Do Peer Navigators Improve Initiation and Retention in HIV/VH/STI Treatment Programs for People From Key Populations? A Systematic Review of Effectiveness, Values and Preferences, and Cost

BACKGROUND

Key populations are disproportionately affected by HIV, viral hepatitis (VH), and sexually transmitted infections (STIs) and face barriers to care. Peer navigation programs are widely used, but evidence supporting their use has not been synthesized.

SETTING

Peer navigation programs for sex workers, men who have sex with men, people who inject drugs, prisoners, and trans and gender diverse people globally.

METHODS

To inform World Health Organization guidelines, we conducted a systematic review of effectiveness, values and preferences, and cost studies published between January 2010 and May 2021. We searched CINAHL, PsycINFO, PubMed, and EMBASE; screened abstracts; and extracted data in duplicate. The effectiveness review included randomized controlled trials and comparative observational studies evaluating time to diagnosis or linkage to care, treatment initiation, treatment retention/completion, viral load, cure, or mortality. We assessed risk of bias and summarized findings in GRADE evidence profiles. Values and preferences and cost data were summarized descriptively.

RESULTS

Four studies evaluated the effectiveness of peer navigators for key populations. All were focused on HIV; none were designed for VH or STIs. These studies showed mixed effects on linkage to care, treatment retention/completion, and viral load; no studies measured treatment initiation, cure, or mortality. Two values and preferences studies with community-based organization staff and health workers suggested peer navigators for key populations were acceptable and valued, although continued challenges remained. No cost studies were identified.

CONCLUSIONS

Although limited, available studies provide moderate certainty evidence for benefits of HIV/VH/STI peer navigation programs for key populations. Further evaluations are needed.

Unexpected and delayed fragmentation dynamics of the organometallic ferrocene induced by ion-collision

We have investigated the fragmentation dynamics of the organometallic ferrocene molecule after interaction with multiply charged ions using multicoincidence mass spectrometry and quantum chemistry calculations. We observed unexpected fragmentation dynamics of the two-body breakup channels from ferrocene dications revealing a charge screening effect from the iron atom and delayed fragmentation dynamics. These observations are rationalized through the population of a specific long-lived excited state, where one positive charge is located on each cyclopentadienyl ring.

Prevalence of hepatitis B and C virus infections in hemodialysis patients in Vietnam: A systematic review and meta-analysis

Background and Aim

Chronic hemodialysis patients are at high risk of contracting hepatitis B (HBV) and C (HCV) virus infections. In Vietnam, the seroprevalence of HBV and HCV infections is approximately 10 and 4%, respectively. Although the chronic hemodialysis population is increasing, relatively little epidemiology is available for HBV and HCV infections in this population. To address this, we reviewed the current literature on the magnitude of these infections in the hemodialysis population in Vietnam.

Methods

Four databases were used to search for publications containing the prevalence of HBV and/or HCV infections in hemodialysis patients in Vietnam. Grey literature search was utilized to identify local publications. Prevalence and 95% confidence interval were used or calculated, and a meta‐analysis was conducted on HBV and HCV prevalence for comparison.

Results

Sixteen studies were included in the review. The search identified knowledge gaps in the current literature. Available data show that HBV and HCV infections remain prevalent in the hemodialysis population. HBV prevalence is not different between the north and the south of Vietnam. The pattern of HCV prevalence is different, with recent reports of lower prevalence in the south than in the north, while HCV prevalence varies between hemodialysis units in the same regions.

Conclusions

A national prevalence survey of hemodialysis patients would improve the reliability and generalizability of the findings. However, the review confirmed that both HBV and HCV were prevalent in hemodialysis patients. The findings support a reinforcement of infection prevention to minimize the risk of HBV and HCV transmission in hemodialysis facilities.

A new lactam 28-norlimonoid from the leaves of Azadirachta indica A. Juss. (Meliaceae)

From an EtOAc-soluble fraction of the leaves of Azadirachta indica, one new lactam 28-norlimonoid named nimbandiolactam-21 (1), together with 2 known limonoids (2 and 3) were isolated. Their relative structures were elucidated based on NMR spectroscopic analysis. Nimbandiolactone-23 (2) showed the most potent α-glucosidase inhibitory activity, with an IC₅₀ value of 38.7 μM. Compound 1 represents the first naturally occurring example of a 28-norlimonoid having the lactam moiety. The plausible biosynthetic pathway for the formation of lactam moiety in 1 was proposed.

Derivatives of imidazotriazine and pyrrolotriazine C-nucleosides as potential new anti-HCV agents

Previous investigations identified 2'-C-Me-branched ribo-C-nucleoside adenosine analogues, 1, which contains a pyrrolo[2,1-f][1,2,4]triazin-4-amine heterocyclic base, and 2, which contains an imidazo[2,1-f][1,2,4]triazin-4-amine heterocyclic base as two compounds with promising anti-HCV in vitro activity. This Letter describes the synthesis and evaluation of a series of novel analogues of these compounds substituted at the 2-, 7-, and 8-positions of the heterocyclic bases. A number of active new HCV inhibitors were identified but most compounds also demonstrated unacceptable cytotoxicity. However, the 7-fluoro analogue of 1 displayed good potency with a promising cytotherapeutic margin.

