In 1976, the first cases of Ebola virus disease in northern Democratic Republic of the Congo (th... more In 1976, the first cases of Ebola virus disease in northern Democratic Republic of the Congo (then referred to as Zaire) were reported. This article addresses who was responsible for recognizing the disease; recovering, identifying, and naming the virus; and describing the epidemic. Key scientific approaches used in 1976 and their relevance to the 3-country (Guinea, Sierra Leone, and Liberia) West African epidemic during 2013-2016 are presented. Field and laboratory investigations started soon after notification, in mid-September 1976, and included virus cell culture, electron microscopy (EM), immunofluorescence antibody (IFA) testing of sera, case tracing, containment, and epidemiological surveys. In 2013-2016, medical care and public health work were delayed for months until the Ebola virus disease epidemic was officially declared an emergency by World Health Organization, but research in pathogenesis, clinical presentation, including sequelae, treatment, and prevention, has inc...
Six Brazilian strains of human immunodeficiency virus type 1 (HIV-1) were isolated from infected ... more Six Brazilian strains of human immunodeficiency virus type 1 (HIV-1) were isolated from infected individuals residing in different regions of Brazil between 1987 and 1989. Phylogenetic analysis based on an 860-base pair env fragment, including V 3, V4, V5, and the beginning of gp41, classified the Brazilian strains significantly in genotype B, with interhost distances between 5.9 and 13.1% (mean value, 10%). Amino acid sequence analysis of the V3 loop revealed that three strains contained the North American/European GPGR motif as the tip of the loop whereas in the other three strains proline (P) was substituted by tryptophan (W), methionine (M), or phenylalanine (F). A consensus peptide, Bra-cons, was designed containing GWGR as the tip of the loop. Serological reactivity to the Bra-cons peptide and other V3 peptides (MN, SF2, HBX2, RF, MAL, ELI, Z6, and a Côte d'Ivoire peptide, CI-cons) was compared for 114 HIV-1-positive sera from Rio de Janeiro. Sixty-nine sera (60.5%) reacted with peptides belonging to genotype B, of which 10 sera also reacted with peptides belonging to genotype A (n = 7) and D (« = 3). Eighteen sera (15.8%) had binding antibodies to the Bra-cons peptide. A high number of sera (n = 43; 37.7%) had no antibodies to any of the V3 peptides tested. This result suggests that HIV-1 variants with aberrant V3 loops may circulate in Rio de Janeiro.
American Journal of Obstetrics and Gynecology, 1995
Our aim was to examine maternal, obstetric, and infant characteristics of mother-to-child transmi... more Our aim was to examine maternal, obstetric, and infant characteristics of mother-to-child transmission of human immunodeficiency virus-1 in Nairobi, Kenya. Proviral human immunodeficiency virus-1 was detected by polymerase chain reaction in peripheral blood samples taken between 6 weeks and 3 months of age from 107 children born to human immunodeficiency virus-1 seropositive women. The association of maternal, infant, and obstetric variables with human immunodeficiency virus-1 transmission was examined. The mother-to-child transmission rate was 31% (95% confidence interval 21.6 to 40.2) as defined by the presence of proviral human immunodeficiency virus-1 in the infant. Variables associated with transmission in a univariate analysis included placental inflammation (7/12 in the transmitting group as compared with 2/22 in nontransmitters, p = 0.006), low maternal CD4 and high CD8 percentages (21% and 52%, respectively, in transmitting mothers and 32% and 40% in nontransmitting mothers; p = 0.001), and the gender of the neonate (20/29 infected neonates were female as compared with 26/65 noninfected children, p = 0.02). Sexually transmitted diseases were found more often in transmitting mothers but the differences were not significant. Birth weight and gestational age were not related to vertical transmission of human immunodeficiency virus-1. Risk factors for mother-to-child transmission of human immunodeficiency virus-1 included chorioamnionitis, an impaired maternal immune status, and female gender.
