Estimated HIV incidence, prevalence, and mortality rates among racial/ethnic populations of men who have sex with men, Florida.

Abstract

Population-based HIV incidence, prevalence, and mortality rates among men who have sex with men (MSM) have been unavailable, limiting assessment of racial/ethnic disparities and epidemic dynamics.
Using estimated numbers of MSM aged >or=18 years by race/ethnicity as denominators, from models in our prior work, we estimated MSM HIV prevalence and mortality rates for 2006-2007 and HIV incidence rates for 2006 in Florida.
Overall, the estimated MSM HIV prevalence rates per 100,000 MSM were 7354.8 (2006), and 7758.3 (2007). With white MSM as the referent, MSM HIV prevalence rate ratios (RRs) equaled 3.7 for blacks in 2006 and 3.6 in 2007 and 1.7 for Hispanics in both years (all P < 0.001). Among all MSM with HIV, the mortality rates were 199.8 (2006) and 188.4 (2007), with RRs of 5.4 for blacks in 2006 and 4.9 in 2007, and 1.6 for Hispanics in 2006 and 1.4 in 2007 (all P < 0.001). In 2006, the estimated HIV incidence rate among all MSM was 656.1 per 100,000 MSM, with RRs of 5.5 (blacks) and 2.0 (Hispanics) (both P < 0.001). A sensitivity analysis indicated that error due to misclassification of minority MSM as males who are not MSM lowered rates and RRs for all the 3 indicators but racial/ethnic disparities persisted (all P < 0.001).
The impact of HIV by each measure was greater on black and Hispanic MSM than on white MSM. Quantifying estimates of HIV incidence, HIV prevalence, and mortality rates among MSM with HIV informs HIV surveillance, prevention, treatment, resource allocation, and community mobilization.

Full text

Page 1

EPIDEMIOLOGY AND SOCIAL SCIENCE
Estimated HIV Incidence, Prevalence, and Mortality Rates
Among Racial/Ethnic Populations of Men Who Have
Sex with Men, Florida
Spencer Lieb, MPH,* Stefanie White, MPH,* Becky L. Grigg, PhD,* Daniel R. Thompson, MPH,*
Thomas M. Liberti, BS,* and Stephen J. Fallon, PhD†
Background: Population-based HIV incidence, prevalence, and
mortality rates among men who have sex with men (MSM) have
been unavailable, limiting assessment of racial/ethnic disparities and
epidemic dynamics.
Methods: Using estimated numbers of MSM aged $18 years by
race/ethnicity as denominators, from models in our prior work, we
estimated MSM HIV prevalence and mortality rates for 2006–2007
and HIV incidence rates for 2006 in Florida.
Results: Overall, the estimated MSM HIV prevalence rates per
100,000 MSM were 7354.8 (2006), and 7758.3 (2007). With white
MSM as the referent, MSM HIV prevalence rate ratios (RRs) equaled
3.7 for blacks in 2006 and 3.6 in 2007 and 1.7 for Hispanics in both
years (all P , 0.001). Among all MSM with HIV, the mortality rates
were 199.8 (2006) and 188.4 (2007), with RRs of 5.4 for blacks in
2006 and 4.9 in 2007, and 1.6 for Hispanics in 2006 and 1.4 in 2007
(all P , 0.001). In 2006, the estimated HIV incidence rate among
all MSM was 656.1 per 100,000 MSM, with RRs of 5.5 (blacks)
and 2.0 (Hispanics) (both P , 0.001). A sensitivity analysis indicated
that error due to misclassification of minority MSM as males who
are not MSM lowered rates and RRs for all the 3 indicators but
racial/ethnic disparities persisted (all P , 0.001).
Conclusions: The impact of HIV by each measure was greater on
black and Hispanic MSM than on white MSM. Quantifying estimates
of HIV incidence, HIV prevalence, and mortality rates among MSM
with HIV informs HIV surveillance, prevention, treatment, resource
allocation, and community mobilization.
Key Words: HIV/AIDS, HIV incidence, HIV prevalence, men who
have sex with men, mortality, racial/ethnic disparities
(J Acquir Immune Defic Syndr 2010;00:000–000)
INTRODUCTION
Men who have sex with men (MSM) continue to be
a priority population for primary and secondary HIV
prevention in the United States and Florida. Estimates indicate
that MSM accounted for the majority of incident and the
greatest proportion of prevalent HIV infections among
adults and adolescents aged $13 years in the United States
in 2006.1–3In Florida, which ranks third in the nation in
cumulative AIDS cases through 2007 (n = 109,524 cases, or
10.6% of the national total),4MSM have accounted for more
reported AIDS cases and HIV cases than any other behav-
iorally defined risk group every year since case reporting
beganin 1982 and 1997, respectively.5Assessing the impact of
HIV-related indicators on risk populations informs effective
allocationofresourcesforoutreach,prevention,care,andtreat-
ment. However, estimates of MSM population size are needed
to compute population-based estimates of rates of HIV
incidence, prevalence, and mortality for MSM. HIV surveil-
lance, community mobilization, advocacy, and structural
analysis of community vulnerability are likely to be enhanced
by analyzing HIV indicator rates in racial/ethnic MSM popu-
lations. As always, the dilemma is to raise awareness although
finding ways to reduce stigma.6
HIV seroprevalence rates among MSM have previously
been reported in selected US cities. In 1996, Holmberg7
reported a set of risk population estimates for the largest 96
United States metropolitan areas, including numbers and HIV
seroprevalence rates of MSM.In 2001, Catania et al8presented
such estimates for MSM in 4 cities (Chicago, Los Angeles,
New York, and San Francisco). The Young Men’s Survey,
conducted in several cycles between 1994 and 2000, tested
MSM for HIV antibody in 6 cities (Baltimore, Dallas, Los
Angeles, Miami, New York, and Seattle).9,10The National HIV
Behavioral Surveillance system tested MSM for HIVantibody
during 2004–2005 in 5 cities (Baltimore, Los Angeles, Miami,
New York, and San Francisco)11and during 2008 in 21 cities
(results for 2008 currently pending). Estimated HIV prevalence
rates among MSM in each completed study were extremely
high, compared with those in the overall US population.3,12
Black MSM typically had higher rates than white MSM in the
serosurveys.UsingasomewhatbroadrangeofMSMpopulation
estimates, where 4%–10% of each racial/ethnic group of males
were assumed to be MSM, HIV prevalence rates were estimated
for Florida and selected counties by race/ethnicity in 2006.13
Again, rates were highest among black MSM.
Estimated population-based death rates among MSM
with HIV, by race/ethnicity, have been reported in a study con-
ducted in Miami-Dade County, Florida, in 2005.14However,
such death rates have not been developed at the state level
Received for publication November 5, 2009; accepted December 18, 2009.
From the *Florida Department of Health, Tallahassee, FL; and †Skills4, Inc.,
Ft. Lauderdale, FL.
Correspondence to: Spencer Lieb, MPH, Senior Epidemiologist, Florida
Department of Health, Bureau of HIV/AIDS, Bin A09, 4052 Bald Cypress
Way, Tallahassee, FL 32399-1715 (e-mail: spencer_lieb@doh.state.fl.us).
Copyright ? 2010 by Lippincott Williams & Wilkins
J Acquir Immune Defic Syndr?Volume 00, Number 0, Month, 2010 www.jaids.com|1

