Search

Background: While global efforts are increasingly relying upon biomedical advancements such as antiretroviral therapy and pre-exposure prophylaxis (PrEP) to end the HIV epidemic, HIV-related stigma remains a concern. This study aimed to assess the general public's awareness and perception of "Undetectable = Untransmittable" (U = U) and PrEP, and the patterns of public stigma towards people living with HIV (PLWH) and their determinants in an Asian Pacific city. Methods: A population-based, self-administrated online survey was conducted between 10–20 March 2023. All adults aged ≥ 18 years and currently living in Hong Kong were eligible. Participants' socio-demographic characteristics, awareness and perception of U = U and PrEP, as well as HIV-related stigma drivers, experience and practices were collected. Latent class analysis was used to delineate population subgroups based on their stigma profiles as reflected by 1.) fear of infection, 2.) concern about socioeconomic ramification of the disease, 3.) social norm enforcement, 4.) perceived stigma in the community, and 5.) stigmatising behaviours and discriminatory attitudes. Memberships of identified subgroups were then correlated with sociodemographic factors, awareness and perception of U = U and PrEP, using multinominal logistic regression. Results: Responses from a total of 3070 participants (55% male; 79% aged 18–54) were analysed. A majority, 69% and 81%, indicated that they had never heard of U = U and PrEP respectively, and only 39–40% of participants perceived these to be effective in protection from HIV. Four distinct subgroups were identified, namely "Low stigma" (37%), "Modest stigma" (24%), "Moderate stigma" (24%), and "High stigma" (15%). Compared with "Low stigma", lack of awareness of and/or negative perceptions towards U = U and/or PrEP, not knowing any PLWH were associated with increased odds of higher stigma group membership. Lower educational level and not in employment were associated with increased odds of membership in "Moderate stigma" and "High stigma". While older people were more likely to belong to "High stigma", female were more likely to belong to "Moderate stigma". "Modest stigma" included more younger people who were economically active. Conclusion: Two-thirds of participants endorsed modest-to-high HIV-related stigma, suggesting the prevalence of HIV-related stigma was high among the general population in Hong Kong. Tailored interventions targeting specific stigma drivers and manifestations of individuals as reflected from the stigma profiles of distinct subgroups could form an important strategy for stigma reduction. [ABSTRACT FROM AUTHOR]

Purpose: To detect otherwise undiagnosed asymptomatic sexually transmitted infection (STI), and for estimating prevalence among men who have sex with men (MSM). Methods: In this community-based study in Hong Kong, adult MSM were recruited. After completion of an online survey, free multi-anatomic sites self-sampling kits (urine specimens, pharyngeal and rectal swabs) for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) tests were delivered to requesting participants. Factors associated with STI positivity were analyzed in logistic regression. Results: From September 2021 to October 2022, 712 MSM were recruited, with 86% aged 18–39, and 16% reported history of chemsex engagement. A majority (81%) had previously undergone HIV testing, 68% had ever tested for STI, and 35% previously diagnosed with STI. Totally 428 (60%) had requested self-sampling kits, and 276 (39%) returned collected samples. Among participants who returned the samples, about half had never been tested in the past and had no history of STI. Overall 21% tested positive for CT and/or NG (CT/NG)—CT positive 16% and NG positive 7%. By anatomic site, 16% of rectal swabs, 7% of pharyngeal swabs, but just 3% of urine specimens were CT/NG positive. The prevalence of CT/NG was not significantly different by history of STI diagnosis and testing. Conclusion: Self-sampled STI testing is a potentially useful means for enhancing uptake of screening in MSM in the community, which could uncover otherwise undiagnosed asymptomatic infections. Internet-based self-sampling for STI testing could complement the current clinic-based STI testing for supporting epidemiologic evaluation of STI control in the community. [ABSTRACT FROM AUTHOR]

Pre-exposure prophylaxis (PrEP) use has been shown to be effective for HIV prevention in men who have sex with men (MSM). PrEP use coverage aside, maintenance of high PrEP adherence is crucial in ensuring the achievement of HIV prevention. In this PrEP implementation study in Hong Kong, we examined the patterns of PrEP use in MSM and evaluated their association with prevention-effective adherence for HIV prevention. In January 2020–June 2021 in Hong Kong, 312 recruited MSM (median 30 years old) were followed up for 1 year, with HIV and creatinine testing, consultation, and PrEP refill. No HIV breakthrough infection was observed. As a measure of prevention-effective adherence, executed adherence (EA) was expressed as the proportion of days with HIV risk that were protected by PrEP and/or condom in 6 months. In 65,585 diary entries of 215 MSM, the median proportion of EA achieved was 89% (IQR 84–93%). Three latent classes of PrEP users were identified by latent class analysis. Taking Class 1 "daily dominant PrEP" (n = 113, 53%) as reference, Class 2 "episodic PrEP" (n = 76, 35%) was adopted by MSM with less sexual activity, had less PrEP refill and lower EA level, while Class 3 "mixed PrEP schedule" (n = 26, 12%) MSM were more sexually active but with a similar EA level. The study findings showed varied and dynamic PrEP usage patterns in the real-world setting. Strategies for promoting adherence are needed to ensure the maintenance of high EA level among PrEP-using MSM especially those on episodic PrEP schedule. [ABSTRACT FROM AUTHOR]

Hong Kong is an Asia-Pacific City with low incidence but periodic local outbreaks of dengue. A mixed-method assessment of the risk of expansion of dengue endemicity in such setting was conducted. Archived blood samples of healthy adult blood donors were tested for anti-dengue virus IgG at 2 time-points of 2014 and 2018/2019. Data on the monthly notified dengue cases, meteorological and vector (ovitrap index) variables were collected. The dengue virus (DENV) IgG seroprevalence of healthy adults in 2014 was 2.2% (95%C.I. = 1.8–2.8%, n = 3827) whereas that in 2018/2019 was 1.7% (95%C.I. = 1.2–2.3%, n = 2320). Serotyping on 42 sera in 2018/2019 showed that 22 (52.4%) were DENV-2. In 2002–2019, importation accounted for 95.3% of all reported cases. By wavelet analysis, local cases were in weak or no association with meteorological and vector variables. Without strong association between local cases and meteorological/vector variables, there was no evidence of increasing level of dengue infection in Hong Kong. [ABSTRACT FROM AUTHOR]