To assess the prevalence of infection with simian immunodeficiency virus (SIV) isolate cpz, a len... more To assess the prevalence of infection with simian immunodeficiency virus (SIV) isolate cpz, a lentivirus closely related to HIV-1, in chimpanzees, and to obtain new SIVcpz isolates. Forty-four wild-captured chimpanzees in Belgium and Côte d'Ivoire were tested for HIV and SIV antibodies. Virus was isolated from the peripheral blood lymphocytes of positive animals and characterized by electron microscopy, Western blot and radioimmunoprecipitation assay. One animal had antibodies that cross-reacted with HIV-1. A lentivirus was isolated and referred to as SIVcpz-ant. With regard to molecular weight patterns, SIVcpz-ant differs from SIVcpz-gab' an HIV-1-related virus isolated from a wild-captured chimpanzee in Gabon. The major core protein, the transmembrane and outer membrane glycoproteins of the SIVcpz-ant strain consistently had higher molecular weights. Significantly more HIV-1-positive sera reacted with the envelope proteins of the Gabonese SIVcpz-gab strain than with the SIVcpz-ant strain. This study shows that natural infection of wild-captured chimpanzees with an HIV-related virus may not be uncommon. The diversity of the two chimpanzee isolates, the different geographical origin and the absence of disease suggest that chimpanzees have not recently become SIVcpz-infected.
The pattern of cases of AIDS in Belgium suggests that Europeans infected with human immunodeficie... more The pattern of cases of AIDS in Belgium suggests that Europeans infected with human immunodeficiency virus (HIV) acquired the infection in Africa. The prevalence of infection was assessed in Belgian advisers and European expatriates and risk factors for infection defined in a case-control study of expatriate men. Fifteen (1.1%) of 1401 Belgian advisers working in Africa and 41 (0.9%) of
ABSTRACT In this Policy Forum, the Joint United Nations Programme on HIV/AIDS (UNAIDS); the World... more ABSTRACT In this Policy Forum, the Joint United Nations Programme on HIV/AIDS (UNAIDS); the World Health Organization (WHO); the World Bank; and the Global Fund to Fight AIDS, TB, and Malaria conclude that, to exploit the opportunities made available by new funding, lower drug prices, and better knowledge of effective action against AIDS, greater global agreement on priorities and coordination are needed. The four agencies have reexamined their partnership to make sure that the strongest possible alliance has been forged to turn back the epidemic. As the fight against AIDS moves increasingly from commitment to action, we are working to ensure that the resources are spent wisely and that our programs are harmonized to help countries mount sustainable and effective AIDS strategies.
In a collaboration of 7 European and United States prospective studies, 44 cases of vertical huma... more In a collaboration of 7 European and United States prospective studies, 44 cases of vertical human immunodeficiency virus type 1 (HIV-1) transmission were identified among 1202 women with RNA virus loads !1000 copies/mL at delivery or at the measurement closest to delivery. For mothers receiving antiretroviral treatment during pregnancy or at the time of delivery (or both), there was a 1.0% transmission rate (8 of 834; 95% confidence interval [CI], 0.4%-1.9%), compared with 9.8% (36 of 368; 95% CI, 7.0%-13.4%) for untreated mothers (risk ratio, 0.10; 95% CI, 0.05-0.21). In multivariate analysis adjusting for study, transmission was lower with antiretroviral treatment (odds ratio [OR], 0.10; ), cesarean section (OR, P ! .001 0.30; ), greater birth weight ( ), and higher CD4 cell count ( ). In 12 P p .022 P p .003 P p .039 of 44 cases, multiple RNA measurements were obtained during pregnancy or at the time of delivery or within 4 months after giving birth; in 10 of the 12 cases, the geometric mean virus load was 1500 copies/mL. Perinatal HIV-1 transmission occurs in only 1% of treated women with RNA virus loads !1000 copies/mL and may be almost eliminated with antiretroviral prophylaxis accompanied by suppression of maternal viremia.
