RESUMO
BACKGROUND: We aim to identify optimal strategies for deploying pre-exposure prophylaxis among men who have sex with men (MSM) in the United States and Peru to maximize population-level effectiveness in an efficient manner. We use epidemic models to simulate the impact of targeting strategies. Most studies have focused on targeting either the general population or high-risk MSM. Alternative strategies, including serodiscordant couples, may better balance effectiveness and efficiency. METHODS: We use dynamic stochastic sexual network models based on exponential-family random graph modeling, parameterized from behavioral surveys of MSM in the United States and Peru. These models represent main partnerships and casual contacts separately, permitting modeling of interventions targeting men whose risk derives from combinations of relational types. We also model varying rates of uptake and adherence to pre-exposure prophylaxis (PrEP). We assess sensitivity of results to risk compensation through increases in condomless casual contacts and condomless sex in main partnerships. RESULTS: Targeting all men who are not exclusively insertive has the largest impact on HIV incidence, but targeting only those with high levels of casual activity yields comparable results using fewer person-years on PrEP. The effect is robust to risk compensation in the United States, but less so in Peru. Targeting serodiscordant main partnerships does not significantly impact incidence, but requires fewer person-years on PrEP per infection averted than other strategies. CONCLUSIONS: PrEP could be effective in reducing new infections at the population level in both settings. Serodiscordant partnerships are an attractive component of a targeting program, but targeting should include other high-risk men.
Assuntos
Transmissão de Doença Infecciosa/prevenção & controle , Infecções por HIV/prevenção & controle , Infecções por HIV/transmissão , Homossexualidade Masculina , Profilaxia Pré-Exposição/métodos , Bioestatística/métodos , Métodos Epidemiológicos , Humanos , Masculino , Peru , Estados UnidosRESUMO
BACKGROUND: Three trials have demonstrated the prophylactic effect of male circumcision (MC) for HIV acquisition among heterosexuals, and MC interventions are underway throughout sub-Saharan Africa. Similar efforts for men who have sex with men (MSM) are stymied by the potential for circumcised MSM to acquire HIV easily through receptive sex and transmit easily through insertive sex. Existing work suggests that MC for MSM should reach its maximum potential in settings where sexual role segregation is historically high and relatively stable across the lifecourse; HIV incidence among MSM is high; reported willingness for prophylactic circumcision is high; and pre-existing circumcision rates are low. We aim to identify the likely public health impact that MC interventions among MSM would have in one setting that fulfills these conditions-Peru-as a theoretical upper bound for their effectiveness among MSM generally. METHODS AND FINDINGS: We use a dynamic, stochastic sexual network model based in exponential-family random graph modeling and parameterized from multiple behavioral surveys of Peruvian MSM. We consider three enrollment criteria (insertive during 100%, >80% or >60% of UAI) and two levels of uptake (25% and 50% of eligible men); we explore sexual role proportions from two studies and different frequencies of switching among role categories. Each scenario is simulated 10 times. We estimate that efficiency could reach one case averted per 6 circumcisions. However, the population-level impact of an optimistic MSM-MC intervention in this setting would likely be at most â¼5-10% incidence and prevalence reductions over 25 years. CONCLUSIONS: Roll-out of MC for MSM in Peru would not result in a substantial reduction in new HIV infections, despite characteristics in this population that could maximize such effects. Additional studies are needed to confirm these results for other MSM populations, and providers may consider the individual health benefits of offering MC to their MSM patients.
Assuntos
Circuncisão Masculina , Surtos de Doenças/prevenção & controle , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Infecções por HIV/epidemiologia , Humanos , Masculino , Modelos Estatísticos , PeruRESUMO
We compared the severity of pediatric inflammatory bowel disease in South Asians with Whites in the US. South Asians more commonly presented with poor weight gain, developed fistulas, and received treatment with antibiotics, methotrexate, adalimumab, and steroids. South Asians appear to have a more complicated presentation and course of pediatric inflammatory bowel disease.
Assuntos
Doenças Inflamatórias Intestinais/diagnóstico , Doenças Inflamatórias Intestinais/etnologia , Adalimumab , Adolescente , Antibacterianos/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Povo Asiático , Bangladesh , California , Criança , Pré-Escolar , Feminino , Fístula/complicações , Humanos , Índia , Lactente , Doenças Inflamatórias Intestinais/terapia , Masculino , Metotrexato/uso terapêutico , Paquistão , Esteroides/uso terapêutico , Estados UnidosRESUMO
In this work, we estimate the proportions of transmissions occurring in main vs. casual partnerships, and by the sexual role, infection stage, and testing and treatment history of the infected partner, for men who have sex with men (MSM) in the US and Peru. We use dynamic, stochastic models based in exponential random graph models (ERGMs), obtaining inputs from multiple large-scale MSM surveys. Parallel main partnership and casual sexual networks are simulated. Each man is characterized by age, race, circumcision status, sexual role behavior, and propensity for unprotected anal intercourse (UAI); his history is modeled from entry into the adult population, with potential transitions including HIV infection, detection, treatment, AIDS diagnosis, and death. We implemented two model variants differing in assumptions about acute infectiousness, and assessed sensitivity to other key inputs. Our two models suggested that only 4-5% (Model 1) or 22-29% (Model 2) of HIV transmission results from contacts with acute-stage partners; the plurality (80-81% and 49%, respectively) stem from chronic-stage partners and the remainder (14-16% and 27-35%, respectively) from AIDS-stage partners. Similar proportions of infections stem from partners whose infection is undiagnosed (24-31%), diagnosed but untreated (36-46%), and currently being treated (30-36%). Roughly one-third of infections (32-39%) occur within main partnerships. Results by country were qualitatively similar, despite key behavioral differences; one exception was that transmission from the receptive to insertive partner appears more important in Peru (34%) than the US (21%). The broad balance in transmission contexts suggests that education about risk, careful assessment, pre-exposure prophylaxis, more frequent testing, earlier treatment, and risk-reduction, disclosure, and adherence counseling may all contribute substantially to reducing the HIV incidence among MSM in the US and Peru.
Assuntos
Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Homossexualidade Masculina/estatística & dados numéricos , Humanos , Masculino , Peru/epidemiologia , Comportamento Sexual , Estados Unidos/epidemiologiaRESUMO
OBJECTIVE: In a randomized multi-center trial, we demonstrated that inhaled nitric oxide begun between 7 and 21 days and given for 24 days significantly increased survival without bronchopulmonary dysplasia (BPD) in ventilated premature infants weighing <1250 g. Because some preventative BPD treatments are associated with neurodevelopmental impairment, we designed a follow-up study to assess the safety of nitric oxide. STUDY DESIGN: Our hypothesis was that inhaled nitric oxide would not increase neurodevelopmental impairment compared with placebo. We prospectively evaluated neurodevelopmental and growth outcomes at 24 months postmenstrual age in 477 of 535 surviving infants (89%) enrolled in the trial. RESULTS: In the treated group, 109 of 243 children (45%) had neurodevelopmental impairment (moderate or severe cerebral palsy, bilateral blindness, bilateral hearing loss, or score <70 on the Bayley Scales II), compared with 114 of 234 (49%) in the placebo group (relative risk, 0.92; 95% CI, 0.75-1.12; P = .39). No differences on any subcomponent of neurodevelopmental impairment or growth variables were found between inhaled nitric oxide or placebo. CONCLUSIONS: Inhaled nitric oxide improved survival free of BPD, with no adverse neurodevelopmental effects at 2 years of age.