Evaluation of arthropod-borne viruses and other infectious disease pathogens as the causes of febrile illnesses in the Khartoum Province of Sudan

Abstract

The relative importance of arthropod-borne and other disease pathogens as the cause of an outbreak of febrile illnesses was assessed during August 1988, following severe flooding in Khartoum, Sudan. A total of 200 patients with acute febrile illness and 100 afebrile controls were enrolled in the study during October and November 1988; at the Omdurman Military Hospital, Khartoum, Sudan. Sera were tested for IgM and IgG antibodies to six arthropod-borne viruses by an enzyme-linked immunoabsorbent assay, and for similar antibodies to Lassa fever, Crimean-Congo hemorrhagic fever, and Ebola and Marburg viruses by an indirect fluorescence assay. Thick and thin blood smears were examined microscopically for malaria parasites, and fecal and blood specimens were tested for bacteria by standard culture methods. Among the acute and convalescent sera collected from 67 febrile patients, five cases were caused by sandfly fever Sicilian (SFS), six by sandfly fever Naples (SFN), and 12 by unidentified phleboviruses. Of 233 remaining unpaired, acute-phase sera collected from cases and controls, 49 (21%) had IgM antibodies to SFS or SFN, RVF, West Nile (WN), and Chikungunya (CHIK) viruses. Forty-three (22%) of 192 febrile cases and two of the 100 afebrile controls were positive for Plasmodium falciparum, and bacterial enteropathogens were associated with 25 (13%) cases and four controls. These data indicated that phleboviruses and to a lesser extent, WN, P. falciparum, and enterobacterial pathogens were causes of acute febrile illnesses following the 1988 flood in Khartoum, Sudan.

Vectors of Chikungunya virus in Senegal: current data and transmission cycles.

“…12 In Senegal, 185 strains of Chikungunya virus were isolated from 13 mosquito species. Although the infection rates are high in some mosquito species, epidemics seem to be rare.…”

An outbreak of West Nile fever among migrants in Kisangani, Democratic Republic of Congo.

“…For the detection of IgM antibodies against dengue virus (types 1-4), West Nile virus, yellow fever virus, and Sindbis virus, an IgM capture ELISA was used as previously described. 6,16,17 IgM antibodies against Rift Valley fever virus, Chikungunya virus, Crimean Congo hemorrhagic fever virus, and R. typhi were measured by an indirect immunofluorescence assay as described. 18,19 Detection of IgG antibodies.…”

“…1,2 In sub-Saharan African countries such as in Zaire, 3 Uganda, 4 Sudan, 5,6 and Kenya, 7 several outbreaks of febrile illness have been associated with arbovirus infections. Both sporadic and major outbreaks of West Nile fever have also been reported in Europe, with the largest in Romania, which had 393 serologically confirmed cases.…”

No Calm After the Storm: A Systematic Review of Human Health Following Flood and Storm Disasters

“…106 One time series study using health and demographic data found a moderate increase in acute respiratory infections (RR: 1.25; 95% CI, 1.06-1.47) within six months after a flood. 102 Two studies of patients presenting at treatment facilities with acute fever identified malaria in 22% of the patients, 107 dengue fever in 29.4%, and scrub typhus in 1.1% 105 within two to three months and one month post-flood, respectively, and no change was seen in the proportion of people diagnosed with dengue fever who lived in flooded areas four weeks after a flood. 106 A surveillance system study of multiple diseases gave seven alerts for suspected measles, one alert for acute hemorrhagic fever syndrome, two alerts for suspected meningitis, and two alerts for suspected poliomyelitis, but no alerts for acute respiratory infection or unexplained fever in the seven weeks after a flood.…”