Substantial inequalities exist in cancer survival rates across countries. In addition to preventi... more Substantial inequalities exist in cancer survival rates across countries. In addition to prevention of new cancers by reduction of risk factors, strategies are needed to close the gap between developed and developing countries in cancer survival and the eff ects of the disease on human suff ering. We challenge the public health community's assumption that cancers will remain untreated in poor countries, and note the analogy to similarly unfounded arguments from more than a decade ago against provision of HIV treatment. In resource-constrained countries without specialised services, experience has shown that much can be done to prevent and treat cancer by deployment of primary and secondary caregivers, use of off -patent drugs, and application of regional and global mechanisms for fi nancing and procurement. Furthermore, several middle-income countries have included cancer treatment in national health insurance coverage with a focus on people living in poverty. These strategies can reduce costs, increase access to health services, and strengthen health systems to meet the challenge of cancer and other diseases. In 2009, we formed the Global Task Force on Expanded Access to Cancer Care and Control in Developing Countries, which is composed of leaders from the global health and cancer care communities, and is dedicated to proposal, implementation, and evaluation of strategies to advance this agenda.
Chancroid is a risk factor for heterosexually acquiring HIV. Controlling its spread may reduce HI... more Chancroid is a risk factor for heterosexually acquiring HIV. Controlling its spread may reduce HIV transmission. To develop EIAs for assessing antibody levels and for seroepidemiologic studies. Anti-Haemophilus ducreyi IgA, IgG and IgM EIAs were standardized using a crude cocktail antigen. Evaluation was on sera from Kenya, Rwanda, Thailand and The Gambia. The two-tailed student's t test was used to compare results. The specificity of IgA was 97% (95% confidence interval (CI): 95-99%), of IgG was 92% (95% CI: 89-95%), and of IgM was 99% (95% CI: 98-100%). The sensitivity of IgA was 88% (95% CI: 83-93%), of IgG was 93% (95% CI:89-97%), and of IgM was 78% (95% CI:71-85%) in patients having an ulceration for more than eight days. Thus, 95% (95% CI:92-98%) of the chancroid patients were seropositive for at least one antibody type. The IgG and IgA EIAs were more sensitive in patients older than 24 years of age. Higher IgG rates were found in HIV infected chancroid patients. The EIAs should be useful for studying the kinetics of antibody levels and the epidemiology of H. ducreyi infection.
Large declines in HIV incidence have been reported since 2001, and scientific advances in HIV pre... more Large declines in HIV incidence have been reported since 2001, and scientific advances in HIV prevention provide strong hope to reduce incidence further. Now is the time to replace the quest for so-called silver bullets with a public health approach to combination prevention that understands that risk is not evenly distributed and that effective interventions can vary by risk profile. Different countries have different microepidemics, with very different levels of transmission and risk groups, changing over time. Therefore, focus should be on high-transmission geographies, people at highest risk for HIV, and the package of interventions that are most likely to have the largest effect in each different microepidemic. Building on the backbone of behaviour change, condom use, and medical male circumcision, as well as expanded use of antiretroviral drugs for infected people and pre-exposure prophylaxis for uninfected people at high risk of infection, it is now possible to consider the p...
Objective: To search for the presence of SIV in sooty mangabeys and other monkey species in Côte ... more Objective: To search for the presence of SIV in sooty mangabeys and other monkey species in Côte d'Ivoire, West Africa, and to compare viral isolates with HIV-2 strains from the same region.
