Brazilian blood donation eligibility criteria for dermatologic patients

A focused and commented review on the impact of dermatologic diseases and interventions in the solidary act of donating blood is presented to dermatologists to better advise their patients. This is a review of current Brazilian technical regulations on hemotherapeutic procedures as determined by Ministerial Directive #1353/2011 by the Ministry of Health and current internal regulations of the Hemotherapy Center of Ribeirão Preto, a regional reference center in hemotherapeutic procedures. Criteria for permanent inaptitude: autoimmune diseases (>1 organ involved), personal history of cancer other than basal cell carcinoma, severe atopic dermatitis or psoriasis, pemphigus foliaceus, porphyrias, filariasis, leprosy, extra pulmonary tuberculosis or paracoccidioidomycosis, and previous use of etretinate. Drugs that impose temporary ineligibility: other systemic retinoids, systemic corticosteroids, 5-alpha-reductase inhibitors, vaccines, methotrexate, beta-blockers, minoxidil, anti-epileptic, and anti-psychotic drugs. Other conditions that impose temporary ineligibility: occupational accident with biologic material, piercing, tattoo, sexually transmitted diseases, herpes, and bacterial infections, among others. Discussion: Thalidomide is currently missing in the teratogenic drugs list. Although finasteride was previously considered a drug that imposed permanent inaptitude, according to its short halflife current restriction of 1 month is still too long. Dermatologists should be able to advise their patients about proper timing to donate blood, and discuss the impact of drug withdrawal on treatment outcomes and to respect the designated washout periods.

Transmission of Chlamydia trachomatis through sexual partnerships: a comparison between three individual-based models and empirical data

Chlamydia trachomatis is the most common bacterial sexually transmitted infection (STI) in many developed countries. The highest prevalence rates are found among young adults who have frequent partner change rates. Three published individual-based models have incorporated a detailed description of age-specific sexual behaviour in order to quantify the transmission of C. trachomatis in the population and to assess the impact of screening interventions. Owing to varying assumptions about sexual partnership formation and dissolution and the great uncertainty about critical parameters, such models show conflicting results about the impact of preventive interventions. Here, we perform a detailed evaluation of these models by comparing the partnership formation and dissolution dynamics with data from Natsal 2000, a population-based probability sample survey of sexual attitudes and lifestyles in Britain. The data also allow us to describe the dispersion of C. trachomatis infections as a function of sexual behaviour, using the Gini coefficient. We suggest that the Gini coefficient is a useful measure for calibrating infectious disease models that include risk structure and highlight the need to estimate this measure for other STIs.

Sexual activity-related emergency department admissions: eleven years of experience at a Swiss university hospital

PRINCIPALS: Most people enjoy sexual intercourse without complications, but a significant, if small, number need to seek emergency medical help for related health problems. The true incidence of these problems is not known. We therefore assessed all admissions to our emergency department (ED) in direct relation to sexual intercourse. METHODS: All data were collected prospectively and entered into the ED's centralised electronic patient record database (Qualicare, Switzerland) and retrospectively analysed. The database was scanned for the standardised key words: 'sexual intercourse' (German 'Geschlechtsverkehr') or 'coitus' (German 'Koitus'). RESULTS: A total of 445 patients were available for further evaluation; 308 (69.0%) were male, 137 (31.0%) were female. The median age was 32 years (range 16-71) for male subjects and 30 years (range 16-70) for female subjects. Two men had cardiovascular emergencies. 46 (10.3%) of our patients suffered from trauma. Neurological emergencies occurred in 55 (12.4%) patients: the most frequent were headaches in 27 (49.0%), followed by subarachnoid haemorrhage (12, 22.0%) and transient global amnesia (11, 20.0%). 154 (97.0%) of the patients presenting with presumed infection actually had infections of the urogenital tract. The most common infection was urethritis (64, 41.0%), followed by cystitis (21, 13.0%) and epididymitis (19, 12.0%). A sexually transmitted disease (STD) was diagnosed in 43 (16.0%) of all patients presenting with a presumed infection. 118 (43.0%) of the patients with a possible infection requested testing for an STD because of unsafe sexual activity without underlying symptoms. CONCLUSIONS: Sexual activity is mechanically dangerous, potentially infectious and stressful for the cardiovascular system. Because information on ED presentation related to sexual intercourse is scarce, more efforts should be undertaken to document all such complications to improve treatment and preventative strategies.