Page 2

in the United States HIV incidence estimates among MSM by
race/ethnicity have been established for the United States and
selected states and cities in 2006.1,2Yet, in the absence of
reliable estimates of the MSM population size, these numbers
have not been converted to HIV incidence rates. To enable
population-based estimation of all HIV indicator rates, our
recent work established MSM population estimates (ie, rate
denominators) for Florida and each of the 16 other states in the
southern region of the United States, by race/ethnicity.15
In this report, we take advantage of our racial/ethnic
MSM population estimates for the state of Florida, in parti-
cular, by dividing them, respectively, into the number of living
MSM HIV cases, deaths among MSM HIV cases, and HIV
incidence estimates among MSMto quantify population-based
indicator rates by race/ethnicity. Epidemic dynamics are
thereby clarified to enhance HIV surveillance and other public
health purposes served by surveillance data. To our knowl-
edge, these 3 HIVindicators among MSM have not previously
been converted to rates for any state or large geographic
area. For HIV cases and deaths, we analyze data for 2006
and 2007. For estimated incident HIV infections, data are
analyzed for 2006 only, as data for earlier or later years were
not yet available.
METHODS
Definition of MSM
For MSM population estimates, we defined MSM as
males aged $18 years with a lifetime history of any male–
male sex contact. For the estimates of HIV incidence,
prevalence, and deaths among HIV cases, MSM were defined
as males aged $18 years with a history of any male–male
sex contact at some time after 1977, but before their diagnosis
of HIV or AIDS, consistent with the definition used by
the Centers for Disease Control and Prevention (CDC) for
national HIV/AIDS surveillance.16MSM who were also
injection drug users (IDUs) were counted as MSM.
HIV Cases and Deaths
HIV prevalence consisted of the number of MSM living
with HIV through 2006 or 2007 (reported cases). HIV cases
were reported through the statewide HIV/AIDS Reporting
System. HIV prevalence and mortality among those with HIV
applies to those with HIV infection at any stage of infection,
consistent with the CDC case definition.4There is only 1
database for HIV cases and AIDS cases in Florida, with no
duplicate counting of cases. An AIDS diagnosis supersedes
an HIV diagnosis, as peoplewho converted from HIV to AIDS
are counted as AIDS cases only.
Behavioral risk information was generallyobtained from
medical records and publicly funded HIV test site records.
However, reported HIV cases with no identified risk for
HIV infection were redistributed into recognized transmission
categories, based on expected results of follow-up inves-
tigations.17Deaths among reported MSM HIV cases in 2006
and 2007 were those that were due to any cause. Deaths were
reported by county and multicounty HIV/AIDS surveillance
coordinators and the state Office of Vital Statistics. Deaths
were also ascertained through matching of the state HIV/AIDS
database with the Social Security Death Index, a national
database of all decedents for whom Social Security death
benefits have been claimed.
Completeness of reporting of Florida HIV cases and
AIDS cases is estimated at approximately 95%, that is,
approximately 95% of these cases are ultimately reported.
Greater than 95% of HIV cases and AIDS cases reported in
Florida in 2006 and 2007 were reported within 12 months of
their diagnosis. Further, less than 5% of the AIDS cases were
reported after death. Florida law requires both laboratory and
provider reporting. HIV/AIDS surveillance staff are strategi-
cally located throughout the state to provide timely and
complete reporting for their local areas. State-level HIV/AIDS
surveillance staff in Tallahassee routinely generate validation
reports to ensure complete reporting of all required demog-
raphic variables and elimination of duplicate cases. Although
behavioral risk information is not always available at the initial
report, efforts are made by staff in the field and at the state
level to identify sources of transmission when available.
HIV Incidence Estimates
HIV incidence refers to those with recently acquired
HIV infection, that is, on average, within 156 days of sero-
conversion.1The estimated numbers of recent HIV infections
in 2006 were determined by methods previously described
(incidence estimates for earlier or later years were not avail-
able).1Briefly, the number of recent HIV infections in the US
population was estimated from a sample composed of all
persons who were diagnosed with HIV in 2006 and classified
as recently infected using the BED HIV-1 capture enzyme
immunoassay. Information on HIV cases diagnosed in 2006
were included in the estimation calculations, adjusted
for reporting delays and redistribution of risk.17A sampling
weight was assigned to each person in the sample. The weight
was the inverse of the estimated probability that a case with
similar characteristics had a positive HIV test and was deter-
mined to have a recent infection by the serologic testing
algorithm for recent HIV seroconversion.18Newly diagnosed
cases in Florida were stratified by sex, race/ethnicity, age
group, and transmission category depending on the number of
cases per stratum and the CDC minimum requirements for
estimating HIV incidence. State-wide estimates were rounded
to the nearest 10 infections.
Although HIV incidence estimates were produced for
adults and adolescents aged $13 years, we limited the age
group to those aged $18 years to conform to our MSM defini-
tion. Examination of the Florida data indicated that the esti-
mated number of incident HIV infections among all those aged
13–17 yearswas negligible (,1.0% of total infections); thus, no
adjustments to the total estimates for MSM by race/ethnicity
were made for excluding this age group from the analysis.
Estimation of the Numbers of MSM
The denominators of each of the 3 HIV indicator rates
were the estimated numbers of MSM in Florida in 2006 or
2007, by race/ethnicity. These estimates were derived using
methods from our previous work,15where 2 statistical models
were used to estimate the total state-wide percentage of adult
maleswhowere MSM in the 17 states of the southern region of
2|www.jaids.comq 2010 Lippincott Williams & Wilkins
Lieb et al
J Acquir Immune Defic Syndr?Volume 00, Number 0, Month, 2010