The relationship between the genetic variability in the V3 loop and the biological characteristic... more The relationship between the genetic variability in the V3 loop and the biological characteristics of 38 biological clones from 5 European and 7 African HIV-1 isolates belonging to 3 different subtypes (subtype A, B, and D) was investigated. Seventeen of 19 clones displaying a syncytium-inducing (SI) capacity had a positively charged amino acid located at position 11 and/or 25 in the V3 loop sequence. All 19 non-syncytium-inducing (NSI) virus clones lacked such a positive charge at the same positions (p < 0.001). The mean of net charge in the overall V3 loop sequences of the SI clones was higher than that of the NSI clones (p < 0.001). Within the same strains, the SI clones replicated faster/higher than the NSI clones in peripheral blood mononuclear cells (p < 0.01), but not in CD4+ T cell cultures (p > 0.1). All SI clones but only 5 of 19 NSI clones could replicate in human continuous T cell and monocytic cell lines (p < 0.001). A higher number of positively charged amino acid substitutions was found among the subtype D SI clones. Only one of eight autologous sera tested had the ability to neutralize the contemporaneously isolated NSI clones, but not the SI clones. This study indicates that the V3 loop amino acid sequences of HIV-1 biological clones from different origins belonging to different genetic subtypes are clearly correlated with viral syncytium-inducing capacity, cell tropism, and replication rate.
To examine the genetic variation of HIV-1 isolates in Abidjan, Côte d&amp;amp;#39;Ivoire, and... more To examine the genetic variation of HIV-1 isolates in Abidjan, Côte d&amp;amp;#39;Ivoire, and to determine the extent to which phylogenetic trees based on sequence information of part of the env gene containing the principal neutralizing domain are representative for documenting genetic variability. Phylogenetic comparison of 13 HIV-1 strains isolated from patients in Abidjan with previously documented HIV-1 strains of different geographic origin. To sequence a 900 base-pair fragment of the env gene containing V3, V4, V5 and the beginning of gp41 of three to four clones per isolate. Phylogenetic tree analysis was performed with the software package TREECON. Eleven HIV-1 isolates of Abidjan were classified as genotype A, while two were classed as genotypes B and D. Intra-genotype A distances at the nucleotide level were a maximum of 14.1%. Inter-genotype distances between genotype A and genotypes B, C, and D varied from 16.0 to 22.6%. Phylogenetic trees, based on sequence data of a 300 base-pair fragment containing the V3 loop, showed significant differences in tree topology and statistical confidence with phylogenetic trees based on sequence data of the 900 base-pair env fragment. Genotype A Côte d&amp;amp;#39;Ivoire HIV-1 strains, which comprise 11 out of 13 isolates, predominate in Abidjan, which may indicate a local burst of particular variants. Phylogenetic trees should be interpreted with caution when based on a more limited number of nucleotides, such as the V3 region.
Six Brazilian strains of human immunodeficiency virus type 1 (HIV-1) were isolated from infected ... more Six Brazilian strains of human immunodeficiency virus type 1 (HIV-1) were isolated from infected individuals residing in different regions of Brazil between 1987 and 1989. Phylogenetic analysis based on an 860-base pair env fragment, including V 3, V4, V5, and the beginning of gp41, classified the Brazilian strains significantly in genotype B, with interhost distances between 5.9 and 13.1% (mean value, 10%). Amino acid sequence analysis of the V3 loop revealed that three strains contained the North American/European GPGR motif as the tip of the loop whereas in the other three strains proline (P) was substituted by tryptophan (W), methionine (M), or phenylalanine (F). A consensus peptide, Bra-cons, was designed containing GWGR as the tip of the loop. Serological reactivity to the Bra-cons peptide and other V3 peptides (MN, SF2, HBX2, RF, MAL, ELI, Z6, and a Côte d'Ivoire peptide, CI-cons) was compared for 114 HIV-1-positive sera from Rio de Janeiro. Sixty-nine sera (60.5%) reacted with peptides belonging to genotype B, of which 10 sera also reacted with peptides belonging to genotype A (n = 7) and D (« = 3). Eighteen sera (15.8%) had binding antibodies to the Bra-cons peptide. A high number of sera (n = 43; 37.7%) had no antibodies to any of the V3 peptides tested. This result suggests that HIV-1 variants with aberrant V3 loops may circulate in Rio de Janeiro.
