Genomic characterization of human rotavirus G8 strains from the African rotavirus network: relationship to animal rotaviruses.

Global rotavirus surveillance has led to the detection of many unusual human rotavirus (HRV) genotypes. During 1996-2004 surveillance within the African Rotavirus Network (ARN), six P[8],G8 and two P[6],G8 human rotavirus strains were identified. Gene fragments (RT-PCR amplicons) of all 11-gene segments of these G8 strains were sequenced in order to elucidate their genetic and evolutionary relationships. Phylogenetic and sequence analyses of each gene segment revealed high similarities (88-100% nt and 91-100% aa) for all segments except for gene 4 encoding VP4 proteins P[8] and P[6]. For most strains, almost all of the genes of the ARN strains other than neutralizing antigens are related to typical human strains of Wa genogroup. The VP7, NSP2, and NSP5 genes were closely related to cognate genes of animal strains (83-99% and 97-99% aa identity). This study suggests that the ARN G8 strains might have arisen through VP7 or VP4 gene reassortment events since most of the other gene segments resemble those of common human rotaviruses. However, VP7, NSP2 (likely), and NSP5 (likely) genes are derived potentially from animals consistent with a zoonotic introduction. Although these findings help elucidate rotavirus evolution, sequence studies of cognate animal rotavirus genes are needed to conclusively determine the specific origin of those genes relative to both human and animal rotavirus strains.

Rotavirus diarrhoea hospitalizations among children under 5 years of age in Nigeria, 2011-2016.

BACKGROUND: The high burden of rotavirus acute gastroenteritis (AGE) is well documented among children under 5 years of age, with the majority of mortality occurring in developing countries. Nigeria ranked second worldwide in the number of rotavirus deaths in 2013. As Nigeria plans to introduce rotavirus vaccine soon, a pre-vaccine documentation of rotavirus disease burden is necessary to determine vaccine impact. METHODS: Routine rotavirus surveillance was conducted during 2011-2016 in 3 sentinel sites in Nigeria using the standard WHO protocol. Children under 5 years of age hospitalized for acute gastroenteritis were enrolled and demographic, clinical and outcome data were collected. A stool sample was subsequently obtained and tested for human rotavirus antigen using the Enzyme-linked immunosorbent assay (ELISA). RESULTS: 2694 children with acute gastroenteritis were enrolled during January 2011 to December 2016; of these, 1242 (46%) tested positive for rotavirus. Among the rotavirus positive cases, 66% and 94% were younger than 12 months and 24 months respectively. Marked peaks in rotavirus positivity were seen in January of each year. Vomiting, and use of oral and intravenous fluids occurred more often in rotavirus positive cases as compared to rotavirus negative cases. CONCLUSION: The high prevalence of rotavirus disease highlights the need for urgent introduction of rotavirus vaccine in Nigeria. Additionally, this study provides pre-vaccine introduction disease-burden data that will serve as a baseline for rotavirus vaccine impact-assessment once vaccine has been introduced in the national immunization program.

Prevalence of enteric infections among hospitalized patients in two referral hospitals in Ghana.

BACKGROUND: Diarrhea is an important cause of morbidity and mortality worldwide. In Africa and Ghana in particular, it is estimated to contribute directly to 19 and 25% of pediatric mortality among children under 5 years, respectively. METHODS: Surveillance for hospitalized acute diarrheal illness was initiated in November 2010 through October 2012 in a referral hospital in southern Ghana, and a teaching hospital in northern Ghana. Consenting hospitalized patients who met a standardized case definition for acute diarrheal illness provided demographic and epidemiologic data. Stool samples were collected and tested by culture for bacteria and by enzyme immunoassays for a panel of viruses and parasites. RESULTS: A total of 429 patients were enrolled; 216 (50.3%) were under 5 years, and 221 (51.5%) were females. Stool samples were received from 153 patients. Culture isolates included Shigella sp., Salmonella spp., Plesiomonas sp. and Vibrio cholerae. Of 147 samples tested for viruses, 41 (27.9%) were positive for rotaviruses, 11 (7.5%) for astroviruses, 10 (6.8%) for noroviruses, and 8 (5.4%) for adenoviruses. Of 116 samples tested for parasitic infections; 4 (3.4%) were positive for Cryptosporidium sp. and 3 (2.6%) for Giardia lamblia. Of the enrolled patients, 78.8% had taken antibiotics prior to sample collection. CONCLUSIONS: Diarrheal pathogens were identified across all ages, however, predominantly (81%) in the children under 5 years of age. This study also detected high antibiotic use which has the potential of increasing antibiotic resistance. The most common enteric pathogen detected (49.4%) was rotavirus.

