Medication Non-adherence and Condomless Anal Intercourse Increased Substantially During the COVID-19 Pandemic Among MSM PrEP Users: A Retrospective Cohort Study in Four Chinese Metropolises.

Background: The coronavirus disease (COVID-19) pandemic has impacted HIV prevention strategies globally. However, changes in pre-exposure prophylaxis (PrEP) adherence and HIV-related behaviors, and their associations with medication adherence among men who have sex with men (MSM) PrEP users remain unclear since the onset of the COVID-19 pandemic. Methods: A Retrospective Cohort Study of HIV-negative MSM PrEP users was conducted in four Chinese metropolises from December 2018 to March 2020, assessing the changes in PrEP adherence and HIV-related behaviors before and during the COVID-19. The primary outcome was poor PrEP adherence determined from self-reported missing at least one PrEP dose in the previous month. We used multivariable logistic regression to determine factors correlated with poor adherence during COVID-19. Results: We enrolled 791 eligible participants (418 [52.8%] in daily PrEP and 373 [47.2%] in event-driven PrEP). Compared with the data conducted before the COVID-19, the proportion of PrEP users decreased from 97.9 to 64.3%, and the proportion of poor PrEP adherence increased from 23.6 to 50.1% during the COVID-19 [odds ratio (OR) 3.24, 95% confidence interval (CI) 2.62-4.02]. While the percentage of condomless anal intercourse (CAI) with regular partners (11.8 vs. 25.7%) and with casual partners (4.4 vs. 9.0%) both significantly increased. The proportion of those who were tested for HIV decreased from 50.1 to 25.9%. Factors correlated with poor PrEP adherence during the COVID-19 included not being tested for HIV (adjusted odds ratio [aOR] = 1.38 [95% CI: 1.00, 1.91]), using condoms consistently with regular partners (vs. never, aOR = 2.19 [95% CI: 1.16, 4.13]), and being married or cohabitating with a woman (vs. not married, aOR = 3.08 [95% CI: 1.60, 5.95]). Conclusions: Increased poor PrEP adherence and CAI along with the decrease in HIV testing can lead to an increase in HIV acquisition and drug resistance to PrEP. Targeted interventions are needed to improve PrEP adherence and HIV prevention strategies.

The efficacy of low-dose aspirin in pregnancy among women in malaria-endemic countries.

BACKGROUND: Low dose aspirin (LDA) is an effective strategy to reduce preterm birth. However, LDA might have differential effects globally, based on the etiology of preterm birth. In some regions, malaria in pregnancy could be an important modifier of LDA on birth outcomes and anemia. METHODS: This is a sub-study of the ASPIRIN trial, a multi-national, randomized, placebo controlled trial evaluating LDA effect on preterm birth. We enrolled a convenience sample of women in the ASPIRIN trial from the Democratic Republic of Congo (DRC), Kenya and Zambia. We used quantitative polymerase chain reaction to detect malaria. We calculated crude prevalence proportion ratios (PRs) for LDA by malaria for outcomes, and regression modelling to evaluate effect measure modification. We evaluated hemoglobin in late pregnancy based on malaria infection in early pregnancy. RESULTS: One thousand four hundred forty-six women were analyzed, with a malaria prevalence of 63% in the DRC site, 38% in the Kenya site, and 6% in the Zambia site. Preterm birth occurred in 83 (LDA) and 90 (placebo) women, (PR 0.92, 95% CI 0.70, 1.22), without interaction between LDA and malaria (p = 0.75). Perinatal mortality occurred in 41 (LDA) and 43 (placebo) pregnancies, (PR 0.95, 95% CI 0.63, 1.44), with an interaction between malaria and LDA (p = 0.014). Hemoglobin was similar by malaria and LDA status. CONCLUSIONS: Malaria in early pregnancy did not modify the effects of LDA on preterm birth, but modified the effect of LDA on perinatal mortality. This effect measure modification deserves continued study as LDA is used in malaria endemic regions.

