Hospital-based surveillance for viral hemorrhagic fevers and hepatitides in Ghana.

BACKGROUND: Viral hemorrhagic fevers (VHF) are acute diseases associated with bleeding, organ failure, and shock. VHF may hardly be distinguished clinically from other diseases in the African hospital, including viral hepatitis. This study was conducted to determine if VHF and viral hepatitis contribute to hospital morbidity in the Central and Northern parts of Ghana. METHODOLOGY/PRINCIPAL FINDINGS: From 2009 to 2011, blood samples of 258 patients with VHF symptoms were collected at 18 hospitals in Ashanti, Brong-Ahafo, Northern, Upper West, and Upper East regions. Patients were tested by PCR for Lassa, Rift Valley, Crimean-Congo, Ebola/Marburg, and yellow fever viruses; hepatitis A (HAV), B (HBV), C (HCV), and E (HEV) viruses; and by ELISA for serological hepatitis markers. None of the patients tested positive for VHF. However, 21 (8.1%) showed anti-HBc IgM plus HBV DNA and/or HBsAg; 37 (14%) showed HBsAg and HBV DNA without anti-HBc IgM; 26 (10%) showed anti-HAV IgM and/or HAV RNA; and 20 (7.8%) were HCV RNA-positive. None was positive for HEV RNA or anti-HEV IgM plus IgG. Viral genotypes were determined as HAV-IB, HBV-A and E, and HCV-1, 2, and 4. CONCLUSIONS/SIGNIFICANCE: VHFs do not cause significant hospital morbidity in the study area. However, the incidence of acute hepatitis A and B, and hepatitis B and C with active virus replication is high. These infections may mimic VHF and need to be considered if VHF is suspected. The data may help decision makers to allocate resources and focus surveillance systems on the diseases of relevance in Ghana.

Human Enteroviruses isolated during acute flaccid paralysis surveillance in Ghana: implications for the post eradication era.

INTRODUCTION: Surveillance of acute flaccid surveillance (AFP) has been used world-wide to monitor the control and eradication of circulating wild polioviruses. The Polio Laboratory since its accreditation in 1996 has supported the Disease Surveillance Department for AFP surveillance. This study aims to isolate and characterize human enteroviruses from patients with AFP in Ghana. METHOD: Stool suspension was prepared from 308 samples received in 2009 from the surveillance activities throughout the country and inoculated on both RD and L20B cell lines. Isolates that showed growth on L20B were selected for real-time RT-PCR using degenerate and non-degenerate primers and probes. RD isolates were however characterized by microneutralisation technique with antisera pools from RIVM, The Netherlands and viruses that were untypable subjected to neutralization assay using antibodies specific for E71. RESULTS: Of the 308 samples processed, 17 (5.5%) grew on both L20B and RD cells while 32 (10.4%) grew on RD only. All 28 isolates from L20B were characterized by rRT-PCR as Sabin-like polioviruses. No wild poliovirus or VDPV was found. However from the microneutralisation assay, six different enteroviruses were characterized. Among these, Coxsackie B viruses were most predominant followed by Echovirus. Three children from whom non-polio enteroviruses were isolated had residual paralysis while one child with VAPP found. The non-polio enteroviruses circulated throughout the country with the majority (20.7%) from Ashanti region. CONCLUSION: This study showed the absence of wild or vaccine-derived poliovirus circulation in the country. However, the detection of three non-polio enteroviruses and one Sabin-like poliovirus with residual paralysis call for continuous surveillance even in the post polio eradication era.

Interruption of poliovirus transmission in Ghana: molecular epidemiology of wild-type 1 poliovirus isolated from 1995 to 2008.

