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Lassa Fever (LF) continues to be an endemic acute viral hemorrhagic fever (VHF) illness in Nigeria. Many suspected cases of LF infection have subsequently been confirmed negative and raises concerns as to what the diagnosis of such patients could be. Hence this study was to determine the causative agents of unconfirmed LF among initially suspected cases in South Western Nigeria. In this retrospective study, blood samples originally collected from 233 suspected cases of a LF outbreak response at Owo and Ose LGAs of Ondo State, were transported in triple level packaging and stored at -80°C. All samples were screened for LF IgM and IgG markers and LF PCR. Forty-five out of the stored plasma samples were randomly retrieved and analyzed for presence of IgM for seven other VHF viruses; Chikungunya (CHIK), West Nile (WN), Rift Valley fever (RVF), Yellow fever (YF), Dengue fever (DEN), Zika and Crimean-Congo hemorrhagic fever (CCHF). Out of 45 samples screened, 1 (2.2%) was positive for YF IgM antibody. The same sample was previously confirmed LF positive by PCR. This LF and YF co-infection was from a male, 23-year old individual. The presence of co-infections of LF and YF draw to limelight the need to be broad minded in exploring for the presence of other VHF viruses in outbreaks. Further studies are needed to decipher the diagnosis of LF suspected cases.

Zika virus (ZIKV) is one of the arboviruses implicated in febrile illness, microcephaly and other neurological disorders in babies whose mothers were infected during pregnancy. Information on ZIKV in Nigeria is limited. Hence, this study was aimed at investigating the seroprevalence of Zika virus among pregnant women in Lagos State. In a cross-sectional study, blood samples collected from 352 randomly selected pregnant women in four hospitals in Lagos State were separated and plasma analyzed using Zika virus IgG and IgM capture Enzyme-linked immunosorbent assay (Demeditec Diagnostics, Germany). The optical densities were read using Precision Microplate reader (Molecular devices) and cut-off calculated according to manufacturer’s guide. Parameters and symptoms such as history of fever, rashes on the body, exposure to mosquito were extracted from the questionnaire and analyzed. IgM seropositive samples were screened for ZIKV RNA on RT-qPCR. Out of 352 samples screened, 7(2.0%) and 5(1.4%) of the pregnant women tested positive for IgG and IgM respectively. None tested positive for both IgG and IgM markers. Statistical analysis showed that there is no significant relationship between the symptoms analyzed in this study at 95% Confidence interval except conjunctivitis. None of the ZIKV IgM seropositive samples tested positive for ZIKV RNA on RT-qPCR. The results show that there is evidence of exposure to Zika virus among the population studied in Lagos, Nigeria. Also, the low level seroprevalence of the virus in the population studied indicates that there is lack of herd immunity of Zika virus infection in Lagos, Nigeria.

Background: The current resurgence and transmission dynamics of Lassa fever (LF) within an endemic community in Nigeria calls for concern. Lassa fever virus is known to be transmitted from rodents to humans as well as from human to human. This study aims to compare the knowledge, attitude/practices and prevention of Community dwellers (CD) and Contacts of confirmed Lassa fever patients (CCP) with respect to LF in an endemic area in Nigeria. Methodology: This is a comparative cross-sectional study conducted between 2018 and 2019 during an outbreak of LF disease in Ondo State, Nigeria. A total of 250 consenting CD and 104 CCP were randomly selected to participate in this study. They were administered semi-structured questionnaires which were analysed using SPSSv23. Lassa fever disease causative agents, mode of transmission and prevention as well as actions on response to Lassa virus infections were assessed among respondents. Data were analysed and presented using descriptive statistics at 95% confidence interval and (p

Background: The world is currently experiencing a healthcare crisis caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Healthcare workers (HCWs) are at the forefront of controlling the spread of the disease; this response has resulted in a huge number of infections amongst HCWs and unfortunately some casualties. Infection prevention and control practices (IPC) are practical, proven methods that prevent avoidable harm to patients and protect health workers from contagious infection. This study was done to evaluate the effectiveness of IPC practices utilized in COVID-19 testing drive through facility in Lagos Nigeria. Method: The facility recruited 42 HCWs who were trained on IPC and use of Personal Protective Equipment (PPEs). Training on donning and doffing of PPEs, preparation of decontaminants and sample handling were done for relevant personnel. A daily log for monitoring COVID-19 symptoms was deployed to all HCWs; to help early detection of COVID-19 infection and prevent transmission amongst staff. Results: Of 42 personnel, 92.8% had a tertiary level of education while 71.4% had at least 5 years work experience. A total of 5 (11.9%) out of 42 HCWs were positive by week six of the study. All infected persons worked at the drive through centre. Most common symptom filled in the daily log tool was headache and fatigue. Conclusion: Despite all the measures introduced, 11.9% of HCWs became positive within 6 weeks, showing the highly infectious nature of the virus and the need to research into more effective measures in preventing the transmission of highly infectious pathogens to HCWs during outbreaks.

