Use of Envelope Domain III Protein for the Detection of IgG Type Antibodies Specific to Zika Virus by Indirect ELISA.

Zika virus (ZIKV) diagnostics are crucial for proper antenatal and postnatal care and also for surveillance and serosurvey studies. Since the viremia during ZIKV infection is fleeting, serological testing is highly valuable to inform diagnosis. However, current serology tests using whole virus antigens frequently suffer from cross reactivity issues, delays, and technical complexity, especially in low and middle income countries (LMICs) and endemic countries. Here, we describe an indirect ELISA to detect specific IgG antibodies using the ZIKV envelope domain III (EDIII) protein expressed in Drosophila S2 cells as an immunogen. Using a total of 367 clinical samples, we showed that the EDIII-ELISA was able to detect IgG antibodies against ZIKV with high sensitivity of 100.0% and specificity of 94.7% when compared to plaque reduction neutralization tests (PRNTs) as the gold standard and using 0.208 as the cut-off OD value. These results show the usefulness of the recombinant envelope domain III as an alternative to standard whole virus proteins for ZIKV diagnostics as it improves the sensitivity and specificity of IgG ELISA assay when used as an immunogen. This method should, therefore, be extended to serological diagnostic techniques for other members of the flavivirus genus and for use in IgM diagnostic testing.

Human Papillomavirus infection in senegalese female sex workers.

OBJECTIVES: Several studies have documented the HPV genotypes in the Senegalese general population. The objective was to explore the HPV genotype distribution in Senegalese FSWs in order to assess the potential relevance of currently-available vaccines. METHODS: Vaginal swabs samples collected as part of the National Integrated Biological and Behavioral Survey in 14 regions throughout the country were randomly selected for HPV testing using bead-based multiplex genotyping (TS-MPG). RESULTS: Among the 436 FSW samples analyzed, the overall HPV prevalence was 79.8% (N = 348), with 70.1% (N = 244) cases presenting as multiple infections. High Risk HPV genotypes affecting at least 10% of FSWs included in order of decreasing frequency: 52, 16, 35, 51, 33, 31, 18, and 45. Sixty-seven (15.4%) FSWs were HIV positive and they were significantly more affected by HPV (94% vs 77%; p < 0.01) than seronegative FSWs as well as infections with multiple genotype. CONCLUSION: The present study indicates that FSW in Senegal experience a high burden of HPV infection with a high frequency of coinfection with HIV and multiple HPV genotypes. Public health interventions for this key population should include an earlier cervical dysplasia/cancer detection and preventative measures such as vaccination programs that must consider the HPV genotype distribution.

Viral and Bacterial Etiologies of Acute Respiratory Infections Among Children Under 5 Years in Senegal.

Acute respiratory infections (ARIs) are the leading cause of infectious disease-related morbidity, hospitalization, and morbidity among children worldwide. This study aimed to assess the viral and bacterial causes of ARI morbidity and mortality in children under 5 years in Senegal. Nasopharyngeal samples were collected from children under 5 years who had ARI. Viruses and bacteria were identified using multiplex real-time reverse transcription-polymerase chain reaction and conventional biochemical techniques, respectively. Adenovirus was the most prevalent virus (50%; n = 81), followed by influenza virus (45.68%, n = 74), rhinovirus (40.12%; n = 65), enterovirus (25.31%; n = 41), and respiratory syncytial virus (16.05%; n = 26), whereas Streptococcus pneumoniae (17%; n = 29), Moraxella catarrhalis (15.43%; n = 25), and Haemophilus influenzae (8.02%; n = 13) were the most commonly isolated bacteria. Virus pathogens seem more likely to be more prevalent in our settings and were often associated with bacteria and S. pneumoniae (6%; 16) coinfection.