Humoral and cellular immune responses to Lassa fever virus in Lassa fever survivors and their exposed contacts in Southern Nigeria.

Elucidating the adaptive immune characteristics of natural protection to Lassa fever (LF) is vital in designing and selecting optimal vaccine candidates. With rejuvenated interest in LF and a call for accelerated research on the Lassa virus (LASV) vaccine, there is a need to define the correlates of natural protective immune responses to LF. Here, we describe cellular and antibody immune responses present in survivors of LF (N = 370) and their exposed contacts (N = 170) in a LASV endemic region in Nigeria. Interestingly, our data showed comparable T cell and binding antibody responses from both survivors and their contacts, while neutralizing antibody responses were primarily seen in the LF survivors and not their contacts. Neutralizing antibody responses were found to be cross-reactive against all five lineages of LASV with a strong bias to Lineage II, the prevalent strain in southern Nigeria. We demonstrated that both T cell and antibody responses were not detectable in peripheral blood after a decade in LF survivors. Notably LF survivors maintained high levels of detectable binding antibody response for six months while their contacts did not. Lastly, as potential vaccine targets, we identified the regions of the LASV Glycoprotein (GP) and Nucleoprotein (NP) that induced the broadest peptide-specific T cell responses. Taken together this data informs immunological readouts and potential benchmarks for clinical trials evaluating LASV vaccine candidates.

Co-infection and Risk Factors Associated with STIs among Pregnant Women in Rural Health Facilities in Nigeria: A Retrospective Study.

Globally, sexually transmitted infections are recognized as a public and reproductive health challenge. The study determined the prevalence, co-infection, and risk factors associated with HBV, HCV, HIV, and Syphilis infections among pregnant women receiving antenatal care in rural health facilities in Ebonyi State, Nigeria. A retrospective study was conducted from January to December 2018 in 8 primary healthcare facilities using antenatal records of all the 4657 pregnant women who attended ANC within the period. Data were analyzed using descriptive and inferential statistics with IBM SPSS statistics version 20 and hypotheses tested at P < .05. The findings indicated a medium prevalence of HBV (4.1%), a high prevalence of HCV (4.1%) and syphilis (1.8%), and a low prevalence of HIV (0.9%). An overall co-infection rate of 0.623% that was not significant (P > .05) was observed. Also, prevalence was more among the younger mothers (<20 years), those with secondary education. And the history of blood transfusion was significantly associated with HBV and HCV prevalence (χ2 = 7.865; P = .05*), 11.8%. conclusively, due to medium HBV prevalence and a high prevalence of HCV and syphilis observed, attention should be paid to blood screening before transfusion by health workers. Relevant stakeholders should provide intensive health education and appropriate free treatment services particularly for younger mothers and the less educated.

Investigating Factors Associated with Immunization Incompletion of Children Under Five in Ebonyi State, Southeast Nigeria: Implication for Policy Dialogue.

Purpose. To investigate factors associated with immunization incompletion of children under 5 years in Ebonyi state, Southeastern part of Nigeria. Method. A cross-sectional and a cluster sampling design were implemented; 400 women of childbearing age in families with children between 0 to 59 months of age were interviewed in Ebonyi state. Demographic characteristics of the child and mother, the child's immunization history, and reasons for partial immunization were obtained with the use of a self-administered questionnaire. Data were analyzed using descriptive statistics of mean, standard deviation, t-test and ANOVA with SPSS version 23 and hypothesis tested at P < .05. Results. Findings revealed that 180 (48.1%) females, and 194 (51.9%) males' children were immunized; Less than half 155 (41.9%) of the children had 1 missed dose, considered as partial immunization cases indicating low coverage. Of the reasons given for incomplete immunization mothers, mothers agreed that immunization centers are far from home (x̄ = 2.55 ± 0.92). This reason significantly affects mothers who were young (≤20 years) (x = 2.86 ± 0.94; P = .018), single (x = 2.84 ± 1.05; 0.037), had secondary education (x = 2.65 ± 1.08;0.000), students (2.89 ± 1.08; P = .000), poor (x = 2.63 ± 1.05; P = .009), and primiparous (x = 2.50 ± 1.08; P = .036) are more affected and they agreed (grand mean >2.50). Conclusion. Immunization coverage was low, and far location from health facility was indicted thus policy implementers should locate health facilities close to homes. also health education on the importance of immunization should be given to mothers especially those who are young and has low socio-economic status.

Prevalence and outcome of Lassa fever among hospitalized patients in Ebonyi State, Nigeria, 2018-2019.

Lassa fever (LF) is a viral hemorrhagic illness endemic in West Africa. Annually, about 300,000-500,000 people are being infected, with about 5000 deaths. Symptoms of LF include high grade fever, headache, malaise, abdominal pain, vomiting, diarrhea, or sore throat. Terminal features may include bleeding from all orifices (mouth, nose, ear, anus and vagina), facial and neck oedema or pleural effusion. People of all ages, gender, and occupations were included in this study. A total of 440 patients' samples and Bio data were used for this study. The samples were analyzed for Lassa fever virus RNA using Real Time Reverse Transcriptase Polymerase Chain Reaction. The data obtained were analyzed using SPSS 20.0 and version 7 of Epi-Info statistical software. Analysis of these samples showed LASV prevalence of 25.7%. Chi-square analysis (p ≤ 0.05) showed that LASV infection does not depend on age, gender, or occupation. Our research re-emphasized the fact that LASV is a serious cause of fatality in humans. Our data showed that among 327 negative patients, 19 died. On the contrary, 113 LASV confirmed positive cases had 42 deaths. This result is highly significant. More so, Lassa fever disease outcome was compared across gender. There was no significant difference between the two genders. Death or recovery from LF infection does not depend on sex. However, recovery from LF significantly depends on age of the patient. Fatal outcome is significantly higher among adults/elderly. We aim to raise awareness to the recurrence of LASV in Ebonyi State and urgent need for other medical interventions, including other therapeutic measures, and possible vaccine production, considering the impact of this virus.

Development of an RT-LAMP assay for the detection of Lassa viruses in southeast and south-central Nigeria.

Lassa virus (LASV) causes Lassa fever (LF), a viral hemorrhagic fever endemic in West Africa. LASV strains are clustered into six lineages according to their geographic location. To confirm a diagnosis of LF, a laboratory test is required. Here, a reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay using a portable device for the detection of LASV in southeast and south-central Nigeria using three primer sets specific for strains clustered in lineage II was developed. The assay detected in vitro transcribed LASV RNAs within 23 min and was further evaluated for detection in 73 plasma collected from suspected LF patients admitted into two health settings in southern Nigeria. The clinical evaluation using the conventional RT-PCR as the reference test revealed a sensitivity of 50% in general with 100% for samples with a viral titer of 9500 genome equivalent copies (geq)/mL and higher. The detection limit was estimated to be 4214 geq/mL. The assay showed 98% specificity with no cross-reactivity to other viruses which cause similar symptoms. These results suggest that this RT-LAMP assay is a useful molecular diagnostic test for LF during the acute phase, contributing to early patient management, while using a convenient device for field deployment and in resource-poor settings.