The present global pandemic triggered by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has lingered for over a year in its devastating effects. Diagnosis of coronavirus disease 2019 (COVID-19) is currently established with a polymerase chain reaction (PCR) test by means of oropharyngeal-, nasopharyngeal-, anal-swabs, sputum and blood plasma. However, oral and nasal swabs are more commonly used. This study, therefore, assessed sensitivity and specificity of plasma as a diagnostic in comparison with a combination of oral and nasal swab samples, and the implications for blood transfusion. Oropharyngeal (OP) and nasopharyngeal (NP) swab samples were obtained from 125 individuals suspected to have COVID-19 and stored in viral transport medium (VTM) tubes. Ten millilitres of blood samples in EDTA were also obtained by venepuncture and spun to obtain plasma. Viral RNA was obtained from both swabs and plasma by manual extraction with Qiagen QIAamp viral RNA Mini Kit. Detection was done using a real time fluorescent RT-qPCR BGI kit, on a QuantStudio 3 real-time PCR instrument. Average age of study participants was 41 years, with 74 (59.2%) being male. Out of the 125 individuals tested for COVID-19, 75 (60%) were positive by OP/NP swab. However, only 6 (4.8%) had a positive plasma result for COVID-19 with median Ct value of 32.4. Sensitivity and specificity of RT-PCR SARS-CoV-2 test using plasma was 8% and 100% respectively. There was no false positive recorded, but 69 (55.2%) false negatives were obtained by plasma. SARS-CoV-2 viral RNA was detected, albeit low (4.8%) in plasma. Plasma is likely not a suitable biological sample to diagnose acute SARS-CoV-2 infection. The implication of transfusing blood in this era of COVID-19 needs further investigations.

Correspondence - No abstract available.

In an outbreak, effective detection of the aetiological agent(s) involved using molecular techniques is key to efficient diagnosis, early prevention and management of the spread. However, sequencing is necessary for mutation monitoring and tracking of clusters of transmission, development of diagnostics and for vaccines and drug development. Many sequencing methods are fast evolving to reduce test turn-around-time and to increase through-put compared to Sanger sequencing method; however, Sanger sequencing remains the gold standard for clinical research sequencing with its 99.99% accuracy This study sought to generate sequence data of SARS-CoV-2 using Sanger sequencing method and to characterize them for possible site(s) of mutations. About 30 pairs of primers were designed, synthesized, and optimized using endpoint PCR to generate amplicons for the full length of the virus. Cycle sequencing using BigDye Terminator v.3.1 and capillary gel electrophoresis on ABI 3130xl genetic analyser were performed according to the manufacturers’ instructions. The sequence data generated were assembled and analysed for variations using DNASTAR Lasergene 17 SeqMan Ultra. Total length of 29,760bp of SARS-CoV-2 was assembled from the sample analysed and deposited in GenBank with accession number: MT576584. Blast result of the sequence assembly shows a 99.97% identity with the reference sequence. Variations were noticed at positions: nt201, nt2997, nt14368, nt16535, nt20334, and nt28841-28843, which caused amino acid alterations at the S (aa614) and N (aa203-204) regions. The mutations observed at S and N-gene in this study may be indicative of a gradual changes in the genetic coding of the virus hence, the need for active surveillance of the viral genome.

The first case of COVID-19 in Nigeria was recorded on February 27, 2020, being an imported case by an Italian expatriate, to the country. Since then, there has been steady increase in the number of cases. However, the number of cases in Nigeria is low in comparison to cases reported by other countries with similar large populations, despite the poor health system prevailing in the country. This has been mainly attributed to the low testing capacity in Nigeria among other factors. Therefore, there is a need for innovative ways to increase the number of persons testing for COVID-19. The aim of the study was to pilot a nasopharyngeal swab self-sample collection model that would help increase COVID-19 testing while ensuring minimal person-to-person contact being experienced at the testing center. 216 participants took part in this study which was carried out at the Nigerian Institute of Medical Research between June and July 2020. Amongst the 216 participants, 174 tested negatives for both self-collected samples and samples collected by Professionals, 30 tested positive for both arms, with discrepancies occurring in 6 samples where the self-collected samples were positive while the ones collected by the professionals were negative. The same occurred in another set of 6 samples with the self-collected samples being negative and the professional—collected sample coming out positive, with a sensitivity of 83.3% and a specificity of 96.7%. The results of the interrater analysis are Kappa = 0.800 (95% CI, 0.690 to 0.910) which implies an outstanding agreement between the two COVID-19 sampling methods. Furthermore, since p< 0.001 Kappa (k) coefficient is statistically different from zero, our findings have shown that self-collected samples can be reliable in the diagnosis of COVID-19.