Conformation and immunogenicity of engineered repeating segment of the circumsporozoite surface protein of Plasmodium falciparum.

Peptide vaccines based on units of the immunodominant tetrapeptide repeats, Asn-Ala-Asn-Pro and Asn-Val-Asp-Pro, of the circumsporozoite surface protein of the parasite Plasmodium falciparum are presently being developed as potential malaria vaccines. The N-terminal fusion of a hydrophobic protein to units of the tetrapeptide repeat affected the immunogenicity and conformational stability of the peptide, and also induced a secondary structure in the peptide. Peptide antigenicity, as well as conformational stability, was significantly increased.

Ultrastructural changes in animal fat associated lipoid pneumonia: report of two cases.

Traditional or cultural practices in different parts of the world where oils are used continue to produce lipoid pneumonia. We report the ultrastructural findings and observations in animal fat associated lipoid pneumonia from two children following a cultural practice of forced feeding with animal fat (ghee). Clinical findings showed an acute or chronic chest infection which failed to respond to anti-microbial therapy. X-ray and chest CT scan revealed collapse/consolidations of the right middle and left lower lobes. Histology and electron microscopy revealed thickening and destruction of the alveolar septa, filling of alveolar spaces with red blood cells and macrophage which contained both primary and secondary lysosomes. The alveolar walls contained mostly type II pneumocyte with most of them surrounded by thickened basement membranes with only a small portion of their surfaces exposed directly to the alveolar space where it showed numerous microvilli.

Pattern of breast diseases in Accra: review of mammography reports.

OBJECTIVES: To document the mammographic patterns in females seeking medical attention in Accra. DESIGN: An analytic retrospective study was conducted using data extracted from mammography request forms and corresponding radiological reports of 180 females. SETTING: The radiology departments of Korle-Bu Teaching Hospital the Trust Hospital and Medical Imaging Ghana all located in Accra. RESULTS: One hundred and eighty radiologic request forms for mammographic evaluations and their corresponding reports from the study period were reviewed. The mean age of the study population was 48.7 years (SD=10.0), and the median age group was the 41-50 group. There were more screening mammography evaluations (115 examinations) than diagnostic mammography evaluations (65 examinations). Most of the cases diagnosed as breast cancer were in the age group 41-50 years. Benign lesions were commoner than cancer (55 and 16 cases respectively). The commonest presenting complaint was of pain. CONCLUSION: The larger number of screening mammographic evaluations conducted for asymptomatic females during the study period, as compared to diagnostic mammographic evaluations for symptomatic females, suggests that educational programs on early breast cancer detection are having a positive impact on the target population. The observation that 22.8% of lesions had features suggestive of breast cancer in the study is significantly high to also warrant intensification of the existing awareness programs. As non-specific masses were the most common radiographically observed lesions, hospitals equipped with sonography and biopsy facilities that compliment their mammography are better suited for thorough breast disease evaluation.

A chronic toxicity study of the ground root bark of Capparis erythrocarpus (Cappareceae) in male Sprague-Dawley rats.

The safety evaluation of Capparis erythrocarpus (CE) on chronic administration at 18 and 180 mg kg(-1) body weight for 6 months was investigated in male Sprague-Dawley rats. The effects of CE on certain serum biochemical, haematological, urine and histopathological determinations were used as indices of organ specific toxicity. Also the effects of CE on rat blood clotting time and pentobarbital-induced sleeping time were determined. Results indicate that CE had no effect on urine, haematological and serum biochemical indices at termination of treatment with the exception of serum ALT level which was significantly (p < 0.05) attenuated in a dose-dependent fashion (21-35%). There were also no differences in blood clotting time and pentobarbital-induced sleeping time between CE-treated and control animals. Histopathological studies showed that CE did not adversely affect the morphology of the liver, kidney and heart tissues. However, lungs of CE-treated animals showed slight but insignificant inflammatory response in alveolar areas and Clara cell hyperplasia without the thickening of alveolar septa and bronchiolar epithelial wall. Organ weights were not adversely affected by CE treatment. There were significant (p < 0.05) changes in weight of CE-treated animals with duration of treatment compared to control. These results suggest that there is no organ specific toxicity associated with chronic administration of CE in rats and its ability to reduce body weight may be useful for slimming in obese persons.