In 1976, the first cases of Ebola virus disease in northern Democratic Republic of the Congo (th... more In 1976, the first cases of Ebola virus disease in northern Democratic Republic of the Congo (then referred to as Zaire) were reported. This article addresses who was responsible for recognizing the disease; recovering, identifying, and naming the virus; and describing the epidemic. Key scientific approaches used in 1976 and their relevance to the 3-country (Guinea, Sierra Leone, and Liberia) West African epidemic during 2013-2016 are presented. Field and laboratory investigations started soon after notification, in mid-September 1976, and included virus cell culture, electron microscopy (EM), immunofluorescence antibody (IFA) testing of sera, case tracing, containment, and epidemiological surveys. In 2013-2016, medical care and public health work were delayed for months until the Ebola virus disease epidemic was officially declared an emergency by World Health Organization, but research in pathogenesis, clinical presentation, including sequelae, treatment, and prevention, has inc...
Six Brazilian strains of human immunodeficiency virus type 1 (HIV-1) were isolated from infected ... more Six Brazilian strains of human immunodeficiency virus type 1 (HIV-1) were isolated from infected individuals residing in different regions of Brazil between 1987 and 1989. Phylogenetic analysis based on an 860-base pair env fragment, including V 3, V4, V5, and the beginning of gp41, classified the Brazilian strains significantly in genotype B, with interhost distances between 5.9 and 13.1% (mean value, 10%). Amino acid sequence analysis of the V3 loop revealed that three strains contained the North American/European GPGR motif as the tip of the loop whereas in the other three strains proline (P) was substituted by tryptophan (W), methionine (M), or phenylalanine (F). A consensus peptide, Bra-cons, was designed containing GWGR as the tip of the loop. Serological reactivity to the Bra-cons peptide and other V3 peptides (MN, SF2, HBX2, RF, MAL, ELI, Z6, and a Côte d'Ivoire peptide, CI-cons) was compared for 114 HIV-1-positive sera from Rio de Janeiro. Sixty-nine sera (60.5%) reacted with peptides belonging to genotype B, of which 10 sera also reacted with peptides belonging to genotype A (n = 7) and D (« = 3). Eighteen sera (15.8%) had binding antibodies to the Bra-cons peptide. A high number of sera (n = 43; 37.7%) had no antibodies to any of the V3 peptides tested. This result suggests that HIV-1 variants with aberrant V3 loops may circulate in Rio de Janeiro.
American Journal of Obstetrics and Gynecology, 1995
Our aim was to examine maternal, obstetric, and infant characteristics of mother-to-child transmi... more Our aim was to examine maternal, obstetric, and infant characteristics of mother-to-child transmission of human immunodeficiency virus-1 in Nairobi, Kenya. Proviral human immunodeficiency virus-1 was detected by polymerase chain reaction in peripheral blood samples taken between 6 weeks and 3 months of age from 107 children born to human immunodeficiency virus-1 seropositive women. The association of maternal, infant, and obstetric variables with human immunodeficiency virus-1 transmission was examined. The mother-to-child transmission rate was 31% (95% confidence interval 21.6 to 40.2) as defined by the presence of proviral human immunodeficiency virus-1 in the infant. Variables associated with transmission in a univariate analysis included placental inflammation (7/12 in the transmitting group as compared with 2/22 in nontransmitters, p = 0.006), low maternal CD4 and high CD8 percentages (21% and 52%, respectively, in transmitting mothers and 32% and 40% in nontransmitting mothers; p = 0.001), and the gender of the neonate (20/29 infected neonates were female as compared with 26/65 noninfected children, p = 0.02). Sexually transmitted diseases were found more often in transmitting mothers but the differences were not significant. Birth weight and gestational age were not related to vertical transmission of human immunodeficiency virus-1. Risk factors for mother-to-child transmission of human immunodeficiency virus-1 included chorioamnionitis, an impaired maternal immune status, and female gender.