Page 3

the United States in 2007, and the findings were averaged,
resulting in a Florida percentage MSM estimate of 7.5%. This
percentage MSM estimate was multiplied by the mid-year
2007 adult male population estimate19to obtain the estimated
totalnumberofMSMinthe statein2007.ThisnumberofMSM
was then partitioned by race/ethnicity using a third model.
Briefly, the first estimation model relied on national
estimates of the percentage of US males who were MSM in
rural, suburban, and urban areas, according to Laumann et al,20
and state-specific census data by corresponding geographic
area.21The second model relied on a national estimate of the
overall percentage of males who are MSM (ie, 6.0%) from the
National Survey of Family Growth,22which was multiplied by
an ‘‘MSM Index.’’ The MSM Index we constructed equaled
the ratio of the proportion of US same-sex unmarried male
partner households in a given state to the proportion of all US
households in the state.23By definition, the MSM Index for the
United States was 1.0. The third model was based on algebraic
conversions of national estimated percentages of males who
were MSM that were found in the National Survey of Family
Growth for whites (6.5%), blacks (5.0%), and Hispanics
(6.2%). The estimated percentages MSM for Florida were
determined to be 7.9% for whites, 6.1% for blacks, and 7.6%
for Hispanics. These percentages were multiplied by the mid-
year 2007 adult male population estimates, by race/ethnicity,19
to produce the racial/ethnic-specific MSM population esti-
mates. In the present study, we applied the same principals and
procedures to obtain the state-wide MSM estimates for 2006.
Assumptions and limitations of the methods for the 3 models
were thoroughly discussed in our previous report.15
Computation of Rates
The numbers of MSM living with HIV, deaths among
MSM with HIV, and estimated incident HIV infections among
MSM were divided by the estimated numbers of MSM to
produce the estimated indicator rates, by race/ethnicity.
Statistical significance of the rate ratios (RRs) was determined
by a 2-tailed test of difference from 1.0. For comparison with
MSM, we estimated the number of males who are not MSM in
Florida in 2006 (ie, those with an injection drug use, hetero-
sexual contact, or blood-related risk) and computed estimated
HIV incidence rates among them. We subtracted the estimated
numbers of MSM from the total adult male population, by
race/ethnicity, to obtain the denominators of the non-MSM
male HIVincidence rates. Numerators were similarly obtained
through subtraction of the MSM incidence numbers from the
total adult male incidence estimates.
Survival Analysis
We evaluated the median time from an AIDS diagnosis
to death for MSM and for males who are not MSM, by
race/ethnicity, for the 2 years combined (2006 and 2007).
Evaluation of median time from an HIV diagnosis to death was
not possible due to insufficient data on time of HIV diagnosis
for all cases.
Sensitivity Analysis
We conducted a sensitivity analysis to test the robustness
of the indicator rate estimates. In the original analysis, we
utilized as denominators MSM population estimates in Florida
by race/ethnicity from our previous work.15The white per-
centage MSM estimatewas approximately 30% and 4% higher
than that among black and Hispanic MSM, respectively. We
examined the possibility that minority MSM were misidenti-
fied as heterosexuals to a greater extent than white MSM,
consistent with a number of other reports.24–28
In the sensitivity analysis, we considered the degree to
which the observed racial/ethnic disparities in the original
analysis of the indicator rates were a function of underestimat-
ing the percentage and number of MSM among minorities.
Thus, we assumed that a history of male–male sexual behavior
was as common among black and Hispanic males as among
white males. Accordingly, we set the estimated percentage
MSM among blacks and Hispanics within Florida as equal to
the higher white percentage MSM (7.9%). We then recom-
puted the estimated indicator rates for MSM by race/ethnicity
under this assumption, although holding constant the numbers
of MSM who were living with HIV, deaths among MSM with
HIV, and HIV incidence estimates (ie, the numerators of the
respective rates). We evaluated the extent to which racial/
ethnic disparities persisted in the sensitivity analysis as
measured by the estimated RRs and associated P values.
Racial/Ethnic Categories
Computation of rates for the 3 HIV indicators by
race/ethnicity was limited to MSM in the 3 major demographic
categories, that is, whites, blacks, and Hispanics. American
Indians/Alaska Natives, Asians/other Pacific Islanders, and
those of unknown or multiple race/ethnicity accounted for too
few MSM HIV cases, deaths, and incident HIV infections for
reliable statistical analysis.
Data Analysis
The P values and 95% confidence intervals of the RRs
were determined using R software [R Core Development Team
(computer software) Version 2.5.1. Vienna: R Foundation for
Statistical Computing; 2004]. Tests of significance comparing
the differences in 2 RRs were conducted using a method
from Kanji.29The Wilcoxon test was used to determine the
statistical significance of differences in median times from
AIDS diagnosis to death.30
RESULTS
The estimated total number of white, black, and
Hispanic MSM in Florida increased by 1.4% from 2006
(501,412) to 2007 (508,448) (Table 1), largely reflecting
a year’s growth in the overall adult male population in the state
because the percentage of adult males who were estimated to
be MSM was assumed to remain essentially unchanged across
the 2 years. Meanwhile, the total number of prevalent MSM
HIV cases increased by 7.0%, from 36,878 to 39,447. Nearly
half the prevalent cases were among white MSM in both
years. Estimated HIV prevalence rates increased from 2006 to
2007 by 5.5% overall, with 5.7%, 4.0%, and 4.8% increases,
respectively, among white, black, and Hispanic MSM. The
estimated prevalence rates among black and Hispanic MSM,
respectively, were 3.7 and 1.7 times that of white MSM in
q 2010 Lippincott Williams & Wilkins
www.jaids.com|3
J Acquir Immune Defic Syndr?Volume 00, Number 0, Month, 2010 HIV Incidence, Prevalence, and Mortality Rates Among MSM

