Characterizing factors associated with HIV transmissions in Iowa

Undiagnosed people living with HIV/AIDS (PLWHA) make up 14% of PLWHA but contribute to 40% of transmissions. CDC is using a new model based on CD4 T-cells to estimate the proportion of people with undiagnosed HIV, but the model ignores migration. We evaluated the appropriateness of this model among diagnosed foreign-born Iowans. Many of whom may have acquired HIV outside of Iowa. Simulated analyses showed that misclassification of out-of-state transmissions as in-state overestimated the number of undiagnosed HIV by 13% when cases among foreign-born people comprised 30% of all diagnoses.

HIV diagnoses that occur at late stages of disease are more difficult to treat and allow for continued transmission. State-level factors may account for different proportions of late HIV diagnoses in the U.S., which were used to create a composite risk score. While the score was not associated with late HIV diagnoses, we learned three important components (i.e., Age group, Risk factors, and Socioeconomic status) accounted for a large proportion (~80%) of the variance.

People with late HIV diagnoses often have barriers at the individual level that can be influenced by geography. We explored the availability of health care providers, clinics, and other test sites near the residences of people with late versus early HIV diagnoses. There were no differences in the characteristics or frequency of these resources, but spatial mixed models suggest rurality may differentially influence HIV screening practices among providers at distances of 30- or 50-miles. Thus, future studies are needed to explore this and other associations further.