Exposure setting is crucial in the formation and propagation of SARS-CoV-2 transmission clusters. In this cohort study, transmission networks of 2 waves were differentiated by exposure setting using territory-wide surveillance data with clinical and laboratory records in Hong Kong. Characteristically, the first wave had resulted from imported cases followed by local transmissions, while the second wave was constituted primarily by local infections. With a 4-fold higher caseload, the second wave featured predominance of epidemiologically linked, local, older and asymptomatic patients with higher viral loads and shorter inpatient days. The 1028 transmission clusters formed 155 cascades composing at least two clusters. Daily and social activities were exposure settings that bridged clusters while residences usually terminated transmission cascades. Regulatory restrictions on social activities extinguished cluster formation in bars, but shifted to private parties in the second wave. The results confirmed that strategic interventions targeting exposure settings could achieve effective epidemic control. [ABSTRACT FROM AUTHOR]

Worldwide, the COVID-19 pandemic has disrupted influenza seasonality and impacted influenza vaccination behaviours. This study examines the patterns of influenza vaccination uptake in nurses during the pre-pandemic seasons and amidst the pandemic in 2020/21 in subtropical Hong Kong. In April 2021, a cross-sectional survey was conducted in practising and student nurses. Six patterns were differentiated by their influenza vaccination status in 2020/21 and preceding five seasons: (a) resistance throughout, (b) negative change, (c) decreased tendency, (d) increased tendency (e) positive change, and (f) adherence throughout. Participants' characteristics and reasons for vaccination/non-vaccination and their associations with each vaccination pattern were explored using multivariable multinomial regression. Among 1323 nurses (88% female with a median age of 39 years), no substantial change in vaccination uptake was noted from 2019/20 (41%) to 2020/21 (42%). Some 4% were positive-changers who were older at age of ≥50 years (aOR 4.77) and more likely to anticipate a reduced risk of severe disease with COVID-19/influenza co-infection following vaccination (aOR 8.76). Negative-changers made up 3% and were more inclined to perceive an unlikelihood of widespread influenza outbreaks amidst the pandemic (aOR 3.67). Some 26 and 43% remained adherent and resistant to influenza vaccination throughout respectively notwithstanding the COVID-19 outbreak. In contrast to the increased uptake elsewhere, the stable influenza vaccination coverage among nurses in Hong Kong could be explained by the ubiquity of strict physical distancing regulations, which have deterred vaccination in some nurses that offsets the new uptakes induced by the mild COVID-19 outbreaks. [ABSTRACT FROM AUTHOR]

Objectives: To assess impacts of early detection and prompt antiretroviral therapy (ART) on the latest epidemiologic situation to inform intervention strategy. Methods: We analysed data from two clinical cohorts in Hong Kong where sexual transmission accounted for the majority of HIV infections. The two cohorts comprised patients newly diagnosed in 2007–2008 and 2016–2018 respectively. Secular trend and differences between men who have sex with men (MSM) and heterosexual patients were examined. Predictors of late presentation (defined as CD4 ≤350 or AIDS-defining illness within 3 months of diagnosis) and prolonged interval between diagnosis and ART initiation were assessed by multivariable regressions. Results: There were 1,136 newly diagnosed HIV patients with 644 in the first and 492 in the second cohort, a majority (91.7%) presented with sexually acquired infection. There were less MSM in the first than the second cohort (50.3%% vs 87.8%, χ2 = 117.05, p<0.001). The mean (SD) number of days between diagnosis and ART initiation decreased from 514.3 (516.1) to 61.8 (94.2) days across the two cohorts. Younger age, non-Chinese, outpatient-based service and lower CD4 count were predictors of faster ART initiation in the first but not in the second cohort. Interval between diagnosis and ART initiation became highly uniform among groups in the second cohort. Nearly 60% were classified as late presenters in both cohorts. Heterosexuals (aOR 1.58, 95% CI 1.13–2.19) had a higher risk of late presentation. Conclusions: There was remarkable improvement in acceleration of ART initiation. Clinical implementation of accelerated ART recommendations has been effective for both MSM and heterosexuals. Late presentation was more marked among heterosexuals and remained a problem. The continued phenomenon of late presentation could offset the epidemiologic gains from accelerated ART initiation. [ABSTRACT FROM AUTHOR]

Background: Human immunodeficiency virus (HIV) functional cure is a novel biomedical strategy characterized by sustained viral suppression without the need for life-long medications. The attitude of people living with HIV (PLHIV) towards functional cure and clinical trials are understudied. We aimed to examine the awareness and levels of anticipation for HIV functional cure among men who have sex with men (MSM) living with HIV, and their willingness to join trials as differentiated by their antiretroviral treatment status.Methods: MSM living with HIV with and those without treatment history were recruited from Hong Kong's HIV specialist clinics. Self-administered questionnaires covering behavioral profile, perceived impact of HIV cure, attitude towards HIV functional cure and related clinical trials were collected. Clinical data were separately transcribed. Determinants of perceptions and attitudes were identified by logistic regression models.Results: Of 356 MSM living with HIV recruited, less than half (42%) were aware of HIV functional cure, but they had a high level of anticipation for it. Treatment-experienced participants were more likely to be aware of HIV functional cure. Awareness was associated with continued engagement in sexual activities after HIV diagnosis and sexually transmitted infection (STI) diagnosis. Higher anticipation was observed among older MSM living with HIV but it was negatively associated with one's awareness. Over 90% were willing to join functional cure trials, especially those who had previously been diagnosed with STI and had engaged in chemsex in the past year. Advice from healthcare professional was an important factor considered by those willing to join clinical trials. Younger, better educated MSM, and those with lower CD4 counts were more concerned about potential risk of AIDS and potential complications upon trial participation.Conclusions: MSM living with HIV, especially those sexually active, showed positive attitude towards functional cure and willingness to join related clinical trials despite low awareness. To enhance preparedness for HIV functional cure trials, community education, updated information and appropriate medical advice would be needed. Safety is a major concern for potential enrollees in HIV functional cure trials. [ABSTRACT FROM AUTHOR]