Hypersensitivity reactions to quinolones

Quinolones are one of the most important classes of antimicrobial agents discovered in the recent years and one of the most widely used classes of antibiotics in clinical medicine. Their broad spectrum of activity and pharmacokinetic properties make them ideal agents for treating a variety of infections. Their clinical importance is further demonstrated by their activity against a wide range of diseases of public health importance such as anthrax, tuberculosis, bacterial pneumonia, and sexually transmitted diseases. Like other antibiotics, quinolones can cause various, sometimes dangerous hypersensitivity reactions. The underlying pathomechanisms are only poorly understood. Some are thought to be partly non-immune mediated reactions, others are considered to be IgE- or T cell-mediated reactions. This review gives an insight into the different immunological mechanisms leading to the diverse symptoms of quinolone-induced hypersensitivity reactions, with special emphasis on the role of T cells in such reactions.

HHV-8 seroprevalence: a global view

BACKGROUND Human herpes virus 8 (HHV-8) is the underlying infectious cause of Kaposi sarcoma (KS) and other proliferative diseases; that is, primary effusion lymphoma and multicentric Castleman disease. In regions with high HHV-8 seroprevalence in the general population, KS accounts for a major burden of disease. Outside these endemic regions, HHV-8 prevalence is high in men who have sex with men (MSM) and in migrants from endemic regions. We aim to conduct a systematic literature review and meta-analysis in order 1) to define the global distribution of HHV-8 seroprevalence (primary objective) and 2) to identify risk factors for HHV-8 infection, with a focus on HIV status (secondary objective). METHODS/DESIGN We will include observational studies reporting data on seroprevalence of HHV-8 in children and/or adults from any region in the world. Case reports and case series as well as any studies with fewer than 50 participants will be excluded. We will search MEDLINE, EMBASE, and relevant conference proceedings without language restriction. Two reviewers will independently screen the identified studies and extract data on study characteristics and quality, study population, risk factors, and reported outcomes, using a standardized form. For the primary objective we will pool the data using a fully bayesian approach for meta-analysis, with random effects at the study level. For the secondary objective (association of HIV and HHV-8) we aim to pool odds ratios for the association of HIV and HHV-8 using a fully bayesian approach for meta-analysis, with random effects at the study level. Sub-group analyses and meta-regression analyses will be used to explore sources of heterogeneity, including factors such as geographical region, calendar years of recruitment, age, gender, ethnicity, socioeconomic status, different risk groups for sexually and parenterally transmitted infections (MSM, sex workers, hemophiliacs, intravenous drug users), comorbidities such as organ transplantation and malaria, test(s) used to measure HHV-8 infection, study design, and study quality. DISCUSSION Using the proposed systematic review and meta-analysis, we aim to better define the global seroprevalence of HHV-8 and its associated risk factors. This will improve the current understanding of HHV-8 epidemiology, and could suggest measures to prevent HHV-8 infection and to reduce its associated cancer burden.

Higher Risk of Incident HCV-Coinfections in MSM with a Wide HIV Transmission Bottleneck

BACKGROUND  High-risk sexual behaviors have been suggested as drivers of the recent dramatic increase of sexually-transmitted HCV among HIV-infected men who have sex with men(MSM). METHODS  We assessed the association between the HIV-transmission-bottleneck and the prevalence and incidence of HCV-coinfections in HIV-infected MSM from the Swiss-HIV-Cohort-Study(SHCS). As a proxy for the width of the transmission bottleneck we used the fraction of ambiguous nucleotides in Genotypic-Resistance-Tests(GRTs) from recent HIV-infections. We defined a broad bottleneck as a fraction of ambiguous nucleotides exceeding a previously-established threshold(0.5%). RESULTS  From the SHCS, we identified 671 MSMs with available HCV-serologies and with a HIV-GRT sampled during recent infection. Of those, 161(24.0%) exhibited a broad HIV-transmission-bottleneck, 38(5.7%) had at least one positive HCV test, and 26(3.9%) had an incident HCV infection. Individuals with broad HIV-transmission bottlenecks exhibited a twofold-higher odds of having ever experienced an HCV coinfection(OR[95%CI]=2.2[1.1, 4.3]) and a threefold-higher hazard of an incident HCV infection(HR[95%CI]= 3.0[1.4, 6.6]) than individuals with narrow HIV-transmission-bottlenecks. CONCLUSIONS  Our results indicate that the currently occurring sexual spread of HCV is focused on those MSMs that are prone to exhibit broad HIV-transmission-bottlenecks. This is consistent with an important role of high-risk behavior and mucosal-barrier-impairment in the transmission of HCV among MSM.

