Bovine tuberculosis in South Darfur State, Sudan: an abattoir study based on microscopy and molecular detection methods.

Bovine tuberculosis (BTB) is a widespread zoonosis in developing countries but has received little attention in many sub-Saharan African countries including Sudan and particularly in some parts such as Darfur states. This study aimed to detect bovine tuberculosis among caseous materials of cattle slaughtered in abattoirs in South Darfur State, Sudan by using microscopic and PCR-based methods. The study was a cross-sectional abattoir-based study which examined a total of 6,680 bovine carcasses for caseous lesions in South Darfur State between 2007 and 2009. Collected specimens were examined for the presence of acid-fast bacilli (AFB) by using microscopic and culture techniques. Isolated mycobacteria were identified by selected conventional cultural and biochemical tests in comparison to a single tube multiplex PCR (m-PCR) assay which detect Mycobacterium bovis-specific 168-bp amplicons. Of the total 6,680 slaughtered cattle examined in South Darfur, 400 (6 %) showed caseations restricted to lymph nodes (86.8 %) or generalized (13.2 %). Bovine tuberculosis was diagnosed in 12 (0.18 %), bovine farcy in 59 (0.88 %), unidentified mycobacteria in 6 (0.09 %), and missed or contaminated cultures in 7 (0.1 %). Out of 18 cultures with nonbranching acid-fast rods, 12 amplified unique 168-bp sequence specific for M. bovis and subsequently confirmed as M. bovis. With the exception of the reference M. tuberculosis strains, none of the remaining AFB amplified the 337-bp amplicon specific for M. tuberculosis. It could be concluded that bovine tuberculosis is prevalent among cattle in South Darfur representing 4.5 % from all slaughtered cattle with caseous lesions. The study sustains microscopy as a useful and accessible technique for detecting AFB. m-PCR assay proved to be valuable for confirmation of BTB and its differentiation from other related mycobacteriosis, notably bovine farcy.

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

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.

Coxiella burnetii antibody prevalences among human populations in north-east Africa determined by enzyme immunoassay.

Retrospective serosurveys were conducted to determine the prevalence of antibody to phase-I Coxiella burnetii among humans in various locations of north-east Africa. Sera were tested by the enzyme immunoassay (EIA). Initially the EIA was compared with the standard indirect fluorescent antibody (IFA) method for the detection of antibody to C. burnetii. Results indicated that the EIA was slightly less sensitive (88%), but highly specific (94%) and less subjective than the IFA technique. EIA was subsequently adopted for estimating prevalences in the studied human populations. Data obtained by EIA indicated that the prevalence of C. burnetii antibody among adult Egyptian blood donors was 20% (n = 358) in the Suez Canal area, 16% (n = 501) in the Nile Valley and 10% (n = 427) in the Nile Delta. Among adult patients with acute, undifferentiated fever in Egypt, the prevalence was 28% (n = 50) of acute sera, with seroconversion in 12% of convalescent sera. Antibody to C. burnetii was detected by EIA in the sera of 25% (n = 71) of cattle workers in Egypt, 10% (n = 100) of housewives in Sudan, and 37% (n = 104) of adults in north-west Somalia. Following a fever outbreak affecting all ages in northern Sudan, IgG antibody to C. burnetii was present in 54% of the febrile persons (n = 185) and in 53% of afebrile persons (n = 186). IgM antibody to C. burnetii was demonstrated in 29% of the febrile persons and 15% of the afebrile persons. These results implicate C. burnetii as a possibly important and under-reported cause of human disease and undiagnosed fevers in north-east Africa.

HIV-1 infection in Juba, southern Sudan.

Thirty years of civil war in the Sudan have resulted in the isolation of the southern provinces which border Central and East Africa. Consequently, little is known about the epidemiology of HIV-1 infection in this region. To estimate the prevalence of HIV-1 infection in southern Sudan and the risk factors associated with disease transmission, a seroepidemiologic survey was conducted in the township of Juba. Study subjects invited to participate in this study included medical outpatients, inpatients hospitalized for active tuberculosis, and female prostitutes. A total of 401 subjects participated in the study. HIV-1 infection was confirmed in 25 subjects. The prevalence of HIV-1 infection was 19% (8/42) among tuberculosis patients, 16% (8/50) among prostitutes, and 3% (9/309) among outpatients. A significantly higher prevalence of HIV-1 infection was found among female prostitutes when compared to female outpatients: 16% (8/50) vs. 2% (4/178), P < 0.001. Correspondingly, the prevalence of seropositives was significantly higher among male outpatients reporting a history of sexual relations with prostitutes during the prior 10 years compared to male outpatients denying relations with prostitutes: 14% (5/37) vs. 0% (0/94), P = 0.0011. A history of a sexually transmitted disease (STD) was also associated with HIV-1 infection among male outpatients. The findings of this study indicate that HIV-1 infection is highly prevalent in southern Sudan and that prostitutes and their sexual partners represent a major reservoir of HIV infection in this population. This epidemiologic pattern resembles that seen in the African nations neighboring southern Sudan.(ABSTRACT TRUNCATED AT 250 WORDS)

