Human papillomavirus prevalence among unvaccinated young female college students in Botswana: A cross-sectional study.

BACKGROUND: Human papillomavirus (HPV) is a sexually transmitted infection and a causative agent of cervical cancer. It is common in adolescent girls and young women, and the majority of infections are transient and asymptomatic. In Botswana, there are currently no data on the HPV prevalence against which the impact of prophylactic HPV vaccines can be measured. OBJECTIVES: To establish a baseline HPV prevalence in an unvaccinated cohort of young women. METHODS: Women aged ≥18 years were recruited from the University of Botswana between September 2016 and May 2020. Demographic and behavioural characteristics of participants were collected. Subsequently, cervicovaginal swabs were obtained and tested for HPV using polymerase chain reaction-restriction fragment length polymorphism. We determined the prevalent HPV types, and evaluated the risk factors associated with HPV positivity. RESULTS: A total of 978 young women were recruited. Overall, there were 589 (60.2%) participants with HPV infection and 12 (1.2%) with HIV. The median (interquartile range) age of the study participants was 19 (18 - 20) years. Multivariate logistic regression analysis showed that significant factors associated with HPV positivity were sexual activity (adjusted odds ratio (aOR) 2.06; 95% confidence interval (CI) 1.49 - 2.63; p<0.001), number of sex partners ≥3 (aOR 2.10; 95% CI 1.39 - 3.18; p<0.001), and smoking (aOR 2.00; 95% CI 1.26 - 3.20; p=0.004). CONCLUSION: Our results demonstrate for the first time the prevalence of HPV in unvaccinated young women in Botswana. We found a high prevalence of HPV infection, with statistical differences with different risk factors. This finding supports the need for HPV vaccination strategies for females prior to sexual debut to reduce the future burden of cervical cancer in Botswana.

Evaluation of bloodsucking arthropod bite as possible risk co-factor in Human herpesvirus-8 transmission route.

Human herpesvirus-8 non-sexual transmission occurs primarily from mother-to-child. The viral load in saliva is higher than in other human fluids. Moreover, there is evidence that bloodsucking arthropod bites induce an inflammatory/immune response that facilitates viral replication. We aim to explore possible risk factors in mother-to-child HHV-8 transmission associated with traditional methods which involve the use of saliva to relieve the irritation and skin reaction caused by arthropod bites. We administered questionnaires to 2244 children from several African countries and Italy. Descriptive statistics and logistic regression were used in the analysis of the answers to evaluate the relationships between the use of traditional methods and other risk factors. The use of traditional methods is high in Cameroon (63.0%) and Uganda (39.9%), intermediate in Senegal (26.7%) and Italy (21.7%), low in Madagascar (6.7%). Statistical analyses show significant direct relationships between the use of traditional methods, skin reactions to the bite and their duration in Cameroon, Uganda and Senegal. The use of saliva and herbs applied by the mothers on the child's skin, is a common habit in Africa. If this practice plays a role in the HHV-8 transmission, then, it could provide the basis for interventions capable of reducing the health impact of the infection in children in tropical areas.

Genetic complexity and gametocyte production of Plasmodium falciparum in Fulani and Mossi communities in Burkina Faso.

We have examined Plasmodium falciparum gametocyte prevalence, density and their genetic complexity among children of 2 sympatric ethnic groups (Mossi and Fulani) in villages in Burkina Faso. The 2 groups are known to have distinct differences in their susceptibility and immune responses to malaria. We used RT-PCR and sequence-specific probes to detect and type RNA of the gametocyte-specific protein Pfs48/45. There were no differences in detection rates of asexual forms and gametocytes among the 2 groups, using PCR and RT-PCR, respectively. However, there were significant differences in densities of asexual forms and gametocytes, which were both higher among Mossi than Fulani. Both asexual forms and gametocyte densities were influenced by age and ethnicity. Multiple-clone infections with more than 1 gametocyte genotype were equally prevalent among Fulani and Mossi. These differences can most probably be attributed to genetic differences in malaria susceptibility in the 2 ethnic groups.

Haemoglobin C protects against clinical Plasmodium falciparum malaria.

Haemoglobin C (HbC; beta6Glu --> Lys) is common in malarious areas of West Africa, especially in Burkina Faso. Conclusive evidence exists on the protective role against severe malaria of haemoglobin S (HbS; beta6Glu --> Val) heterozygosity, whereas conflicting results for the HbC trait have been reported and no epidemiological data exist on the possible role of the HbCC genotype. In vitro studies suggested that HbCC erythrocytes fail to support the growth of P. falciparum but HbC homozygotes with high P. falciparum parasitaemias have been observed. Here we show, in a large case-control study performed in Burkina Faso on 4,348 Mossi subjects, that HbC is associated with a 29% reduction in risk of clinical malaria in HbAC heterozygotes (P = 0.0008) and of 93% in HbCC homozygotes (P = 0.0011). These findings, together with the limited pathology of HbAC and HbCC compared to the severely disadvantaged HbSS and HbSC genotypes and the low betaS gene frequency in the geographic epicentre of betaC, support the hypothesis that, in the long term and in the absence of malaria control, HbC would replace HbS in central West Africa.