Human G9P[8] rotavirus strains circulating in Cameroon, 1999-2000: Genetic relationships with other G9 strains and detection of a new G9 subtype.

Group A rotaviruses (RV-A) are the leading cause of viral gastroenteritis in children worldwide and genotype G9P[8] is one of the five most common genotypes detected in humans. In order to gain insight into the degree of genetic variability of G9P[8] strains circulating in Cameroon, stool samples were collected during the 1999-2000 rotavirus season in two different geographic regions in Cameroon (Southwest and Western Regions). By RT-PCR, 15 G9P[8] strains (15/89=16.8%) were identified whose genomic configurations was subsequently determined by complete or partial gene sequencing. In general, all Cameroonian G9 strains clustered into current globally-spread sublineages of the VP7 gene and displayed 86.6-100% nucleotide identity amongst themselves and 81.2-99.5% nucleotide identity with global G9 strains. The full genome classification of all Cameroonian strains was G9-P[8]-I1-R1-C1-M1-A1-N1-T1-E1-H1 but phylogenetic analysis of each gene revealed that the strains were spread across 4 or more distinct lineages. An unusual strain, RVA/Human-wt/CMR/6788/1999/G9P[8], which shared the genomic constellation of other Cameroonian G9P[8] strains, contained a novel G9 subtype which diverged significantly (18.8% nucleotide and 19% amino acid distance) from previously described G9 strains. Nucleotide and amino acid alignments revealed that the 3' end of this gene is highly divergent from other G9 VP7 genes suggesting that it arose through extensive accumulation of point mutations. The results of this study demonstrate that diverse G9 strains circulated in Cameroon during 1999-2000.

Genomic characterization of human rotavirus G10 strains from the African Rotavirus Network: relationship to animal rotaviruses.

Global rotavirus surveillance has led to the detection of many unusual human rotavirus (HRV) genotypes. The aim of this study was to elucidate the genetic and evolutionary relationships of short fragments of all 11 gene segments of G10 HRV strains identified in West Africa through the African Rotavirus Network (ARN) system. During 1998-2004 surveillance within the ARN, we identified 5 G10 P[8] HRV strains. Fragments of all 11 gene segments of these G10 strains were sequenced. Phylogenetic and sequence analyses of each gene segment revealed high nucleotide similarities amongst the ARN strains (97-100%) except in the case of the VP1(85-96%) and NSP2 genes (87.8-99.7%) where some strains were divergent. All genes of the ARN strains were classified as Wa-like (genotype 1) with the exception of their VP7 gene of all strains (genotype G10) and the VP6 gene of a single strain, 6755/2002/ARN (DS-1 like, genotype 2). While classified as Wa-like, the NSP2 genes of four of the ARN strains occupied a distinct sub-lineage related to simian strain Tuch, while the NSP2 of strain 6755/2002/ARN and NSP5 genes of all strains were closely related to the cognate genes of both human and animal strains belonging to the Wa-like genogroup. Although these findings help to elucidate the evolution of ARN G10 strains, additional sequence studies of cognate animal rotavirus genes are needed to determine irrefutably the specific origin of those genes relative to both human and animal rotavirus strains.

Orofacial tumours and tumour-like lesions in Ghana: a 6-year prospective study.

A total of 182 patients with orofacial tumours and tumour-like lesions who attended the oral and maxillofacial surgical department of the Korle-Bu Teaching Hospital, Accra, were studied from 1 January 1998 to 31 December 2003. Both malignant and benign tumours were recorded and were more common among men (99/182, 54%) in whom they were seen most often between the ages of 41 and 70 years. Among female patients they were more common in the 11-20 year age group. The mandible, maxilla, and palate were most often affected. A total of 108 tumours were diagnosed as malignant (59%), 27 (15%) as benign odontogenic tumours, and 47 (26%) as benign non-odontogenic and tumour-like lesions. Malignant tumours were usually detected in men between the ages of 41 and 70 years (43% of all men); whilst benign tumours were evenly distributed between the sexes with more among girls in the 11-20 year age group. The most common malignant tumours were squamous cell carcinoma (SCC), (69/108, 64%) and lymphomas (18/108, 17%). The predominant benign odontogenic and non-odontogenic tumours were ameloblastoma and fibro-osseous lesions, respectively. The usual method of treatment was resection (58/182, 32%).