Predictors of Plasmodium falciparum Infection in the First Trimester Among Nulliparous Women From Kenya, Zambia, and the Democratic Republic of the Congo.

BACKGROUND: Malaria can have deleterious effects early in pregnancy, during placentation. However, malaria testing and treatment are rarely initiated until the second trimester, leaving pregnancies unprotected in the first trimester. To inform potential early intervention approaches, we sought to identify clinical and demographic predictors of first-trimester malaria. METHODS: We prospectively recruited women from sites in the Democratic Republic of the Congo (DRC), Kenya, and Zambia who participated in the ASPIRIN (Aspirin Supplementation for Pregnancy Indicated risk Reduction In Nulliparas) trial. Nulliparous women were tested for first-trimester Plasmodium falciparum infection by quantitative polymerase chain reaction. We evaluated predictors using descriptive statistics. RESULTS: First-trimester malaria prevalence among 1513 nulliparous pregnant women was 6.3% (95% confidence interval [CI], 3.7%-8.8%] in the Zambian site, 37.8% (95% CI, 34.2%-41.5%) in the Kenyan site, and 62.9% (95% CI, 58.6%-67.2%) in the DRC site. First-trimester malaria was associated with shorter height and younger age in Kenyan women in site-stratified analyses, and with lower educational attainment in analyses combining all 3 sites. No other predictors were identified. CONCLUSIONS: First-trimester malaria prevalence varied by study site in sub-Saharan Africa. The absence of consistent predictors suggests that routine parasite screening in early pregnancy may be needed to mitigate first-trimester malaria in high-prevalence settings.

Assisted Partner Notification and Uptake of HIV Testing among Men Who Have Sex with Men: A Randomized Controlled Trial in China.

BACKGROUND: Assisted partner notification (PN) is an effective approach for increasing HIV testing among heterosexual partners. There is sparse evidence on its effect among sexual partners of men who have sex with men (MSM). METHODS: A randomized controlled trial was conducted to compare the effect of assisted PN and passive PN interventions on uptake of HIV testing among male and female sexual partners of newly HIV-diagnosed MSM. In the passive PN group, participants were encouraged to disclose their HIV status and refer and persuade sexual partners to access HIV testing services (HTS). In the assisted PN group, participants were further provided with HIV self-testing kits for sexual partners to take a test at home or allow a community health worker from MSM-serving community-based organization (CBO) to anonymously refer and persuade their sexual partners to access HTS. The primary outcome was the proportion of index cases who had any sexual partner accessing HTS within four months after randomization. This trial is registered with chictr.org.cn, ChiCTR1800017813. FINDINGS: Between August 2017 and January 2019, 187 MSM newly diagnosed with HIV in a large city Shenyang in northern China were enrolled in the study and randomly assigned to either passive PN (n=90) or assisted PN (n=97) study groups. The proportion of index cases who disclosed their HIV status to any sexual partners within three months of randomization was similar between passive PN (57%, 95% confidence interval [CI]: 46-67%) and assisted PN groups (58%, 95% CI: 48-68%). During four months of follow-up, the number of sexual partners named, referred to HTS, tested and testing positive per index case was 3•2, 0•7, 0•2 and 0•03 in the passive PN group, and 4•0, 1•0, 0•5 and 0•10 in the assisted PN group. Thirty-five percent of index cases in the assisted PN group had any sexual partners accessing HIV testing compared to 17% in the passive PN group (P = 0•004); 49% sexual partners who were disclosed by index cases in the assisted PN group had access HTS compared to 28% in the passive PN group (P = 0•007). INTERPRETATION: The assisted PN strategy incorporating HIV self-testing and CBO outreach can increase uptake of HIV testing among sexual partners of MSM who were recently diagnosed with HIV. FUNDING: National Science and Technology Major Project of China, National Natural Science Foundation of China, and Project for Overseas Visiting Research of Liaoning Province.

