Rotavirus (RV) and norovirus (NoV) are considered the most common causes of viral gastroenteritis in children. In this study, the prevalence of RV and NoV infection in 55 children with diarrhea from the rural community Akinlalu in Southwestern Nigeria was investigated using real‐time PCR assays. The RV and NoV strains were genotyped by PCR and/or sequencing. RV and NoV infections occurred with a prevalence of 34.5% and 25.5% respectively, with predominance in children <1 year. Most infections occurred during the dry season with increasing prevalence of RV as the dry season progressed (October–January). Infections with RV VP6 subgroup (SG) II were more prevalent (27.3%) than SGI (7.3%). Similarly, NoV genogroup II infections were more common (23.6%) than genogroup I (1.8%). Five children out of 55 (9.1%) were co‐infected with both RV and NoV. Notably, G12P[8] was the predominant RV strain (36.8%, n = 7), observed for the first time in Nigeria. The VP7 gene of the G12 strains clustered within lineage III, sharing high nucleotide identity with each other (>99%) indicating introduction in Nigeria from a single donor. Furthermore, a putative novel genotype within genogroup I NoV was detected, which till date has only been reported once in humans. To conclude, a high prevalence of the emerging G12P[8] RV strain was observed for the first time in Nigeria, as well as a putative novel NoV genotype in humans. These results provide new information which can be important for future vaccine evaluations and possible introduction in Nigeria. J. Med. Virol. 84:1489–1496, 2012. © 2012 Wiley Periodicals, Inc.

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BackgroundThe need to investigate the contribution of non-polio enteroviruses to acute flaccid paralysis (AFP) cannot be over emphasized as we move towards a poliovirus free world. Hence, we aim to identify non-polio enteroviruses recovered from the faeces of children diagnosed with AFP in Nigeria.MethodsNinety-six isolates, (95 unidentified and one previously confirmed Sabin poliovirus 3) recovered on RD cell culture from the stool of children <15 years old diagnosed with AFP in 2014 were analyzed. All isolates were subjected to RNA extraction, cDNA synthesis and three different PCR reactions (one panenterovirus 5′-UTR and two different VP1 amplification assays). VP1 amplicons were then sequenced and isolates identified.Results92.71% (89/96) of the isolates were detected by at least one of the three assays as an enterovirus. Precisely, 79.17% (76/96), 6.25% (6/96), 7.30% (7/96) and 7.30% (7/96) of the isolates were positive for both, positive and negative, negative and positive, as well as negative for both the 5′-UTR and VP1 assays, respectively. In this study, sixty-nine (69) of the 83 VP1 amplicons sequenced were identified as 27 different enterovirus types. The most commonly detected were CV-B3 (10 isolates) and EV-B75 (5 isolates). Specifically, one, twenty-four and two of the enterovirus types identified in this study belong to EV-A, EV-B and EV-C respectively.ConclusionsThis study reports the circulating strains of 27 non-polio enterovirus types in Nigerian children with AFP in 2014 and Nigerian strains of CV-B2, CV-B4, E17, EV-B80, EV-B73, EV-B97, EV-B93, EV-C99 and EV-A120 were reported for the first time. Furthermore, it shows that being positive for the 5′-UTR assay should not be the basis for subjecting isolates to the VP1 assays.

BackgroundTransfusion associated Hepatitis B virus (TAHBV) continues to be a major problem despite mandatory screening for Hepatitis B surface Antigen (HBsAg). Presence of HBsAg is the common method for detecting hepatitis B infection. Unfortunately, this marker is not detected during the window period of the infection. Nigeria being a developing country cannot afford DNA testing of all collected units of blood which serve as the only possibility of achieving zero risk of transfusion associated HBV. Five different serological makers of hepatitis B virus (HBV) infection were therefore assessed to evaluate the reliability of using HBsAg marker alone in diagnosis of HBV infection among blood donors and to detect the serological evidence of the infection at the window period. This will preclude the possibility of transmitting hepatitis B through transfusion of Hepatitis B surface antigen (HBsAg) negative blood in Nigeria.MethodsBetween July and August 2009, 92 blood donors were enrolled for the study. The prevalence of 5 different markers of Hepatitis B virus infection was detected using Enzyme Linked Immunosorbent Assay (ELISA). Demographic factors were assessed during the study.ResultsHBsAg and its antibody (anti-HBs) was detected in 18 (19.6%) and 14(15.2%) of the 92 blood donors respectively. Anti-HBc IgM was found in 12(13.0%) of the 92 blood donors while Hepatitis B envelope antigen (HBeAg) and its antibody (anti-HBe) were detected in 4(8.9%) and 12(26.7%) respectively from 45 donors sampled. HBeAg is a marker of high infectivity and appears after HBsAg. At least one serological marker was detected in 30(32.6%) of the blood donors. Five (5.4%) of the 92 donors had anti-HBc IgM as the only serological evidence of hepatitis B virus infection.ConclusionsThe result of this study shows that five donors have anti-HBcIgM as the only serological evidence of HBV infection. Inclusion of anti-HBcIgM in routine screening of blood donors in Nigeria should be encouraged. This is the first study to assess anti-HBcIgM in the country.