Detection of group a rotavirus strains circulating in calves in Tunisia.

Faecal samples were collected from 89 dairy calves to determine the prevalence of rotavirus infection in Tunisia and the genomic diversity of bovine rotavirus strains. After screening of all faecal samples by enzyme-linked immunosorbent assay, rotavirus strains were analysed by RNA polyacrylamide gel electrophoresis and characterized antigenically by monoclonal antibodies to the VP6 subgroup. The VP7 genotype was determined by nested RT-PCR. Of the 89 calves tested, 27 (30%) were positive for rotavirus antigen. Four different long electrophoretypes were identified. All VP6 typeable strains carried the subgroup I specificity. G8 genotype was the most prevalent, but G6 and mixed strains G(6 + 8) were also detected.

The synthesis, cloning and expression of a repeating segment of the circumsporozoite surface protein of Plasmodium falciparum.

Repeats of the tetrapeptide (NANP) of the circumsporozoite protein of P. falciparum have been found to be immunogenic and possibly may act as vaccines against malaria infection. The DNA duplex encoding for eight of the (NANP) repeating unit and two of the (NVDP) unit have been synthesized, cloned and expressed in E. coli as a fused protein. The recombinant protein was shown to be immunogenic and to have the antigenic activity of the circumsporozoite.

Detection and characterization of human rotavirus among children with diarrhoea in Botswana.

This study reports the detection, for the first time, of human rotavirus in stools of children and the molecular characterization of isolated circulating strains in Botswana. We collected 249 stool samples between 1999 and 2001 from children with diarrhoea in three health districts of Botswana and examined them for the presence of rotavirus antigens and particles. Group A rotavirus antigen was detected in 43 of 249 (17%) of the samples tested by enzyme-linked immunosorbent assay. Of the 43 children shedding rotaviruses, 37 (86%) were infants < or =2 years of age. The presence of rotavirus particles was also confirmed by direct electron microscopy. The characteristic 11 segments of the double-stranded RNA mobility pattern of rotavirus were demonstrated by polyacrylamide electrophoresis in 20 of 43 (47%) of the rotavirus-positive samples. The predominant electrophoretic pattern detected was the long (L) electrophoretype 14 of 20 (70%) followed by the short (S) electrophoretype five of 20 (25%). One strain had a mixed (L/S) pattern. Of the 26 samples subjected to subgrouping by enzyme immuno assay, eight were typed as subgroup-II specific and seven were subgroup I. The predominant VP7 genotypes detected were G1 (59%). Two mixed strains of G1 + G3 (5%) and G1 + G2 (5%) were also detected. VP4 genotypes in circulation were: P[4] (5%), P[6] (33%) and P[8] (33%). Mixed P-types P[4 + 6] (5%) and P[6 + 8] (18%) were also detected. Rotavirus strains G1 P[8] and GI P[6 + 8] were the most common cause of diarrhoea in our study area.

Enteric pathogens in severe forms of acute gastroenteritis in Ghanaian children.

Diarrheal disease is the major cause of childhood morbidity in developing countries. Although malnutrition is known as a risk factor for severe gastroenteritis, the role of enteric pathogens in the clinical severity is unclear. The present study was conducted in well nourished Ghanaian preschool children during a 3 month period of the rainy season to assess the relationship between enteric pathogens and severe gastroenteritis. Two hundred and twenty-five children with acute gastroenteritis and 64 age-matched control children were prospectively examined for the severity of dehydration and enteric pathogens in their stools. Of the 225 children with gastroenteritis, 69.8% (157/225) had mild dehydration and 30.2% (68/225) had severe dehydration. Bacteria were similarly isolated in stool samples from children with mild and severe dehydration and controls. Rotavirus accounted for 20.6% of children with severe dehydration and was more often isolated in stools from patients with severe dehydration than those from controls. Furthermore, the mixed infections associated with rotavirus and bacteria were more often found in patients with severe dehydration than those with mild dehydration or controls. Parasites were similarly found at low incidences among the three groups. The present study implied that rotavirus was more responsible for severe gastroenteritis than bacteria or parasites. However, factors other than enteric pathogens must be sought in a considerable number of severe cases. A large scale study throughout a year is recommended to obtain more precise information that would reflect the seasonal variation of rotavirus infections.