PIP: To estimate the prevalence of HIV-1 infection in southern provinces and the risk factors associated with disease transmission, a seroepidemiologic survey was conducted in the township of Juba. Surveillance sites were established at the medical outpatient clinics of 3 hospitals and 3 primary health care centers, and all persons 16-40 years old attending the study sites were asked to participate. Inpatients hospitalized for active tuberculosis at the Juba University teaching hospital were also enrolled. Female prostitutes were also invited to participate in the study. An epidemiologic questionnaire was completed and 10 ml of venous blood were drawn. All sera were tested for the presence of antibody to HIV-1 at the virology department of the Central Public Health Laboratory, Khartoum, Sudan. A total of 401 subjects participated in the study, and HIV-1 infection was confirmed in 25 subjects. The prevalence of HIV-1 infection was 19% (8/42) among tuberculosis patients, 16% (8/50) among prostitutes, and 3% (9/309) among outpatients. A significantly higher prevalence of HIV-1 infection was found among female prostitutes when compared to female outpatients: 16% (8/50) vs. 2% (4/178), p 0.001. Correspondingly, the prevalence of seropositives was significantly higher among male outpatients reporting a history of sexual relations with prostitutes during the previous 10 years compared to male outpatients denying relations with prostitutes: 14% (5/37) vs. 0% (0/94), p = 0.001. A history of a sexually transmitted disease was also associated with HIV-1 infection among male outpatients. The findings indicate that HIV-1 infection is prevalent in southern Sudan and that prostitutes and their sexual partners represent a major reservoir of HIV infection in this population. This epidemiologic pattern resembles that seen in the African nations neighboring southern Sudan. Further spread of HIV-1 to northern Sudan could occur because of the movement of military personnel and refugees between the north and south of Sudan.

Hepatitis B and C in Juba, southern Sudan: results of a serosurvey.

To compare the epidemiology of hepatitis B virus (HBV) with hepatitis C virus (HCV) in a southern Sudanese population, 666 out-patients attending 6 public clinics in the city of Juba were enrolled in a serosurvey. The average age of subjects was 16 years; 54% were female. Of the 651 samples tested for hepatitis B markers, HBsAg was found in 26% and anti-HBc in 67%. In contrast, only 21 (3%) of the 666 samples were positive for anti-HCV using a second generation immunoblot assay (RIBA-2). Seventeen (81%) of the 21 anti-HCV-positive subjects were positive for anti-HBc, compared to 66% (418/630) of subjects negative for anti-HCV (P = 0.07). None of the anti-HCV-positive subjects reported receiving a prior blood transfusion and only 5 subjects reported a history of jaundice. Nine of the 21 (43%) anti-HCV-positive subjects reported a history of scarification, compared to 23% (148/645) of anti-HCV-negative subjects (P = 0.01). Hepatitis B infection was also associated with scarification by univariate analysis. However, after adjustment for age a history of scarification was not significantly associated with hepatitis C infection, but it was with HBV infection (odds ratio = 1.5, 95% CI 1.0-2.5; P = 0.05). The findings of this study indicate that HCV infection is not highly endemic in this population and that the epidemiology of HCV differs from that of HBV.

Arthropod-borne viral infections associated with a fever outbreak in the northern province of Sudan.

An outbreak of acute febrile illness occurred during August and September 1989 in the Northern Province of Sudan coinciding with a high population density of phlebotomine sandflies. An investigation was conducted to determine whether arboviruses were associated with human illness during this outbreak. Sera were obtained from 185 febrile individuals and tested for IgG and IgM antibody to selected arboviruses by enzyme immunoassay (EIA). The prevalence of IgG antibody was 59% for West Nile (WN), 53% for Sandfly Fever Sicilian (SFS), 32% for Sandfly Fever Naples (SFN), 39% for Yellow Fever (YF), 24% for dengue-2 (DEN-2), 23% for Rift Valley Fever (RVF), 12% for Chikungunya (CHIK) and 5% for Crimean-Congo haemorrhagic Fever (CCHF) viruses. Antibody prevalences tended to increase with age for WN and YF viruses. Antibody rates were about the same for males and females for most of the viruses tested. The prevalence of IgM antibody to SFN was 24% and reciprocal IgM titre exceeded 12,800 for some individuals suggesting that this virus was the cause of recent infection. The prevalence of IgM antibody for the other viruses did not exceed 5%. The study indicated that several arboviruses were endemic and some of them may have caused human disease in the Northern Province of Sudan.

Isolation of Batai virus (Bunyaviridae:Bunyavirus) from the blood of suspected malaria patients in Sudan.