Factors Influencing Clinicians' Willingness to Prescribe Pre-exposure Prophylaxis for Persons at High Risk of HIV in China: Cross-sectional Online Survey Study.

BACKGROUND: Pre-exposure prophylaxis (PrEP) is an effective HIV prevention measure. Clinicians play a crucial role in PrEP implementation, and their knowledge, attitudes, and career experience may affect their willingness to prescribe PrEP. However, little is known about the attitudes and willingness of clinicians to prescribe PrEP in countries without PrEP-specific guidelines. OBJECTIVE: We aimed to determine the factors associated with clinicians being willing to prescribe PrEP in China. METHODS: Between May and June 2019, we conducted an online cross-sectional survey of clinicians in 31 provinces across the six administrative regions in China on the WeChat smartphone app platform. Multivariable logistic regression was used to determine factors associated with willingness to prescribe PrEP. RESULTS: Overall, 777 HIV clinicians completed the survey. Most of the respondents had heard of PrEP (563/777, 72.5%), 31.9% (248/777) thought that PrEP was extremely effective for reducing the risk of HIV infection, and 47.2% (367/777) thought that it was necessary to provide PrEP to high-risk groups. After adjusting for age, gender, ethnicity, and educational background of the clinicians, the following factors significantly increased the odds of the clinicians being willing to prescribe PrEP: having worked for more than 10 years, compared to 5 years or less (adjusted odds ratio [aOR] 2.82, 95% CI 1.96-4.05); having treated more than 100 patients living with HIV per month, compared to 50 patients or fewer (aOR 4.16, 95% CI 2.85-6.08); and having heard of PrEP (aOR 7.32, 95% CI 4.88-10.97). Clinicians were less likely to be willing to prescribe PrEP if they were concerned about poor adherence to PrEP (aOR 0.66, 95% CI 0.50-0.88), the lack of PrEP clinical guidelines (aOR 0.47, 95% CI 0.32-0.70), and the lack of drug indications for PrEP (aOR 0.49, 95% CI 0.32-0.76). CONCLUSIONS: About half of all clinicians surveyed were willing to prescribe PrEP, but most surveyed had a low understanding of PrEP. Lack of PrEP clinical guidelines, lack of drug indications, and less than 11 years of work experience were the main barriers to the surveyed clinicians' willingness to prescribe PrEP. Development of PrEP clinical guidelines and drug indications, as well as increasing the availability of PrEP training, could help improve understanding of PrEP among clinicians and, thus, increase the number willing to prescribe PrEP.

Use of multiple recreational drugs is associated with new HIV infections among men who have sex with men in China: a multicenter cross-sectional survey.

BACKGROUND: There is limited information about the types of recreational drugs used by men who have sex with men (MSM) in China or the consequent impact on sexual health and human immunodeficiency virus (HIV) acquisition. METHODS: We recruited MSM from seven cities in China between 2012 and 2013 using multiple approaches including advertisements on gay websites, collaborating with local MSM community-based organizations, peer referrals, and venues such as gay bars and bathrooms visited by MSM. We divided participants into four subgroups based on the number of recreational drugs (RDs) used in the previous 6 months. We defined use of multiple RDs as use of ≥2 types of RDs. Demographics and HIV-related high-risk behaviors were collected, and blood samples were tested for recent HIV infection by the HIV-1 subtypes B, E, and D immunoglobulin G capture enzyme immunoassay (BED-CEIA). We used multivariable logistic regression adjusted for sociodemographics to determine the adjusted odds ratios (aORs) and associated 95% confidence intervals (CIs) of the subgroups of RD use for recent or established HIV infection. RESULTS: A total of 4496 Chinese MSM participated; 28.4% used RDs, and 5% used multiple types of RDs. The prevalence of each RD use was as follows: poppers (25.9%), ecstasy (2.4%), ketamine (1.2%), amphetamine (0.6%), tramadol (0.4%), methamphetamine (3.8%), and codeine (1.9%). Users of multiple RDs commonly used poppers combined with one or more other types of RDs. Multiple RD users were likely to be aged 26-30 years (vs. 18-25 and > 30 years), live in non-local cities (vs. local cities), never married (vs. married), have a high monthly income (vs. no income and 1-599 USD), use versatile positions during anal intercourse (vs. top or bottom), and have inadequate HIV-related prevention knowledge (vs. adequate). As the number of RDs used in the previous 6 months increased, the prevalence of HIV-related high-risk behaviors increased (P < 0.05 for all). The odds of recent HIV infection were higher among those who used one type (aOR = 2.2, 95% CI: 1.5-3.0) or two types of RD (aOR=2.3, 95% CI: 1.0-5.2) in the previous 6 months compared to the odds among those who did not use RDs. CONCLUSION: The level and pattern of multiple RD use among Chinese MSM were different from high-income countries. MSM who used more RDs are more likely to engage in high-risk sexual behaviors, and these behaviors may be associated with increases in new HIV infections.

