Rabies Virus Neutralizing Antibodies in Unvaccinated Rabies Occupational Risk Groups in Niger State, Nigeria.

Aims: To determine the presence of rabies virus neutralizing antibodies (rVNA) as well the potency of the rVNA in rabies occupational risk humans in Niger State of Nigeria. Study Design: Cross-sectional study. Place and Duration: Research was conducted at the Department of Veterinary Public Health, Ahmadu Bello University, Zaria, Nigeria and Rabies Unit, Centers for Disease Control and Prevention, CDC, Atlanta, USA, between May, 2012 and March, 2013 Materials and Methods: A total of 185 human volunteers were recruited from rabies risk occupational groups who filled a structured questionnaire on their previous bite history and vaccination status, between May and July, 2012. A 2 ml each of blood from volunteers was collected and centrifuged at 3000 rpm for 10 minutes and sera separated into pre-labeled vacutainers. Standard Rapid fluorescent focus inhibition test (RFFIT) was used to detect the presence of rVNA in the sera. Further end point titration of the rVNA positive human sera was conducted to determine the potency. Results: The results indicated that, detectable titre of rVNA was recorded in 16.4% (23 of 140) viable human sera screened. Although from the questionnaire survey, 21.7% (5 out of the 23 positives) responded to have been vaccinated over ten years prior. At least 3 of the respondents (1 dog butcher and 2 dog meat consumers) who responded not previously vaccinated had some neutralizing antibody titre range of 0.65 – 0.7 IU/ml which is above the minimum protective titre (0.5IU/ml) recommended by WHO. Similarly, 3 respondents (2 veterinarians and 1 animal health personnel) who responded to have been previously vaccinated (> 10 years earlier) yet had a high titre range of 0.5 – 5.4IU/ml. The highest specific rate for rVNA of 25% each was seen amongst the dog butchers and pet owners followed by hunters (20%) and dog meat consumers (14.8%). Up to 125 (67.6%) of the volunteers do consume dog meat with only 12 (9.6%) of them being dog butchers who source dogs for slaughter from households within and outside their territories. Conclusion: Although the WHO minimum protective titre of rVNA is 0.5 IU/ml, the presence of relatively high titres amongst these risk groups in this report is an indication of a serious public health threat. This study recommends the vaccination of rabies high risk groups and further screening of rabies occupational risk and non risk groups in the study area and Nigeria at large.

Rotavirus infection in four states in north-western Nigeria

Background: Rotaviruses are associated with 611;000 deaths worldwide and with 33;000 deaths in Nigeria in children 5 years of age annually. However; limited data exit on rotavirus (RV) infection in North-western Nigeria. This study surveyed RV infection in four states in Northwestern Nigeria. Methods: During July 2002 to July 2004; 1063 (869 diarrhoeic and 194 control) stool samples were collected from children 0.05). The highest RV burden was detected in children aged below six months. The infection occurred throughout the study period. The most common clinical features associated with RV were fever (71);vomiting (64.1) and a combination of fever and vomiting (48.2). Vomiting was strongly associated with RV (p 0.01). There was a statistically significant association between food type and rotavirus infection (p 0.05); with the highest prevalence occurring amongst children exclusively breast-fed. The majority of the RV positive samples revealed long electropherotypes and VP6 subgroup I + II specificity. Conclusion: Rotavirus was shown to be an important cause of diarrhoea in children 0-5 years of age in Northwestern Nigeria. An effective vaccine would therefore need to be administered at birth for children in the study area since there is no effective way to completely eliminate rotavirus infection other than vaccination. There is also a need for additional studies in Nigeria to provide data required to hasten vaccine introduction

Electropherotypes and Subgroups of Group A Rotaviruses Circulating among Diarrhoeic Children in Kano; Nigeria

Background: It is estimated that about 600?000 children die annually as a result of severe dehydrating diarrhea caused by rotaviruses. The virus is a double stranded RNA (dsRNA) virus with 11 segments. Group A rotaviruses show a characteristic 4-2-3-2 pattern following electrophoresis. The VP6 subgroups; I and II exist. This work was carried out to study the prevalence of rotavirus infection among children 0-5 years with diarrhea in Kano; and to determine the circulating subgroups and electropherotypes and of the rotavirus isolates. Methods: Two hundred and eighteen stool specimens from children 0-60 months (198 diarrheic and 20 non-diarrheic) were collected from different hospitals and health care centers in Kano and subjected to group A rotavirus enzyme linked immunosorbent assay (ELISA) to determine presence of group A rotavirus; subgroup ELISA to determine the VP6 subgroups and polyacrylamide gel electrophoresis (PAGE) to determine the electropherotypes present. Results: The long electropherotypes (47.05) of four variations dominated over the short electropherotype (17.64). About 11.76of the isolates were of mixed infection. Dominance of subgroup II (45) over subgroup I (25); and the presence of both subgroups I and II (10) and neither subgroup I nor II (15) was observed in this study. Conclusion: Information on the genomic diversity of the RNA electropherotypes in this region; Kano; is reported in this study