Nigeria having approximately 50 000 Rotavirus A (RVA) deaths annually is yet to introduce RVA vaccine into routine national immunization; therefore surveillance of RVA strains circulating before vaccine introduction is essential in evaluating impact of the intervention. Stool samples and sociodemographic data of diarrhoeic children, <5 years were collected between August 2012 and December 2013. While a high prevalence of RVA infection (47.6%; 49/103) was observed by quantitative reverse transcription real time PCR, only 25% (26/103) had high RVA genome concentrations and were antigen positive. G and P types were obtained for 31 and 37 samples respectively. G12P[8] strains were predominant (30.6%; 16/31); Other genotypes found included G9, G3, G2 and P[4], P[6], P[8]. A G12 + G2/P[8] + P[6] mixed infection was detected. The P[8] genotype showed divergence with strains distributed in lineage III and IV. Compared to the vaccines, changes in antigenic sites of VP8* and VP7 were found. The finding of the G2P[6] genotype combination and emergence of G12 strains support observations in most of the recent RVA studies from Africa. P[6] is common in many African countries, in contrast to countries in Europe and the Americas. In conclusion, this study shows the circulation of other RVA genotypes compared to the common RVA genotypes in Nigeria. PCR results should be interpreted with caution to avoid significant bias from samples with low RVA genome concentrations. These findings provide important information on the detection and molecular epidemiology of RVA prior to vaccination and contribute as a baseline for future evaluations after possible vaccine introduction.

Hepatitis B virus (HBV) infection is endemic in sub-Saharan Africa with a range of 8 to 20% prevalence of chronic carriers. Most HBV infections occur early in life by perinatal transmission from the mother to her newborn baby, and horizontal transmission from child to child resulting from blood contact. This study was therefore carried out to assess the prevalence of Hepatitis B virus surface antigenemia (HBsAg) in children born in Ilesha, Osun State, Southwestern Nigeria. A total of 144 children at age range 21 days to 13 years were tested for hepatitis B surface antigen (HBsAg) in Ilesha using Bio-Rad Monolisa HBsAg Ultra kit [enzyme-linked immunosorbent assay (ELISA), ELISA method]. Twenty (13.9%) children were seropositive for HBsAg. The age bracket 1-5 years had the highest number of children and the highest number of HBsAg positive cases (15.8%). Female children had a higher HBsAg antigenemia of 15.4% compared to 12.7% for the male children. High prevalence of hepatitis B surface antigen was found among the children. Focus should be re-intensified on childhood vaccination and information dissemination on the risk and mode of transmission of HBV. Women especially, should be educated on HBV to prevent Mother-to-child transmission (MTCT) of the infection.

As the global effort to eradicate hepatitis B continues, immune escape mutations (IEMs) and drug resistance mutations (DRMs) affecting its diagnosis, treatment, and prevention are compromising this goal. However, knowledge about the prevalence and circulation of these mutations in Nigeria is scarce. Serum samples (n = 199) from apparently healthy prospective blood donors, pregnant women, and individuals presenting with fever in southwestern Nigeria were analyzed for the presence of IEMs and DRMs by means of nested PCR in the HBV S (HBs) and HBV polymerase (Pol) genes, followed by phylogenetic and mutational analyses. In total, 25.1% (n = 50/199) of samples were positive for HBV, as measured by PCR. In 41 samples (20.6%), both fragments could be amplified, whereas the HBs gene and the Pol gene fragment alone were detected in 0.5% (n = 1/199) and 4% (n = 8/199) of samples, respectively. Sequences were successfully obtained for all 42 HBs gene fragments but for only 31/49 Pol gene fragments (totaling 73 sequences from 44 individuals). All sequences were identified as HBV genotype E. IEMs were present in 18.2% (n = 8/44) of the sequences of HBV-positive individuals with available sequences. IEM Q129H was detected in eight out of the 44 (18.2%) HBV isolates sequenced in this study; however, no DRMs were observed. This study confirms the circulation of HBV IEMs and reports the presence of Q129H IEM for the first time in Nigeria. Intensified research on the dynamics of IEM is necessary in order to enhance the elimination of HBV.

Blood transfusion service centers in Nigeria screen donated blood for markers of HIV infection using antibody- (Ab) based rapid test and in some centers, positives are re-tested using Ab-based ELISA. Paucity of data exists on p24 antigen prevalence among HIV Ab-negative donors in Nigeria. This study aims at detecting HIV p24 antigen among prospective blood donors in Osun State, Nigeria. Prospective blood donors negative for HIV antibodies using Determine test kit were re-tested using BIORAD GENSCREEN Ultra Ag-Ab ELISA kit, a fourth-generation ELISA kit that detects HIV antibodies/p24 antigen. Of the 169 HIV Ab-negative prospective donors, 10 (5.9%) were positive for HIV p24 antigen and 70% (7/10) of them were in the age range 18-30 years. Results of this study show that blood transfusion is still one of the major routes of HIV transmission in Nigeria and a higher proportion is among youth. Inclusion of p24 antigen testing into the blood donor screening will help reduce transfusion associated HIV in Nigeria if Nucleic Acid Testing (NAT) of all blood donor samples is not affordable; also, HIV enlightenment programs tailored toward youth may help reduce this rate among donors since more young people donate blood in low/middle-income countries than in high-income countries.