Viral Hepatitis B and C Detection among Ebola Survivors and Health Care Workers in Makeni, Sierra Leone

Viral hepatitis B and C infections are among the leading cause of death in Sub-Saharan Africa. Lack of knowledge and awareness in the general population as in health care settings may enhance the propagation of these diseases. We aimed at determining the prevalence of HBV and HCV in Ebola survivors and health care workers (HCWs) of the Makeni town in Sierra Leone. We conducted a cross-sectional study during the last 2013-2016 Ebola outbreak in Makeni among Ebola survivors (N = 68) and 81 Health care workers from Holy Spirit hospital and Loreto clinic, two health care facilities in Makeni district. Serological markers of HBV (HBs Ag, anti-HBs Ab and anti-HBc Ab) and anti-HCV antibodies detection were done using ELISA techniques. The positive detection rates for HBs Ag, anti-HBs Ab and anti-HBc antibodies in Ebola survivors were 23.53% (16/68), 32.35% (22/68) and 88.89% (16/18) respectively. Survivors with a current HBV infection had a positive rate of 38.89% (7/18) and 16.66% (3/18) of them were considered immune due to past HBV infection. HCV prevalence was 26.47% (18/68) and about 10.29% (7/68) were HBV/HCV co-infected. The positive detection rates of HBsAg, anti-HBs Ab and anti-HBc Ab were 37.07% (30/81), 33.33% (27/81) and 30.86% (25/81) respectively in health care workers. We observed that 4.94% (4/81) of the HCWs were currently infected with HBV. Participants considered as immune due to past infection represented 23.47% (19/81) and those immune due to vaccination represented 2.47% (2/81). The prevalence of HCV infection among health staff was 2.47% (2/81) with 1.23% (1/81) being HBV/HCV co-infection. Our findings showed that viral hepatitis infection is a burden for Sierra Leone government. There is an urgent need to develop and implement strategies that could improve population immunization against HBV and vulgarization of HCV treatment programs.

Radio Direction Finding Method to Mitigate Tsunami Risk in Sierra Leone

In this study,the Radio Direction Finding method is proposed for the detection of electromagnetic signals,in the VLF band,to try to anticipate the occurrence of potentially destructive geophysical events.The experimentation concerns the interception of electromagnetic anomalies in Sierra Leone,in the five-day time window,associated with seismic events that could potentially generate tsunamis.The area of investigation is Sierra Leone,whose coastline is subjected to tidal wave hazards triggered by earthquakes generated in the Mid-Atlantic Ridge.Although Sierra Leone is not affected by recurrent earthquakes,there is nevertheless a low probability,estimated at 2 percent,of the occurrence of destructive earthquakes in the next 50 years.Also in estimates,the risk of rogue and potentially damaging waves is estimated to strike the Sierra Leone coast at least once in the next 10 years.The Radio Direction Finding experiment carried out continuously 24/7,has shown a close relationship between increased radio-anomalies,in the frequencies of 6,000 Hz,a time window between electromagnetic anomaly detection and the imminence of an earthquake,and higher frequency times for the risk of earthquake occurrence in the Mid-Atlantic Ridge.

Immunoglobulin G Specific Antibody Level against Ebola Viral Glycoprotein and Nucleoprotein in Ebola Virus Disease Survivors and Their Relatives

Ebola virus disease is a complex zoonosis that is highly virulent in humans. Despite its sorely pathogenic and lethal nature, survivors of this infection and even asymptomatic cases are able to develop both humoral and cellular immunity against several Ebola virus (EBOV) proteins. We aimed at determining immunoglobulin G (IgG) antibodies level against two Ebola viral antigens, the glycoprotein and the nucleoprotein in Ebola survivors and their relatives. Anti-EBOV glycoprotein (GP) and nucleoprotein (NP) IgG antibodies were quantified using ELISA. We enrolled 199 participants in two different sites as follow: 91 survivors at the Loreto clinic and 70 survivors with 38 relatives of Sierra Leone Association of Ebola Survivors Bombali Branch (SLAESB) tested for anti-EBOV NP and anti-EBOV GP IgG antibodies. Our findings revealed that the median anti-EBOV IgG level among survivors was 5.7128 U/ml [IQR: 2.793 - 7.783] for anti-EBOV GP IgG and 4.431 U/ml [IQR: 2.083 - 7.696] for anti-EBOV NP IgG. Survivors relatives had a median anti-EBOV GP IgG level of ?0.7128 U/ml [IQR: -0.903 to -0.04327] and -2.711 U/ml [IQR: -4.01 to -1.918] for anti-EBOV NP IgG. We observed that IgG levels in survivors were higher than in relatives with a significant difference of about 0.0001. The median value of anti-EBOV IgG level among seropositive relatives was 0.7043 U/ml [IQR: 0.5686 to 3.716] for anti-EBOV GP IgG and 4.05 U/ml [IQR: 0.2765 to 7.759] for anti-EBOV NP IgG respectively. Interestingly, we observed that 3.30% of Loreto clinic survivors did not developed anti-EBOV NP IgG antibodies;also about 10% survivors of the SLAESB were not reactive to anti-EBOV NP IgG and 1.43% of these survivors did not express antibodies against the Ebola viral glycoprotein. Our work is consistent with previous published studies showing heterogeneity in both survivors and asymptomatic cases of Ebola infection developing adaptive immunity against EBOV proteins.