Seroprevalence, knowledge, and practices of Dengue and Chikungunya in Dar es salaam and Zanzibar: selected hospital-based cross-sectional study

Abstract

The potential shift of significant causes of febrile illnesses from malaria to non-malarial febrile illnesses, including arboviral diseases such as Chikungunya and Dengue, is of great concern. Two cross sectional studies were conducted at Mnazi mmoja in Zanzibar and Temeke hospital in Dar es Salaam Tanzania. The first study assessed the prevalence, knowledge, and practices regarding Chikungunya and Dengue, among individuals attending outpatient departments at Mnazi mmoja in Zanzibar and Temeke hospital in Dar es Salaam Tanzania. The second study involved serological testing of blood samples from the blood bank at Temeke Referral Hospital in Dar es Salaam and the National Blood Bank Unit in Zanzibar was conducted. Seropositive IgM samples from Temeke hospital in Dar es Salaam were 3/101 (2.97%) for Chikungunya and 1/101 (0.9%) for Dengue, while samples from Zanzibar were all IgM negative for both viruses. Chikungunya IgG seropositivity was significantly higher (p≤0.05) in Temeke hospital in Dar es Salaam 21/101 (21.2%) than Zanzibar 22/180 (12.2%). There was no significant difference in Dengue IgG seropositivity between Temeke hospital in Dar es Salaam 44/101 (43.5%) and Zanzibar 68/180 (37.8%). A total of 332 patients were recruited through a systematic random sampling technique from Zanzibar and Dar es Salaam hospitals. Participants from Dar-es-Salaam had demonstrated lower preventive practices as compared to those from Zanzibar. Only 10.2% of all participants had high knowledge of Dengue and Chikungunya, while only 4.5% were aware of preventive practices. Our results show continuing exposure of Dengue and Chikungunya virus in Tanzania, it associates with low awareness and poor preventive practices. If steps are not taken, may act as a template for big outbreaks when an appropriate condition occurs. Therefore the inclusion of Dengue and Chikungunya in active surveillance program is proposed.