Page 4

2006, and 3.6 and 1.7 times that of white MSM in 2007
(all P , 0.001). The black-to-Hispanic HIV prevalence RR in
both years was 2.2 (P , 0.001).
Black/white racial/ethnic disparities in estimated death
rates among MSM HIV cases were more pronounced than the
disparities in the corresponding prevalent HIV case rates in
both 2006 and 2007. The black-to-white MSM HIV death
RR in 2006 (5.4) (Table 2) was significantly greater than the
black-to-white MSM HIV prevalence RR (3.7) (P , 0.001).
The corresponding RRs also differed in 2007 (4.9 and
3.6, respectively) (P , 0.001). Death rates among MSM HIV
cases decreased in 2007 among black MSM by 8.7% and
among Hispanic MSM by 13.7%, but remained level among
white MSM.
The survival analysis indicated racial/ethnic disparities
in the median time from a diagnosis of AIDS to death in both
years. For deaths that occurred in 2006 and 2007 (combined
data), this length of time was 79 months for white MSM,
56 months for black MSM, and 62 months for Hispanic
MSM (white MSM vs. black MSM, P , 0.001; white MSM
vs. Hispanic MSM, P , 0.05; Hispanic MSM vs. black
MSM, P not significant). By contrast, for males who were not
MSM, the median time from AIDS to death was 51 months for
whites, 43 months for blacks, and 33.5 months for Hispanics
(all comparisons, P not significant). All 3 racial/ethnic-specific
comparisons of MSM vs. males who were not MSM were
significant at P , 0.01.
In 2006, the total HIV incidence estimate for the United
States was 56,300, of which 30,800 (54.7%) infections were
among MSM.1Florida’s incidence estimate was 5550, of
which 3350 (60.4%) infections occurred among MSM in all
racial/ethnic groups. HIV incidence rates per 100,000 MSM
among black MSM (2154.2) and Hispanic MSM (767.4) were
higher than the rate among white MSM (392.6), whereas
the black MSM rate was also higher than the Hispanic MSM
rate (P , 0.001 for all comparisons) (Table 3). The black-to-
white MSM incidence RR (5.5) was similar to the cor-
responding MSMHIV death RRin 2006 (5.4) but significantly
greater than the corresponding MSM HIV prevalence RR (3.7)
(P , 0.01). Estimated HIV incidence numbers and rates
among males who are not MSM were relatively very low.
Dividing the MSM HIVincidence rates by the non-MSM male
incidence rates thus resulted in extremely high RRs (130.9 for
whites, 45.4 for blacks, 94.7 for Hispanics, and 65.3 overall)
(all P , 0.001).
The sensitivity analysis suggested the HIV rates
according to each of the indicators were fairly robust to error
associated with misclassification of minority MSM as non-
MSM males (Table 4). For all 3 measures, rates remained
significantly elevated among black and Hispanic MSM
compared with those among white MSM (all P , 0.001),
although the rates and RRs were lower than in the original
analysis. As with the original analysis, each indicator rate in
TABLE 1. Estimated Number of MSM and Population-Based HIV Prevalence Rates Among MSM ($18 Yrs.), by Race/Ethnicity,
Florida, 2006–2007
Estimated MSMMSM HIV Prevalence*
YearRace/Ethnicity Number†% of Total Cases% of Total RateRR‡ 95% CI
2006White
Black
Hispanic
Total§
White
Black
Hispanic
Total§
346,383
53,385
101,644
501,412
348,043
54,717
105,688
508,448
69
11
20
100
68
11
21
100
17,948
10,160
8770
36,878
19,059
10,829
9559
39,447
49
28
24
100
48
27
24
100
5181.5
19,031.6
8628.2
7354.8
5476.0
19,790.9
9044.5
7758.3
1.00
3.67
1.67
—
1.00
3.61
1.65
—
3.59 to 3.76
1.62 to 1.71
—
—
3.54 to 3.69
1.61 to 1.69
2007
Rates are per 100,000 MSM.
*HIV prevalence numbers represent reported HIV or AIDS cases that were alive through the end of 2006 or 2007.
†Estimated numbers of MSM are based on Lieb et al15and are equal, respectively, to the Florida 2006 and 2007 mid-year racial/ethnic-specific male populations aged $18 yrs.
multiplied by the following percentages of males who are MSM: 7.9% for whites, 6.1% for blacks, 7.6% for Hispanics, and 7.5% overall (see Text).
‡All RRs are significant at P , 0.001.
§Totals include white, black, and Hispanic MSM only.
MSM, men who have sex with men (includes MSM who have used injection drugs); RR, rate ratio; CI, confidence interval.
TABLE 2. Estimated Population-Based Death Rates Per
100,000 MSM Among MSM With HIV (.18 Yrs.), by Race/
Ethnicity, Florida, 2006–2007
Deaths Among MSM With HIV*
Year Race/EthnicityNumber % of Total RateRR†95% CI
2006White
Black
Hispanic
Total‡
White
Black
Hispanic
Total‡
437
361
204
1002
437
338
183
958
44
36
20
126.2
676.2
200.7
199.8
125.6
617.7
173.2
188.4
1.0
5.4
1.6
—
1.0
4.9
1.4
—
—
4.7 to 6.2
1.3 to 1.9
—
—
4.3 to 5.7
1.2 to 1.6
—
100
46
35
19
100
2007
Rates are per 100,000 MSM.
Denominators of the death rates (not shown) are the same as the denominators
(estimated numbers of MSM) shown in Table 1.
*Deaths may be due to any cause.
†All RRs are significant at P , 0.001.
‡Totals include white, black, and Hispanic MSM only.
MSM, men who have sex with men (includes MSM who have used injection drugs);
RR, rate ratio; CI, confidence interval.
4|www.jaids.comq 2010 Lippincott Williams & Wilkins
Lieb et al
J Acquir Immune Defic Syndr?Volume 00, Number 0, Month, 2010