From August through November 1988, 77,500 patients with fever presented to the municipal hospital and to eight government health centers in Kassala, a town of approximately 400,000 individuals in eastern Sudan. A diagnosis of malaria, based primarily on clinical presentation, was made in 14,395 individuals during this four-month period; fevers of unknown origin were diagnosed in 29 patients. A Bunyavirus that was antigenically similar or identical to Batai virus by complement fixation and plaque-reduction neutralization tests was recovered from two of 196 sera collected from patients with acute fever admitted to the municipal hospital in Kassala in October 1988. IgM antibody against this virus was detected by enzyme-linked immunosorbent assay in 7% of the sera from patients with acute fever tested and IgG antibody was detected in 61%.

Acute sporadic hepatitis E in Sudanese children: analysis based on a new western blot assay.

A newly developed Western blot assay for antibody to hepatitis E virus (anti-HEV) was used to evaluate 39 cases of acute pediatric hepatitis and 39 control patients in Khartoum, Sudan. The mean age of cases was 6.5 years (range, 2-14); 64% were male. Acute hepatitis A (IgM anti-HAV-positive) was diagnosed in 13 cases, acute hepatitis B (IgM anti-HBc-positive) in 1, and acute hepatitis E (positive for IgM anti-HEV) in 23 (59%). None of the cases with IgM anti-HAV or IgM anti-HBc had IgM anti-HEV; 3 controls had IgM anti-HEV. Acute hepatitis E was associated with recent contact with a family member or acquaintance with jaundice and the presence of indoor plumbing. The newly developed hepatitis E assay appeared to be specific for the diagnosis of acute icteric non-A, non-B hepatitis. Hepatitis E was found to be the most common cause of acute sporadic hepatitis in children living in an urban area of Africa.

Acute sporadic hepatitis in Sudanese children.

Eighty consecutive cases of acute viral hepatitis and 80 controls selected from a public pediatric clinic were entered into a study of acute sporadic hepatitis in Khartoum, Sudan. Study subjects were 14 years of age or younger and were mainly from a low socioeconomic level. Non-A, non-B hepatitis was diagnosed by exclusion in 35 (43.8%) patients, hepatitis A in 27 (33.8%), acute hepatitis B in 8 (10.0%), possible Epstein-Barr virus (EBV) hepatitis in 1 patient; and dual hepatitis A and B infection in 1 patient. Eight acute cases were positive for HBsAg but negative for anti-HBc IgM and anti-HAV IgM. Delta hepatitis was not identified in any study subject. A household case of jaundice and acquaintance with an individual outside of the household with jaundice during the prior 6 months were associated with non-A, non-B hepatitis. There was no association between parenteral exposure and non-A, non-B hepatitis. These findings suggest that enterically transmitted non-A, non-B hepatitis may be a major cause of acute sporadic hepatitis in children in this area, as well as a cause of epidemic hepatitis.

Serosurvey of prevalence of human immunodeficiency virus amongst high risk groups in Port Sudan, Sudan.

During October, 1987, 593 sera were collected from risk groups in Sudan's only major deepwater port, Port Sudan. The risk groups included prostitutes, lorry drivers and prisoners. A large proportion of the study participants practised high risk behaviour which included sexual promiscuity, medical treatment by injection, scarification and tattooing. Despite high risk behaviour and evidence of a high prevalence of hepatitis B infection, a virus transmitted in a manner similar to HIV, no study participants were positive for HIV infection. This data suggests that the prevalence of HIV infection amongst high risk groups in Port Sudan is very low. These findings confirm a lack of clinical cases of AIDS in hospitalized patients in Port Sudan and the small number of reported cases in other areas of northern Sudan.

PIP: The high prevalence of hepatitis B markers in the Sudan (up to 80% of those surveyed) suggests the potential for a rapid spread of human immunodeficiency virus (HIV) since both viruses are transmitted in similar ways. Although clinical cases of acquired immunodeficiency syndrome (AIDS) have not been reported from Port Sudan, southern Sudan borders on several countries with a high prevalence of HIV infection. Sudan's National AIDS Committee plans a series of surveys to determine the prevalence of HIV infection in high risk groups and the general population in several geographic regions. The 1st such survey was conducted in Port Sudan in 1987 among 593 high-risk individuals (203 prostitutes, 103 lorry drivers, 118 prisoners, and 169 in mixed occupations). The study population included 330 males and 263 females. About half of the participants were married and in the 21-30-year age group. Over 75% had been exposed to hepatitis B and 76% had been treated for malaria, largely through injection. Overall, the incidence of non-sex-related risk factors for HIV infection among Port Sudan subjects was: injection, 48%; scarification, 40%; and tatoos, 38%. 32% reported a prior history of a sexually transmitted disease. 71% of the males had used prostitutes. Surprisingly, no study participants were positive for HIV infection. This finding presumably reflects Port Sudan's geographic isolation from other Central and East African countries with large numbers of HIV-positive individuals. On the other hand, Port Sudan is the site of importation of all goods by sea into the country and many people from other African and Arab countries are associated with the seaport. Thus, once the HIV virus is introduced by infected persons from other areas, the risk factors suggest the potential for rapid transmission.