Antidiarrheal activity of some selected Nigerian plants used in traditional medicine

Context: Herbal preparations of the various parts of Vitellaria paradoxa, Neorautanenia mitis, Senna surattensis, and Hydnora abyssinica have been used in the Nigerian traditional medical practice to treat the symptoms of diarrhea in humans and animals. Aims: This study aims to validate claims of the traditional use of these plants in the treatment of diarrhea and provide a scientific basis for further studies. Materials and Methods: The median lethal dose (LD50) values of the extracts were obtained using the Limit test. Castor oil induced diarrhea and intestinal transit (motility) models in albino rats were used to determine the antidiarrheal activity. Graded doses of the extracts were administered to 3 test groups, while the positive control groups were given standard drugs (atropine and loperamide) and the negative control groups received distilled water per os. Results: The LD50 was considered higher than 2000 mg/Kg for all the extracts. In the castor oil-induced diarrhea model, the highest percentage inhibition of defecation was observed in the test groups treated with the extracts of H. abyssinica (82%) followed by S. surattensis (81%), N. mitis (66%), and V. paradoxa (32%). H. abyssinica extract significantly decreased the intestinal transit of charcoal meal compared to the other extracts. Conclusion: The antidiarrheal activities of all the extracts give credence to their traditional use. H. abyssinica comparatively had the best antidiarrheal activity and has the potential as an antidiarrheal agent. Thus, the need for further studies of this extract to investigate active fractions, isolate and characterize active compounds, and determine their activities and safety

Highly Pathogenic Avian Influenza Virus Subtype H5N1 in Africa: A Comprehensive Phylogenetic Analysis and Molecular Characterization of Isolates

Highly pathogenic avian influenza virus A/H5N1 was first officially reported in Africa in early 2006. Since the first outbreak in Nigeria, this virus spread rapidly to other African countries. From its emergence to early 2008, 11 African countries experienced A/H5N1 outbreaks in poultry and human cases were also reported in three of these countries. At present, little is known of the epidemiology and molecular evolution of A/H5N1 viruses in Africa. We have generated 494 full gene sequences from 67 African isolates and applied molecular analysis tools to a total of 1,152 A/H5N1 sequences obtained from viruses isolated in Africa, Europe and the Middle East between 2006 and early 2008. Detailed phylogenetic analyses of the 8 gene viral segments confirmed that 3 distinct sublineages were introduced, which have persisted and spread across the continent over this 2-year period. Additionally, our molecular epidemiological studies highlighted the association between genetic clustering and area of origin in a majority of cases. Molecular signatures unique to strains isolated in selected areas also gave us a clearer picture of the spread of A/H5N1 viruses across the continent. Mutations described as typical of human influenza viruses in the genes coding for internal proteins or associated with host adaptation and increased resistance to antiviral drugs have also been detected in the genes coding for transmembrane proteins. These findings raise concern for the possible human health risk presented by viruses with these genetic properties and highlight the need for increased efforts to monitor the evolution of A/H5N1 viruses across the African continent. They further stress how imperative it is to implement sustainable control strategies to improve animal and public health at a global level

Spatio-temporal epidemiology of highly pathogenic avian influenza (H5N1) outbreaks in Nigeria, 2006-2008

From 2006 to 2008, outbreaks of highly pathogenic avian influenza A (HPAI) virus of the H5N1 subtype occurred among poultry in Nigeria. We described the spatio-temporal patterns of the HPAI H5N1 outbreaks in Nigeria. Data of suspected and laboratory confirmed outbreaks maintained at the National Veterinary Research Institute Vom was analyzed using descriptive and exploratory analyses, GIS mapping, global and local spatial statistical analyses using the Cuzick-Edwards' (C-E) test and SaTScan Space-Time Scan Statistic. A total of 1654 suspected outbreaks were reported from 32 of the 36 States and the Federal Capital Territory (FCT), 299 were confirmed HPAI H5N1 positive from 27 states and FCT. The outbreaks occurred as three distinct epidemic waves with peak periods of January-March mainly in the North-West, North-Central and North-East regions during 2006 and 2007 and July-September in the South-West and South-South regions in 2007. Three spatio-temporal clusters were identified extending across States and international borders, consistent with disease transmission occurring through local and long-distance spread. This calls for enhanced strategies by the states and regional authorities to improve surveillance, prevention and control measures at the states, national and international levels

Surveillance for African swine fever in Nigeria, 2006-2009

African swine fever (ASF) has had significant economic and social impact in Nigeria since 1997. However, there has been no effective national response to bring it under control. In this report, we confirm that ASF is still prevalent and widespread in Nigeria. Results from both serosurveillance and virological analyses indicated that ASF is present in most of the agro-ecological zones of the country. Nine per cent (9%) of serum samples and 48% of tissue samples were positive for ASF virus antibody and genome, respectively. Areas with high pig-related activities (marketing, consumption and farming) have higher prevalences compared with areas with less pig activities. Farm-gate buyers, marketing systems and transport of untested pigs within the country assist with the circulation of the virus. Only by putting in place a comprehensive routine surveillance and testing system, reorganizing the market and transportation systems for pigs, implementing on-farm bio-security protocols and considering the option of compensation will it be possible to achieve a significant reduction in ASF prevalence in Nigeria. ©2010 Blackwell Verlag GmbH

Highly pathogenic avian influenza virus subtype H5N1 in Africa: a comprehensive phylogenetic analysis and molecular characterization of isolates.

Highly pathogenic avian influenza virus A/H5N1 was first officially reported in Africa in early 2006. Since the first outbreak in Nigeria, this virus spread rapidly to other African countries. From its emergence to early 2008, 11 African countries experienced A/H5N1 outbreaks in poultry and human cases were also reported in three of these countries. At present, little is known of the epidemiology and molecular evolution of A/H5N1 viruses in Africa. We have generated 494 full gene sequences from 67 African isolates and applied molecular analysis tools to a total of 1,152 A/H5N1 sequences obtained from viruses isolated in Africa, Europe and the Middle East between 2006 and early 2008. Detailed phylogenetic analyses of the 8 gene viral segments confirmed that 3 distinct sublineages were introduced, which have persisted and spread across the continent over this 2-year period. Additionally, our molecular epidemiological studies highlighted the association between genetic clustering and area of origin in a majority of cases. Molecular signatures unique to strains isolated in selected areas also gave us a clearer picture of the spread of A/H5N1 viruses across the continent. Mutations described as typical of human influenza viruses in the genes coding for internal proteins or associated with host adaptation and increased resistance to antiviral drugs have also been detected in the genes coding for transmembrane proteins. These findings raise concern for the possible human health risk presented by viruses with these genetic properties and highlight the need for increased efforts to monitor the evolution of A/H5N1 viruses across the African continent. They further stress how imperative it is to implement sustainable control strategies to improve animal and public health at a global level