Page 5

the sensitivity analysis was also higher among black MSM
than among Hispanic MSM (P , 0.001).
DISCUSSION
The absolute numbers of incident HIV infections and
deaths among MSM with HIV in Florida relate one part of the
epidemic narrative, as they drive MSM HIV prevalence.
Further perspective is gained by the conversion of these
numbers to population-based rates, enabling direct compar-
isons of the impact of HIV on individual groups of MSM.
White MSM in our study account for the greatest number of
new HIV infections, prevalent HIV cases, and deaths among
HIV cases, mainly due to their larger population size, butblack
and Hispanic MSM experience significantly greater impact,
according to each measure. Despite evidence that suggests
black MSM have no riskier behavior than white MSM,26,28
HIV has gained a greater foothold in the black MSM
population, with an HIV prevalence rate equivalent to roughly
19% (or 1 in 5) in both 2006 and 2007, which was nearly 4
times that of white MSM in those years.
Increases in HIV prevalence rates among all racial/eth-
nic groups of MSM can be expected to continue as long as the
annual number of deaths is lower than the annual number of
incident HIV infections. This assumes the percentage growth
in numbers of prevalent HIV cases continues to outpace the
percentage growth in MSM populations. Enhanced reporting
in Florida was implemented in November 2006 (ie, viral loads
and CD4 counts became reportable), resulting in some
increased HIV case ascertainment. A shift from paper to
TABLE 3. Estimated Population-Based HIV Incidence Rates Among MSM and Males Who are not MSM ($18 Yrs.), by Race/
Ethnicity, Florida, 2006
Race/Ethnicity
Estimated MSMEstimated MSM HIV Incidence
Number*% of TotalNumber% of TotalRateRR† 95% CI
White
Black
Hispanic
Total‡
346,383
53,385
101,644
501,412
69
11
20
100
1360
1150
780
3290
41
35
24
392.6
2154.2
767.4
656.1
1.0
5.5
2.0
—
—
5.1 to 5.9
1.8 to 2.1
— 100
Race/ethnicity
Estimated non-MSM males Estimated non-MSM male HIV incidence
Number§% of total Number% of total RateRR†(95% CI)
White
Black
Hispanic
Total‡
4,021,897
821,838
1,242,218
6,085,953
66
14
20
100
120
390
100
610
20
64
16
3.0
47.5
8.1
10.0
1.0
15.9
2.7
—
—
13.0 to 20.0
2.1 to 3.6
—100
Rates are per 100,000 MSM or per 100,000 non-MSM males.
*Estimated numbers of MSM are based on Lieb et al., 2009,15and are equal to the Florida 2006 midyear racial/ethnic-specific male populations aged $18 yrs. multiplied by the
following percentages of males who are MSM: 7.9% for whites, 6.1% for blacks, 7.6% for Hispanics, and 7.5% overall (see text).
†All RRs are significant at P , 0.001.
‡Totals include white, black, and Hispanic MSM only.
§Numbers of non-MSM males were obtained by subtracting the estimated numbers of MSM from the population of all males ($18 yrs.) in each racial/ethnic group.
MSM, men who have sex with men (includes MSM who have used injection drugs); RR, rate ratio; CI, confidence interval.
TABLE 4. Sensitivity Analysis*: Adjusted Estimated HIV Prevalence, Death, and Incidence Rates Among MSM ($18 Yrs.), by Race/
Ethnicity, Florida, 2006
Race/Ethnicity
Estimated MSMEstimated MSM
HIV PrevalenceDeaths Among MSM with HIV HIV Incidence
RateRR†95% CIRate RR† 95% CIRate RR†95% CI
White
Black
Hispanic
Total‡
5181.5
14,639.6
8230.0
7060.1
1.00
2.78
1.58
—
—126.2
520.2
191.4
191.8
1.00
4.12
1.52
—
—392.6
1657.0
732.0
629.9
1.00
4.22
1.86
—
—
2.76 to 2.89
1.55 to 1.63
—
3.59 to 4.74
1.29 to 1.79
—
3.90 to 4.56
1.71 to 2.04
—
Rates are per 100,000 MSM.
*In the sensitivity analysis, the estimated number of MSM in Florida in 2006 (not shown) assumes the percentage of adult males who are MSM among blacks and Hispanics is the
same as that among whites (7.9%) (see text).
†All RRs are significant at P , 0.001.
‡Totals include white, black, and Hispanic MSM only.
MSM, men who have sex with men (includes MSM who have used injection drugs); RR, rate ratio; CI, confidence interval.
q 2010 Lippincott Williams & Wilkins
www.jaids.com|5
J Acquir Immune Defic Syndr?Volume 00, Number 0, Month, 2010HIV Incidence, Prevalence, and Mortality Rates Among MSM