Frequently Transmission and Close Relationship Among Immigrants in the China-Myanmar Border Region Indicated by Molecular Transmission Analysis From a Cross-Sectional Data.

Background: Accurate identification of molecular transmission clusters (MTCs) and understanding the dynamics of human immunodeficiency virus (HIV) transmission are necessary to develop targeted interventions to prevent HIV transmission. We evaluated the characteristics of antiretroviral therapy-naïve individuals who belonged to HIV-1 MTCs in the China-Myanmar border region to inform targeted effective HIV intervention. Methods: Phylogenetic analyses were undertaken on HIV-1 pol sequences to characterize subtypes or circulating recombinant forms and identify MTCs. MTCs were defined as those with 2 or more sequences having bootstrap support > 80% and a pairwise gene distance less than or equal to 0.03. Factors correlated with MTCs were evaluated using logistic regression analysis. The chi-square test was used to compare differences between Chinese and Burmese participants belonging to MTCs. Results: A total of 900 people had their pol gene successfully sequenced. Twenty-one MTCs were identified and included 110 individuals (12.2%). Individuals in MTCs were more likely to be Burmese [aOR = 2.24 (95% CI: 1.33, 3.79), P = 0.003], be younger [aOR = 0.34 (95% CI: 0.20, 0.58), P < 0.001 for age 26-50 vs. 25 years or younger], have a lower CD4 T cell count [aOR = 2.86 (95% CI: 1.34, 6.11), P = 0.007 for < 200 vs. 350 or greater], and have subtypes CRF07_BC or C [CRF07_BC: aOR = 7.88 (95% CI: 3.55, 17.52), P < 0.001; C: aOR = 2.38 (95% CI: 1.23, 4.62), P = 0.010 compared to CRF01_AE]. In MTCs, Burmese were younger (89.7 vs. 57.7% for age 25 years or younger), had a lower education level (41.0 vs. 8.5% for illiterate), were more likely to be infected through injection drug use (35.9 vs. 12.7%), and had a higher proportion of subtype BC (33.3 vs. 15.5%) and CRF01_AE (20.5 vs. 8.5%) compared to Chinese (P < 0.05 for all). Conclusion: Burmese participants were more likely to belong to MTCs, and most MTCs had both Burmese and Chinese participants. These data highlight the bidirectional transmission of HIV-1 frequently transmission and close relationship among immigrants in the China-Myanmar border region. Local health departments should pay more attention to HIV screening and intervention to immigrants Burmese with the characteristics of younger age, having lower CD4 T cell count and infected with HIV subtypes CRF07_ BC or C.

Tracking and predicting U.S. influenza activity with a real-time surveillance network.