Discovery and Synthesis of C-Nucleosides as Potential New Anti-HCV Agents

Nucleoside analogues have long been recognized as prospects for the discovery of direct acting antivirals (DAAs) to treat hepatitis C virus because they have generally exhibited cross-genotype activity and a high barrier to resistance. C-Nucleosides have the potential for improved metabolism and pharmacokinetic properties over their N-nucleoside counterparts due to the presence of a strong carbon-carbon glycosidic bond and a non-natural heterocyclic base. Three 2'CMe-C-adenosine analogues and two 2'CMe-guanosine analogues were synthesized and evaluated for their anti-HCV efficacy. The nucleotide triphosphates of four of these analogues were found to inhibit the NS5B polymerase, and adenosine analogue 1 was discovered to have excellent pharmacokinetic properties demonstrating the potential of this drug class.

Hepatitis B infection in Vietnam: current issues and future challenges

Hepatitis B virus (HBV) infection remains a major public health problem in Vietnam. Recent studies have found that prevalence of current HBV infection (HBsAg+) ranges from 10% to 20% in the general population and 20% to 40% among injecting drug users and HIV+ patients. However, HBV prevention and control in Vietnam relies heavily on universal infant vaccination program and HBsAg screening for blood donors. Currently, HBV prevention and control is underfunded by the government and receives little support from international agencies. HBV-related liver disease will continue to create a heavy burden for public health in Vietnam in the next several decades unless appropriate interventions are undertaken urgently. Establishment of a national strategy for HBV prevention and control is crucial to develop and implement effective interventions.

Hepatitis B-related hepatocellular carcinoma: epidemiological characteristics and disease burden

Worldwide, 350 million people are chronically infected with hepatitis B virus (HBV) who are at greater risk of hepatocellular carcinoma (HCC) compared with uninfected people. The relative risks of HCC among people infected with HBV ranges from 5 to 49 in case-control studies and from 7 to 98 in cohort studies. More than 50% of HCC cases worldwide and 70-80% of HCC cases in highly HBV endemic regions are attributable to HBV. Incidence of HCC (per 100,000 person/year) among people with chronic HBV infection ranges from 400 to 800 in male and from 120 to 180 in female. Factors associated with increased risk of HCC include demographic characteristics (male sex and older age), lifestyles (heavy alcohol consumption and smoking), viral factors (genotype C, D F, high level of HBV DNA, core/precore mutation) and clinical factors (cirrhosis, elevated alpha-fetoprotein (AFP) and alanine aminotransferase (ALT)). HBV-related HCC has extremely poor prognosis with median survival less than 16 months. Survival rates of HBV-related HCC ranged from 36% to 67% after 1 year and from 15% to 26% after 5 year of diagnosis. Older age, liver function impairment, vascular invasion, tumour aggressiveness and elevated AFP are associated with HCC survival. Global burden of HBV-related liver disease is still a major challenge for public health in the 21st century. While decreases in incidence of HBV infection have been observed in birth cohorts following the introduction of universal infant HBV vaccination programme, HBV-related HCC incidence in is projected to increase for at least two decades because of the high prevalence of chronic HBV infection and prolonged latency to HCC development. To reduce HBV-related HCC continued expansion of universal infant HBV vaccination is required along with antiviral therapy targeted to those individuals at highest risk of HCC. Broad public health strategies should include routine testing to identify chronic HBV infection, improved health infrastructures including human resource to provide diagnosis and treatment assessment.

Predictors and survival in hepatitis B-related hepatocellular carcinoma in New South Wales, Australia

BACKGROUND AND AIM

Incidence and mortality of hepatocellular carcinoma (HCC) has increased markedly over the last three decades in Australia. An increasing proportion of HCC cases is related to chronic viral hepatitis including hepatitis B virus (HBV) infection. However, there is very limited data on HBV-related HCC survival.

METHODS

Data on HBV-related HCC cases was obtained from a community-based linkage study. HCC cases notified to the New South Wales (NSW) Central Cancer Registry (CCR) during the period 1994-2002 were linked to HBV notifications from the NSW Health Department. Age, sex, country of birth, year of diagnosis, tumor stage were extracted from the CCR database. Survival analysis was conducted to determine median survival and identify predictors of survival.

RESULTS

Over the 9-year study period, 278 HCC cases were linked to chronic HBV infection. The majority of cases were male (83.5%) and overseas-born (93.6%); Asian-born cases accounted for 72.1%. Median survival following HCC diagnosis was 15.0 months. HCC survival was poorer among older age groups (P < 0.0001), and among cases with regional spread (hazard ratio, 3.23; 95% confidence interval, 1.83-5.69; P < 0.0001) and distant metastases (hazard ratio, 3.85; 95% confidence interval, 2.44-6.08; P < 0.0001). Sex, region of birth and study period (1994-1997 vs 1998-2002) were not associated with HCC survival.

CONCLUSION

The vast majority of HBV-related HCC were overseas-born, however, region of birth was unrelated to HCC survival. The continued extremely poor HCC survival, including lack of improvement in HCC survival in more recent years, suggests low uptake of HCC screening programs. Public health strategies including early diagnosis and appropriate referral for antiviral therapy assessment and increased HCC screening among high-risk populations are required to reduce HCC incidence and improve HCC survival.