Background:
Rift Valley Fever (RVF) is a mosquito-borne zoonotic viral disease that is associated with high morbidity and mortality rates among both human and animals populations in endemic countries [1]. The disease is caused by the Rift valley fever virus (RVFV) that belongs to genus Phlebovirus and family Phenuiviridae [2]. The disease was described for the first time in 1931 in the Rift Valley area in Kenya; this how the disease obtained its name (Ref). The RVFV is transmitted mainly through several species of Aedes andCulex mosquitoes, however, other modes of transmission including vertical transmission from mother to child, sexual transmission, and through the consumption of row milk and uncooked meat were documented [3].
In addition to malaria [4,5], Sudan is endemic with several arboviruses including RVF, Chikungunya, Crimean–Congo hemorrhagic fever (CCHF), dengue, and West Nile virus [1, 6 - 11]. Infections with the RVFV were detected in Sudan in early 1930s [3, 12]. Since then, outbreaks of RVF occur frequently in the country [1,13]. The disease is associated with high abortion among human and domestic animals, therefore, in addition to its negative health affects it has devastating socioeconomic impacts on animals-dependent communities in endemic countries [1,13,14]. Recently, several outbreaks of emerging infectious diseases including RVF occurred in Sudan [1,6-11, 13-17 ]. Additionally, there is rapidly growing evidence about the emergence and spread of invasive diseases vectors in the region including Sudan [10, 18 - 21]. Studies have suggested that the major risk factors that drive this upsurge in the burden and outbreaks of infectious diseases and rapid spread of invasive diseases vectors include Climate change, armed-conflicts and the growing size of population living in humanitarian crisis, globalization, and unplanned urbanization [1,13, 22 - 25]. These risk factors increase the dynamic and the interactions of different populations of human and animals substantially, this in turn magnifies the occurrence of spill over and pathogens sharing events across the different species of diseases-susceptible hosts [26].
Despite the frequent outbreaks of arboviral diseases in Sudan, still there is a huge gap in the local knowledge about the epidemiology, pathology, and the clinical presentation and outcome of patients, particularly in cases of co-infection [3,6]. This gap mainly because of the limited sharing of information about these diseases of local public health and global health concerns [27]. In this communication, we report a case of a differential diagnosis challenge in areas endemic with several causes of febrile illness. Our case, a young (19-year-old) female from central Sudan was confirmed to be co-infected with RVFV malaria.
Case presentation :
A 19-year-old student female from Kampo five, Kenana, White Nile state (Fig. 1), has arrived at the emergency unit of Kenana. She was presented on 23th October 2019; with fever, headache, joint pain, fatigue, and loss of consciousness. The patient is a student resident in kenana district and she reported staying at home for the week before the onset of the symptoms; she reported no contact with sick or apparently ill people or animals. However, she reported being recently exposed to heavy mosquitoes’ bites during that time. She complained from fever, severe diffuse throbbing headache, and joint pain specifically in the knee and elbow. These symptoms were also accompanied by progressively fatigue and muscle pain.
On initial examination, she had a normal pulse rate (74/min), respiratory rate (19/min), blood pressure (95/555), and temperature (39°C). A blood samples were drown from the patient and sent to the local laboratory.
A blood film was made and was positive for the presence of malaria parasite; blood film showed asexual stage trophozoites ofPlasmodium falciparum and ICT was also positive. She was started on malaria treatment, however, she did not show response to the treatment. Therefore, another sample of blood was taken and sent to the central National Public Health Laboratory (NPHL) in Khartoum to be tested for the major viral infections endemic in the country including dengue, RVF, CCHF, and Chikungunya [3]. Nonetheless, considering the recent reports about RVF outbreaks in different states of the country, namely River Nile and Gedaref (Fig. 1), and a sudden increase in abortion rate among cattle and sheep was reported in the area, the sample was prioritized for testing RVFV infection. The result of the real time–polymerase chain reaction (RT-PCR) confirmed infection with RVFV.
For the treatment, the patient received paracetamol infusion for the pain. For the malaria infection, the patient received artemether/lumefantrine four tablets (20 mg artemether; 120 mg lumefantrine per tablet) orally (PO) as an initial dose, followed by four tablets PO after 8 hours, then four tablets PO twice daily (morning and evening) for two days for a total course of 24 tablets. She was advised to stay all day under mosquito net to avoid infecting mosquitoes with RVFV and maintain the virus transmission in the area and she was followed up closely to monitor her case, she responded well and recovered after three days. After two week follow up, she showed no signs of sequela or any damage.