Each year in the United States, influenza causes illness in 9.2 to 35.6 million individuals and is responsible for 12,000 to 56,000 deaths. The U.S. Centers for Disease Control and Prevention (CDC) tracks influenza activity through a national surveillance network. These data are only available after a delay of 1 to 2 weeks, and thus influenza epidemiologists and transmission modelers have explored the use of other data sources to produce more timely estimates and predictions of influenza activity. We evaluated whether data collected from a national commercial network of influenza diagnostic machines could produce valid estimates of the current burden and help to predict influenza trends in the United States. Quidel Corporation provided us with de-identified influenza test results transmitted in real-time from a national network of influenza test machines called the Influenza Test System (ITS). We used this ITS dataset to estimate and predict influenza-like illness (ILI) activity in the United States over the 2015-2016 and 2016-2017 influenza seasons. First, we developed linear logistic models on national and regional geographic scales that accurately estimated two CDC influenza metrics: the proportion of influenza test results that are positive and the proportion of physician visits that are ILI-related. We then used our estimated ILI-related proportion of physician visits in transmission models to produce improved predictions of influenza trends in the United States at both the regional and national scale. These findings suggest that ITS can be leveraged to improve "nowcasts" and short-term forecasts of U.S. influenza activity.

Association of nitrite inhalants use and unprotected anal intercourse and HIV/syphilis infection among MSM in China: a systematic review and meta-analysis.

BACKGROUND: Nitrite inhalant use is very common among men who have sex with men (MSM) in China. However, there is lack of national representative data on use among Chinese MSM, and the mechanism of how nitrite inhalant use impacts HIV infection in MSM is unclear. This meta-analysis aims to understand the characteristics of Chinese MSM nitrite inhalant users and to determine the associations between nitrite inhalant use and sexual behaviors, the prevalence of HIV, and the prevalence of syphilis. METHODS: We searched PubMed, Web of Science, Chinese National Knowledge Infrastructure, Chinese Wanfang Data, and VIP Chinese Journal Database for relevant literature published from January 1985 to December 2017. RESULTS: Fifteen eligible studies, with a total of 18,981 Chinese MSM participants, were included. Compared with nitrite inhalant nonusers, users were more likely to be younger, have a higher level of education, and seek sexual partners using the Internet. Nitrite inhalant users were more likely to engage in high-risk sexual behaviors, including condomless anal intercourse (odds ratio [OR] = 1.33), group sex (OR = 2.26), and commercial intercourse (OR = 1.50). Nitrite inhalants users had a higher prevalence of HIV (OR = 1.83), higher prevalence of syphilis (OR = 1.38) and had higher lifetime HIV testing rates (OR = 1.33) compared with nonusers (each p < 0.05). CONCLUSIONS: Nitrite inhalant users have higher HIV and syphilis prevalence by increasing levels of high-risk sexual behaviors. China should expand HIV testing, treatment as prevention (TasP), and Pre-exposure prophylaxis (PrEP) among MSM, especially among nitrite inhalants using MSM, to reduce their risk of HIV infection and transmission.

Increasing Condomless Anal Intercourse and HIV Prevalence Among Men Who Have Sex with Men Who Have Never Been Tested for HIV Before: A Serial Cross-Sectional Study in Shenyang, China from 2012 to 2016.

Despite the high HIV incidence among men who have sex with men (MSM) in China, over half of MSM have never been tested for HIV before (MSMNT). Through a serial cross-sectional study from 2012 to 2016 in Shenyang, China, we studied 1036 MSMNT, and diagnosed 16.2% (168/1036) with HIV. The percentage of MSMNT who had condomless anal intercourse (CAI) in the past year increased from 42.1% (130/309) in 2012 to 63.4% (102/161) in 2016 (P < 0.001). 61.9% (104/168) of HIV-positive MSMNT had CAI and this percentage remained constant for the study period (P = 0.593). 53.3% (463/868) of HIV-negative MSMNT had CAI and this percentage significantly increased over the study period (P < 0.001). Encouraging HIV testing in this key subset through online HIV risk self-evaluation tools and HIV self-testing kits may help mitigate the overall MSM HIV incidence.

Protocol for a multicenter, real-world study of HIV pre-exposure prophylaxis among men who have sex with men in China (CROPrEP).