Chlamydia Control: A Comparative Review from the USA and UK

Chlamydia trachomatis infection (chlamydia) is the most common notifiable bacterial sexually transmitted infection (STI) worldwide. In the United States of America (USA) in 2009, 1,244,180 cases of chlamydia were reported to the Centers for Disease Control and Prevention (CDC), the largest number of cases ever reported to CDC for any notifiable disease [1]. It has been estimated, from population prevalence surveys, that approximately 2 % of sexually active adults aged 18–44 years old in the UK [2] and 2.2 % (CI, 1.8–2.8 %) of the US population aged 14–39 years [3] are infected with chlamydia. This level of prevalence in the USA translates into an estimated 2,291,000 (95 % confidence interval, CI, 1,857,000–2,838,000) chlamydia infections each year [3]. Globally, the World Health Organization (WHO) estimates that there are about 92 million new cases of chlamydia each year [4].

Hepatitis C: a changing epidemic.

Approximately 3% of the world population is estimated to have a chronic hepatitis C virus (HCV) infection and 500,000 individuals die from its consequences yearly. Persons who inject drugs (PWID) bear the majority of the disease burden in high-income countries. Drug substitution programmes have helped reduce HCV transmissions among PWID. However, recent epidemics of sexually transmitted HCV infections in HIV-infected men who have sex with men demonstrated the changing nature of the HCV epidemic. HCV therapy is undergoing a revolution, as new interferon-free, oral treatments eradicate HCV infections in almost all treated patients. As a consequence, the eradication of HCV has become a matter of debate and is becoming an important future public health target. However, for this to be achieved, many challenges need to be addressed, including the poor uptake of HCV testing, the high cost of the new antiviral combinations and the high frequency of re-infections after treatment in some populations.

Hepatitis B vaccination of high risk pregnant women: A clinical trial at Parkland Memorial Hospital

Hepatitis B infection is a major public health problem of global proportions. It is estimated that 2 billion people worldwide are infected by the Hepatitis B virus (HBV) at some point, and 350 million are chronic carriers. The Centers for Disease Control and Prevention (CDC) report an incidence in the United States of 140,000–320,000 infections each year (asymptomatic and symptomatic), and estimate 1–1.25 million people are chronically infected. Hepatitis B and its chronic complications (cirrhosis of the liver, liver failure, hepatocellular carcinoma) responsible for 4,000–5,000 deaths in America each year. ^ One quarter of those who become chronic carriers develop progressive liver disease, and chronic HBV infection is thought to be responsible for 60 million cases of cirrhosis worldwide, surpassing alcohol as a cause of liver disease. Since there are few treatment options for the person chronically infected with Hepatitis B, and what is available is expensive, prevention is clearly best strategy for combating this disease. ^ Since the approval of the Hepatitis B vaccine in 1981, national and international vaccination campaigns have been undertaken for the prevention of Hepatitis B. Despite encouraging results, however, studies indicate that prevalence rates of Hepatitis B infection have not been significantly reduced in certain high risk populations because vaccination campaigns targeting those groups do not exist and opportunities for vaccination by individual physicians in clinical settings are often missed. Many of the high-risk individuals who go unvaccinated are women of childbearing age, and a significant proportion of these women become infected with the Hepatitis B virus (HBV) during pregnancy. Though these women are often seen annually or for prenatal care (because of the close spacing of their children and their high rate of fertility), the Hepatitis B vaccine series is seldom recommended by their health care provider. In 1993, ACOG issued a statement recommending Hepatitis B vaccination of pregnant women who were defined as high-risk by diagnosis of a sexually transmitted disease. ^ Hepatitis B vaccine has been extensively studied in the non-pregnant population. The overall efficacy of the vaccine in infants, children and adults is greater than 90%. In the small clinical trials to date, the vaccine seemed to be effective in those pregnant women receiving 3 doses; however, by using the usual 0, 1 and 6 month regimen, most pregnant women were unable to complete a full series during pregnancy. There is data now available supporting the use of an "accelerated" dosing schedule at 0, 1 and 4 months. This has not been evaluated in pregnant women. A clinical trial proving the efficacy of the 0, 1, 4 schedule and its feasibility in this population would add significantly to the body of research in this area, and would have implications for public health policy. Such a trial was undertaken in the Parkland Memorial Hospital Obstetrical Infectious Diseases clinic. In this study, the vaccine was very well tolerated with no major adverse events reported, 90% of fully vaccinated patients achieved immunity, and only Body Mass Index (BMI) was found to be a significant factor affecting efficacy. This thesis will report the results of the trial and compare it to previous trials, and will discuss barriers to implementation, lessons learned and implications for future trials. ^

