Utilizing first void urine for high-risk HPV testing for cervical cancer screening in HIV-positive women in Katete, Zambia.

BACKGROUND: The World Health Organization targets to screen 70% of women worldwide twice for cervical cancer by the year 2030, first by age of 35, and again by the age of 45. However, with the current low screening coverage in many developing countries, this may not be achieved because the invasive sampling method is unacceptable to some. In Zambia, for instance, despite the availability of free cervical cancer screening through the establishment of the Cervical Cancer Prevention Programme, some women are still reluctant to go for screening. First void urine sampling is non-invasive and thus has the potential to increase screening coverage. We aimed to determine the performance of first void urine for high-risk human papillomavirus DNA detection, the prevalence of high-risk HPV, and the acceptability of first void urine sampling. MATERIALS AND METHOD: A comparative cross-sectional study was conducted among 100 HIV- infected women at St Francis' Hospital in Zambia, attending the routine HIV/AIDS services and cervical cancer screening. 17 mL of first void urine sample collected by each participant was immediately mixed with 3 mL of 0.5 M EDTA preservative solution before cervical sample collection by the clinician. For testing, 2 mL of first void urine and 1 mL of the cervical sample were tested using the GeneXpert platform. An interview-based questionnaire was used to gather data on the acceptability of first void urine sampling. Data was analyzed using Stata version 17. RESULTS: The mean age of the participants was 42.58 years (95% CI 40.98-44.19; SD 8.01). High-risk HPV prevalence was 34% (95% CI 24%-43.9%) in both cervical and first void urine samples. Sensitivity and specificity were 84.8% (95% CI 68.1%-94.9%) and 92.3% (83%-97.5%), respectively. There was 89.80% agreement between the samples (κ = 0.77; 95% CI 0.64-0.91). First void urine sampling was highly accepted. CONCLUSION: High-risk HPV DNA can be detected in first void urine samples using the GeneXpert, with a substantial agreement with cervical samples. An affordable preservative such as Ethylenediamine tetraacetic acid can prevent DNA degradation. With optimization, first void urine sampling has the potential to increase screening coverage.

Structural characteristics of measles virus entry.

Measles virus, a member of the genus Morbillivirus, is highly contagious and still shows considerable mortality with over 100000 deaths annually, although efficient attenuated vaccines exist. Recent studies of measles virus haemagglutinin (MeV-H) and its receptor, including crystallographic and electron microscopic structural analyses combined with functional assays, have revealed how the MeV-H protein recognizes its cognate receptors, SLAM and Nectin-4, and how the glycan shield ensures effective vaccination. In addition, the crystal structure of the MeV-F protein indicated its similarity to those of other paramyxoviruses. Taking into account these data, several models of viral entry/membrane fusion of measles viruses and related paramyxoviruses have been proposed. Furthermore, anti-MeV-F inhibitors targeted to specific regions to inhibit MeV-F protein activation were reported, with potency for preventing MeV infection. The inhibitors targeted for entry events may potentially be applied to treatment of MeV-derived diseases, although escape mutations and drug profiles should be considered.

Specificity of Morbillivirus Hemagglutinins to Recognize SLAM of Different Species.

Measles virus (MV) and canine distemper virus (CDV) are highly contagious and deadly, forming part of the morbillivirus genus. The receptor recognition by morbillivirus hemagglutinin (H) is important for determining tissue tropism and host range. Recent reports largely urge caution as regards to the potential expansion of host specificities of morbilliviruses. Nonetheless, the receptor-binding potential in different species of morbillivirus H proteins is largely unknown. Herein, we show that the CDV-H protein binds to the dog signaling lymphocyte activation molecule (SLAM), but not to the human, tamarin, or mouse SLAM. In contrast, MV-H can bind to human, tamarin and dog SLAM, but not to that of mice. Notably, MV binding to dog SLAM showed a lower affinity and faster kinetics than that of human SLAM, and MV exhibits a similar entry activity in dog SLAM- and human SLAM-expressing Vero cells. The mutagenesis study using a fusion assay, based on the MV-H-SLAM complex structure, revealed differences in tolerance for the receptor specificity between MV-H and CDV-H. These results provide insights into H-SLAM specificity related to potential host expansion.