Described in detail is the molecular epidemiology of wild-type 1 poliovirus circulation in Ghana between 1995-2008, following the implementation of a surveillance system for cases of acute flaccid paralysis and poliovirus infection. Molecular phylogenetic analysis combined with a detailed evaluation of epidemiological indicators revealed that the geographical and temporal circulation of wild-type poliovirus in Ghana was determined by the quality of the implementation of global eradication strategies. The transmission of "indigenous" wild-type 1 poliovirus was eliminated in 1999. However, a drastic reduction in national immunization campaigns resulted in the importation in 2003 and 2008 of wild-type 1 poliovirus from neighboring countries. Both outbreaks were promptly interrupted following resumption of immunization activities. The results detailed here provide scientific evidence that supports the feasibility of polio eradication in Central West Africa, one of the remaining endemic areas for the disease, provided that comprehensive immunization campaigns and sensitive surveillance systems are in place.

The middle to 3' end of the HIV-1 vif gene sequence is important for vif biological activity and could be used for antisense oligonucleotide targets.

The human immunodeficiency virus type-1 (HIV-1)-encoded vif protein is essential for viral replication, virion production, and pathogenicity. HIV-1 Vif interacts with the endogenous human APOBEC3G protein (an mRNA editor) in target cells to prevent its encapsidation into virions. Some studies have established targets within the HIV-1 vif gene that are important for its biologic function; however, it is important to determine effective therapeutic targets in vif because of its critical role in HIV-1 infectivity and pathogenicity. The present study demonstrates that virions generated in transfected HeLa-CD4+ cells, especially from HIV-1 vif frame-shift mutant (3' delta vif; 5561-5849), were affected in splicing and had low infectivity in MT-4 cells. In addition, HIV-1 vif antisense RNA fragments constructed within the same region, notably the region spanning nucleic acid positions 5561-5705 (M-3'-AS), which corresponds to amino acid residues 96-144, significantly inhibited HIV-1 replication in MT-4 and reduced the HIV-1 vif mRNA transcripts and reporter gene (EGFP) expression. The generated virions showed low secondary infection in H9 cells. These data therefore suggest that the middle to the 3' end of vif is important for its biological activity in the target cells.

Intracellular expression of antisense RNA transcripts complementary to the human immunodeficiency virus type-1 vif gene inhibits viral replication in infected T-lymphoblastoid cells.

The human immunodeficiency virus type-1 (HIV-1)-encoded vif protein is essential for viral replication, virion production, and pathogenicity. HIV-1 vif interacts with the endogenous human APOBEC3G protein (an mRNA editor) in target cells to prevent its virions from encapsidation. Although some studies have established targets within the HIV-1 vif gene that are important for its biologic function, it is however important to further screen for effective therapeutic targets in the vif gene that could interfere with the HIV-1 vif-dependent infectivity and pathogenicity. This report demonstrates that HIV-1 vif antisense RNA fragments constructed within mid-3' region, notably the region spanning nucleic acid positions 5561-5705 (M-3'-AS), significantly inhibited HIV-1 replication in MT-4 and H9-infected cells and reduced the HIV-1 vif mRNA transcripts. These data clearly suggest that the above vif fragment, which corresponds to amino acid residues 96-144, could be an effective novel therapeutic target site for gene therapy applications, for the control and management of HIV-1 infection, due to its strong inhibition of HIV-1 replication in cells.

Down regulation of human immunodeficiency virus type-1 (HIV-1) expression by Vif antisense RNA expression vectors in transfected cells.

The HIV-1 vif gene is a potential candidate in the quest for anti-retroviral interventions, due to its unique role in the target cell infection. We employed the antisense RNA strategy to determine the antiviral activity of intracellularly expressed anti-sense RNAs of various lengths complementary to the targeted HIV-1 vif gene. Expression vectors mediating the delivery of the vif-ORF, 5'-Vif, M-vif, and 3'-vif antisense RNAs under the CMV promoter were constructed using pcDNA 3.1. The COS cells transfected with the antisense vectors showed a steady-state of antisense RNA expression levels. In contrast, those co-transfected with the Infectious molecular clone, pNL-E, exhibited a significant reduction in the steady-state antisense RNA levels, which correlated with a significant reduction in p24 antigen production. Thus, this expression method for these antisense RNAs provides a promising gene therapy strategy for HIV-1.