Health beliefs and attitudes of HPV among Hispanic parents as predictors of intention to use the HPV vaccine

Human Papillomavirus (HPV) is the most common sexually transmitted disease in the United States. Although HPV prevalence is high in the United States, there are a limited number of research studies that focus on Hispanics, who have higher incidence rates of cervical cancer than their non-Hispanic counterparts. The HPV vaccine introduced in 2006 may offer a feasible solution to the issues surrounding high prevalence of HPV. Due to the high prevalence of HPV infection among adolescents and young adults it has been suggested that HPV vaccination begin prior to onset sexual activity and focus on non-sexually active adolescents and pre-adolescents. Consequently, it has become increasingly important to assess knowledge and awareness of HPV in order to develop effective intervention strategies. This pilot study evaluated the knowledge and health beliefs of Hispanic parents regarding HPV and the HPV vaccine using a newly developed questionnaire based on the constructs of the Health Belief Model. The sample was recruited from an ob-gyn office in El Paso, Texas. Descriptive data show that the majority of the sample was female (94.1%), Hispanic (76.5%), Catholic (64.7%), and had at least a high school education (55.9%). Chi-square analysis revealed that the following variables differed amongst parents who intended to vaccinate their child against HPV and those who did not: religion (p=0.038), perceived severity item "HPV infections are easily treated" (p=0.052), perceived benefits item "It is better to vaccinate a child against an STI before they become sexually active" (p=0.014) and perceived barriers item "The HPV vaccine may have serious side effects that could harm my child" (p=0.004). Univariate logistic regression indicated that religion (OR = 4.8, CI: 1.04, 21.8) and "The HPV vaccine may have serious side effects that could harm my child" (OR = 15.9, CI: 1.73, 145.8) were significant predictors of parental intention to vaccinate. Multivariate logistic regression, using backwards elimination, indicated that religion (OR = 7.7, CI: 1.25, 47.8) and "The HPV vaccine may have serious side effects that may harm my child" (OR = 7.6, CI: 1.15, 50.2) were the best predictive variables for parental intention to vaccinate. ^

HIV incidence estimates and HIV/AIDS concurrent diagnosis in Houston/Harris County