INTRODUCTION: Heightened surveillance of the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) 2019 outbreak in Wuhan, China activated several collaborative laboratory drills on its detection by health institutions in Nigeria. We hereby detail the laboratory detection and confirmation of the novel SARS-CoV-2 virus of the index case imported into Nigeria. METHODS: viral RNA from sputum sample of the index case was tested for SARS-CoV-2 envelope (E) and RNA dependent RNA polymerase (RdRp) genes using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Genetic analysis using a partial sequence of RdRp gene was used for laboratory confirmation, evolutionary inferences, and relatedness to previous strains of betacoronaviruses in Nigeria. RESULTS: both qRT-PCR for the E and RdRp genes indicated the presence of the SARS-CoV-2 RNA by showing cycle threshold (ct) values of 20.27 and 25.26 respectively. On successful completion of the sequencing run, data aligned with >98% similarity of the 2019 circulating strain of Coronavirus SARS-CoV-2. Evolutionary algorithms revealed that the sequence (RdRp gene) of the outbreak circulating strains were more conserved unlike previous coronavirus outbreaks. Data showed that some coronaviruses belonging to the BetaCoV genus had earlier been reported in bats and camels in Nigeria indicating the possibility of sero-protection in exposed populations. CONCLUSIONS: pre-laboratory drills prompted early diagnosis and confirmation of SARS-CoV-2 index case in Nigeria initiating rapid case-definition, contact tracing, and successful epidemiological management of the outbreak. Rapid sequencing of the viral genome during strategic points of the outbreak curve and making libraries of new variants for improved vaccine development are recommended.

Background The increasing trends of morbidity and mortality of Lassa fever is becoming more alarming in Nigeria. Information about immune response to the virus is limited. At exposure, the level of immunity plays a vital role in the vulnerability of individuals infected. Objective Investigating the immune status of health workers, infected cases and contacts of infected cases of Lassa fever in Ondo State. Study Design Blood samples were collected from 233 individuals comprising 102 health workers, 22 infected cases and 109 contacts of infected cases from Owo and Ose Local Government Areas and transported in triple level packaging. Plasma samples were analyzed for IgG and IgM markers using ReLASV® Pan-Lassa NP IgG/IgM ELISA Kit (Zalgen Labs, LLC, USA) while RNAs extracted from IgM positive samples were analyzed for LASV RNA according to manufacturers’ instructions. Result Among the health workers, 20/102 (19.6%) and 2/102 (2.0%) were IgG and IgM positive respectively. While 16/22 (72.7%) and 14/22 (63.6%) were IgG and IgM positive respectively among the infected cases. Of the contacts of infected cases screened, 64/109 (58.7%) were IgG positive while 4/109 (3.7%) were positive for IgM. There was no detectable LASV RNA in the samples analyzed. Conclusion These findings suggest that majority of the health workers are naive to the virus and hence may be prone to the viral infection. It could also be suggestive that a good personal protective procedure is been practiced by the health workers, hence the low exposure. However, most of the contacts of infected cases show exposure to the virus.

A key element in containing the spread of the SARS-CoV-2 infection is quality diagnostics which is affected by several factors. We now report the comparative performance of five real-time diagnostic assays. Nasopharyngeal swab samples were obtained from persons seeking a diagnosis for SARS-CoV-2 infection in Lagos, Nigeria. The comparison was performed on the same negative, low, and high-positive sample set, with viral RNA extracted using the Qiagen Viral RNA Kit. All five assays are one-step reverse transcriptase real-time PCR assays. Testing was done according to each assay’s manufacturer instructions for use using real-time PCR platforms. 63 samples were tested using the five qPCR assays, comprising of 15 negative samples, 15 positive samples (Ct = 16–30; one Ct = 35), and 33 samples with Tib MolBiol E-gene Ct value ranging from 36–41. All assays detected all high positive samples correctly. Three assays correctly identified all negative samples while two assays each failed to correctly identify one different negative sample. The consistent detection of positive samples at different Ct/Cq values gives an indication of when to repeat testing and/or establish more stringent in-house cut-off value. The varied performance of different diagnostic assays, mostly with emergency use approvals, for a novel virus is expected. Comparative assays’ performance reported may guide laboratories to determine both their repeat testing Ct/Cq range and/or cut-off value.