The realization of the concept of Harm Reduction in Russia

By the present moment cases of HIV infection among injecting narcotic users (INU) have been registered in more than 100 countries. To prevent HIV infection, the program "Harm Reduction" has been developed in Britain; the program states that the prevention of HIV infection must be considered more important than the prevention of the use of narcotic drugs, as this infection is a growing danger for both drug users and public health in general. Breaking drug dependence must not be the only aim of services working with drug addicts, because this will exclude persons decisively disposed to the mode of life including the prolonged use of drugs from the sphere of their activity. Active INU having no contacts with organizations which must give them treatment and assistance find themselves in dangerous situations more often than INU maintaining contacts with such organizations. Penetration into such hidden group and its education must be the primary task. Propaganda plays a decisive role in this process, as the only way to penetrate into such group is to develop work in its territory, so that drug addicts, supplied with the necessary means could change their behavior in the desired direction. In the Russian Federation work on the project "Harm Reduction" has been carried out in 50 regions. This work has contributed to conducting teaching seminars, working out teaching programs, as well as to augmenting the interest among specialists of different professions to the problem of decreasing the spread of HIV infection. The importance of information distributed by the narcological service and the probability that very responsible persons take correct decisions on the basis of their understanding the situation have increased. The rating of public organization has risen.     

Stigma and Human Rights Abuses against People Who Inject Drugs in Russia—A Qualitative Investigation to Inform Policy and Public Health Strategies

Introduction

Drug policing practices in the Russian Federation (Russia) are often punitive and have been shown to be associated with HIV risk behaviors among people who inject drugs (PWID). Less is known about strategies to address the problem in that setting, where substance use stigma is highly persistent. A better understanding of forms, causes and consequences of drug policing in Russia could inform drug policy in a context of substantial policy resistance. This qualitative study’s goal is to characterize the phenomenon of police involvement with Russian PWID and to explore strategies for drug policing in the Russian country context.

Methods

Using a semi-structured interview guide, we collected data from a purposive sample of 23 key informants including PWID, police officers, and experts from civil society and international organizations in Russia. We used a thematic analysis approach to inductively generate new insight into the phenomenon of police involvement and potential strategies to address it.

Results

Policing practices involving PWID include unjustified arrests, planting of false evidence and extrajudicial syringe confiscations, and often constitute human rights violations. Russian PWID personally experienced police violence as ubiquitous, taking on various forms such as beating, unjustified arrests, verbal harassment, and coercion. The persistent societal stigma dehumanizes PWID, and such stigmatization facilitates police abuse. To address stigma and overcome the PWID-police adversity, study participants suggested fostering a mutual understanding between the police and public health sectors.

Conclusions

Participants describe substantial human rights violations as part of policing illicit drug use in Russia. Police should include principles of effective prevention of substance use and HIV risk reduction in their trainings. Alignment of public safety and public health goals could address drug use-related risks and HIV prevention among key populations in Russia.     

The role of public organizations in the prevention of HIV infection in Russia

The problem of the role of public organizations in the prevention of the spread of HIV infection in Russia is discussed. The correctly chosen strategy of cooperation between governmental structures and non-governmental public associations corresponds to the modern principles of state policy of enhancing the interest of the population in the problems of public health. Relationships built on the principles of mutual respect and partnership in the common work on the prevention of the spread of HIV infection in Russia must increase its effectiveness.     

A decrease in harm: a new concept for Russian public health

The main principles of the concept of the "decrease of harm", realized in many countries of the world, are presented and the expediency of using this concept in Russia is substantiated. The beginning of the realization of the Project "Decrease of Harm: the Russian Federation", aimed at training specialists capable of carrying out prophylactic work among users of intravenous drugs (UID), is demonstrated. The principles of the selection of the groups of trainees are shown: the groups are made up of physicians working at AIDS centres, specialists in narcology and representatives of non-governmental organizations. The course of training provides the basic information on the strategy of the prophylaxis of HIV infection among UID, including evaluation and study, outreach, change of syringes and needles, replacement therapy, the program of the treatment of drug addiction. At the present moment 46 specialists from 18 regions of Russia are taking the course of training.     