Seasonality of rotavirus infection in Ghana.

Human rotavirus (HRV) infection and its seasonal distribution was studied over a 12-month period in Ghana. A total of 561 stool samples, 447 diarrhoea stools and 114 non-diarrhoea stools (controls), were obtained from children attending three polyclinics in Accra. Rotavirus was detected during 10 of the 12 months and showed a seasonal trend. It was high during the relatively cool dry months and low during the wet season. Peaks of infection were in February (26.2%) and September (24.5%). HRV was detected in 67 of 447 of the diarrhoea stools (15.0%) and in eight of 114 controls (7.0%). The HRV isolation rate was highest (20.2%) in the under-18-months age group. The RNA electropherotype of the HRV isolates was predominantly (83.6%) of the long type. Non-group A HRV was detected in 14.9% of the HRV-positive samples.

Prevalence of unusual human rotavirus strains in Ghanaian children.

Sixty-seven rotavirus-positive fecal samples, collected between January and April 1999, from children with diarrhea in the Upper East Region of Ghana were examined for rotavirus VP7 and VP4 types. Sufficient viral RNA could be obtained from 46 (68.7%) of the samples and all the isolates had short electrophoretic pattern and typed as subgroup I rotaviruses by subgroup ELISA. Three rotavirus strains with G8 specificity were identified for the first time in Ghana. G and P typing by PCR identified two distinct strains, P[6]G2 (50%) and P[6]G8 (4.3%). Eighty-two percent of the isolates (n = 38) were of the "putative" neonatal P[6] genotype. Two of these G8 isolates carried the VP4 P[6] genotype whereas the third could not be assigned a P type. Mixed infections of G1, G2, G3 and G8 were detected amongst the stool samples. The presence of these unusual strains, especially the high incidence of G2 rotavirus strains in Ghana, reinforces the need to put in place a surveillance system for the detection of new and exotic rotavirus strains, that will provide information on the spread of these strains in West Africa as well as useful data for the formulation of the next generation of rotavirus vaccines.

Impact of permethrin impregnated bednets on child mortality in Kassena-Nankana district, Ghana: a randomized controlled trial.

A community-based randomized, controlled trial of permethrin impregnated bednets was carried out in a rural area of northern Ghana, between July 1993 and June 1995, to assess the impact on the mortality of young children in an area of intense transmission of malaria and no tradition of bednet use. The district around Navrongo was divided into 96 geographical areas and in 48 randomly selected areas households were provided with permethrin impregnated bednets which were re-impregnated every 6 months. A longitudinal demographic surveillance system was used to record births, deaths and migrations, to evaluate compliance and to measure child mortality. The use of permethrin impregnated bednets was associated with 17% reduction in all-cause mortality in children aged 6 months to 4 years (RR = 0.83; 95% CI 0.69-1.00; P = 0.05). The reduction in mortality was confined to children aged 2 years of younger, and was greater in July-December, during the wet season and immediately after (RR = 0.79; 95% CI 0.63-1.00), a period when malaria mortality is likely to be increased, than in the dry season (RR = 0.92, 95% CI 0.73-1.14). The ready acceptance of bednets, the high level of compliance in their use and the subsequent impact on all-cause mortality in this study has important implications for programmes to control malaria in sub-Saharan Africa.

Rotavirus G and P genotypes in rural Ghana.

An epidemiological study of rotavirus infection was conducted on specimens collected from patients with gastroenteritis and domiciled in the rural Upper Eastern Region of Ghana during 1998. Fifty isolates, randomly selected from 165 human group A rotavirus-positive samples, were G and P characterized by a reverse transcription (RT)-PCR assay using a seminested multiplex method. Rotaviruses of the G3 genotype were found to be the predominant strain (78%), followed by G2 (14%) and G1 (2%). Mixed infections, as shown by combinations of G3 and G2 (4%) and G3 and G1 (2%), were also observed. P typing showed P[4] (72.34%) to be the prevalent strain, followed by P[6] (21.3%), P[8] (2.13%), and a combination of P[4] and P[6] (4.3%).