There are only few data concerning persistence of neutralizing antibodies (NAbs) among SARS-CoV-2-infected healthcare workers (HCW). These individuals are particularly exposed to SARS-CoV-2 infection and at potential risk of reinfection. We followed 26 HCW with mild COVID-19 three weeks (D21), two months (M2) and three months (M3) after the onset of symptoms. All the HCW had anti-receptor binding domain (RBD) IgA at D21, decreasing to 38.5% at M3 (p < 0.0001). Concomitantly a significant decrease in NAb titers was observed between D21 and M2 (p = 0.03) and between D21 and M3 (p < 0.0001). Here, we report that SARS-CoV-2 can elicit a NAb response correlated with anti-RBD antibody levels. However, this neutralizing activity declines, and may even be lost, in association with a decrease in systemic IgA antibody levels, from two months after disease onset. This short-lasting humoral protection supports strong recommendations to maintain infection prevention and control measures in HCW, and suggests that periodic boosts of SARS-CoV-2 vaccination may be required.

Background: HIV, HBV and HCV remain a global public health concern especially in Africa. Prevalence of these infections is changing and identification of risk factors associated with each infection in Mali is needed to improve medical care. Methods: We conducted a cross-sectional study of all individuals donating blood (n = 8207) in 2018 to the blood bank at university hospital in Bamako, Mali, to assess prevalence and risks factors associated with HIV, HBV, HCV and syphilis infections. Results: HIV-seroprevalence was 2.16% and significantly increased with age, being married and decreasing education level. In multivariate analysis, after adjustements with age, marital status and geographical setting, only education level was associated with HIV-infection (OR, 1.54 [95% CI, 1.15–2.07], p = 0.016). HBsAg prevalence was 14.78% and significantly increased with to be male gender. In multivariate analysis, adjusting for age, marital status and type of blood donation, education level (OR, 1.17 [95%CI, 1.05–1.31], p = 0.02) and male gender (OR, 1.37 [95%CI, 1.14–1.65], p = 0.005) were associated with HBV-infection. HCV-prevalence was 2.32% and significantly increased with living outside Bamako. In multivariate analysis, adjusting for gender, age and education level, living outside Bamako was associated with HCV-infection (OR, 1.83 [95% CI, 1.41–2.35], p < 0.001). Syphilis seroprevalence was very low (0.04%) with only 3 individuals infected. Contrary to a prior study, blood donation type was not, after adjustments, an independent risk factor for each infection. Conclusions: Overall, HIV and HBV infection was higher in individuals with a lower level of education, HBV infection was higher in men, and HCV infection was higher in people living outside of Bamako. Compared to studies performed in 1999, 2002 and 2007 in the same population, we found that HIV and HCV prevalence have decreased in the last two decades whereas HBV prevalence has remained stable. Our finding will help guide infection prevention and treatment programs in Mali.

Kaposi’s sarcoma-associated herpesvirus (KSHV), also called human herpesvirus 8 (HHV-8), is an oncogenic virus belonging to the Herpesviridae family. The viral particle is composed of a double-stranded DNA harboring 90 open reading frames, incorporated in an icosahedral capsid and enveloped. The viral cycle is divided in the following two states: a short lytic phase, and a latency phase that leads to a persistent infection in target cells and the expression of a small number of genes, including LANA-1, v-FLIP and v-cyclin. The seroprevalence and risk factors of infection differ around the world, and saliva seems to play a major role in viral transmission. KSHV is found in all epidemiological forms of Kaposi’s sarcoma including classic, endemic, iatrogenic, epidemic and non-epidemic forms. In a Kaposi’s sarcoma lesion, KSHV is mainly in a latent state; however, a small proportion of viral particles (<5%) are in a replicative state and are reported to be potentially involved in the proliferation of neighboring cells, suggesting they have crucial roles in the process of tumorigenesis. KSHV encodes oncogenic proteins (LANA-1, v-FLIP, v-cyclin, v-GPCR, v-IL6, v-CCL, v-MIP, v-IRF, etc.) that can modulate cellular pathways in order to induce the characteristics found in all cancer, including the inhibition of apoptosis, cells’ proliferation stimulation, angiogenesis, inflammation and immune escape, and, therefore, are involved in the development of Kaposi’s sarcoma.

To assess sexually transmitted infections (STIs) prevalence, antimicrobial resistance and cervical lesions among women from Sikasso, Mali. HIV-infected (n=44) and HIV-uninfected (n=96) women attending cervical cancer screening were included. Human papillomavirus (HPV), Chlamydia trachomatis (CT), Mycoplasma genitalium (MG), Neisseria gonorrhoeae (NG) and Trichomonas vaginalis (TV) detections were performed by PCR and herpes simplex virus (HSV-1/2) serological status by ELISA assays. Antibiotics-resistance tests were performed for MG and NG positives cases. We evidenced a high prevalence of high-risk HPV (hrHPV) infection (63%), associated with cervical lesion in 7.5% of cases and an unusual hrHPV distribution with HPV31, HPV56 and HPV52 being the most prevalent. According to HIV-status, hrHPVs distribution was also different (HIV-positive: HPV35/31/51-52-56 and HIV-negative: HPV31/56/52). HSV-2 seroprevalence was 49%, and prevalence of other STIs as follow: CT: 4%, MG: 9%, NG: 1% and TV: 7%. Five out of 9 MG-positive specimens and the NG strains obtained were fluoroquinolone-resistant. Our results showed a high prevalence of hrHPV and fluoroquinolone-resistance in several NG and MG strains. Further studies are required to confirm these data in Mali and to improve prevention, screening and management of cervical cancer and others STIs in women.