Summer-spring predominance of tuberculosis (TB) has been widely reported. The relative contributions of exogenous recent infection versus endogenous reactivation to such seasonality remains poorly understood. Monthly TB notifications data between 2005 and 2017 in Hong Kong involving 64,386 cases (41% aged ≥ 65; male-to-female ratio 1.74:1) were examined for the timing, amplitude, and predictability of variation of seasonality. The observed seasonal variabilities were correlated with demographics and clinical presentations, using wavelet analysis coupled with dynamic generalised linear regression models. Overall, TB notifications peaked annually in June and July. No significant annual seasonality was demonstrated for children aged ≤ 14 irrespective of gender. The strongest seasonality was detected in the elderly (≥ 65) among males, while seasonal pattern was more prominent in the middle-aged (45–64) and adults (30–44) among females. The stronger TB seasonality among older adults in Hong Kong suggested that the pattern has been contributed largely by reactivation diseases precipitated by defective immunity whereas seasonal variation of recent infection was uncommon. [ABSTRACT FROM AUTHOR]

Keywords: SARS-CoV-2; Omicron variants; superspreading events; transmission heterogeneity EN SARS-CoV-2 Omicron variants superspreading events transmission heterogeneity 1 3 3 09/21/22 20220801 NES 220801 Although COVID-19 transmission dynamics are often heterogeneous, that is, only a small fraction of cases can generate unusual large outbreaks (i.e. superspreading), little is known about the superspreading potential of Omicron variant. We assessed the superspreading potential of COVID-19 outbreak seeded by the Omicron variants, using two observed transmission chains in Hong Kong. [Extracted from the article]

Introduction: Both daily and on‐demand regimens have been proven effective for pre‐exposure prophylaxis (PrEP) against HIV in men who have sex with men (MSM). We aimed to compare the two regimens on their coverage of condomless anal intercourse (CLAI) in MSM. Methods: A randomized, controlled, open‐label, crossover trial was conducted in a teaching hospital in Hong Kong. Participants were sexually active HIV‐negative MSM aged 18 years or above with normal renal function and without chronic hepatitis B infection. Oral tenofovir disoproxil fumarate 300 mg/emtricitabine 200 mg (TDF/FTC) tablets were prescribed for PrEP. After a 2‐week lead‐in with daily TDF/FTC for treatment‐naïve MSM for tolerance assessment, participants were randomly assigned in a 1:1 ratio with a block size of four to either daily‐first or on‐demand‐first arm based on the IPERGAY study, for receiving PrEP for 16 weeks, then crossed‐over to the alternative regimen for another 16 weeks. The primary outcome was the proportion of days with PrEP‐covered CLAI by intention‐to‐treat analysis. The trial is registered with the CCRB Clinical Trials Registry, CUHK, CUHK_CCRB00606, and is closed to accrual. Results: Between 25 August 2018 and 23 March 2019, 119 eligible participants were assigned to daily‐first arm (n = 59) and on‐demand‐first arm (n = 60) with an 87% overall completion rate (n = 103). With 96% and 54% of days on PrEP during daily and on‐demand periods, respectively, the proportion of days with PrEP‐covered CLAI between two arms were not statistically different (92% vs. 92%, p = 0.93). About half (47%) were diagnosed with at least one episode of incident sexually transmitted infection. Mild and time‐limited adverse events, including diarrhoea, headache, nausea and dizziness, were reported in 37 (31%) and 10 (8%) during the daily and on‐demand periods, respectively. At the end of the study, a similar proportion favoured daily or on‐demand regimen. Conclusions: High prevention‐effective adherence, as reflected from the coverage of CLAI, was achievable by either daily or on‐demand PrEP among MSM, albeit a higher number of tablets taken for daily PrEP. As both regimens were well accepted, a flexible approach adopting either or both regimens with possible switching is warranted in order to suit individual health needs. [ABSTRACT FROM AUTHOR]

Background Liver injury in patients with coronavirus disease 2019 (COVID-19) is common and prognostic. Direct viral tropism of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) for angiotensin-converting enzyme 2 receptors in hepatocytes may be one of the mechanisms of liver injury. We aimed to determine the role of viral persistence of SARS-CoV-2, based on cycle threshold (Ct) value, in liver injury in COVID-19. Methods This was a territory-wide retrospective cohort study of all public hospitals in Hong Kong. Laboratory-confirmed COVID-19 was identified. Serial liver biochemistries and Ct values of SARS-CoV-2 RNA were analyzed. Results We identified 7622 COVID-19 patients (mean age, 47 years; 48.2% male) diagnosed from March 24 to January 1, 2021, who had serial liver biochemistries and Ct values. A total of 1363 (17.9%) COVID-19 patients had alanine transferase (ALT)/aspartate aminotransferase (AST) elevations with 2 temporal patterns—early (within first 14 days of symptom onset) and late (>14 days from symptom onset). COVID-19 patients with ALT/AST elevations had a lower Ct value at admission (23 vs 25; P <.001), day 5 (24 vs 26; P <.001), and day 20 (31 vs 32; P <.001) after admission, compared with those without ALT/AST elevations. COVID-19 patients with ALT/AST elevations had a longer duration from first positive to first negative reverse transcription polymerase chain reaction test for SARS-CoV-2 (13 vs 9 days; P <.001). ALT/AST elevation and presence of diabetes were independent risk factors of viral persistence. Conclusions Liver injury in COVID-19 is linked to a higher SARS-CoV-2 viral load during the early phase of infection, signifying a possible direct viral injury to the liver. Prolonged viral persistence of SARS-CoV-2 is associated with liver injury. [ABSTRACT FROM AUTHOR]

Background and Objectives: Blood safety hinges not just on the scientific rationale for deferral period but potential donors' compliance with the prevailing policy. This study aimed to investigate donors' awareness, attitudes and compliance with the two‐phased policy implementation of time‐limited deferral for men who have sex with men (MSM) in Hong Kong. Materials and Methods: Three rounds of questionnaire survey were conducted between July 2017 and June 2019 covering the periods of pre‐implementation (Round A), post‐implementation without and with pre‐donation questionnaire revision (Round B and C). Chi‐square test and multivariable regression analysis were performed. Results: Of 3085 donors recruited, 968, 1036 and 1081 completed the surveys in Round A, B and C, respectively. The non‐compliance rate of MSM remained stable at 0·6% (3/497), 0·4% (2/551) and 0·5% (3/587) among male donors in Round A, B and C, respectively. Two MSM donors from Round C complying with the prevailing policy were identified. About two‐thirds (60·7%) of respondents from Round B and C were unaware of the policy change. Overall, over 80% were either neutral or positive about the change. Conclusion: Our study showed a consistently low non‐compliance rate of MSM over the three periods. The generally high level of acceptance of time‐limited deferral among donors lends support to science‐based policy development to protect blood safety. The identification of compliant MSM donors suggests that the 12‐month deferral is effective and acceptable to MSM. With a deferral period far exceeding the window period, it is a step towards a more equitable policy. [ABSTRACT FROM AUTHOR]

