R ift Valley fever (RVF) is an arboviral disease caused by RVF virus (RVFV; genus Phlebovirus, family Phenuiviridae) (1). RVFV periodically emerges to cause epizootics among livestock and epidemics in persons living nearby (2). It is mainly transmitted by the bite of infected mosquitoes or by direct contact with infected animals and their products (3). In addition, RVFV transmission is maintained vertically among both humans and vector mosquito populations (4,5). The public health threat from arboviral diseases is growing rapidly in Sudan (4,6). Increasing human movement, often arising from armed conflict, is driving several arboviral diseases to emerge in Sudan, usually in the form of undifferentiated febrile illness. Recent epidemics include dengue fever (6,7), Crimean-Congo hemorrhagic fever, West Nile virus disease (8), yellow fever, and chikungunya fever (4). RVF outbreaks represent major public health and economic burdens on endemic countries, particularly those such as Sudan that rely on exporting animals and animal products (3,4,9). In a recent study, RVFV infection was also associated with spontaneous abortion among pregnant women in Sudan (10). We describe a unique, undeclared outbreak of RVF in River Nile state, in northern Sudan, leading to the potential spread of the virus to other states in Sudan or neighboring countries.

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.

BackgroundDengue fever, caused by dengue virus (DENV), has become one of the most important mosquito-borne viral diseases with a steady rise in global incidence, including the Sudan. Sporadic cases and frequent acute febrile illness outbreaks, compatible with Dengue fever, have been reported in El-Gadarif State, Sudan. However, diagnosis was based almost exclusively on clinical signs without confirmatory laboratory investigations. Despite the magnitude of the problem in El-Gadarif State, no information is currently available with regard to the epidemiology of the disease in this State. El-Gadarif State is one of the largest commercial centers in the Sudan. The objective of the present investigation is to estimate the prevalence of DENV antibodies, and determine the potential risk factors associated with seropositivity among residents of El-Gadarif State.MethodsA cross sectional study was conducted in a total of 701residents randomly selected from all 10 localities in El-Gadarif State. The sera from the 701 residents were tested for the presence of DENV-specific immunoglobulin G (IgG) antibodies using a commercially available Anti-dengue IgG enzyme-linked immunosorbent assay (ELISA).ResultsAmong the 701 residents, 334 residents (47.6%) were seropositive for DENV. Mosquito control (OR = 2.73, CI = 1.37–5.87, p-value = 0.001); low income (OR = 2.31, CI: 1.71–6.36, p value = 0.032); sleeping out-doors (OR = 3.73, CI = 2.63–6.23, p-value = 0.013), and localities were determined as potential risk factors for contracting DENV infection.ConclusionsThe prevalence rate of DENV antibodies among residents of El-Gadarif State is significantly high (47.6%). Further epidemiologic studies including, distribution of mosquito vectors and implementation of improved surveillance are urgently warranted for better prediction and prevention of a possible DENV outbreak in El-Gadarif State, Sudan.

This study investigated the causative agent of a haemorrhagic fever epidemic in Gedaref state, south-east Sudan. Six cases of febrile illness with haemorrhagic manifestations presented at outpatient health-clinics. Blood samples were collected from the patients and shipped to Khartoum where they were tested for dengue virus (DENV), chikungunya virus (CHIKV), and Rift Valley fever virus (RVFV) using real-time qPCR. Fifty percent (3/6) of them tested positive for RVFV and neither DENV or CHIKV was detected. All patients were males between 20 and 48 years old who had no history of recent travel. This finding describes the first emergence of RVFV in Gedaref state. Considering that the state hosts a major market of livestock, and it has one of the largest-seasonal open pastures in the country that is usually flooded with herds from the neighbouring states and countries during the rainy season, this emergence could represent a major threat to public health in the region and countries importing animals and/or animal products from east Africa. Therefore, we urge the policymakers of the health and animal resources sectors to implement a one health strategy with a well-established early warning surveillance and response system to prevent the establishment of the disease in the area.

Background The rapidly growing pandemic of coronavirus disease 2019 (COVID-19) has challenged health systems globally. Here we report the first identified infections of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2; aetiology of COVID-19) among recent international arrivals to Sudan and their contacts. Methods Suspected cases were identified clinically and/or epidemiologically. Samples from suspected cases and their contacts were tested in the National Influenza Centre following World Health Organization protocols. Two real-time reverse transcription quantitative polymerase chain reaction assays were used to detect and confirm SARS-CoV-2 infection. Results Seven cases of COVID-19, including two deaths, were confirmed in Sudan between 27 February and 30 March 2020. Suspected cases were identified and tested. As of 30 March, no local transmission was yet reported in the country. Fifty-nine percent of the suspected cases were international travellers coming from areas with current COVID-19 epidemics. Cough and fever were the major symptoms, presented by 65% and 60% of the suspected cases, respectively. By early April, an additional seven cases were confirmed through limited contact tracing that identified the first locally acquired infections in recent contact with imported cases. Conclusions The high mortality rate of COVID-19 cases in Sudan might be due to limitations in test and trace and case management services. Unfortunately, infections have spread further into other states and the country has no capacity for mass community screening to better estimate disease prevalence. Therefore external support is urgently needed to improve the healthcare and surveillance systems.

