ABSTRACT
Infections with human immunodeficiency virus types 1 and 2 (HIV-1 and HIV-2, respectively) are zoonotic infections. In Africa, the potential exists for additional cross-species transmissions from at least 33 different species of simian immunodeficiency virus (SIV)-infected nonhuman primates (NHPs) through hunting and butchering of these animals for food. Here we describe a highly sensitive and specific enzyme immunoassay (EIA) with chemically modified, multiple antigenic peptides (MAPs) developed for the detection and discrimination of antibodies to SIV genetic lineages. The SIV EIA was developed by using a comprehensive array of MAPs covering two envelope gene regions from all of the SIV lineages for which env sequences were available. Assay sensitivity was evaluated by using 63 plasma or serum samples obtained from primates naturally or experimentally infected with SIVs from 10 genetic lineages. Assay specificity was determined by using 97 known SIV-negative plasma specimens from these same species. Also used in the evaluations were 369 human samples: 198 HIV seronegative, 170 HIV-1 and/or HIV-2 seropositive, and 1 from a human SIVsm infection. Overall assay sensitivity and specificity were 100% with both immunodominant region (IDR) and V3 region MAPs. Although SIV env sequences from talapoin monkeys were not available for specific MAP inclusion, 5 (100%) of 5 SIVtal-infected samples were detected through cross-reactivity with other SIV IDR MAPs used in the assay. The one human SIVsm infection was identified. In conclusion, our SIV MAP EIA proved to be highly sensitive and specific for detecting SIV infections in NHPs and humans. As shown with SIV-infected talapoin monkeys, this assay has the potential to detect previously unidentified SIV strains and should be suitable for sentinel surveillance for potential new cross-species transmissions of SIVs to humans.
Subject(s)
Antigens, Viral/immunology , Immunoenzyme Techniques/methods , Peptides/immunology , Simian Acquired Immunodeficiency Syndrome/diagnosis , Simian Immunodeficiency Virus/immunology , Amino Acid Sequence , Animals , Antigens, Viral/chemistry , HIV Envelope Protein gp120/chemistry , HIV Envelope Protein gp120/immunology , HIV Seropositivity/diagnosis , Haplorhini , Humans , Immunodominant Epitopes/chemistry , Immunodominant Epitopes/immunology , Molecular Sequence Data , Peptide Fragments/chemistry , Peptide Fragments/immunology , Peptides/chemistry , Sensitivity and SpecificityABSTRACT
Monitoring HIV prevalence among selected groups provides important data on infection trends. The present study assessed current HIV prevalence and risk correlates among 255 men and women consecutively attending a sexually transmitted infection clinic in Yaounde, Cameroon. Prevalence of 21.96% and 5.5% were found for HIV and syphilis, respectively, with a significant correlation between the two infections. Although marriage was not a significant predictor for HIV, married men were twice as likely as unmarried men to be infected; no such difference was observed for women. Inconsistent condom use was positively, but not significantly, associated with HIV. Also, age, education, and number of sex partners were not significant correlates of HIV infection. Compared to data collected in 1997, HIV prevalence in this clinic has increased nearly 6%. Our findings highlight the increasing spread of HIV infection in Cameroon and the need for additional control strategies to curb the epidemic.