Background: In high-income countries with a low HIV prevalence, primary care doctors are likely the first point of medical contact for people at high risk of HIV. One of the key factors for successful implementation of preventive measures is the cooperation of primary healthcare providers. Hong Kong's population mostly seek primary care in the private sectors. Our study evaluated the involvement of private primary healthcare providers in HIV prevention and care. Methods: A cross-sectional postal structured questionnaire was administered to 1102 private primary care doctors in Hong Kong in December 2017. Responses were received via postal mail, fax or online. Non-respondents received a phone-call reminder to complete the survey. Descriptive analyses were performed for all the question items. Chi-square test was used to assess the association between participants' level of involvement in HIV prevention and care and their demographics and medical practice characteristics. Results: The response rate was 17.9% (197/1102). Most of the respondents were Chinese (95%) and have obtained their primary medical qualifications in Hong Kong (72%). More than half of the doctors have practiced in the private sector for more than 20 years (54%). Six aspects were used to evaluate practices or involvements in HIV prevention or care: Most of the responding doctors had offered advice (61%) and/or HIV test (76%) to patients with high-risk behaviors. However, fewer doctors had diagnosed HIV (27%), provided care for HIV positive patients (21%), reported HIV cases (19%) or prescribed antiretrovirals (4%). Nine (4.5%) did not answer all six questions on their practices or involvements in HIV prevention or care. The remaining respondents were then categorized into no/low involvement group and high involvement group. Overall,71% had no/low involvement (133/188) compared to 29% who had high involvement (55/188). Factors associated with high involvement included being in the 50–59 age group (OR: 2.48, 95% CI: 1.12–5.5), and belonging to a large practice (OR: 3.16, 95% CI: 1.4–7.12). Conclusions: Overall, most private primary care doctors in Hong Kong have no or low involvement in HIV prevention and care. However, most were willing and experienced in providing general preventive services, such as HIV testing and advice. [ABSTRACT FROM AUTHOR]

The implementation of social distancing measures through legal regulations to contain an epidemiologic outbreak has received little research attention. We reviewed and synthesized data on epidemiology, mobility trends and enforcement activities in the first 5 months of the COVID-19 epidemic in Hong Kong to examine the effectiveness of the newly enacted social distancing regulations. Data collected showed reduced patronage of retail and recreational activities during the epidemic. The regulations' enforcement could be inferred from the increase in the number of inspections, verbal warnings given to operators of scheduled premises and to people in public gatherings, but which rarely led to prosecutions. In parallel, the number of reported COVID-19 cases became stabilized. Our analyses suggested that public compliance with social distancing regulations could be maintained through promotional efforts without enforcement by prosecution. The adverse impacts of prolonged social distancing on the economy and citizens' social and psychological well-being were, however, of concern. [ABSTRACT FROM AUTHOR]

• Influenza vaccination coverage was low and hesitancy was prevalent in nurses. • High vaccine hesitancy was distinguished by scepticism on vaccine safety. • Moderately hesitant nurses mistrusted recommendations and had affordability concern. • Vaccine-hesitant nurses could be targeted for intervention. Influenza vaccine hesitancy among healthcare workers poses challenges to the achievement of herd immunity and causes infection risks to vulnerable patients. This study aimed to quantify the extent of influenza vaccine hesitancy among nurses in Hong Kong, to delineate its pattern, and to explore its socio-demographic, professional and personal correlates. Nurses in Hong Kong were recruited in a cross-sectional study involving the administration of an online questionnaire survey after the 2017/18 winter influenza season. Respondents' influenza vaccination behaviours, attitudes and psychological antecedents were assessed, followed by their delineation into subgroups along the hesitancy continuum through a combination of multiple correspondence analysis and K-means cluster analysis. Socio-demographic, professional and personal correlations of subgrouping were investigated using generalised ordered logistic regression. The overall vaccination coverage of nurses for the 2017/18 influenza season was 44%. Five clusters were differentiated by the level of influenza vaccine hesitancy: "Very high hesitancy-to-complete refusal" (n = 56; 7%) characterised by outright refusal of vaccination; "High hesitancy" (n = 171; 23%) distinguished by tendency of skipping vaccination and scepticism about safety of vaccine; "Moderate hesitancy" (n = 273; 36%) with uncertainties towards vaccination, mistrust of the government's vaccine recommendations and priority concern on affordability of vaccine; "Low hesitancy" (n = 95; 13%) with cautious acceptance towards vaccination and "No-to-minimal hesitancy" (n = 158; 21%) with strong vaccine confidence and compliance greatly linked to convenience of vaccine access. Nurses having completed at least 3 years' pre-registration professional training, having most family members vaccinated against influenza, and with influenza vaccination history during studentship were less vaccine hesitant. With more than half of the nurses in Hong Kong having moderate or higher level of influenza vaccine hesitancy, interventions customised to the needs of nurses as reflected from the characteristics of clusters along the vaccine hesitancy continuum could form an important strategy for improving vaccination uptake. [ABSTRACT FROM AUTHOR]

Introduction: Heterosexual infections have contributed to a high proportion of the HIV burden in Asia and Eastern Europe. Human mobility and non-local infections are important features in some cities/countries. An understanding of the determinants of the sustained growth of the heterosexual HIV epidemics would enable the potential impacts of treatment-based interventions to be assessed. Methods: We developed a compartmental model for heterosexual HIV transmissions, parameterized by clinical and surveillance data (1984–2014) in Hong Kong. HIV sequence data were included for examining genetic linkages and clustering pattern. We performed sensitivity analyses to evaluate effects of high-risk sexual partnership and proportions of non-locally acquired infections. Four hypothetical interventions (a) immediate treatment, (b) enhancement of retention in care, (c) HIV testing campaigns, and (d) test-and-treat strategy, were examined. Results: Data of 2174 patients (723 female and 1451 male) diagnosed with HIV between 1984 and 2012 in Hong Kong were collected for model parameterization. Among 1229 sequences of non-MSM (men who have sex with men) patients, 70% were isolates and 17% were either dyads or triads. In base-case scenario, the total estimated number of new infections in 2012–2023 would be 672 for male and 452 for female. Following 100% retention in care intervention, the total proportion of averted new infections in 2012–2023 would be 7% for male and 10% for female. HIV testing campaign in 2012 and 2017 followed by 100% immediate treatment strategy would avert 5% and 9% of male and female new infections, respectively. In the epidemic model, an increase of high-risk sexual partnership from 6% to 9% would increase the epidemic growth (annual number of newly diagnosed and newly infected cases) by about 10%. If no non-locally acquired infection occurred as from 2012, the epidemic growth would slump. To control the heterosexual epidemic, periodic HIV testing at 5-year intervals with immediate treatment would avert 5–13% of annual new infections in 2013–2023. Conclusions: Enhanced HIV testing with immediate treatment is most effective in controlling the heterosexual epidemic, the impacts of which might however be attenuated by any increase of non-locally acquired infection, assuming little variations of high risk partnership over time. [ABSTRACT FROM AUTHOR]