Background: Acute arboviral infections are distributed worldwide including Sudan, and dengue fever (DENV) is not an exception. The virus activity has recently been frequently reported in Kassala State, eastern Sudan. However, an appropriate epidemiological study would be necessary to provide accurate and precise estimates of the magnitude of recent DENV transmission in this area of endemicity. Methods: In the present investigation, a cross sectional study was conducted to advance beyond the current knowledge of the epidemiology of the disease in Kassala State. The prevalence of the disease was estimated and associated risk factors were determined. Sampled sera were collected and screened for recent dengue transmissionas as determined by DENV-IgM enzyme-linked immunosorbent assay (ELISA). The collection of data for risk assessment was supported by a well designed structured questionnaire. Results: The prevalence of recent DENV infection was estimated to be (11.42%). Potential risk factors to DENV seropsitivity include, age (OR = 3.24, CI = 1.81-5.77,p-value = 0.001); low income (OR = 3.75, CI = 1.57-8.93, p-value = 0.027); mosquito control (OR = 4.18, CI = 2.33-7.51, p-value = 0.004); and localities. Conclusion: The present study showed a high rate of circulating DENV IgM antibodies among the participants of the study (11.42%), suggesting recent transmission of DENV in Kassala State, eastern Sudan. The frequent occurrence of DENV infections necessitates the need for improved surveillance programs and prevention measures to combat this important arboviral disease in Sudan.

Background The public health impact of Chikungunya virus (CHIKV) is often underestimated. Usually considered a mild condition of short duration, recent outbreaks have reported greater incidence of severe illness, fatality, and longer-term disability. In 2018/19, Eastern Sudan experienced the largest epidemic of CHIKV in Africa to date, affecting an estimated 487,600 people. Known locally as Kankasha, this study examines clinical characteristics, risk factors, and phylogenetics of the epidemic in Kassala City. Methodology/Principal findings A prospective cohort of 102 adults and 40 children presenting with chikungunya-like illness were enrolled at Kassala Teaching Hospital in October 2018. Clinical information, socio-demographic data, and sera samples were analysed to confirm diagnosis, characterise illness, and identify viral strain. CHIKV infection was confirmed by real-time reverse transcription-PCR in 84.5% (120/142) of participants. Nine (7.5%) CHIKV-positive participants had concurrent Dengue virus (DENV) infection; 34/118 participants (28.8%) had a positive Rapid Diagnostic Test for Plasmodium falciparum; six (5.0%) had haemorrhagic symptoms including two children with life-threatening bleeding. One CHIKV-positive participant died with acute renal injury. Age was not associated with severity of illness although CHIKV-infected participants were younger (p = 0.003). Two to four months post-illness, 63% of adults available for follow-up (30) were still experiencing arthralgia in one or more joints, and 11% remained moderately disabled on Rapid3 assessment. Phylogenetic analysis showed all CHIKV sequences from this study belonged to a single clade within the Indian Ocean Lineage (IOL) of the East/Central/South African (ECSA) genotype. History of contact with an infected person was the only factor associated with infection (p = 0.01), and likely related to being in the same vector environment. Conclusions/Significance Vulnerability to CHIKV remains in Kassala and elsewhere in Sudan due to widespread Aedes aegypti presence and mosquito-fostering household water storage methods. This study highlights the importance of increasing awareness of the severity and impact of CHIKV outbreaks, and the need for urgent actions to reduce transmission risk in households.

BackgroundCystic echinococcosis (CE) or hydatidosis, caused by the larval stage of Echinococcus granulosus (EG)-complex, is a neglected parasitic disease of public health importance. The disease is endemic in many African and Mediterranean countries including the Sudan. The objective of the present study was to develop and evaluate a real-time loop-mediated isothermal amplification (LAMP) assay for simple and rapid detection of CE in humans and domestic live stock in Sudan.MethodsA set of six LAMP primers, designed from the mitochondrial NADH-1 gene of EG cattle strain of genotype 5 (G5), was used as a target for LAMP assay. The assay was performed at a constant temperature (63 °C), with a real-time follow-up using a LightCycler and fluorochrome dye. Following amplification cycles in a simple water bath, LAMP products were observed for color change by naked eye and were visualized under UV light source using agarose gel electrophoresis.ResultsThe real-time LAMP assay identified a variety of hydatid cysts strains recovered in the Sudan, including Echinococcus canadenses (G6) and Echinococcus ortleppi (G5). Real-time LAMP positive results were detected by the presence of an amplification curve, whereas negative results were indicated by absence of fluorescence detection. Positive LAMP results appeared as a bluish-colored reaction as observed by naked eye, whereas negative LAMP results were observed as purple-colored reaction. The sensitivity studies indicated that the LAMP assay detected as little as a 10 fg of parasite DNA. There was 100 % agreement between results of the LAMP assay and our previously described nested PCR when testing 10-fold serial dilution of DNA extracted from EG-complex hydatid cyst. However, there was no cross-reactivity with other parasites including cysticercus bovis, Fasciola gigantica, and Schistosoma bovis and nucleic acid free samples.ConclusionThe developed LAMP assay would be expected to prove highly significant in epidemiological surveys of CE in developing countries or areas of resource-poor settings for both ease of use and cost.