BACKGROUND: Pre-exposure prophylaxis (PrEP) is a promising and effective tool to prevent human immunodeficiency virus (HIV) transmission; however, context-specific data to guide optimal implementation are currently lacking in China. This study aims to systematically collect comprehensive, empirical data to determine effective ways to implement PrEP among at-risk men who have sex with men (MSM) in China. METHODS: The CROPrEP project, a real-world study of PrEP use, will recruit 1000 high-risk HIV-negative MSM participants from four cities in China, who will be able to choose between daily or event-driven dosing regimens, according to their preference. Participants will be followed up at months 1, 3, 6, 9, and 12 for PrEP provision, clinical evaluation, laboratory testing (e.g., emtricitabine/tenofovir disoproxil fumarate (FTC/TDF) concentrations, and HIV/sexually transmitted infections), alongside detailed, self-administered online questionnaires regarding sexual behaviors, adherence, and attitudes. Online weekly notes will be used to record pill use and sexual practice. Various measurements will be triangulated to assess adherence, including: self-reported adherence, pill count, and drug concentration. A propensity score matching model will be fitted to examine the effectiveness of PrEP use in HIV seroconversion compared with non-PrEP users selected from a local expanding cohort study of HIV-1-negative MSM at participating research centers. Analyses using a generalized estimating equation model will focus on elucidation of the cascade of PrEP implementation, effectiveness, safety, and possible effects of PrEP use on sexual behaviors. This study will provide a comprehensive assessment of real-world PrEP use among Chinese MSM, to develop guidelines and strategies for PrEP implementation in China. DISCUSSION: The CROPrEP project is the first study of the TDF/FTC combination as PrEP in China, which will provide primary data on PrEP implementation, including: the cascade of PrEP use, "real-world" effectiveness, adherence, and safety. The findings from this study have potential to be vital for promoting the integration of PrEP within the portfolio of HIV prevention interventions and developing guidance on PrEP implementation in China. TRIAL REGISTRATION: ChiCTR-IIN-17013762 (Chinese Clinical Trial Registry). Date of registration: 8 December 2017.

Recalling, Sharing and Participating in a Social Media Intervention Promoting HIV Testing: A Longitudinal Analysis of HIV Testing Among MSM in China.

Social media interventions may enhance HIV services among key populations, including men who have sex with men (MSM). This longitudinal analysis examined the effect of recalling, sharing, and participating in different components of a social media intervention on HIV testing among MSM. The social media intervention included six images/texts and information about an online local community contest to promote testing. Of the 1033 men, they recalled a mean of 2.7 out of six images and shared an average of one image online. 34.5% of men recalled information on the online local community contest and engaged in a mean of 1.3 contest. Recalling images/texts (aOR = 1.13, 95% CI 1.02-1.25) and recalling a local contest (aOR = 1.59, 95% CI 1.13-1.24) were associated with facility-based HIV testing. This study has implications for the development and evaluation of social media interventions to promote HIV testing.

Accurate quantification of uncertainty in epidemic parameter estimates and predictions using stochastic compartmental models.

Stochastic transmission dynamic models are needed to quantify the uncertainty in estimates and predictions during outbreaks of infectious diseases. We previously developed a calibration method for stochastic epidemic compartmental models, called Multiple Shooting for Stochastic Systems (MSS), and demonstrated its competitive performance against a number of existing state-of-the-art calibration methods. The existing MSS method, however, lacks a mechanism against filter degeneracy, a phenomenon that results in parameter posterior distributions that are weighted heavily around a single value. As such, when filter degeneracy occurs, the posterior distributions of parameter estimates will not yield reliable credible or prediction intervals for parameter estimates and predictions. In this work, we extend the MSS method by evaluating and incorporating two resampling techniques to detect and resolve filter degeneracy. Using simulation experiments, we demonstrate that an extended MSS method produces credible and prediction intervals with desired coverage in estimating key epidemic parameters (e.g. mean duration of infectiousness and R0) and short- and long-term predictions (e.g. one and three-week forecasts, timing and number of cases at the epidemic peak, and final epidemic size). Applying the extended MSS approach to a humidity-based stochastic compartmental influenza model, we were able to accurately predict influenza-like illness activity reported by U.S. Centers for Disease Control and Prevention from 10 regions as well as city-level influenza activity using real-time, city-specific Google search query data from 119 U.S. cities between 2003 and 2014.