Health situation in former communist bloc is dire, says Unicef

The UN International Children's Emergency Fund (UNICEF) disclosed the dreadful health situation in the former Soviet Bloc. According to the report, "After the Fall: The Human Impact of Ten Years Transition," women and children in the former communist republic have suffered hard from both economic and social problems. Findings on health are particularly upsetting, especially with the re-emergence of the virtually eliminated "poverty diseases" such as diphtheria, poliomyelitis, tuberculosis, and sexually transmitted diseases (STDs) including HIV infection. Cases of diphtheria in Russia and Ukraine increased to 43,000 in 1998 from 1900 in 1990. Western parts of the former Soviet Union are now suffering from the reappearance of tuberculosis (10% affecting children), syphilis (221 cases per 100,000 population), and STDs, while HIV infection rates were as high as 270,000 by the end of 1998. On the other hand, economic depression has given rise to increasing drug misuse, alcoholism, injury, and suicide among the young population. Patrick McCormick, a spokesperson of the UNICEF Research Center in Florence, which published the report, said "there is freedom now, but the children are paying high for that freedom and they are not in the position to benefit from it".     

HIV/AIDS,Food Supplementation and Livelihood Programs in Uganda: A Way Forward?

Background

Over the last decade, health, nutrition and policy experts have become increasingly aware of the many ways in which food insecurity and HIV infection negatively impact and reinforce one another. In response, many organizations providing HIV care began supplying food aid to clients in need. Food supplementation, however, was quickly recognized as an unsustainable and incomplete intervention. Many HIV care organizations therefore developed integrated HIV and livelihood programs (IHLPs) to target the root causes of food insecurity.

Methods and Findings

We conducted a qualitative study using in-depth interviews with 21 key informants who worked at seven organizations providing HIV care, food aid, or IHLPs in Kampala, Uganda in 2007-2008 to better understand the impact of IHLPs on the well-being of people living with HIV and AIDS (PLWHAs) and the challenges in transitioning clients from food aid to IHLPs. There was strong consensus among those interviewed that IHLPs are an important intervention in addressing food insecurity and its adverse health consequences among PLWHAs. Key informants identified three main challenges in transitioning PLWHAs from food supplementation programs to IHLPs: (1) lack of resources (2) timing of the transition and (3) logistical considerations including geography and weather. Factors seen as contributing to the success of programs included: (1) close involvement of community leaders (2) close ties with local and national government (3) diversification of IHLP activities and (4) close integration with food supplementation programs, all linked through a central program of HIV care.

Conclusion

Health, policy and development experts should continue to strengthen IHLPs for participants in need. Further research is needed to determine when and how participants should be transitioned from food supplementation to IHLPs, and to determine how to better correlate measures of food insecurity with objective clinical outcomes so as to better evaluate program results.     

Prevalence of HIV Infection and Associated Risk Factors among Men Who Have Sex with Men (MSM) in Harbin,P. R. China

Objective

To assess the prevalence of HIV infection and characteristically risk of factors which associated with HIV infection among MSM in Harbin, China.

Methods

A face-to-face questionnaire interview was conducted among 463 Men Who Have Sex with Men (MSM) who were recruited by the snowball sampling in Harbin from April, 2011 to July, 2011. The questionnaire mainly included demographics, AIDS knowledge, homosexual behavior and the status of intervention in MSM. Blood specimens were obtained and tested for the diagnoses of HIV, syphilis and hepatitis C virus (HCV). Associations between above exposed factors and HIV infection were analyzed using a univariate analysis and forward stepwise logistic regression.

Results

The prevalence of HIV and syphilis was 9.5 and 14.3%. The awareness rate of AIDS was 86.8%. The rate of unprotected sexual behavior was 57.6% of MSM during the past 6 months. The univariate analysis identified that the age (age≥35 years old), cohabitation, more than 10 years of homosexual behavior and more than 10 homosexual partners were risk factors which associated with the HIV infection, and that protected sex during the past 6 months was a protective factor for the HIV infection. The multivariate analysis identified that the duration of homosexual behavior and commercial sexual behavior were independent risk factors which associated with the HIV infection, and the protected sex during the past 6 months was a protective factor for the HIV infection.

Conclusion

The prevalence of HIV among MSM in Harbin has been rapidly increasing in the past few years. Targeted, tailored, and comprehensive interventions are urgently needed to prevent the HIV infection from MSM.     

HIV infection in Russia and Commonwealth of Independent States: current situation and prospective

The dynamics of the spread of HIV infection in Russia and the CIS countries is presented. The relationship between the spread of HIV infection and an increase in the number of injection drug users is substantiated. The factors inhibiting the spread of the epidemic of HIV/AIDS in Russia and the CIS countries are analyzed with due regard to the world experience. Attention is paid to the development of the epidemic situation in HIV infection due to, similarly to Russia and to more than 100 countries of the world, drug addiction. The effectiveness of the activity of the Russian health service organs in controlling this epidemic is emphasized. The prospects of prophylactic measures for controlling HIV infection in Russia and the CIS countries are determined.     

