First report of epidemic dengue fever and malaria co-infections among internally displaced persons in humanitarian camps of North Darfur, Sudan

Abstract

This study aimed to investigate an outbreak of a non-malaria, undifferentiated febrile illness, among internally displaced persons (IDPs) living in humanitarian camps in North Darfur, Sudan, in 2019. Methods: An investigation team was deployed to North Darfur to identify suspected cases and collect blood samples, and clinical and demographical data. Blood samples were examined microscopically for Plasmodium spp and tested for dengue (DENV) and yellow fever viruses by reverse transcriptasequantitative polymerase chain reaction. Results: Between September 7 and December 18, 2019, we clinically identified 18 (24%), 41 (54%), and 17 (22%) cases of dengue fever, dengue with warning signs, and severe dengue, respectively. Blood samples were collected from 22% of patients, and 47% of these tested positive for DENV-1 RNA. We confirmed 32 malaria cases with 5 co-infections with DENV. This outbreak of dengue was the first among IDPs in the humanitarian camps. Conclusions: Our findings indicate that dengue has become endemic or that there has been a new introduction. Further epidemiological, entomological, and phylogenetic studies are needed to understand disease transmission in the area. An early warning and response system and an effective health policy are crucial for preventing and controlling arboviruses in Sudan.

The Emergence of Rift Valley Fever in Gedaref State Urges the Need for a Cross-Border One Health Strategy and Enforcement of the International Health Regulations

“…However, it is very likely that our study only identified the severe cases with haemorrhagic disease and missed the mild and/or asymptomatic infections, particularly because many cases are mild or asymptomatic and previous studies suggest that the actual prevalence of RVF is higher than that reported during epidemics [ 8 , 15 , 16 ]. There are many risk factors that might influence the emergence of arboviral diseases in Sudan, including climate change [ 1 , 7 ], conflicts [ 8 , 9 ], increased local and international human movements [ 10 ], as well as trade, unplanned urbanization, and socioeconomic status of the individuals and communities in general [ 17 , 18 , 19 ].…”

“…However, due to the limited diagnostic capacity in the country and the suspected cases of haemorrhagic fever, arboviral diseases infections are only laboratory-tested in the National Public Health Laboratory using limited options of commercially available kits annually provided by the World Health Organization (WHO). This limitation on differential diagnoses and choice of laboratory tests based on the available kits is exacerbated by the high proportion of haemorrhagic fever cases that are left undifferentiated, even for known aetiologic agents during outbreak investigations [ 1 , 8 , 9 , 10 ]. These limitations in the diagnostic capacity in Sudan are further exacerbated by the limited local knowledge about these diseases, including the lack of updates to case definitions that could improve differential diagnoses.…”

“…In particular, the lack of proper documentation and reporting of health information, mainly during health emergencies and epidemics, is greatly compromising decision and policy making as well as misguiding healthcare providers [ 11 ]. This results in delays in the recognition and response to arboviral disease epidemics [ 1 , 3 , 7 , 8 , 9 , 10 ].…”

“…By the end of the rainy season of 2019, in late October, six patients presented to outpatient healthcare clinics in the Gedaref state. However, due to the lack of molecular diagnostic tools in most of the rural and remote areas of Sudan [ 10 ], blood samples from those patients were collected and sent to the National Public Health Laboratory in Khartoum. Samples were tested for the causative viruses of the three most prevalent arboviruses in the country: dengue, chikungunya, and RVF viruses, using rt-qPCR and the commercially available kits (Altona Diagnostics GmbH, Hamburg, Germany).…”

“…Recent studies have highlighted the geographical expansion, increased rate and intensity of these outbreaks, and the overall change in the burden and epidemiologic features of these arboviral diseases in the country. Furthermore, some of these changes were attributed to risk factors such as conflicts and high population dynamics between endemic disease areas and areas without endemic disease [ 1 , 8 , 9 , 10 ], climate change [ 1 , 7 ], globalization and unplanned urbanization [ 8 , 10 ], and the extremely limited diagnostic capacity and lack of practicable health policy for the prevention and control of arboviruses in the country [ 3 , 11 , 12 ].…”