To assess the prevalence of infection with simian immunodeficiency virus (SIV) isolate cpz, a len... more To assess the prevalence of infection with simian immunodeficiency virus (SIV) isolate cpz, a lentivirus closely related to HIV-1, in chimpanzees, and to obtain new SIVcpz isolates. Forty-four wild-captured chimpanzees in Belgium and Côte d&#39;Ivoire were tested for HIV and SIV antibodies. Virus was isolated from the peripheral blood lymphocytes of positive animals and characterized by electron microscopy, Western blot and radioimmunoprecipitation assay. One animal had antibodies that cross-reacted with HIV-1. A lentivirus was isolated and referred to as SIVcpz-ant. With regard to molecular weight patterns, SIVcpz-ant differs from SIVcpz-gab&#39; an HIV-1-related virus isolated from a wild-captured chimpanzee in Gabon. The major core protein, the transmembrane and outer membrane glycoproteins of the SIVcpz-ant strain consistently had higher molecular weights. Significantly more HIV-1-positive sera reacted with the envelope proteins of the Gabonese SIVcpz-gab strain than with the SIVcpz-ant strain. This study shows that natural infection of wild-captured chimpanzees with an HIV-related virus may not be uncommon. The diversity of the two chimpanzee isolates, the different geographical origin and the absence of disease suggest that chimpanzees have not recently become SIVcpz-infected.
The pattern of cases of AIDS in Belgium suggests that Europeans infected with human immunodeficie... more The pattern of cases of AIDS in Belgium suggests that Europeans infected with human immunodeficiency virus (HIV) acquired the infection in Africa. The prevalence of infection was assessed in Belgian advisers and European expatriates and risk factors for infection defined in a case-control study of expatriate men. Fifteen (1.1%) of 1401 Belgian advisers working in Africa and 41 (0.9%) of
ABSTRACT In this Policy Forum, the Joint United Nations Programme on HIV/AIDS (UNAIDS); the World... more ABSTRACT In this Policy Forum, the Joint United Nations Programme on HIV/AIDS (UNAIDS); the World Health Organization (WHO); the World Bank; and the Global Fund to Fight AIDS, TB, and Malaria conclude that, to exploit the opportunities made available by new funding, lower drug prices, and better knowledge of effective action against AIDS, greater global agreement on priorities and coordination are needed. The four agencies have reexamined their partnership to make sure that the strongest possible alliance has been forged to turn back the epidemic. As the fight against AIDS moves increasingly from commitment to action, we are working to ensure that the resources are spent wisely and that our programs are harmonized to help countries mount sustainable and effective AIDS strategies.
In a collaboration of 7 European and United States prospective studies, 44 cases of vertical huma... more In a collaboration of 7 European and United States prospective studies, 44 cases of vertical human immunodeficiency virus type 1 (HIV-1) transmission were identified among 1202 women with RNA virus loads !1000 copies/mL at delivery or at the measurement closest to delivery. For mothers receiving antiretroviral treatment during pregnancy or at the time of delivery (or both), there was a 1.0% transmission rate (8 of 834; 95% confidence interval [CI], 0.4%-1.9%), compared with 9.8% (36 of 368; 95% CI, 7.0%-13.4%) for untreated mothers (risk ratio, 0.10; 95% CI, 0.05-0.21). In multivariate analysis adjusting for study, transmission was lower with antiretroviral treatment (odds ratio [OR], 0.10; ), cesarean section (OR, P ! .001 0.30; ), greater birth weight ( ), and higher CD4 cell count ( ). In 12 P p .022 P p .003 P p .039 of 44 cases, multiple RNA measurements were obtained during pregnancy or at the time of delivery or within 4 months after giving birth; in 10 of the 12 cases, the geometric mean virus load was 1500 copies/mL. Perinatal HIV-1 transmission occurs in only 1% of treated women with RNA virus loads !1000 copies/mL and may be almost eliminated with antiretroviral prophylaxis accompanied by suppression of maternal viremia.