Are HIV Epidemics among Men Who Have Sex with Men Emerging in the Middle East and North Africa?: A Systematic Review and Data Synthesis

Background

Men who have sex with men (MSM) bear a disproportionately higher burden of HIV infection than the general population. MSM in the Middle East and North Africa (MENA) are a largely hidden population because of a prevailing stigma towards this type of sexual behavior, thereby limiting the ability to assess infection transmission patterns among them. It is widely perceived that data are virtually nonexistent on MSM and HIV in this region. The objective of this review was to delineate, for the first time, the evidence on the epidemiology of HIV among MSM in MENA.

Methods and Findings

This was a systematic review of all biological, behavioral, and other related data on HIV and MSM in MENA. Sources of data included PubMed (Medline), international organizations'' reports and databases, country-level reports and databases including governmental and nongovernmental organization publications, and various other institutional documents. This review showed that onsiderable data are available on MSM and HIV in MENA. While HIV prevalence continues at low levels among different MSM groups, HIV epidemics appear to be emerging in at least few countries, with a prevalence reaching up to 28% among certain MSM groups. By 2008, the contribution of MSM transmission to the total HIV notified cases increased and exceeded 25% in several countries. The high levels of risk behavior (4–14 partners on average in the last six months among different MSM populations) and of biomarkers of risks (such as herpes simplex virus type 2 at 3%–54%), the overall low rate of consistent condom use (generally below 25%), the relative frequency of male sex work (20%–76%), and the substantial overlap with heterosexual risk behavior and injecting drug use suggest potential for further spread.

Conclusions

This systematic review and data synthesis indicate that HIV epidemics appear to be emerging among MSM in at least a few MENA countries and could already be in a concentrated state among several MSM groups. There is an urgent need to expand HIV surveillance and access to HIV testing, prevention, and treatment services in a rapidly narrowing window of opportunity to prevent the worst of HIV transmission among MSM in the Middle East and North Africa. Please see later in the article for the Editors'' Summary     

Cost-effectiveness of HIV screening in STD clinics, emergency departments, and inpatient units: a model-based analysis

Background

Identifying and treating persons with human immunodeficiency virus (HIV) infection early in their disease stage is considered an effective means of reducing the impact of the disease. We compared the cost-effectiveness of HIV screening in three settings, sexually transmitted disease (STD) clinics serving men who have sex with men, hospital emergency departments (EDs), settings where patients are likely to be diagnosed early, and inpatient diagnosis based on clinical manifestations.

Methods and Findings

We developed the Progression and Transmission of HIV/AIDS model, a health state transition model that tracks index patients and their infected partners from HIV infection to death. We used program characteristics for each setting to compare the incremental cost per quality-adjusted life year gained from early versus late diagnosis and treatment. We ran the model for 10,000 index patients for each setting, examining alternative scenarios, excluding and including transmission to partners, and assuming HAART was initiated at a CD4 count of either 350 or 500 cells/µL. Screening in STD clinics and EDs was cost-effective compared with diagnosing inpatients, even when including only the benefits to the index patients. Screening patients in STD clinics, who have less-advanced disease, was cost-effective compared with ED screening when treatment with HAART was initiated at a CD4 count of 500 cells/µL. When the benefits of reduced transmission to partners from early diagnosis were included, screening in settings with less-advanced disease stages was cost-saving compared with screening later in the course of infection. The study was limited by a small number of observations on CD4 count at diagnosis and by including transmission only to first generation partners of the index patients.

Conclusions

HIV prevention efforts can be advanced by screening in settings where patients present with less-advanced stages of HIV infection and by initiating treatment with HAART earlier in the course of infection.     