Background: Acute hepatitis C virus (HCV) infections have been increasingly reported among human immunodeficiency virus (HIV)‐positive men who have sex with men (MSM) in the Asia‐Pacific region. It remains unknown whether international network of HCV transmission has occurred in this region. Methods: HIV‐positive patients with acute HCV infection, defined as HCV seroconversion within a year or documented acute hepatitis with seroconversion, diagnosed in Hong Kong, Taipei and Tokyo during 2010‐2016 were included in this molecular epidemiology study. The NS5B region of the HCV genome (365 bp) was amplified using nested polymerase chain reaction and sequenced. Results: Of 234 HIV‐positive patients with acute HCV infection, all were male with 94% being MSM. At the diagnosis of acute HCV infection, 73.5% had concurrent sexually transmitted diseases and 88.0% were receiving combination antiretroviral therapy. The most prevalent HCV genotype was 3a, 2a and 1b in Hong Kong, Taipei and Tokyo respectively. Nine independent clusters belonging to five genotypes (1b, 2a, 2c, 3a and 6a) were identified, each of which occurred in one city without overlapping except for one 3a sequence from Taipei that was closely related genetically to the Hong Kong cluster. Conclusions: No international network of HCV transmission was identified among HIV–positive patients in the three Asia‐Pacific cities. The transmission dynamics of sexually acquired HCV differed by city, but the risk of intercity clustering should not be ignored. [ABSTRACT FROM AUTHOR]

Background: HIV spread in injecting drug users (IDU) occurs efficiently between individuals within their social networks. While methadone maintenance treatment has long known to be effective in combating HIV transmission in IDU, the impacts of one’s social connections and HIV status have not been well characterised. A study was conducted with the objective of differentiating the pattern of treatment participation between HIV-positive and negative methadone users and to understand its association with social connections with peers. Methods: Attendance data in one calendar year were extracted from a territory-wide electronic clinical record database of over 8000 methadone users attending 19 clinics in Hong Kong, a city with a relatively low HIV prevalence in injecting drug users. A case-control design was used by matching HIV positive methadone users with HIV negative controls. A temporal-social co-occurrence approach was adopted to construct a social network. Multiple logistic regression and network-based analyses were conducted. Results: In 2016, a total of 8332 methadone users had attended a clinic at least once, giving 1694016 attendance records that were included in the study. Some 432 methadone, 54 of whom HIV positive, were included in the case-control analyses. Multivariable logistic regression model showed that HIV-positive status was associated with drug injection history (adjusted odds ratio [aOR] 2.28, 95% confidence interval [95% CI] 1.19–4.38), not working fulltime (aOR 3.34, 95% CI 1.15–9.72), ethnic minority (aOR 2.59, 95% CI 1.33–5.02) and minimum daily dose of at least 20mg (aOR 3.64, 95% CI 1.08–12.26). Those having connections with other peers were older (aOR 1.02, 95% CI 1.00–1.04), had a higher mode dose (aOR 1.03, 95% CI 1.02–1.04) and had been admitted to methadone programme for longer time (aOR 1.07, 95% CI 1.02–1.13). Among those with connections, HIV-negative users did not have more connections (median degree centrality 21.00 vs 34.50, p = 0.26) but the network structure was stronger (clustering coefficient 0.65 vs 0.53, p = 0.03). Conclusion: The weak and sparse linkages may explain the generally low HIV prevalence and incidence in opioid-dependent persons in Hong Kong. Social support could play a constructive role in harm reduction and ethnic minority community-based organisations could help and reinforce treatment adherence. [ABSTRACT FROM AUTHOR]

HIV testing is the gateway to biomedical means of prevention and treatment. Identifying predictors of HIV testing is important to inform future preventive interventions. Of 444 men who have sex with men without known HIV infection enrolled in a study in Hong Kong, 64% had ever been HIV-tested. Testers were generally older, better educated, had a higher monthly income, and more likely self-identified as gay. Testers often used Internet and frequented saunas for sex networking, compared with non-testers attending bars, massage centres and public toilets. HIV testing habit also varied with the profile of body image type and preferred type in sex networking. Higher acceptance of pre-exposure prophylaxis (PrEP) was observed among testers. Overall, socioeconomic status played an important role in both HIV testing and access to PrEP. Interventions targeting sex networking venues and alternative means of testing provision are needed to increase coverage of HIV testing. [ABSTRACT FROM AUTHOR]

Background: To date, most studies on deferral of blood donors have focused on men who have sex with men (MSM) and/or injecting drug users. Few have examined deferrable risk behaviors relating to transfusion-transmissible infections (TTIs) in general. This study aimed to examine the prevalence of, and factors associated with, nondisclosure of TTI-related risk behaviors in donors.Study Design and Methods: Chinese-speaking donors who had just given blood in Hong Kong were invited to self-complete an anonymous questionnaire. Practices of one or more of seven deferrable risk behaviors associated with TTI were inquired. Factors associated with noncompliance with self-disclosure were evaluated by logistic regression.Results: Over a 4-week study period in 2012, a total of 1143 donors were recruited. Overall, 0.2% gave a history of drug injection, 1.7% had had sex with sex worker(s), and 0.3% had had sex with a human immunodeficiency virus-infected partner, while none had been paid for sex. Some 1.5% of male donors reported having same-sex behaviors. Factors associated with noncompliance were male gender (odds ratio [OR] 31.1; 95% confidence interval [CI], 3.7-263.6), having multiple sex partners (OR, 89.7; 95% CI, 28.7-279.9), and previous history of temporary deferral (OR, 11.4; 95% CI, 2.5-53.3). If suspected noncompliance was included, the overall prevalence of nondisclosure of deferrable behaviors could be high at 6.5%.Conclusion: Albeit uncommon, some donors fail to provide accurate answers to predonation screening questions and are not deferred appropriately. There is room for improvement to make deferral policy acceptable and understandable, so as to minimize the risk of TTI. Efforts are also needed to tackle the paucity of data on noncompliance of non-MSM donors. [ABSTRACT FROM AUTHOR]

