Christopher H. Johnson

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PROBLEM As of December 31, 2009, an estimated 864,748 persons were living with human immunodeficiency virus (HIV) infection in the 50 U.S. states, the District of Columbia, and six U.S.-dependent areas. Whereas HIV surveillance programs in the United States collect information about persons with a diagnosis of HIV infection, supplemental surveillance(More)
BACKGROUND Injection drug use provides an efficient mechanism for transmitting bloodborne viruses, including human immunodeficiency virus (HIV) and hepatitis C virus (HCV). Effective targeting of resources for prevention of HIV and HCV infection among persons who inject drugs (PWID) is based on knowledge of the population size and disparity in disease(More)
BACKGROUND CDC has not previously calculated disease rates for men who have sex with men (MSM) because there is no single comprehensive source of data on population size. To inform prevention planning, CDC developed a national population size estimate for MSM to calculate disease metrics for HIV and syphilis. METHODS We conducted a systematic literature(More)
Epidemiologic and clinical changes in the HIV epidemic over time have presented a challenge to public health surveillance to monitor behavioral and clinical factors that affect disease progression and HIV transmission. The Medical Monitoring Project (MMP) is a supplemental surveillance project designed to provide representative, population-based data on(More)
Monitoring delayed entry to HIV medical care is needed because it signifies that opportunities to prevent HIV transmission and mitigate disease progression have been missed. A central question for population-level monitoring is whether to consider a person linked to care after receipt of one CD4 or VL test. Using HIV surveillance data, we explored two(More)
OBJECTIVE To describe the prevalence and association of sexual risk behaviours and viral suppression among HIV-infected adults in the United States. DESIGN Cross-sectional analysis of weighted data from a probability sample of HIV-infected adults receiving outpatient medical care. The facility and patient response rates were 76 and 51%, respectively. (More)
INTRODUCTION Routine prenatal human immunodeficiency virus (HIV) screening provides a critical opportunity to diagnose HIV infection, begin chronic care, and prevent mother-to-child transmission. However, little is known about the prevalence of prenatal HIV testing in the US-Mexico border region. We explored the correlation between prenatal HIV testing and(More)
INTRODUCTION High birth and immigration rates in the US-Mexico border region have led to large population increases in recent decades. Two national, 10 state, and more than 100 local government entities deliver reproductive health services to the region's 14 million residents. Limited standardized information about health risks in this population hampers(More)
BACKGROUND This study estimated the proportions and numbers of heterosexuals in the United States (U.S.) to calculate rates of heterosexually acquired human immunodeficiency virus (HIV) infection. Quantifying the burden of disease can inform effective prevention planning and resource allocation. METHODS Heterosexuals were defined as males and females who(More)