Page 6

electronic laboratory reporting improved completeness and
timeliness in the reporting both of HIV and AIDS cases in
2007. These factors also contributed to an increase in the
observed HIV prevalence from 2006 to 2007. Meanwhile, no
reporting changes influenced the number of deaths among
MSM with HIV during the 2 years, as there was ongoing
matching of HIV cases with Florida vital statistics and the
Social Security Death Index to ascertain deaths. The level of
death rates among white MSM with HIV from 2006 to 2007,
compared with the decreases in death rates among black and
Hispanic MSM with HIV, warrant close monitoring for trend.
Black MSM with HIV had approximately a 5-fold
greater death rate than their white counterparts in 2006 and
2007, perhaps reflecting greater rates of undiagnosed or late-
diagnosed HIV infection among black MSM, as has been
previouslyreported.28,31,32Overall, blacks seem to be relatively
less likely to have access to quality HIV care and treatment
than whites.33–35The 5-fold greater estimated HIV incidence
rate for black MSM and 2-fold greater rate for Hispanic MSM,
compared with white MSM, could reflect greater pre-existing
HIV prevalence in the overall minority communities.
Racial/ethnic minority MSM might perceive or experience
increased stigma, contributing to delayed screening and
treatment,36,37and affecting racial/ethnic disparities both in
incidence and death rates.
Late diagnosis of HIV and AIDS, which has been
documented among minority MSM,28,31,32could account for
the greater median survival time from AIDS diagnosis to death
among white MSM, compared with black and Hispanic MSM.
However, compared with males who were not MSM, MSM
seemed to have a survival advantage for each racial/ethnic
group, for reasons requiring further research.
MSM had extremely high estimated HIV incidence
rates, compared with males who are not MSM, with the rate
among black MSM exceeding 2% in 2006 (2154.2 per
100,000 MSM). However, the black-to-white HIV incidence
RR among males who are not MSM (15.9) was much greater
than the corresponding black-to-white RR among MSM (5.5)
(Table 3). Low HIV incidence among white males who are not
MSM could be associated with the relatively small proportion
of white men diagnosed with HIV who are classified as
high-risk heterosexuals or IDUs. An understanding of the
impact of HIV on non-MSM males would be advanced by
estimates of population-based rates of each of the 3 measures
among these 2 important behavioral risk groups. Estimates
of IDU populations and HIV seroprevalence rates among
IDUs have been reported for 96 large metropolitan areas of the
United States.38–40However, reliable population estimates of
high-risk heterosexuals and IDUs by race/ethnicity remain
to be developed at the state level for computation of HIV
indicator rates.
Consideration of several underlying factors could help
clarify the observed disparities. Stigma and denial, including
fear of learning one’s HIV status or disclosing one’s HIV-
positive status, are an impediment to prevention.36,37,41,42
Discrimination and homophobia can lead to fear of disclosure
of being a gay man/MSM.43HIV complacency and treatment
optimism can result in reduction or loss of fear of
infection.44,45Disparities in the HIV indicator rates might be
further explained by racial/ethnic tendencies in social mixing
and sexual partnering, which were examined in 1 recent San
Francisco study of racial mixing and HIV risk among MSM.46
A survey determined the observed and expected number and
percentage of partnerships of the same race/ethnicity, finding
that black MSM were 3 times more likely to have partners who
were also black, compared with what was expected. Black
MSM seemed to be largely limited by peers to sexual contacts
within their own race/ethnicity, which may or may not align
with the personal preferences of black MSM. As long as this
social tendency exists, HIV will pass more readily and
repeatedly within the black MSM community. To the extent
that Florida MSM have social/sexual mixing tendencies
similar to those in San Francisco, a high degree of inter-
connectedness could have led to a more rapid HIV trans-
mission and a higher sustained HIV prevalence among black
MSM than among white or Hispanic MSM.
Each of the 3 measures we considered has public health
implications. HIV incidence estimates among MSM can help
lead to more effectiveprimaryHIV preventionefforts, whereas
prevalent MSM HIV cases represent an opportunity for
implementing targeted secondary HIV prevention efforts, that
is, reduction of transmission from those known to be infected.
Deaths among HIV cases indicate a need for earlier diagnosis
through increased and routine testing, and improved linkage
and access to quality care and treatment. Evaluation of
progress in meeting HIV prevention goals and objectives is
possible by monitoring these measures among MSM and
computing the estimated population-based rates to which
they give rise.
Our findings have a number of limitations. Numerator
issues include the accuracy of imputing HIV risk for cases,
deaths, and infections among men with no identified risk
behavior. The methodology for developing HIV incidence
estimates has thus far been applied to a single year only,
although national estimates for 2006 were corroborated with
modeled back calculation.1Further limitations of the HIV
incidence estimates include the influence of variability due to
missing data, the percentage of recent BED cases, and the
percentage of all infections with a concurrent diagnosis of
AIDS.1The HIV incidence estimates include those who are
aware of their HIV infection and those who are unaware,
whereas the HIV prevalence estimates include only those who
havebeen diagnosed. True HIV prevalencewould include both
diagnosed and undiagnosed MSM living with HIVand would
thus be higher than presented. An estimated 22% of HIV-
infected MSM in the United States do not know their
serostatus,3although this estimate has not been stratified by
race/ethnicity. Increasingly, in the era of improved antire-
troviral therapies, deaths among HIV cases are associated with
underlying causes other than HIV/AIDS,47–49but cause of
death data were not examined in our study.
Denominator issues, which were extensively addressed
in our previous study,15begin with the problem of eliciting
a history of male–male sex contact in behavioral surveys, and
2 of these surveys provided input data for our 3 denominator
estimation models.20,22This is perhaps the greatest source of
bias in estimating MSM populations by race/ethnicity. A
number of studies have suggested that minority men are less
6|www.jaids.comq 2010 Lippincott Williams & Wilkins
Lieb et al
J Acquir Immune Defic Syndr?Volume 00, Number 0, Month, 2010