The purpose of this dissertation was to estimate HIV incidence among the individuals who had HIV tests performed at the Houston Department of Health and Human Services (HDHHS) public health laboratory, and to examine the prevalence of HIV and AIDS concurrent diagnoses among HIV cases reported between 2000 and 2007 in Houston/Harris County. ^ The first study in this dissertation estimated the cumulative HIV incidence among the individuals testing at Houston public health laboratory using Serologic Testing Algorithms for Recent HIV Seroconversion (STARHS) during the two year study period (June 1, 2005 to May 31, 2007). The HIV incidence was estimated using two independently developed statistical imputation methods, one developed by the Centers for Disease Control and Prevention (CDC), and the other developed by HDHHS. Among the 54,394 persons who tested for HIV during the study period, 942 tested HIV positive (positivity rate=1.7%). Of these HIV positives, 448 (48%) were newly reported to the Houston HIV/AIDS Reporting System (HARS) and 417 of these 448 blood specimens (93%) were available for STARHS testing. The STARHS results showed 139 (33%) out of the 417 specimens were newly infected with HIV. Using both the CDC and HDHHS methods, the estimated cumulative HIV incidences over the two-year study period were similar: 862 per 100,000 persons (95% CI: 655-1,070) by CDC method, and 925 per 100,000 persons (95% CI: 908-943) by HDHHS method. Consistent with the national finding, this study found African Americans, and men who have sex with men (MSM) accounted for most of the new HIV infections among the individuals testing at Houston public health laboratory. Using CDC statistical method, this study also found the highest cumulative HIV incidence (2,176 per 100,000 persons [95%CI: 1,536-2,798]) was among those who tested in the HIV counseling and testing sites, compared to the sexually transmitted disease clinics (1,242 per 100,000 persons [95%CI: 871-1,608]) and city health clinics (215 per 100,000 persons [95%CI: 80-353]. This finding suggested the HIV counseling and testing sites in Houston were successful in reaching high risk populations and testing them early for HIV. In addition, older age groups had higher cumulative HIV incidence, but accounted for smaller proportions of new HIV infections. The incidence in the 30-39 age group (994 per 100,000 persons [95%CI: 625-1,363]) was 1.5 times the incidence in 13-29 age group (645 per 100,000 persons [95%CI: 447-840]); the incidences in 40-49 age group (1,371 per 100,000 persons [95%CI: 765-1,977]) and 50 or above age groups (1,369 per 100,000 persons [95%CI: 318-2,415]) were 2.1 times compared to the youngest 13-29 age group. The increased HIV incidence in older age groups suggested that persons 40 or above were still at risk to contract HIV infections. HIV prevention programs should encourage more people who are age 40 and above to test for HIV. ^ The second study investigated concurrent diagnoses of HIV and AIDS in Houston. Concurrent HIV/AIDS diagnosis is defined as AIDS diagnosis within three months of HIV diagnosis. This study found about one-third of the HIV cases were diagnosed with HIV and AIDS concurrently (within three months) in Houston/Harris County. Using multivariable logistic regression analysis, this study found being male, Hispanic, older, and diagnosed in the private sector of care were positively associated with concurrent HIV and AIDS diagnoses. By contrast, men who had sex with men and also used injection drugs (MSM/IDU) were 0.64 times (95% CI: 0.44-0.93) less likely to have concurrent HIV and AIDS diagnoses. A sensitivity analysis comparing difference durations of elapsed time for concurrent HIV and AIDS diagnosis definitions (1-month, 3-month, and 12-month cut-offs) affected the effect size of the odds ratios, but not the direction. ^ The results of these two studies, one describing characteristics of the individuals who were newly infected with HIV, and the other study describing persons who were diagnosed with HIV and AIDS concurrently, can be used as a reference for HIV prevention program planning in Houston/Harris County. ^

Mandating the HPV vaccine

Background. HPV is the underlying cause of cervical cancer, a malignant tumor of the female genital tract. Each year, cervical cancer is newly diagnosed in approximately 10,000 women, and over 3,000 women die from the malignancy. In addition, HPV is implicated as a cause of other cancers involving the genital tract, male and female, and the head and neck. ^ Gardasil, a vaccine against HPV, was licensed by the FDA in June 2006. Early study results have shown Gardasil to be safe and effective at preventing HPV infections that are commonly associated with the development of cervical cancer, as well as other HPV-related cancers and genital warts. The vaccine is most effective when administered in childhood, before initial exposure to HPV, which typically occurs shortly after the onset of sexual activity. Accordingly, the CDC's Advisory Committee on Immunization Practices (ACIP) has recommended routine vaccination of females aged 11-12 years. ^ Taking the ACIP recommendation one step further, many states have considered school-based mandates of the HPV vaccine in an attempt to reduce the burden of HPV-related illness, in particular to reduce the disparately high incidence of cervical cancer in medically underserved populations. These mandate attempts have sparked heated debate—highlighting public concerns regarding adolescent sexuality, corporate greed, and vaccines in general. ^ Methods. My research focuses on publicly available sources of information such as medical journals, government reports (federal and state), NGO reports, newspapers, and books. I begin with a background discussion of HPV, cervical cancer, and the HPV vaccine. I then discuss public health policy issues related to vaccines, vaccine mandates, and HPV-related illness. Specifically, I discuss the public health benefit of previous vaccine mandates, the legality of vaccine mandates, and the undue corporate influence on the politics of instituting HPV vaccine mandates. In addition, I examine some of the causes behind the anti-vaccine movement and the controversy surrounding adolescent sexuality as it pertains to the HPV vaccine. In the final section, I focus on the recent failed attempt by Governor Rick Perry to mandate the HPV vaccine in Texas. A retrospective analysis of Governor Perry's policy decisions is undertaken and recommendations are made regarding future attempts to mandate the HPV vaccine, or other vaccines under development for similar sexually transmitted viral diseases such as HIV and herpes simplex. ^ Results. In Texas, as in other states across the country, HPV vaccine mandates faced opposition from those who, while they may support mandates of other vaccines, oppose mandates for the HPV vaccine based largely on the idea that HPV is a sexually transmitted disease—they see responsible sexual behavior as the appropriate method for preventing HPV-related illness. A second major group of opposition comes from those who are generally opposed to all vaccine mandates, due to concerns that mandates are intended primarily for the financial benefit of the pharmaceutical industry or due to concerns—largely unfounded—that vaccines pose a greater health threat than the illnesses they are designed to prevent. ^ Conclusion. In order to reduce opposition to vaccine mandates, care must be taken to educate the public regarding the benefits of vaccination by mobilizing the public health sector, avoid the impression that the decision to institute mandates is rash or pressured by allowing time for open debate, and minimize lobbying efforts by vaccine manufacturers. ^