Background: “Casual sex” is seldom as non-selective and random as it may sound. During each sexual encounter, people consciously and unconsciously seek their casual sex partners according to different attributes. Influential to a sexual network, research focusing on quantifying the effects of physical appearance on sexual network has been sparse. Methods: We evaluated the application of Log odds score (LOD) to assess the mixing patterns of 326 men who have sex with men (MSM) in Hong Kong in their networking of casual sex partners by Body Image Type (BIT). This involved an analysis of 1,196 respondents-casual sex partner pairs. Seven BITs were used in the study: Bear, Chubby, Slender, Lean toned, Muscular, Average and Other. Results: A hierarchical pattern was observed in the preference of MSM for casual sex partners by the latter's BIT. Overall, Muscular men were most preferred, followed by Lean toned while the least preferred was Slender, as illustrated by LOD going down along the hierarchy in the same direction. Marked avoidance was found between men who self-identified as Chubby and men of Other body type (within-group-LOD: 1.25–2.89; between-group-LOD: <−1). None of the respondents reported to have networked a man who self-identified as Average for casual sex. Conclusions: We have demonstrated the possibility of adopting a mathematical prototype to investigate the influence of BIT in a sexual network of MSM. Construction of matrix based on culture-specific BIT and cross-cultural comparisons would generate new knowledge on the mixing behaviors of MSM. [ABSTRACT FROM AUTHOR]

This study aims to assess potential environmental influences on allergy development in children. Based on a parent-completed questionnaire survey administered in Hong Kong in 2003 in accordance with the International Study of Asthma and Allergies in Childhood protocol, the prevalence and incidence of asthma and rhinoconjunctivitis of 508 preschool children aged 4 to 6 years in Yuen Long District were determined and a range of indoor and outdoor environmental factors were assessed. Exposure to moisture and mold in the first year of life increased the risk of asthma (adjusted odds ratio [aOR] = 2.56; 95% confidence interval [CI] = 1.40-4.68) and rhinoconjunctivitis (aOR = 2.09; 95% CI = 1.15-3.80). Current maternal smoking was also associated with a higher prevalence of asthma (aOR = 2.00; 95% CI = 1.04-3.84). No association was observed between outdoor traffic-related air pollutants and the prevalence of the allergic conditions. Indoor home environments had a stronger influence on allergy development, whereas exposure to traffic-related external environment gave a variable effect, the significance of which would be difficult to be substantiated. [ABSTRACT FROM PUBLISHER]

Seasonal influenza vaccination of nurses in Hong Kong fell from 57% in 2005 to 24% in 2012, paralleling concern for adverse reactions associated with vaccination. Decreased acceptance of vaccination was most prominent among nurses who had less work experience and more frequent contact with patients. [ABSTRACT FROM AUTHOR]

• Mycoplasma genitalium was detected in 8% of patients with non-gonococcal urethritis. • M. genitalium infection commonly occurred alone or in association with Chlamydia trachomatis infection. • Macrolide- and/or fluoroquinolone-resistance-associated mutations were common. • The M. genitalium resistance pattern varied within the Asia Pacific region and between continents. Mycoplasma genitalium is the cause of an emerging sexually transmitted infection (STI) with high propensity for development of antimicrobial resistance. In a prevalence study conducted at the public STI service in Hong Kong, the first void urine samples of 38 (8%) of 493 male patients with non-gonococcal urethritis (NGU) tested positive for M. genitalium using reverse transcription polymerase chain reaction. Patients with M. genitalium infection were younger [31 vs 33 years, odds ratio (OR) 0.96, 95% confidence interval (CI) 0.93–0.996; P =0.03], more likely to present with urethral discharge (12% vs 6%, OR 2.16, 95% CI 1.10–4.23; P =0.02) and had symptom duration >2 weeks (14% vs 6%, OR 2.34, 95% CI 1.10–4.97; P =0.03) compared with patients without M. genitalium infection. The prevalence of M. genitalium infection was lower in patients co-infected with Chlamydia trachomatis compared with patients with isolated infection (4% vs 10%, OR 0.38, 95% CI 0.17–0.84; P =0.02). The prevalence of M. genitalium infection was not higher in men who have sex with men. Antimicrobial-resistance-conferring mutations were present in 24 (63%) patients with M. genitalium – 23S rRNA 18 (47%) and parC 19 (53%). Similar to neighbouring countries in the Asia Pacific region, concurrent resistance mutations against both macrolides and fluoroquinolones were demonstrated in 14 (37%) patients. Histories of azithromycin and moxifloxacin use were significantly associated with a diagnosis of M. genitalium infection. Characteristically, NGU in Hong Kong featured the co-existence of mono-resistance against macrolides or fluoroquinolones, and the presence of dual class resistance. The geographic variability of antimicrobial resistance against M. genitalium is attributed not just to the different transmission networks formed in separate population groups, but the antimicrobial prescriptions for the treatment of urethritis in the community. [ABSTRACT FROM AUTHOR]

The article discusses a study to evaluate the early uptake of seasonal influenza vaccines by healthcare workers (HCWs) as well as their attitudes towards the vaccination following the incorporation of pandemic H1N1 (pH1N1) strain in the vaccines. Participants included nurses registered with any of three collaborating nursing associations in Hong Kong. The study found that poor coverage of vaccination among HCWs and varied and incorporation of the pH1N1 strain did not increase compliance.