The Effect of Using Geosocial Networking Apps on the HIV Incidence Rate Among Men Who Have Sex With Men: Eighteen-Month Prospective Cohort Study in Shenyang, China.

BACKGROUND: Men who have sex with men (MSM) frequently seek partners through mobile apps (geosocial networking [GSN] apps). However, it is unclear whether GSN apps' use is associated with the increase in HIV incidence among MSM. OBJECTIVE: The aim of this study was to clarify the characteristics of GSN apps' users and to determine the association and putative mechanisms between GSN apps' use behavior and HIV incidence. METHODS: We conducted an 18-month prospective cohort study of MSM in Shenyang, China, and the participants were surveyed every 3 months from March 2015 to December 2016. An in-person interview collected information on sociodemographics, GSN apps' use, recreational drug use, and sexual behaviors. In addition, blood was drawn to test for HIV and syphilis. We used a multivariable Cox regression model to determine possible predictors for increased HIV incidence. RESULTS: Of the enrolled 686 HIV-negative MSM, 431 (431/686, 62.8%) were GSN apps' users. Compared with GSN apps' nonusers, GSN apps' users were younger; had an earlier age of sexual debut; and in the past 3 months, were more likely to have used recreational drugs, more likely to have had 5 or more casual partners (CPs), more likely to have had group sex with males, and more likely to have had condomless anal intercourse (CAI) with male steady partners (SPs). In addition, 59.4% (256/431) of the GSN apps' users were willing to accept HIV and AIDS prevention information push services through GSN apps. In total, 19 MSM seroconverted to HIV during the follow-up period; the HIV incidence density rate was 8.5 (95% CI 5.0-13.5) per 100 person-years (PY) among GSN apps' users and 2.0 (95% CI 0.4-5.8) per 100 PY among nonusers. New HIV infections were independently associated with ever using GSN apps to seek male sexual partners (P=.04) and in the past 3 months, using recreational drugs (P=.048), having group sex with males (P=.01), and having CAI with male CPs (P=.02). CONCLUSIONS: GSN apps' use is associated with higher HIV incidence and may be mediated through recreational drug use and having multiple CPs. Researchers must develop an intervention propagated through GSN apps to reach this high-risk population to mitigate the HIV epidemic in the MSM community.

Use of daily Internet search query data improves real-time projections of influenza epidemics.

Seasonal influenza causes millions of illnesses and tens of thousands of deaths per year in the USA alone. While the morbidity and mortality associated with influenza is substantial each year, the timing and magnitude of epidemics are highly variable which complicates efforts to anticipate demands on the healthcare system. Better methods to forecast influenza activity would help policymakers anticipate such stressors. The US Centers for Disease Control and Prevention (CDC) has recognized the importance of improving influenza forecasting and hosts an annual challenge for predicting influenza-like illness (ILI) activity in the USA. The CDC data serve as the reference for ILI in the USA, but this information is aggregated by epidemiological week and reported after a one-week delay (and may be subject to correction even after this reporting lag). Therefore, there has been substantial interest in whether real-time Internet search data, such as Google, Twitter or Wikipedia could be used to improve influenza forecasting. In this study, we combine a previously developed calibration and prediction framework with an established humidity-based transmission dynamic model to forecast influenza. We then compare predictions based on only CDC ILI data with predictions that leverage the earlier availability and finer temporal resolution of Wikipedia search data. We find that both the earlier availability and the finer temporal resolution are important for increasing forecasting performance. Using daily Wikipedia search data leads to a marked improvement in prediction performance compared to weekly data especially for a three- to four-week forecasting horizon.