Substantial inequalities exist in cancer survival rates across countries. In addition to preventi... more Substantial inequalities exist in cancer survival rates across countries. In addition to prevention of new cancers by reduction of risk factors, strategies are needed to close the gap between developed and developing countries in cancer survival and the eff ects of the disease on human suff ering. We challenge the public health community's assumption that cancers will remain untreated in poor countries, and note the analogy to similarly unfounded arguments from more than a decade ago against provision of HIV treatment. In resource-constrained countries without specialised services, experience has shown that much can be done to prevent and treat cancer by deployment of primary and secondary caregivers, use of off -patent drugs, and application of regional and global mechanisms for fi nancing and procurement. Furthermore, several middle-income countries have included cancer treatment in national health insurance coverage with a focus on people living in poverty. These strategies can reduce costs, increase access to health services, and strengthen health systems to meet the challenge of cancer and other diseases. In 2009, we formed the Global Task Force on Expanded Access to Cancer Care and Control in Developing Countries, which is composed of leaders from the global health and cancer care communities, and is dedicated to proposal, implementation, and evaluation of strategies to advance this agenda.
Chancroid is a risk factor for heterosexually acquiring HIV. Controlling its spread may reduce HI... more Chancroid is a risk factor for heterosexually acquiring HIV. Controlling its spread may reduce HIV transmission. To develop EIAs for assessing antibody levels and for seroepidemiologic studies. Anti-Haemophilus ducreyi IgA, IgG and IgM EIAs were standardized using a crude cocktail antigen. Evaluation was on sera from Kenya, Rwanda, Thailand and The Gambia. The two-tailed student&amp;amp;#39;s t test was used to compare results. The specificity of IgA was 97% (95% confidence interval (CI): 95-99%), of IgG was 92% (95% CI: 89-95%), and of IgM was 99% (95% CI: 98-100%). The sensitivity of IgA was 88% (95% CI: 83-93%), of IgG was 93% (95% CI:89-97%), and of IgM was 78% (95% CI:71-85%) in patients having an ulceration for more than eight days. Thus, 95% (95% CI:92-98%) of the chancroid patients were seropositive for at least one antibody type. The IgG and IgA EIAs were more sensitive in patients older than 24 years of age. Higher IgG rates were found in HIV infected chancroid patients. The EIAs should be useful for studying the kinetics of antibody levels and the epidemiology of H. ducreyi infection.
Large declines in HIV incidence have been reported since 2001, and scientific advances in HIV pre... more Large declines in HIV incidence have been reported since 2001, and scientific advances in HIV prevention provide strong hope to reduce incidence further. Now is the time to replace the quest for so-called silver bullets with a public health approach to combination prevention that understands that risk is not evenly distributed and that effective interventions can vary by risk profile. Different countries have different microepidemics, with very different levels of transmission and risk groups, changing over time. Therefore, focus should be on high-transmission geographies, people at highest risk for HIV, and the package of interventions that are most likely to have the largest effect in each different microepidemic. Building on the backbone of behaviour change, condom use, and medical male circumcision, as well as expanded use of antiretroviral drugs for infected people and pre-exposure prophylaxis for uninfected people at high risk of infection, it is now possible to consider the p...
Objective: To search for the presence of SIV in sooty mangabeys and other monkey species in Côte ... more Objective: To search for the presence of SIV in sooty mangabeys and other monkey species in Côte d'Ivoire, West Africa, and to compare viral isolates with HIV-2 strains from the same region.