Page 7

likely to disclose male–male sex contact than white men.24–28
Our sensitivity analysis took this possibility into account by
setting the percentage of black and Hispanic men who were
MSM equal to that of white MSM. Significant racial/ethnic
disparities in the 3 indicators of interest persisted in the
estimates, although the absolute rates and RRs decreased.
The intensity of the epidemic among MSM is not
uniform across the state. Routine HIV surveillance data
suggest considerable variability by locality.5The estimated
indicator rates could differ by urban/suburban/rural geo-
graphic areas, undetectable by our methods. There could be
issueswith the broad inclusive definition of MSM that we used
for the denominators of the rates. It captures experimenters
and those without ongoing male–male sexual behavior. It does
not specify the type of sexual activity, for example, oral or
anal. The result could be overestimates of those with recent
male–male sex contact of a specific type. However, our MSM
definition is aligned with the one used by CDC for national
HIV/AIDS surveillance.16Overestimates of numerator and
denominator data are not cancelled out when converted to HIV
indicator rates but could be somewhat offsetting. Further
research is needed to validate the assumptions we have made
and to determine the extent to which our findings might apply
to other states.
Despite limitations, the findings we present indicate that
resources are urgently needed to scale up a comprehensive
culturally specific set of primary and secondary HIV preven-
tion interventions for Florida MSM. Structural interventions
should be designed and implemented,50which attempt to
influence social, political, or economic environments that
affect a community’s overall behaviors and beliefs simulta-
neously. Effective social marketing campaigns are needed.
Grassroots advocacy and community mobilization should
be promoted to complement local health department HIV
prevention initiatives.
Our estimates of HIV incidence, HIV prevalence, and
death rates among racial/ethnic MSM populations could
provide important insight into the epidemic, guiding research-
ers, planners, and policymakers in addressing the above
imperatives. Estimates based on empirical research or further
independent modeling of the denominators of the rates could
help refine the current rates of the measures, improve
program/policy guidance, and better inform resource alloca-
tion. Many other states could readily apply our methods to
compute the estimated HIV rates among MSM, deriving the
denominators by applying our previously reported methodol-
ogy.15To the extent that the rates we present reflect the actual
situation in Florida, there will be considerable public health
utility to the estimates.
ACKNOWLEDGMENTS
The authors are grateful for the efforts of Florida’s
numerous local HIV/AIDS surveillance staff for gathering
and reporting information on cases. Lorene Maddox, MPH,
and Julia Fitz, MPH, are acknowledged forproviding essential
ad hoc HIV/AIDS surveillance data. For their helpful review of
the article, we thank Mary Jo Trepka, MD, MSPH, Billy
Robinson, PhD, and Dano R. Beck, MSW.
REFERENCES
1. Hall HI, Song R, Rhodes P, et al. Estimation of HIV incidence—United
States. JAMA. 2008;300:520–529.
2. Prejean J, Song R, An Q, et al. Subpopulation estimates from the HIV
incidence surveillance system—United States. MMWR Morb Mortal Wkly
Rep. 2008;57:985–989.
3. Campsmith ML, Rhodes P, Hall HI, et al. HIV prevalence estimates—
United States, 2006. JAMA. 2009;301:27–29.
4. CDC. HIV/AIDS Surveillance Report, 2007. Atlanta: Centers for Disease
Control and Prevention; 2009. Vol 19.
5. Bureau of HIV/AIDS. Florida Monthly HIV/AIDS Surveillance Reports.
Tallahassee, FL: Florida Department of Health. Available at: http://
www.floridaaids.org. Accessed October 28, 2009.
6. Friedman, SR, Sotheran JL, Abdul-Quader, A, et al. The AIDS epidemic
among blacks and Hispanics. Milbank Q. 1987;65:455–499.
7. Holmberg SD. The estimated prevalence and incidence of HIV in 96 large
US metropolitan areas. Am J Public Health. 1996;86:642–654.
8. Catania JA, Osmond D, Stall RD, et al. The continuing HIV epidemic
among menwho have sex with men.Am J Public Health.2001;91:207–214.
9. MacKellar D, Valleroy L, Karon J, et al. The young men’s survey: methods
for estimating HIV seroprevalence and risk factors among young men
who have sex with men. Public Health Rep. 1996;111(Suppl 1):138–144.
10. ValleroyLA,DuncanA,MacKellarMA,etal.HIVprevalenceandassociated
risks in young men who have sex with men. JAMA. 2000;284:198–204.
11. Centers for Disease Control and Prevention. HIV prevalence, un-
recognized infection, and HIV testing among men who have sex with
men—five U.S. Cities, June 2004–April 2005. MMWR Morb Mortal Wkly
Rep. 2005;54:597–601.
12. Holtgrave DR. Estimation of annual HIV transmission rates in the United
States, 1978–2000. J Acquir Immune Defic Syndr. 2004;35:89–92.
13. Lieb S, Arons P, Thompson DR, et al.Men who have sex with men: racial/
ethnicdisparitiesinestimatedHIV/AIDSprevalenceatthestateandcounty
level, Florida. AIDS Behav. 2009;13:716–723. Epub June 10, 2008.
14. Lieb S, Trepka MJ, Thompson DR, et al. Men who have sex with men:
estimated population sizes and mortality rates, by race/ethnicity, Miami-
Dade County, Florida. J Acquir Immune Defic Syndr. 2007;46:485–490.
15. Lieb S, Thompson DR, Misra S, et al. Estimating populations of men who
have sex with men in the southern United States. J Urban Health. 2009;
86:887–901.
16. Centers for Disease Control and Prevention. Adult HIV/AIDS Confidential
Case Report. Form CDC 50.42A, rev. 01/ 2003:1. Atlanta: Centers for
Disease Control and Prevention; 2003.
17. Green TA. Using surveillance data to monitor trends in the AIDS
epidemic. Stat Med. 1998;17:143–154.
18. Janssen RS, Satten GA, Stramer SL, et al. New testing strategy to detect
early HIV-1 infection for use in incidence estimates and for clinical and
prevention purposes. JAMA. 1998;280:42–48.
19. US Census Bureau. Midyear population estimates, April 1, 2000 to July 1,
2008. Available at http://www.census.gov/popest/datasets.html. Accessed
October 10, 2009.
20. Laumann, EO, Gagnon JH, Michael RT, et al. In: The Social Organization
of Sexuality: Sexual Practices in the United States. Chicago, IL:
University of Chicago Press; 1994. Chapter 8.
21. U.S. Census Bureau, 2000 Census, Summary File 1 (SF 1), Table P.2.
Urban and rural. Available at: http://factfinder.census.gov/. Accessed
April 27, 2009.
22. National Center for Health Statistics. Sexual behavior and selected health
measures: men and women 15–44 years of age, United States, 2002.
Advance Data 362, 2005. Available at: http://www.cdc.gov/nchs/data/ad/
ad362.pdf. Accessed October 3, 2009.
23. US Census Bureau. American Community Survey, 2005–2007. Data
averaged for the 3 years, 2005–2007. Available at: http://factfinder.
census.gov/. Accessed January 3, 2009.
24. Nyblade LC. Measuring HIV stigma: existing knowledge and gaps.
Psychol Health Med. 2006;11:335–345.
25. Pathela P, Hajat A, Schillinger J, et al. Discordance between sexual
behavior and self-reported sexual identity: a population-based survey of
New York City men. Ann Intern Med. 2006;145:416–425.
26. Mays V, Cochran S, Zamudio A. HIV prevention research: are we meeting
the needs of African American men who have sex with men? J Black
Psychol. 2004;30:78–105.
q 2010 Lippincott Williams & Wilkins
www.jaids.com|7
J Acquir Immune Defic Syndr?Volume 00, Number 0, Month, 2010HIV Incidence, Prevalence, and Mortality Rates Among MSM

