Frequency and Associated Risk Factors of Varicella-Zoster Virus Infection at the Centre Hospitalier Universitaire of Conakry, Guinea

Abstract

Introduction: Varicella-Zoster Virus (VZV) is a strictly human virus (human herpesvirus 3) belonging to the Herpesviridae family and is responsible for chickenpox and herpes zoster. As varicella represents the primary infection, the incidence and severity of herpes zoster increase with age, particularly after 50 years. Although it affects a large number of people, the causes of VZV reactivation are not fully known. Aim: The objective was to determine the hospital frequency of VZV infection as well as its risk factors in the Dermatology-STD Department of Centre Hospitalier Universitaire (CHU) Donka.  Patients and Methods: This was a descriptive and analytical cross-sectional study conducted from August 29, 2019, to February 29, 2020, including all patients diagnosed with varicella or herpes zoster and followed at the Dermatology–STD Department of CHU Donka. Patients were grouped into three groups: those suffering from chickenpox, those suffering from herpes zoster, and a control group free of disease. Data analysis was done using Epi Info software version 7.2. A bivariate analysis was performed, consisting of searching for associations between dependent and independent variables using relative risks (RR) and their confidence intervals. The significance level was set at a p-value < 0.05. Results: During this study, 52 cases of VZV infection were collected out of a total of 1812 admissions in the Dermatology-STD department of CHU Donka. The mean age of patients was 48.03 years +/- standard deviation, and a male predominance was found with a sex ratio of 2.05. The hospital frequency of VZV was 3%, with 39 (2%) cases of herpes zoster and 13 (1%) cases of chickenpox. School-age children were the most represented for chickenpox (53.85%). A statistically significant link was found between chickenpox and age (p=0.001), origin (p=0.01), and overcrowding (p=0.001). A statistically significant link (p < 0.03) was also found between herpes zoster and age, HIV, active and passive smoking, weight loss, hypertension, stress and lack of sleep. Factors significantly associated with varicella were a history of contact, young age, overcrowding, and rural exodus. Factors significantly associated with herpes zoster were immunosenescence and immunodeficiency due to HIV.  Other factors, including stress, lack of sleep, hypertension, weight loss, and smoking, were significantly associated with herpes zoster. Conclusion: The frequency of VZV infection (3%) observed in the Dermatology–STD Department of CHU Donka is notable and concerning, as crowding for chickenpox and HIV/age for herpes zoster to these two conditions and may indicate a clinically relevant burden of varicella and herpes zoster in this population. The limitations of this study lie in the absence of paraclinical examinations as well as the size of our sample, which is relatively small. Therefore, further studies are needed to better understand the risk factors for VZV infection and its potential complications.