Summary: Objectives: Human influenza A (H1N1) 2009 has caused severe epidemics in many countries, but its dynamics in spatial and temporal contexts have so far been poorly appreciated. Methods: A total of 24,414 laboratory confirmed human influenza A (H1N1) 2009 cases reported from May to September 2009 in Hong Kong were evaluated, using a Geographic Information System (GIS)-based approach. Spatio-temporal clustering was assessed after dividing Hong Kong into 4 geographic sectors, 18 districts and 500 m × 500 m cells. Global Moran’s I, Local Moran’s I and SaTScan™ were used in the exploration. Results: Spatio-temporal clusters first appeared on Hong Kong Island at week 3, alongside multiple foci suggestive of infection nidus introduced from abroad. The clusters grew rapidly and became confluent in urban areas, lasting till week 22. Separately, local clusters emerged in the North representing second or third generation infections, which died down over a relatively short period of time. Conclusion: Heterogeneity of spatio-temporal clustering of H1N1 was demonstrated during the epidemic, despite the small area of the territory of Hong Kong. The dynamics could have been shaped by population mobility at a local level. The application of GIS in epidemiology studies can add value to standard surveillance activities. [Copyright &y& Elsevier]

There have been limited studies on the potential role of methadone treatment in HIV prevention in Asia. Over an 8-week period, we assessed the profiles of drug-taking and HIV risk behaviors, and tried to identify their relationships with methadone adherence in 690 clients who attended Hong Kong''s methadone treatment program. In the preceding month, 71% of respondents reported using drugs and two-thirds of those respondents who had injected drugs at some time in their lives injected then. Infrequent clients who attended methadone clinics <2 times in the previous week were twice more likely to have injected drugs in the last month and six times more likely to have >5 injections in the last week than frequent clinic attendees. Also, clients taking <60 mg methadone daily were twice more likely to have >5 injections in the last week than those taking ≥60 mg methadone. The findings called for further studies on harm reduction programs for HIV prevention among drug users in Asian countries. [Copyright &y& Elsevier]

Summary: To effectively track the growth of influenza, we piloted an online system to monitor influenza-like illness (ILI) in the community in one district of Hong Kong. Four syndromic markers, namely fever, respiratory symptoms, fever with respiratory symptoms, fever and/or respiratory symptoms, either of the individual or of the household, were collected during the study period from June 2012 to October 2013. A total of 132 residents of Tuen Mun District reported syndromic markers at the individual and household levels on a weekly basis. Temporal patterns of these markers were compared with data derived from laboratory surveillance by dynamic linear regression. Household respiratory symptoms were found to be an effective syndromic marker, pre-dating overall laboratory virus surveillance results on influenza diseases in two influenza seasons by 3–4 weeks. To conclude, respiratory symptoms can be a good marker predicting the onset of the influenza season in the community, and is particularly useful with regard to data from households, even if the sample size may not be a large one. [ABSTRACT FROM AUTHOR]

Abstract: Background: In Hong Kong, methadone treatment is widely accessible. Injecting drug users (IDU) have a relatively low risk behavioural profile and low HIV prevalence (0.3%). The corresponding Hepatitis C (HCV) level, however, is unclear. Objectives: To determine the HCV prevalence in IDU in Hong Kong and to identify any associated factors. Study Design: A community-based HCV prevalence study of IDU was conducted in methadone clinics. Demographics and drug use pattern were collected through a questionnaire survey and blood samples were obtained for HCV serological tests. Results: Data of 567 IDU were analyzed. Most were male (84%) and ethnic Chinese (98%). The median age was 49 years and median injection duration 17 years. Two-thirds (62%) admitted ever sharing injecting equipments. Most (76%) reported having injection drug use in the preceding 3 months, and 44% abused midazolam/triazolam in addition to heroin. Prevalence of HCV antibodies was 85% (95% confidence interval 82.5–88.3%). Injection duration, recent injection, ever sharing injecting equipments and concomitant use of other drugs were independent factors associated with HCV infection. Conclusions: HCV prevalence is high in IDU despite a low HIV prevalence and widely available substitution treatment, which has probably slowed but not prevented the HCV epidemic in IDU in Hong Kong. [Copyright &y& Elsevier]

Despite being recommended by many medical organizations, the uptake rates of seasonal influenza vaccination among healthcare workers, including nurses, are still unsatisfactory. Considering the impact of cultural values on organizational behaviors, vaccination among nurses may also be influenced by cultural values via their impacts on socially oriented motivation and the acceptance of social influence. This study examined whether and in what way two individual-level cultural dimensions, collectivism and power distance, would influence vaccination via social benefits (i.e., self-and-clan protection and community protection) and social influence (i.e., authority advice, and family-and-peer advice), respectively, among nurses. A cross-sectional online survey. An invitation to participate in the survey was sent to nurses using the contact list of a professional nursing organization in Hong Kong and by personal referrals. A total of 1386 nurses (mean age = 37.82, SD = 10.36; 89% women) completed the survey. The survey included instruments on cultural values, perceived social benefits, and social influence, and questions regarding 2-year vaccination records. The mediation model was tested using structural equation modeling with bootstrapped samples. Subgroup analyses were conducted to examine whether the mediation paths were different across different levels of demographic factors. The structural paths in the mediation model were different between nurses that had been vaccinated in the past and those who had not. In the adoption model (i.e., for nurses non-vaccinated in the past), the positive effects of collectivism on vaccination were mediated by self-and-clan protection and authority advice, whereas the negative effect of collectivism on vaccination was mediated by community protection. In addition, the positive effect of power distance on vaccination was mediated by authority advice. In the maintenance model (i.e., for nurses vaccinated in the past), except for the positive effect of collectivism on vaccination via authority advice, the other indirect effects were not significant. The direct effect of collectivism on vaccination was negative, whereas the direct effect of power distance on vaccination was positive. Collectivism and power distance may guide how nurses attend to and process social information and subsequently influence their vaccination adoption behaviors. More research is needed to examine how cultural dimensions may influence vaccination maintenance and the applicability of the current findings to other cultures. [ABSTRACT FROM AUTHOR]