Page 8

27. Kennamer JD, Honnold J, Bradford J, et al. Differences in disclosure of
sexuality among African American and white gay/bisexual men: implica-
tions for HIV/AIDS prevention. AIDS Educ Prev. 2000;12:519–531.
28. Centers for Disease Control and Prevention. HIV/STD risks inyoung men
who have sex with men who do not disclose their sexual orientation—six
U.S. cities, 1994–2000. MMWR Morb Mortal Wkly Rep. 2003;52:81–85.
29. Kanji GK. 100 Statistical Tests. Newberry Park, CA: Sage Publications;
2001:134.
30. Hollander M, Wolfe DA. Nonparametric Statistical Methods. New York,
NY: John Wiley & Sons; 1973:27–33, 68–75.
31. MacKellar DA, Valleroy LA, Secura GM, et al. Unrecognized HIV
infection, risk behaviors, and perceptions of risk among young men who
have sex with men: opportunities for advancing HIV prevention in the
third decade of HIV/AIDS. J Acquir Immune Defic Syndr. 2005;38:
603–614.
32. McGinnis KA, Fine MJ, Sharma RK, et al. Understanding social
disparities in HIVusing data from the Veterans Aging Cohort 3-Site Study
and VA Administrative Data. Am J Public Health. 2003;93:1728–1733.
33. Jain S, Schwarz S, Katz M, et al. Elevated risk of death for African
Americans with AIDS, San Francisco, 1996–2002. J Health Care Poor
Underserved. 2006;17:493–503.
34. Wong MD, Cunningham WE, Shapiro MF. Disparities in HIV treatment
and physician attitudes about delaying protease inhibitors for nonadherent
patients. J Gen Intern Med. 2004;19:366–374.
35. King WD, Wong MD,Shapiro MF.Does racial concordance between HIV-
positive patients and their physicians affect the time to receipt of protease
inhibitors. J Gen Intern Med. 2004;19:1146–1153.
36. Lichtenstein B. Stigma as a barrier to treatment of sexually transmitted
infection in the American deep south: issues of race, gender, and poverty.
Soc Sci Med. 2003;57:2435–2445.
37. Chesney MA, Smith AW. Critical delays in HIV testing and care. Am
Behav Sci. 1999;42:1162–1174.
38. Brady JE, Friedman SR, Cooper HL, et al. Estimating the prevalence of
injection drug users in the U.S. and in large U.S. metropolitan areas from
1992 to 2002. J Urban Health. 2008;85:323–351.
39. Friedman SR, Lieb S, Tempalski B, et al. HIVamong injection drug users
in large US metropolitan areas, 1998. J Urban Health. 2005;82:434–445.
40. Tempalski B, Lieb S, Cleland CM, et al. HIV prevalence rates among
injection drug users in 96 large US metropolitan areas, 1992–2002.
J Urban Health. 2009;86:132–154.
41. Bogart LM, Thorburn S. Are HIV/AIDS conspiracy beliefs a barrier to
HIV prevention among African Americans? J Acquir Immune Defic
Syndr. 2005;38:213–218.
42. Whetten K, Reif S, Whetten R, et al. Trauma, mental health, distrust,
and stigma among HIV-positive persons: implications for effective care.
Psychosomatic Med. 2008;70:531–538.
43. Shoptsaw S, Weiss RE, Munjas B, et al. Homonegativity, substance abuse,
sexual risk behaviors, and HIV status in poor and ethnic men who have
sex with men in Los Angeles. J Urban Health. 2009;86(Suppl 1):77–92.
44. Chan DJ, Begley K, Smith DE. HIV-1 transmission amongst men who
have sex with men: a probabilistic model incorporating antiretroviral
treatment optimism-skepticism, sexual beliefs and sexual behavior. Curr
HIV Res. 2009;7:231–236.
45. Valdiserri RO. Mapping the roots of HIV/AIDS complacency: implica-
tions for program and policy development. AIDS Educ Behav. 2004;16:
426–439.
46. Raymond HF, McFarland W. Racial mixing and HIV risk among men who
have sex with men. AIDS Behav. 2009;13:630–637.
47. Stein JH. ‘‘Cardiovascular risks of antiretroviral therapy.’’ New Engl J
Med. 2007;356:1773–1775.
48. Bedimo RJ, McGinnis KA, Dunlap M, et al. Incidence of non-AIDS-
defining malignancies in HIV-infected versus noninfected patients in the
HAART era: impact of immunosuppression. J Acquir Immune Defic
Syndr. 2009;52:203–208.
49. De Wit S, Sabin C, Weber R, et al. Incidence and risk factors for new-
onset diabetes in HIV-infected patients: the data collection on adverse
events of anti-HIV drugs (D:A:D) study. Diabetes Care. 2008;31:
1224–1229.
50. Gupta GR, Parkhurst JO, Ogden JA, et al. Structural approaches to HIV
prevention. Lancet. Aug 5, 2008. E-pub ahead of print.
8|www.jaids.comq 2010 Lippincott Williams & Wilkins
Lieb et al
J Acquir Immune Defic Syndr?Volume 00, Number 0, Month, 2010