Dengue in parts of the Guinea Savannah region of Nigeria and the risk of increased transmission

Abstract

Background Dengue virus (DENV) is spreading to parts of the world where it had not been previously reported. Increased international travel has led to intercontinental importation of dengue by visitors returning from countries in sub-Saharan Africa. Although dengue is well documented in the rain forest region of Nigeria, there is a dearth of information in the Guinea Savannah region, which is a major transit point for local and international visitors in the most populous nation in Africa. We provide preliminary evidence of dengue activity in the Guinea Savannah and highlight the risk factors. Methods Blood was collected from a cross-section of 200 patients attending four hospitals in Anyigba, Kogi State. Anti-dengue antibody was identified using DENV immunoglobulin G (IgG) immunoassays. Questionnaires were used to obtain sociodemographic variables and risk factors. Data were analysed with SPSS version 16.0 for Windows. Results Forty-two (20.5%) participants had anti-DENV IgG antibodies. Persons within the 45–59 y age group were more seropositive, with a rate of 35%. Males were more seropositive compared with females. Marriage, formal education, involvement in business activities and the presence of grasses around homes were associated with higher IgG seropositivity. The presence of open water containers around human dwellings and a lack of mosquito net use are predisposing factors. Conclusions This study identified past exposure to DENV among people in Anyigba, located in the Guinea Savannah region. Proper diagnosis of febrile episodes is required to improve case management and curtail off-target treatment. The high rate of previous exposure of patients to dengue indicates the need to strengthen vector control and dengue surveillance programs.

Socioeconomic risk markers of arthropod-borne virus (arbovirus) infections: a systematic literature review and meta-analysis

“…There were no studies examining YFV. Included studies consisted of 2 cohort studies,16 17 4 case–control studies,18–21 27 cross-sectional studies,22–48 1 nested cross-sectional study within a cohort,49 1 combined cross-sectional and cohort study50 and 1 longitudinal serosurvey 51. Studies were conducted in 23 countries: 4 in low-income countries (Burkina Faso,42 Laos35 and Sudan26 43), 14 in lower-middle-income countries (Ecuador,41 India,19 Jordan,33 37 Kenya,17 36 Nicaragua,16 50 Nigeria,27 31 40 Pakistan,39 Sri Lanka18 and Vietnam34), 13 in upper-middle income (Brazil,23 30 45–47 China,20 24 38 Colombia,49 51 Malaysia,25 Paraguay44 and Thailand29) and 5 in high-income countries/territories (Mayotte (France),28 French Guiana,21 Saudi Arabia,22 Sweden32 and USA48) according to the Development Assistance Committee List of Official Development Assistance Recipients (figure 2).…”

“…The association between education and arboviral infection was analysed in 1 cross-sectional study nested in a cohort, 2 case–control and 22 cross-sectional studies, spanning 18 countries and 6 arboviruses (CHIKV, DENV, JEV, RVFV, SINV and WNV). In these studies, education was classified in distinct ways depending on context, and included level of education,19 24 26 27 29 31–34 36 38–41 43 44 49 schooling age,23 parental education,20 the attainment of any formal education,25 37 42 length of education in years28 and illiteracy 30 45…”

“…Eleven of the 12 studies presented frequencies, 6 presented crude effect estimates and 2 presented adjusted effect estimates. The occupation-related variables analysed were employment status,25 26 30 location of work (inside or outside),23 earnings (above the country’s minimum wage or not),41 employment stability and occupation types 19 27–29 31 40 44. In a study conducted by Chiaravalloti-Neto et al in Brazil, there was a crude association between working outside and seropositivity for DENV, which was lost on adjusting for other socioeconomic and demographic covariates 23.…”

“…Four case–control, three cohort, one longitudinal serosurvey and 18 cross-sectional studies investigated the association between household characteristics and arboviral infections. These studies examined the type or size of residence,19 22–24 30 32 34 44 46 house appearance or quality,20 28 42 number of rooms,22 41 building density,42 household crowding,17 18 22 23 28 30 31 41 43 44 48 50 type or presence of walls,47 wall gaps,47 presence of screens,41 48 residential area,17 21 32 37 waste management42 45 and asset ownership (air conditioning,48 refrigerator,16 television,34 land tenure and home ownership23 41 47 and asset ownership index (presence of electricity, flush toilet, piped water and possession of a television set, radio or refrigerator) 28…”

Temporal Evaluation of Insecticide Resistance in Populations of the Major Arboviral Vector Aedes Aegypti from Northern Nigeria

“…From then onward, several researchers have documented the existence of dengue virus in various parts of the country, including northern Nigeria. Dengue virus antibodies (anti-DENV IgG) have been reported in the Guinea Savannah region of Nigeria with prevalence of 20.5% [20]. Likewise in Kano (north-western Nigeria) high prevalence of dengue IgM has been reported from patients reporting with febrile fever [21].…”