Understanding HIV Risk Behavior among Tuberculosis Patients with Alcohol Use Disorders in Tomsk,Russian Federation

Russian Federation’s (RF) HIV epidemic is the fastest growing of any country. This study explores factors associated with high HIV risk behavior in tuberculosis (TB) patients with alcohol use disorders in Tomsk, RF. This analysis was nested within the Integrated Management of Physician-delivered Alcohol Care for TB Patients (IMPACT, trial number {"type":"clinical-trial","attrs":{"text":"NCT00675961","term_id":"NCT00675961"}}NCT00675961) randomized controlled study of integrating alcohol treatment into TB treatment in Tomsk. Demographics, HIV risk behavior (defined as participant report of high-risk intravenous drug use and/or multiple sexual partners with inconsistent condom use in the last six months), clinical data, alcohol use, depression and psychosocial factors were collected from 196 participants (161 male and 35 female) at baseline. Forty-six participants (23.5%) endorsed HIV risk behavior at baseline. Incarceration history(Odds Ratio (OR)3.93, 95% confidence interval (CI) 1.95, 7.95), age under 41 (OR:2.97, CI:1.46, 6.04), drug addiction(OR: 3.60 CI:1.10, 11.77), history of a sexually transmitted disease(STD)(OR 2.00 CI:1.02, 3.90), low social capital (OR:2.81 CI:0.99, 8.03) and heavier alcohol use (OR:2.56 CI: 1.02, 6.46) were significantly more likely to be associated with HIV risk behavior at baseline. In adjusted analysis, age under 41(OR: 4.93, CI: 2.10, 11.58), incarceration history(OR: 3.56 CI:1.55, 8.17) and STD history (OR: 3.48, CI: 1.5, 8.10) continued to be significantly associated with HIV risk behavior. Understanding HIV transmission dynamics in Russia remains an urgent priority to inform strategies to address the epidemic. Larger studies addressing sex differences in risks and barriers to protective behavior are needed.     

Disassortative Age-Mixing Does Not Explain Differences in HIV Prevalence between Young White and Black MSM: Findings from Four Studies

Objective

Age disassortativity is one hypothesis for HIV disparities between Black and White MSM. We examined differences in age mixing by race and the effect of partner age difference on the association between race and HIV status.

Design

We used data from four studies of MSM. Participants reported information about recent sexual partners, including age, race, and sexual behavior. Two studies were online with a US sample and two focused on MSM in Atlanta.

Methods

We computed concordance correlation coefficients (CCCs) by race across strata of partner type, participant HIV status, condom use, and number of partners. We used Wilcoxon rank-sum tests to compare Black and White MSM on partner age differences across five age groups. Finally, we used logistic regression models using race, age, and partner age difference to determine the odds ratio of HIV-positive serostatus.

Results

Of 48 CCC comparisons, Black MSM were more age-disassortative than White MSM in only two. Furthermore, of 20 comparisons of median partner age, Black and White MSM differed in two age groups. One indicated larger age gaps among the Black MSM (18-19). Prevalent HIV infection was associated with race and age. Including partner age difference in the model resulted in a 2% change in the relative odds of infection among Black MSM.

Conclusions

Partner age disassortativity and partner age differences do not differ by race. Partner age difference offers little predictive value in understanding prevalent HIV infection among Black and White MSM, including diagnosis of HIV-positive status among self-reported HIV-negative individuals.     

Prevalence and Correlates of HIV Infection among Street Boys in Kisumu,Kenya

Introduction

Despite their perceived vulnerability to HIV, East African street youth have been neglected in HIV prevention research. We examined HIV seroprevalence and correlates of HIV infection in a sample of male street youth in Kisumu, Kenya.

Methods

We enrolled a street-recruited sample of 13–21 year old street youth. Participants completed a survey followed by voluntary HIV counseling and testing. Survey items included demographics, homelessness history, survival activities, sexual behavior and substance use. We examined the relationship between predictor variables, markers of coercion and marginalization and HIV.

Results

The sample included 296 males. Survival activities included garbage picking (55%), helping market vendors (55%), begging (17%), and working as porters (46%) or domestic workers (4%). Forty-nine percent of participants reported at least weekly use of alcohol and 32% marijuana. Forty-six percent of participants reported lifetime inhalation of glue and 8% fuel. Seventy-nine percent of participants reported lifetime vaginal sex, 6% reported lifetime insertive anal sex and 8% reported lifetime receptive anal sex. Twelve (4.1%; 95% CI: 2.3–7.0) participants tested positive for HIV. Of those, all had been on the street for at least one year and all had engaged in vaginal sex. Occupations placing youth at particular risk of coercion by adults, including helping market vendors (prevalence ratio (PR) = 8.8; 95% CI: 1.2–67.5) and working as domestic workers (PR = 4.6; 95% CI: 1.1–19.0), were associated with HIV infection. Both insertive anal sex (PR = 10.2; 95% CI: 3.6–29.4) and receptive anal sex (PR = 3.9; 95% CI: 1.1–13.4) were associated with HIV infection. Drug use, begging, and garbage picking were not associated with HIV infection.