The influence of HIV/AIDS on the association between genital human papillomavirus and cervical cancer in HIV/AIDS infected women: A literature review

Background: With over 440 million cases of infections worldwide, genital HPV is the most frequent sexually transmitted infection. There are several types including high risk types 16, 18, 58 and 70 among others, which are known to cause cervical cell abnormality and if persistent, can lead to cervical cancer which globally, claims 288,000 lives annually. 33.4 million people worldwide are currently living with HIV/AIDS, with 22.4 million in sub-Saharan Africa where 70% of the female population living with HIV/AIDS is also found. Similar risk factors for HPV, cervical cancer and HIV/AIDS include early age at sexual debut, multiple sexual partners, infrequent condom use, history of STI and immune-suppression. ^ Objectives: To describe the role of HPV in cervical cancer development, to describe the influence of HIV/AIDS on HPV and in the development of cervical cancer and to describe the importance of preventive measures such as screening. ^ Methods: This is a literature review where data were analyzed qualitatively and a descriptive narrative style used to evaluate and present the information. The data came from searches using Pub Med, Cochrane Library, EBSCO Medline databases as well as websites such as the CDC and WHO. Articles selected were published in English over the last 10 years. Keywords used included: 'HPV, cervical cancer and HIV', 'HIV and HPV', 'HPV and cervical cancer', 'HPV infection', 'HPV vaccine', 'genital HPV', 'HIV and cervical cancer', 'prevalence of HIV and cervical cancer' and 'prevalence of cervical cancer'. ^ Results: Women with HIV/AIDS have multiple HPV types, persistent infection, are more likely to present with cervical neoplasia and are at higher risk for cervical cancer. Research also shows that HIV could affect the transmissibility of HPV and that HPV itself could also increase the susceptibility to HIV acquisition. ^ Conclusion: HIV, genital HPV and cervical cancer are all preventable. Need to emphasize programs that aim to increase HIV/AIDS, HPV and cervical cancer awareness. Stress importance of behavior modification such as frequent use of condoms, decreased sexual partners and delayed first intercourse. Facilitate programs for screening and treating HPV, male circumcision, effective management of HAART and HPV vaccination.^

A distinctive clade B HIV type 1 is heterosexually transmitted in Trinidad and Tobago

HIV-1 transmission worldwide is predominantly associated with heterosexual activity, and non-clade B viruses account for the most spread. The HIV-1 epidemic in Trinidad/Tobago and the Caribbean shares many features with such heterosexual epidemics, including a prominent role for coincident sexually transmitted diseases. This study evaluates the molecular epidemiology of HIV-1 in Trinidad/Tobago during a period when abrupt transition from homosexual to heterosexual transmission occurred in the absence of injecting drug use, concomitant with a rapid rise in HIV-1 prevalence in the heterosexual population. Of 31 viral isolates studied during 1987–1995, all cluster with subtype B reference strains. In the analysis of full env genes from 22 early seroconverters, the Trinidad isolates constitute a significant subcluster within the B subtype. The Trinidad V3 consensus sequence differs by a single amino acid from the prototype B V3 consensus and demonstrates stability over the decade of this study. In the majority of isolates, the V3 loop of env contains a signature threonine deletion that marks the lineage of the Trinidad HIV-1 clade B epidemic from pre-1984. No phenotypic features, including syncitium induction, neutralization profiles, and chemokine receptor usage, distinguish this virus population from other subtype B viruses. Thus, although the subtype B HIV-1 viruses being transmitted in Trinidad are genetically distinguishable from other subtype B viruses, this is probably the result of a strong founder effect in a geographically circumscribed population rather than genetic selection for heterosexual transmission. These results demonstrate that canonical clade B HIV-1 can generate a typical heterosexual epidemic.

Illinois HIV/AIDS/STD monthly surveillance update /

Latest issue consulted: May 2005.