillance data will allow us to
determine if the increases represent increases in incidence or are due
to the other factors outlined in question #1.
- The report says that HIV diagnoses have increased among people
50 and older. Does this mean HIV is increasing among older
Americans?
It should not be concluded that the annual number of new HIV
infections among older Americans is increasing based on HIV
diagnosis data alone. HIV diagnosis data should be interpreted with
caution as some persons may have been infected recently while others
were infected many years ago. However, an increase in routine HIV
screening could account for an increase in HIV diagnoses. Data from
the HIV incidence surveillance system (after at least 3 more years
of reporting) will provide answers to this question.
- What do HIV diagnoses data tell us that cannot be discerned from
incidence data?
Estimates from CDC’s new HIV incidence surveillance system
provide the clearest picture to date of new infections (HIV
incidence), both overall and among the most affected populations.
However, HIV diagnosis data are needed to provide a measure of the
burden of disease, testing, prevalence, and treatment/care needs.
- HIV diagnosis data, in conjunction with HIV incidence
estimates, will provide information to help evaluate efforts to
increase the proportion of HIV-positive individuals who are
tested and aware of their status.
- HIV diagnosis data also allow us to evaluate efforts to
improve early HIV diagnosis, as data on concurrent HIV and AIDS
diagnoses provide an indication of the proportion of individuals
being diagnosed late in the course of their disease.
- HIV diagnosis data also provide a picture of the current
burden of disease (HIV prevalence), as they indicate all
individuals who have been diagnosed with HIV infection and/or
AIDS.
Also, despite the potential limitations of using HIV diagnosis
data as a proxy measurement for HIV incidence, data on HIV diagnoses
continue to provide the best information on the distribution of HIV
infection in
- areas that do not collect data for HIV incidence
surveillance;
- areas without sufficient incidence data;
- smaller populations (such as smaller racial/ethnic groups),
in which it may not be possible to generate reliable HIV
incidence estimates;
- young people, ages 13-24, due to their recent infections.
- From 2004-2007, how many states were added to the name-based HIV
reporting system? How does this addition affect the data? Would
this/these additions account for the 15% increase?
Georgia was added to the tables for estimated HIV/AIDS,
increasing the number of states included in these analyses from 33
to 34. Cases from Georgia did contribute to the increase seen from
2004 to 2007; however, the addition of Georgia alone did not result
in the increase. Estimates of annual diagnoses in Georgia increased
10% from 2004 to 2007; however, numerous other states, including a
few with higher HIV morbidity (e.g., Florida, New York) showed
increases in annual estimates.
States are added to tables for estimates of HIV/AIDS after
sufficient time (at least 4 years of confidential name-based
reporting) has passed in order to allow for stabilization of
reporting, calculation of reporting delay weights, and more accurate
interpretation of trends.
- Are there state or regional increases in HIV diagnoses, or is
the increase evenly distributed across the country?
Increases were seen in 28 out of the 34 states.
- What do we know about trends in the South (if not based on
HIV data – then what do we know based on AIDS data)?
Increases
were seen in most (12/13) of the southern states for which
estimated HIV diagnosis data is available (13/17). We do not
provide annual estimates of HIV/AIDS, by region, in the annual
report. AIDS data should not be used to evaluate trends in HIV
infection as AIDS diagnoses are a result of missed opportunities
and/or failed treatment. However, looking at the data by region
from 2003 to 2007, the estimated number of AIDS cases decreased
5% in the South.
- The 15% increase covers years 2004-2007. Was there an increase
in diagnoses in each year?
The annual number of HIV/AIDS diagnoses remained stable from 2004
through 2006. A 15% increase in annual HIV/AIDS diagnoses from 2006
to 2007 accounts for the majority of the increase seen from 2004 to
2007. As we know, the most recent year of data is the most subject
to change as the estimation models include a degree of uncertainty.
- The surveillance report says that AIDS cases have decreased.
Why? It also says that AIDS deaths have decreased. Why?
AIDS cases have decreased due to widespread use of highly active
antiretroviral therapy which prolongs the time from diagnosis with
HIV infection to progression to AIDS.
Estimated deaths among persons with AIDS have most likely
decreased as a result of HAART. As HAART increases the time from
diagnosis with HIV infection to progression to AIDS it also extends
the lifespans of persons with AIDS.
PLEASE NOTE FOR ALL DEATH- RELATED QUESTIONS: It is
believed that the decrease seen in annual deaths from 2004-2007
among persons with AIDS is real; however, the extent of the decrease
may be overemphasized due to delays in reporting of deaths in the
most recent year(s) to CDC. CDC is currently re-evaluating its
protocols for reporting deaths in order to provide a more accurate
picture.
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