Rotavirus and bacterial diarrhoea among children in Ile-Ife, Nigeria: Burden, risk factors and seasonality

BACKGROUND

Diarrhoea is a leading cause of death among under-five children globally, with sub-Saharan Africa alone accounting for 1/3 episodes yearly. Viruses, bacteria and parasites may cause diarrhoea. Rotavirus is the most common viral aetiology of diarrhoea in children less than five years globally. In Nigeria, there is scarce data on the prevalence/importance, burden, clinical/risk factors and seasonality of rotavirus and bacteria and this study aims to determine the role of rotavirus and bacteria on diarrhoea cases in children less than five years in Ile-Ife, Nigeria.

METHODS

Socio-demographic data, environmental/risk factors and diarrhoiec stool samples were collected from children less than five years presenting with acute diarrhoea. Rotavirus was identified using ELISA. Bacteria pathogens were detected using cultural technique and typed using PCR. Diarrhoeagenic E. coli (DEC) isolates were subjected to antimicrobial susceptibility testing. Pathogen positive and negative samples were compared in terms of gender, age-group, seasonal distribution, and clinical/risk factors using chi-square with two-tailed significance. SPSS version 20.0.1 for Windows was used for statistical analysis.

RESULTS

At least one pathogen was detected from 63 (60.6%) children having gastroenteritis while 28 (44.4%) had multiple infections. Rotavirus was the most detected pathogen. Prevalence of rotavirus mono-infection was 22%, multiple infection with bacteria was 45%. Mono-infection prevalence of DEC, Shigella spp., and Salmonella spp. were 5.8% (6/104), 5.8% (6/104), and 2.9% (3/104) and co-infection with RVA were 23.1% (24/104), 21.2% (22/104) and 10.6% (11/104) respectively. All rotaviral infections were observed in the dry season. The pathotypes of DEC detected were STEC and EAEC. Parent earnings and mid-upper arm circumference measurement have statistical correlation with diarrhoea (p = 0.034; 0.035 respectively).

CONCLUSION

In this study, rotavirus was more prevalent than bacteria and occurred only in the dry season. Among bacteria aetiologies, DEC was the most common detected. Differences in seasonal peaks of rotavirus and DEC could be employed in diarrhoea management in Nigeria and other tropical countries to ensure optimal limited resources usage in preventing diarrhoea transmission and reducing indiscriminate use of antibiotics.

Serological patterns of hepatitis B virus infection among people living with HIV in Ibadan, Nigeria

Hepatitis B virus (HBV) is a leading cause of liver pathology, which has remained a serious public health challenge in spite of the availability of hepatitis B vaccine discovered about 40 years ago. People living with human immunodeficiency virus (PLHIV) are more at risk of hepatic problems as liver complications appear and progresses faster, owing to their immunocompromised status. This study seeks to determine HBV exposure, serological pattern, and HBV susceptibility among PLHIV. One hundred and fifty PLHIV were enrolled for the study. About 5 mL of blood was collected, processed, and tested for markers of hepatitis B virus: HBsAg, anti-HBs, HBeAg, anti-HBe, and anti-HBc. Twenty-eight (18.7%) had at least one serological marker while 122 (81.3%) tested negative to all the markers. The prevalence of HBsAg in this study was 8.7%, anti-HBs prevalence was 10%, while HBeAg was 2.7%, anti-HBe 6.0%, and anti-HBc 6.7%. Higher HBsAg, HBeAg, and anti-HBc prevalence were observed among the male participants with 13.9%, 5.6%, and 13.9%, respectively, while the female participants had more anti-HBs and anti-HBe of 1.8% and 6.1%, respectively. Age group 51-60 years had the highest prevalence of HBsAg (17.7%), HBeAg (11.8%), and anti-HBe (11.8%) while age group 31-40 years had the highest prevalence of anti-HBs (14.8%) and anti-HBe (9.8%). This study revealed the different serologic patterns of HBV infection among PLHIV and that susceptibility to HBV infection among PLHIV is high.

Viral gastroenteritis among children of 0-5 years in Nigeria: Characterization of the first Nigerian aichivirus, recombinant noroviruses and detection of a zoonotic astrovirus

BACKGROUND

Viruses are the leading cause of acute gastroenteritis in children worldwide. Understanding of the occurrence and genetic diversity of these viruses can help to prevent infections.

