Two Independent Epidemics of HIV in Maryland

Abstract

Multiple HIV-1 subtypes exist in the Baltimore-Washington metropolitan area with a significant non-B-infected population in the Maryland suburbs of Washington, DC, suggesting 2 independent epidemics of HIV in Maryland. Population-based surveillance inclusive of groups at higher risk of non-B strains is essential to monitor the prevalence and variations of HIV subtypes in Maryland and the United States.

Large-Scale Analysis of the Prevalence and Geographic Distribution of HIV-1 Non-B Variants in the United States

“…Of interest, although 70.1% of the total sequences were obtained from males, the majority (55.5%) of non-subtype B infections were in females. The bias toward females harboring non-B infections presumably reflects predominantly heterosexual transmission of these variants and is consistent with results from another recent U.S. study (34). However, due to the design of our study, information on the route of transmission and patients' country of origin is not available.…”

“…Of the 798 non-B strains identified, the majority were subtype C (34.2%), followed by subtype A (18.5%), CRF02_AG (17.9%), and CRF01_AE (6.5%). These four forms represented more than 77% of all non-B strains, which is consistent with several other U.S. studies (32,34,48 HIV Sequence Database). Of interest, although 70.1% of the total sequences were obtained from males, the majority (55.5%) of non-subtype B infections were in females.…”

“…Seventeen states each had fewer than 100 sequences represented (385 sequences, 1.58% of the total), and nine of these states had no non-B sequences, as shown in Figure 2 and Table 3. The potential for large regional differences in the proportion of non-subtype B even within a state has been demonstrated (34). Third, the determination of subtype is based on analysis of resistance genotyping sequence information, which is ϳ15% of the complete HIV-1 genome.…”

“…Most studies have focused on specific populations, such as military personnel, immigrants, or blood donors (25)(26)(27)(28)(29)(30)(31). There is evidence of increasing non-B prevalence in the United States, and it may be higher than generally recognized (29,(32)(33)(34). Although data are limited, studies have shown that the prevalence of non-subtype B varies greatly depending on the population analyzed, ranging from 0.6% in a northern California clinic-based setting (35) to 95% in African-born immigrants in Minneapolis, MN (28,36), and New York City (27).…”

Short Communication: The Impact of Viral Suppression and Viral Breakthrough on Limited-Antigen Avidity Assay Results in Individuals with Clade B HIV Infection

“…13 Three groups of individuals were assessed: (1) 18 The difference between the OD-n values for individuals who were and were not virally suppressed was analyzed and evaluated. We analyzed the change in OD-n values in longitudinally paired samples, where individuals were suppressed at both time points (n = 120) or at only one time point (n = 22) (Fig.…”