The relationship between the genetic variability in the V3 loop and the biological characteristic... more The relationship between the genetic variability in the V3 loop and the biological characteristics of 38 biological clones from 5 European and 7 African HIV-1 isolates belonging to 3 different subtypes (subtype A, B, and D) was investigated. Seventeen of 19 clones displaying a syncytium-inducing (SI) capacity had a positively charged amino acid located at position 11 and/or 25 in the V3 loop sequence. All 19 non-syncytium-inducing (NSI) virus clones lacked such a positive charge at the same positions (p < 0.001). The mean of net charge in the overall V3 loop sequences of the SI clones was higher than that of the NSI clones (p < 0.001). Within the same strains, the SI clones replicated faster/higher than the NSI clones in peripheral blood mononuclear cells (p < 0.01), but not in CD4+ T cell cultures (p > 0.1). All SI clones but only 5 of 19 NSI clones could replicate in human continuous T cell and monocytic cell lines (p < 0.001). A higher number of positively charged amino acid substitutions was found among the subtype D SI clones. Only one of eight autologous sera tested had the ability to neutralize the contemporaneously isolated NSI clones, but not the SI clones. This study indicates that the V3 loop amino acid sequences of HIV-1 biological clones from different origins belonging to different genetic subtypes are clearly correlated with viral syncytium-inducing capacity, cell tropism, and replication rate.
To examine the genetic variation of HIV-1 isolates in Abidjan, Côte d&amp;amp;#39;Ivoire, and... more To examine the genetic variation of HIV-1 isolates in Abidjan, Côte d&amp;amp;#39;Ivoire, and to determine the extent to which phylogenetic trees based on sequence information of part of the env gene containing the principal neutralizing domain are representative for documenting genetic variability. Phylogenetic comparison of 13 HIV-1 strains isolated from patients in Abidjan with previously documented HIV-1 strains of different geographic origin. To sequence a 900 base-pair fragment of the env gene containing V3, V4, V5 and the beginning of gp41 of three to four clones per isolate. Phylogenetic tree analysis was performed with the software package TREECON. Eleven HIV-1 isolates of Abidjan were classified as genotype A, while two were classed as genotypes B and D. Intra-genotype A distances at the nucleotide level were a maximum of 14.1%. Inter-genotype distances between genotype A and genotypes B, C, and D varied from 16.0 to 22.6%. Phylogenetic trees, based on sequence data of a 300 base-pair fragment containing the V3 loop, showed significant differences in tree topology and statistical confidence with phylogenetic trees based on sequence data of the 900 base-pair env fragment. Genotype A Côte d&amp;amp;#39;Ivoire HIV-1 strains, which comprise 11 out of 13 isolates, predominate in Abidjan, which may indicate a local burst of particular variants. Phylogenetic trees should be interpreted with caution when based on a more limited number of nucleotides, such as the V3 region.
Six Brazilian strains of human immunodeficiency virus type 1 (HIV-1) were isolated from infected ... more Six Brazilian strains of human immunodeficiency virus type 1 (HIV-1) were isolated from infected individuals residing in different regions of Brazil between 1987 and 1989. Phylogenetic analysis based on an 860-base pair env fragment, including V 3, V4, V5, and the beginning of gp41, classified the Brazilian strains significantly in genotype B, with interhost distances between 5.9 and 13.1% (mean value, 10%). Amino acid sequence analysis of the V3 loop revealed that three strains contained the North American/European GPGR motif as the tip of the loop whereas in the other three strains proline (P) was substituted by tryptophan (W), methionine (M), or phenylalanine (F). A consensus peptide, Bra-cons, was designed containing GWGR as the tip of the loop. Serological reactivity to the Bra-cons peptide and other V3 peptides (MN, SF2, HBX2, RF, MAL, ELI, Z6, and a Côte d'Ivoire peptide, CI-cons) was compared for 114 HIV-1-positive sera from Rio de Janeiro. Sixty-nine sera (60.5%) reacted with peptides belonging to genotype B, of which 10 sera also reacted with peptides belonging to genotype A (n = 7) and D (« = 3). Eighteen sera (15.8%) had binding antibodies to the Bra-cons peptide. A high number of sera (n = 43; 37.7%) had no antibodies to any of the V3 peptides tested. This result suggests that HIV-1 variants with aberrant V3 loops may circulate in Rio de Janeiro.
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