A tailored immunization program is deemed more successful in encouraging vaccination. Understanding the profiles of vaccine hesitancy constructs in nurses can help policymakers in devising such programs. Encouraging vaccination in nurses is an important step in building public confidence in the upcoming COVID-19 and influenza vaccination campaigns. Using a person-centered approach, this study aimed to reveal the profiles of the 5C psychological constructs of vaccine hesitancy (confidence, complacency, constraints, calculation, and collective responsibility) among Hong Kong nurses. Cross-sectional online survey. With the promotion of a professional nursing organization, we invited Hong Kong nurses to complete an online survey between mid-March and late April 2020 during the COVID-19 outbreak. 1,193 eligible nurses (mean age = 40.82, SD = 10.49; with 90.0% being female) were included in the analyses. In the online survey, we asked the invited nurses to report their demographics, COVID-19-related work demands (including the supply of personal protective equipment, work stress, and attitudes towards workplace infection control policies), the 5C vaccine hesitancy components, seasonal influenza vaccine uptake history, and the COVID-19 vaccine uptake intention. Latent profile analysis was employed to identify distinct vaccine hesitancy antecedent subgroups. Results revealed five profiles, including "believers" (31%; high confidence, collective responsibility; low complacency, constraint), "skeptics" (11%; opposite to the believers), "outsiders" (14%; low calculation, collective responsibility), "contradictors" (4%; high in all 5C constructs), and "middlers" (40%; middle in all 5C constructs). Believers were less educated, reported more long-term illnesses, greater work stress, higher perceived personal protective equipment sufficiency, and stronger trust in government than skeptics. They were older and had higher perceived personal protective equipment sufficiency than middlers. Also, believers were older and had greater work stress than outsiders. From the highest to the lowest on vaccination uptake and intention were believers and contradictors, then middlers and outsiders, and finally skeptics. Different immunization programs can be devised based on the vaccine hesitancy profiles and their predictors. Despite both profiles being low in vaccination uptake and intention, our results distinguished between outsiders and skeptics regarding their different levels of information-seeking engagement. The profile structure reveals the possibilities in devising tailored interventions based on their 5C characteristics. The current data could serve as the reference for the identification of individual profile membership and future profiling studies. Future endeavor is needed to examine the generalizability of the profile structure in other populations and across different study sites. Tweetable abstract : Covid-19 vaccine hesitancy profiles of Hong Kong nurses (believers, sceptics, outsiders, contradictors and middlers) highlight the importance of tailored vaccine campaigns. [ABSTRACT FROM AUTHOR]

A healthy healthcare system requires healthy healthcare workers. Protecting healthcare workers including nurses against COVID-19 is crucial, and vaccination could be a viable future option. However, vaccine hesitancy remains a global challenge. Nurses, as a trustworthy and creditable source of vaccine-related information, may build public confidence in vaccination. Hence, research on vaccine hesitancy among nurses is warranted. This study estimated nurses' influenza vaccination behaviors and intention to receive COVID-19 vaccine when available, and examined their corresponding 5C psychological antecedents (confidence, complacency, constraints, calculation, and collective responsibility). To investigate the impact of COVID-19-related work demands, the mediation effects of work stress on the association between work demands and COVID-19 vaccination intention were also examined. Cross-sectional online survey Nurses were invited to participate via the promotion of a professional nursing organization and by personal referrals during the COVID-19 outbreak in Hong Kong between mid-March and late April 2020. 1,205 eligible nurses (mean age = 40.79, SD = 10.47; 90% being female) were included in the analyses. Demographics, influenza vaccination, intention to have COVID-19 vaccine, the 5C vaccine hesitancy components, work stress and COVID-19-related work demands (insufficient supply of personal protective equipment, involvement in isolation rooms, and unfavorable attitudes towards workplace infection control policies) were reported in the survey. The influenza vaccine uptake rate and the proportion intending to take COVID-19 vaccine were 49% and 63%, respectively. Influenza vaccination was associated with working in public hospitals and all 5C constructs (more confidence, more collective responsibility and less complacency, constraints, and calculation), whereas stronger COVID-19 vaccination intention was associated with younger age, more confidence, less complacency and more collective responsibility. COVID-19-related demands were associated with greater work stress, and hence stronger COVID-19 vaccination intention. The potential uptake rate of COVID-19 vaccine among nurses was suboptimal to achieve herd immunity. The 5C constructs were useful in predicting influenza vaccination and, to a lesser extent, the intention to take COVID-19 vaccine. The uncertain attributes such as effectiveness, side effects, and effective duration of the COVID-19 vaccine may contribute to this discrepancy. With less work stress among nurses in the post-pandemic period, the intention to take COVID-19 vaccine will likely drop. The 5C constructs should be infused in vaccination campaigns. While a COVID-19 vaccine could be ready soon, the nursing profession may not be ready to accept it. More research work is needed to boost the uptake rate. Less than two-third of nurses intended to take COVID-19 vaccine when available. While a COVID-19 vaccine could be ready soon, nursing profession is not ready to accept it. [ABSTRACT FROM AUTHOR]

Understanding the driving forces of HIV infection is crucial for developing intervention strategies. We aimed to infer these forces from genetic linkages between past and newly diagnosed cases by a molecular approach. We recruited newly diagnosed HIV patients from all three HIV specialist clinics in Hong Kong, China, between 2016 and 2018 to collect their HIV sequences with corresponding behavioural and clinical data. We retrieved archived HIV sequences from 1994 to 2012 separately. We pooled and analysed sequences by constructing a network with 1·5% TN93 distance threshold and measured node degree centrality. We did univariate analyses to identify factors associated with genetic links with archived sequences among newly diagnosed patients, and used a generalised linear model to differentiate archived sequences having links with new cases adjusting for diagnosis year. 2778 partial pol sequences were amalgamated for network construction, of which 426 were newly diagnosed. The network contained 1908 (69%) nodes and 23 305 edges. Some 703 (3%) edges linked 192 archived samples with 135 new cases. Of 239 newly diagnosed patients with genetic connections, those linked with past infections were more likely to be subtype B (odds ratio 3·31; p<0·0001) and be 30 years or younger (2·26; p=0·0065). Men who have sex with men (MSM) linked with past infections were less likely to be engaged in chemsex (0·52; p=0·039) or users of a mainland Chinese gay dating mobile application (0·39; p=0·035). Generalised linear model showed that people with past infections linked to new cases were younger (p=0·0002), had a higher degree centrality (p<0·0001), were less likely to be subtype CRF01_AE (p=0·0019), and infected through heterosexual contact (p<0·0001) or injection drug use (p=0·0002) compared with MSM contact. HIV transmission chains linking new with past infections in Hong Kong were driven by younger MSM. Chemsex, emergence in recent years, only clustered in and contributed to some new infections. Formation of transmission linkages over time signified the importance of targeting new and established infections in developing prevention strategies. Research Grants Council of Hong Kong (14103315) and AIDS Trust Fund (MSS 229 R and 243 R). [ABSTRACT FROM AUTHOR]