Conclusions

Although HIV prevalence in our sample of street youth is comparable to that of similarly-aged male youth in Nyanza Province, our findings highlight behavioral factors associated with HIV infection that offer opportunities for targeted prevention among street youth in East Africa.     

A model of enhancement and inhibition of HIV infection of monocytes by antibodies against HIV

Antibodies (Ab) specific for epitopes on HIV glycoprotein gp120 or gp41 can inhibit or enhance HIV infection of human cellsin vitro. These effects may have significant implications both for the pathogenesis of chronic HIV infection and for vaccine development. A particularly puzzling findingin vitro is antibody dependent enhancement (ADE) at low concentrations of Ab while high concentrations of the same antibody inhibit infection. Similar phenomena have been observed for other enveloped viruses. Antibodies can inhibit infection by several mechanisms. However, by binding to receptors on target cells, virus bound antibodies can also enhance adhesion to these cells and thereby facilitate infection. We propose a mathematical model that describes how these two processes interact and hereby provide an explanation for the observed enhancement/neutralization phenomena. Simulation results were validated with good agreement against empirical data from antibody dependent enhancement of HIV infection of monocytoid (U937) cellsin vitro, and the model should be applicable to otherin vitro systems involving different cells and viruses.The model indicates that for the common type of HIV neutralizing antibody, acting at a post-CD4-binding step, there is a neutralizing window defined by the affinity and concentration of antibody.     

Cost Effectiveness of Screening Strategies for Early Identification of HIV and HCV Infection in Injection Drug Users

Objective

To estimate the cost, effectiveness, and cost effectiveness of HIV and HCV screening of injection drug users (IDUs) in opioid replacement therapy (ORT).

Design

Dynamic compartmental model of HIV and HCV in a population of IDUs and non-IDUs for a representative U.S. urban center with 2.5 million adults (age 15–59).

Methods

We considered strategies of screening individuals in ORT for HIV, HCV, or both infections by antibody or antibody and viral RNA testing. We evaluated one-time and repeat screening at intervals from annually to once every 3 months. We calculated the number of HIV and HCV infections, quality-adjusted life years (QALYs), costs, and incremental cost-effectiveness ratios (ICERs).

Results

Adding HIV and HCV viral RNA testing to antibody testing averts 14.8–30.3 HIV and 3.7–7.7 HCV infections in a screened population of 26,100 IDUs entering ORT over 20 years, depending on screening frequency. Screening for HIV antibodies every 6 months costs $30,700/QALY gained. Screening for HIV antibodies and viral RNA every 6 months has an ICER of $65,900/QALY gained. Strategies including HCV testing have ICERs exceeding $100,000/QALY gained unless awareness of HCV-infection status results in a substantial reduction in needle-sharing behavior.

Discussion

Although annual screening for antibodies to HIV and HCV is modestly cost effective compared to no screening, more frequent screening for HIV provides additional benefit at less cost. Screening individuals in ORT every 3–6 months for HIV infection using both antibody and viral RNA technologies and initiating ART for acute HIV infection appears cost effective.     

Mathematical Analysis of the Transmission Dynamics of HIV Syphilis Co-infection in the Presence of Treatment for Syphilis

The re-emergence of syphilis has become a global public health issue, and more persons are getting infected, especially in developing countries. This has also led to an increase in the incidence of human immunodeficiency virus (HIV) infections as some studies have shown in the recent decade. This paper investigates the synergistic interaction between HIV and syphilis using a mathematical model that assesses the impact of syphilis treatment on the dynamics of syphilis and HIV co-infection in a human population where HIV treatment is not readily available or accessible to HIV-infected individuals. In the absence of HIV, the syphilis-only model undergoes the phenomenon of backward bifurcation when the associated reproduction number (\({\mathcal {R}}_{T}\)) is less than unity, due to susceptibility to syphilis reinfection after recovery from a previous infection. The complete syphilis–HIV co-infection model also undergoes the phenomenon of backward bifurcation when the associated effective reproduction number (\({\mathcal {R}}_{C}\)) is less than unity for the same reason as the syphilis-only model. When susceptibility to syphilis reinfection after treatment is insignificant, the disease-free equilibrium of the syphilis-only model is shown to be globally asymptotically stable whenever the associated reproduction number (\({\mathcal {R}}_{T}\)) is less than unity. Sensitivity and uncertainty analysis show that the top three parameters that drive the syphilis infection (with respect to the associated response function, \({\mathcal {R}}_{T}\)) are the contact rate (\(\beta _S\)), modification parameter that accounts for the increased infectiousness of syphilis-infected individuals in the secondary stage of the infection (\(\theta _1\)) and treatment rate for syphilis-only infected individuals in the primary stage of the infection (\(r_1\)). The co-infection model was numerically simulated to investigate the impact of various treatment strategies for primary and secondary syphilis, in both singly and dually infected individuals, on the dynamics of the co-infection of syphilis and HIV. It is observed that if concerted effort is exerted in the treatment of primary and secondary syphilis (in both singly and dually infected individuals), especially with high treatment rates for primary syphilis, this will result in a reduction in the incidence of HIV (and its co-infection with syphilis) in the population.     