OBJECTIVES

The present study describes the presence, genetic diversity and possible recombination of five enteric viruses in children with gastroenteritis in Southwestern Nigeria.

STUDY DESIGN

From August 2012 to December 2013, stool samples and sociodemographic data of 103 diarrheic children <5 years were collected to detect and characterize rotavirus A, norovirus, human astrovirus, aichivirus and sapovirus using PCR techniques followed by sequencing and phylogenetic analyses.

RESULTS

At least one virus was identified in 58.3% (60/103) of the stool samples. Rotavirus, norovirus and astrovirus were detected in 39.8% (41/103), 10.7% (11/103), and 6.8% (7/103) respectively. Notably, aichivirus was detected for the first time in Nigeria (1/103; 0.97%). Sapovirus was not detected in the study. Co-infections with rotavirus were observed in eight samples either with norovirus or astrovirus or aichivirus. Phylogenetic analyses of different genome regions of norovirus positive samples provided indication for recombinant norovirus strains. A novel astrovirus strain closely related to canine astrovirus was identified and further characterized for the first time.

CONCLUSIONS

Viruses are the common cause of acute gastroenteritis in Nigerian infants with rotavirus as most frequently detected pathogen. New norovirus recombinants and a not yet detected zoonotic astrovirus were circulating in Southwestern Nigeria, providing new information about emerging and unusual strains of viruses causing diarrhea.

Non-polio enteroviruses in faeces of children diagnosed with acute flaccid paralysis in Nigeria

Background

The 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.

Methods

Ninety-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.

Results

92.71% (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.

Conclusions

This 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.

High prevalence of HIV p24 antigen among HIV antibody negative prospective blood donors in Ile-Ife, Nigeria

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.

Molecular epidemiology of rotavirus and norovirus in Ile-Ife, Nigeria: high prevalence of G12P[8] rotavirus strains and detection of a rare norovirus genotype

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.

The study of asymptomatic Plasmodium falciparum in humans infectedwith immunodeficiency virus in Ile-Ife, Nigeria

The study of the prevalence of asymptomatic <em>Plasmodium falciparum</em> in humans infected with immunodeficiency virus (HIV) was carried out in Ile-Ife, Osun State Nigeria. The aim of the study is to determine the prevalence of asymptomatic infection <em>P.falciparum</em> in HIV positive individuals and correlate it to age Parasitaemia and CD4 T cell count. Out of ninety three (93) HIV positive patients that participated in the study, 53 (58.8%) were females while 40 (41.4%) were males; 48 (52.4%) females and 35 (33.8%) males were positive for asymptomatic <em>P. falciparum</em> given a total number of 83 (86.6%). Twenty non-HIV patients were used as control samples: 9 (45%) were males and 11 (55%) were females. With 3.0 (33.3%) males and 5 (45.45%) females were positive with insignificant value of mean Parasitaemia of 125.0µl of blood. Age group 31-40 had the highest positive rate of 26 (32.2%) and age group 11-20 and above 60 had the least of positive rate. The correlation between age and both CD4 T cell count and Parasitaemia showed levels of significance less than 0.01 (P&lt;0.01) while the correlation between CD4 T cell and count and Parasitaemia showed no significant correlation, having P-value of P&gt;0.05. Comparing the males mean age, CD4 T cell count and Parasitaemia with that of females there was no level of significance P-value being greater than 0.05 (P&gt;0.05) each. In conclusion, the study showed that in asymptomatic P<em>lasmodium falciparum</em>, almost all the tested samples were positive which could be as a result of depletion in the immune level, hence there is need to always screen for <em>Plasmodium falciparum</em> whether in asymptomatic or symptomatic patients. The CD4 T cells count from the study can not be used for the detection or determination of the presence of malaria infection in HIV positive patients. The best method for malaria identification so far is still the staining method. There should not be discrimination when sampling the patient when investigations on HIV and malaria are to be carried out when both are infected.

Hepatitis B core IgM antibody (anti-HBcIgM) among hepatitis B surface antigen (HBsAg) negative blood donors in Nigeria

BACKGROUND

Transfusion 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.

METHODS

Between 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.

RESULTS

HBsAg 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.

CONCLUSIONS

The 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.