COVID-19 Subclinical Infection and Immunity: A Review.

The aetiologic agent of COVID-19 is a novel coronavirus, SARS-CoV-2. Like other coronaviruses, it generally induces enteric and respiratory diseases in animals and humans. COVID-19 may be subclinical, and symptomatic, ranging from mild-to-severe disease. The spectrum of presentation is the result of several factors ranging from the inoculum size, inherent host susceptibility, possible cross-reacting circulating antibodies. Subclinical viral infections are associated with widespread community transmission and in some cases like Polio, herd immunity. An understanding of the biology and immune behavior in subclinical coronavirus disease 2019 (COVID-19) might be useful in the quest for vaccine development as well as the current control efforts against the COVID-19 pandemic. We carried out a narrative review of the available literature on the biology, etiopathogenesis, clinical manifestation of SARS-CoV-2 viral infection, focusing on our current understanding of the disease mechanisms and its clinical manifestation, and the host immune response to the infection. We also highlighted some of the research gaps regarding subclinical infection in COVID-19 and its potential application for vaccine development and other preventive efforts toward containing the current COVID-19 pandemic.

At-birth vaccination timeliness: An analysis of inborns in the highlands of Jos, North-Central Nigeria.

INTRODUCTION: Immunisation and vaccination programmes are preventive and cost-effective child health interventions for reducing childhood mortality and disability from infectious diseases. Timely administration of these vaccines is important to ensure their effectiveness in disease prevention. AIM: The aim was to determine the timeliness, barriers and predictors of at-birth vaccinations. MATERIALS AND METHODS: This was a cross-sectional study of 355 mother-newborn pairs using simple random sampling technique by balloting. SPSS version 23.0 was used for data analysis. Crude and adjusted odds ratios (AORs) were used as point estimates in the binary logistic regression model, while 95% confidence interval (CI) was used as the interval estimate. A P < 0.05 was considered statistically significant for the study. RESULTS: The mean age of the mothers was 31.0 ± 6 years. The median age of newborns at vaccination was 18 h (IQR = 1 - 17) h. About 185 (52.1%) of the newborns studied were males. Only 191 (53.8%) newborns received at-birth vaccination within 24 h of life. Weekend delivery, birth outside vaccination days, delivery during public holidays and vaccine stock-outs were barriers to timely vaccinations. Private hospital delivery was an independent predictor of delayed at-birth vaccinations (AOR = 2.616; 95% CI = 1.382-4.951). CONCLUSIONS: Our study has identified weekend delivery, preterm birth, delivery outside vaccination days and vaccines stock-outs as barriers to timely at-birth vaccinations. Private hospital delivery is a significant predictor of delayed at-birth vaccinations.

Pathogenesis, diagnostic challenges and treatment of zika virus disease in resource-limited settings.

The association of Zika virus (ZIKV) infection with congenital malformation and neurological sequelae has brought significant global concern. Consequently, the World Health Organization (WHO) declared it "a public health emergency of International concern" on 1 February, 2016. A critical review of its pathogenesis would lead to a better understanding of the clinical features and the neurological complications. This review is based on literature search in PubMed/Medline, Google Scholar and the WHO, http://www.who.int. This include all relevant articles written in English published through June 2018, with subject heading and keywords such as Zika, ZIKV, Zika pathogenesis, diagnosis of Zika, Zika Nigeria, Zika Africa and Zika resource-limited settings. Following ZIKV infection, viraemia ensues targeting primarily the monocytes for both the Asian and African strains. ZIKV infection by an African strain appears to be more pathogenic, in early pregnancy tends to result in spontaneous abortion. Whereas an Asian strain tends to be less pathogenic and more chronic, this allows the pregnancy to continue, ultimately resulting in congenital malformations. There is no routine laboratory diagnosis of ZIKV infection in resource-constrained countries. Serologic tests should be interpreted with caution since there can be cross-reactivity with other flaviviruses, especially in Africa where the burden of infection with flaviviruses is comparatively high. There is a paucity of well-equipped laboratories for comprehensive ZIKV diagnosis. It is imperative to strengthen the health systems, improve health workforce and diagnostic capacity of such settings.

Clinical profile and Predictors of Outcomes of Hospitalized Patients with Laboratory-Confirmed Severe Acute Respiratory Syndrome Coronavirus 2 in Nigeria: A Retrospective Analysis of 13 High Burden States in Nigeria.

Background: The majority of global COVID deaths have occurred in developed countries. Not much is known about the clinical outcomes for the patients admitted with COVID in Nigeria. We thus described the clinical characteristics, outcomes, and predictors of outcomes of hospitalized Nigerian COVID-19 patients. Methodology: We performed multilevel and mixed effects regression, Kaplan-Meir survival, and Cox proportionate hazards analyses to evaluate factors associated with death in patients admitted for COVID-19 in 13 high-burden states of Nigeria between 25th February 2020 and 30th August 2021. Results: Of the 3462 patients (median age, 40 years (interquartile range 28 years 54 years), 2,990(60.6%) were male and, 213(6.15%) of them died while on admission. Male sex (adjusted odds ratio [aOR], 1.78 [95% confidence interval {CI}, 1.23-2.56]), age group 45-65 years (OR, 3.93 [95% CI, 1.29-12.02]), age group 66-75 years (aOR, 5.37 [95% CI, 1.68-17.14]), age group > 75 years (aOR, 6.81 [95% CI, 2.04-22.82]), chronic cardiac disease (aOR, 3.07 [95% CI, 1.20-7.86]), being diabetic (aOR, 2.16 [95% CI, 1.41-3.31]), and having chronic kidney disease (OR, 11.01 [95% CI, 2.74-44.24]),were strongly associated with increased odds of death. Having concurrent malaria (aOR, 0.45 [95% CI, 0.16-1.28]), use of Azithromycin for treatment (aOR, 0.33 [95% CI, 0.19-0.54]), and use of Chloroquine/Hydroxychloroquine for treatment (aOR, 0.07 [95% CI, 0.03-0.14]) were significantly associated with decreased odds of death. Conclusions: The cumulative probability of death of male patients, diabetics, hypertensives, and patients with CKD was higher than that of female patients and those without those comorbidities while concurrent malaria and use of chloroquine/hydroxychloroquine in the treatment regimen were associated with a decreased risk of dying in patients treated in our isolation centers.

A 33-year-old patient with human immunodeficiency virus on antiretroviral therapy with efavirenz-induced complex partial seizures: a case report.

BACKGROUND: Efavirenz is a commonly prescribed antiretroviral drug that is largely well tolerated. However, seizure disorder is a rare side effect. Prompt identification and immediate replacement of efavirenz with an alternative drug would effectively stop the seizures. To the best of our knowledge, we present the first reported case in the literature of complex partial seizures arising due to efavirenz. CASE PRESENTATION: We report a case of a 33-year-old Nigerian man treated with an efavirenz-based antiretroviral regimen for human immunodeficiency virus infection. He presented with seizures soon after commencement of antiretroviral drugs. His magnetic resonance imaging results were unremarkable. His blood levels of sodium, glucose, urea, and creatinine were within normal limits. However, his electroencephalogram showed intermittent bursts of high-voltage sharp waves and spikes bilaterally over frontotemporoparietal regions, a finding consistent with complex partial seizures. His efavirenz plasma level was 209.55 µg/ml. His seizures stopped following a switch to a non-efavirenz-based regimen. CONCLUSIONS: This report brings to light the occurrence of complex partial seizures in patients on efavirenz. It also demonstrates the effective resolution of seizures when efavirenz treatment is replaced with a non-efavirenz-based regimen.