The Role of NGOs in HIV/AIDS Prevention in Nigeria

The HIV/AIDS pandemic data in Nigeria indicates that 3.5 million Nigerians have HIV/AIDS. The Obasanjo administrations National Action Committee on AIDS is uncoordinated and lacks commitment as indicated by the shortage of antiretroviral drugs, corruption and administration of expired drugs. NGOs combating the spread of HIV in Nigeria attempt to reach many community groups, religious, womens, youth and mens organizations. The increased awareness about HIV/AIDS through promotion of public discourse has helped people to take positive action toward prevention of HIV infection.     

Risk of HIV infection from blood transfusion in Montreal

OBJECTIVES: To determine the incidence (including associated donor characteristics and time trends) of HIV infection among repeat blood donors and to estimate the risk of HIV transmission from blood transfusion in Montreal and in Canada as a whole. DESIGN: Retrospective cohort analysis. SETTING: Montreal Centre Blood Transfusion Service. PARTICIPANTS: People who donated blood at least twice after Nov. 1, 1985, and at least once from Apr. 1, 1989, to Mar. 31, 1993. INTERVENTION: Blood was screened for HIV by enzyme-linked immunosorbent assay and results were confirmed by Western blot analysis. OUTCOME MEASURES: Incidence density (the incidence rate per person-time) of HIV infection among repeat blood donors by sex, age group and region of residence, and incidence density and risk among first-time donors and for Canada as whole. RESULTS: There were 200,196 eligible donors and 432,631 person-years (PY) of observation. From 1989 to 1993, there were 18 HIV seroconversions among repeat donors. The crude incidence density was 3.3 per 100,000 PY (95% confidence interval [CI] 1.8 to 5.4 per 100,000 PY); it was 4.9 per 100,000 PY among men and 0.61 per 100,000 PY among women. Age-specific incidence per 100,000 PY was 2.5 among those 12-29 years of age, 5.1 among those 30-49, 2.9 among those 40-49, and 1.4 among those 50 and older. Based on an estimated mean "window period" (from when a donor''s blood is capable of transmitting HIV until detectable antibody appears) of 25 days, the current risk of HIV infection from repeat donors in the window period is estimated at 1 in 440,000. Inclusion of blood units from first-time donors produces an overall risk of 1 in 390,000 (95% CI 1 in 250,000 to 655,000). The estimated risk per blood unit in Canada as a whole is 1 in 913000 (95% CI 1 in 507,000 to 2,050,000). CONCLUSIONS: This "sentinel" population of repeat blood donors is subject to important trends in HIV spread. Therefore, estimating the incidence density of HIV infection in repeat donors provides insight into the epidemiologic characteristics of HIV infection at minimal expense. As a result of measures to improve blood safety, including HIV testing, the incidence of HIV infection among blood donors in Canada is low and the risk of HIV transmission from transfusion is extremely small, although not zero.     

A mathematical model of HIV dynamics in the presence of a rescuing virus with replication deficiency

Recently, an enzyme (Cre recombinase) has been developed by directed evolution that successfully removes the HIV genome from the nuclear DNA of infected cells. To explore this idea further, we hypothesized that a replication deficient virus (called “police virus”), added externally, can deliver such a recombinase which excises the integrated HIV DNA from the genome of infected cells. Such a “police virus” could attack and remove the integrated provirus which is not possible using contemporary strategies. The hypothesis was tested by developing a mathematical model that describes the dynamics of virus-host cell interaction and the consequences of introducing the “police virus”. The simulations show that such a therapeutic vector may eradicate all HIV viruses from the system in the long term. All components of the HIV infection (free virus, latently, and actively infected cells) can be cleared and the system ends up only with susceptible CD4+ cells. The proposed model may provide new insights in the dynamical behavior and future alternative treatments of HIV.