DETERMINANTS OF PRETERM BIRTH AMONG MOTHERS WHO GAVE BIRTH AT A REFERRAL HOSPITAL, NORTHWEST ETHIOPIA: UNMATCHED CASE- CONTROL STUDY

Preterm birth is described as babies that are born alive before the end of 37 weeks of pregnancy. About 15 million babies are born preterm annually and more than a million died due to complications. In developing nations, like Ethiopia, PTB is underreported and underestimated. Objective - to identify determinates of preterm birth among mothers who gave birth at Felege Hiwot Comprehensive Specialized Referral Hospital, Northwest Ethiopia. Unmatched case-control study design was conducted. The total sample size was 558 mothers 140 cases and 418 controls. Simple random sampling was used to select the study population. Data were coded and entered into Epidata, version 3.2, and was analyzed by using STATA version 14. Mothers with a history of antepartum hemorrhage (AOR 3.53, 95% CI 1.31-9.47), premature rupture of membrane (AOR 8.9, 95% CI 4.51-17.57), pregnancy-induced hypertension (AOR 3.65, 95% CI 1.78-7.51), history of multiple pregnancies (AOR 2.49, 95% CI 0.89-6.95), primigravida (AOR 0.16, 95% CI 0.03-0.97) and Primiparity(AOR 0.054, 95% CI 0.05-0.64) had statistically significant association with experiencing preterm birth. The odds of giving preterm birth were higher among women with antepartum hemorrhage, PIH, PROM, and multiple pregnancies, but lower among primigravida and primiparous mothers.

Efficacy of multivalent recombinant herpesvirus of turkey vaccines against high pathogenicity avian influenza, infectious bursal disease, and Newcastle disease viruses

Vaccines are an essential tool for the control of viral infections in domestic animals. We generated recombinant vector herpesvirus of turkeys (vHVT) vaccines expressing computationally optimized broadly reactive antigen (COBRA) H5 of avian influenza virus (AIV) alone (vHVT-AI) or in combination with virus protein 2 (VP2) of infectious bursal disease virus (IBDV) (vHVT-IBD-AI) or fusion (F) protein of Newcastle disease virus (NDV) (vHVT-ND-AI). In vaccinated chickens, all three vHVT vaccines provided 90-100% clinical protection against three divergent clades of high pathogenicity avian influenza viruses (HPAIVs), and significantly decreased number of birds and oral viral shedding titers at 2 days post-challenge compared to shams. Four weeks after vaccination, most vaccinated birds had H5 hemagglutination inhibition antibody titers, which significantly increased post-challenge. The vHVT-IBD-AI and vHVT-ND-AI vaccines provided 100% clinical protection against IBDVs and NDV, respectively. Our findings demonstrate that multivalent HVT vector vaccines were efficacious for simultaneous control of HPAIV and other viral infections.

Experiences of introducing new drugs for drug-resistant TB at the ALERT Hospital, Addis Ababa, Ethiopia, 2017-2019

BACKGROUND

Drug-resistant TB (DR-TB) remains a major public health concern. DR-TB patient data from ALERT (All Africa Leprosy, Tuberculosis and Rehabilitation Training Centre) Hospital, Addis Ababa, Ethiopia, who received bedaquiline (BDQ) and/or delamanid (DLM) containing regimens were analysed.

RESULTS

From 2017 to 2019, 51 DR-TB patients were enrolled. Of 33 patients, 31 (93.9%) had culture converted at 6 months. Of those with final outcomes, 77% (n = 10) were cured. Thirty (58.8%) developed adverse events, the most frequent of which were gastrointestinal disorders (70%), haematological disorders (16.7%) and QTc prolongation (16.7%). Twenty patients discontinued the offending drug permanently.

CONCLUSION

With close monitoring, introduction of new DR-TB regimens brought good early results, which encouraged wider programmatic implementation in Ethiopia.

Efficacy of recombinant Marek's disease virus vectored vaccines with computationally optimized broadly reactive antigen (COBRA) hemagglutinin insert against genetically diverse H5 high pathogenicity avian influenza viruses

The genetic and antigenic drift associated with the high pathogenicity avian influenza (HPAI) viruses of Goose/Guangdong (Gs/GD) lineage and the emergence of vaccine-resistant field viruses underscores the need for a broadly protective H5 influenza A vaccine. Here, we tested experimental vector herpesvirus of turkey (vHVT)-H5 vaccines containing either wild-type clade 2.3.4.4A-derived H5 inserts or computationally optimized broadly reactive antigen (COBRA) inserts with challenge by homologous and genetically divergent H5 HPAI Gs/GD lineage viruses in chickens. Direct assessment of protection was confirmed for all the tested constructs, which provided clinical protection against the homologous and heterologous H5 HPAI Gs/GD challenge viruses and significantly decreased oropharyngeal shedding titers compared to the sham vaccine. The cross reactivity was assessed by hemagglutinin inhibition (HI) and focus reduction assay against a panel of phylogenetically and antigenically diverse H5 strains. The COBRA-derived H5 inserts elicited antibody responses against antigenically diverse strains, while the wild-type-derived H5 vaccines elicited protection mostly against close antigenically related clades 2.3.4.4A and 2.3.4.4D viruses. In conclusion, the HVT vector, a widely used replicating vaccine platform in poultry, with H5 insert provides clinical protection and significant reduction of viral shedding against homologous and heterologous challenge. In addition, the COBRA-derived inserts have the potential to be used against antigenically distinct co-circulating viruses and future drift variants.

Evaluating the integration of tuberculosis screening and contact investigation in tuberculosis clinics in Ethiopia: A mixed method study

Background

Aligned with global childhood tuberculosis (TB) road map, Ethiopia developed its own in 2015. The key strategies outlined in the Ethiopian roadmap are incorporating TB screening in Integrated Maternal, Neonatal and Child Illnesses (IMNCI) clinic for children under five years (U5) and intensifying contact investigations at TB clinic. However, these strategies have never been evaluated.

Objective

To evaluate the integration of tuberculosis (TB) screening and contact investigation into Integrated Maternal, Neonatal and Child Illnesses (IMNCI) and TB clinics in Addis Ababa, Ethiopia.

Methods

The study used mixed methods with stepped-wedge design where 30 randomly selected health care facilities were randomized into three groups of 10 during August 2016-November 2017. The integration of TB screening into IMNCI clinic and contact investigation in TB clinic were introduced by a three-day childhood TB training for health providers. An in-depth interview was used to explore the challenges of the interventions and supplemented data on TB screening and contact investigation.

Results

Overall, 180896 children attended 30 IMNCI clinics and145444 (80.4%) were screened for TB. A total of 688 (0.4%) children had presumptive TB and 47(0.03%) had TB. During the pre-intervention period, 51873 of the 85278 children (60.8%) were screened for TB as compared to 93570 of the 95618 children (97.9%) in the intervention (p<0.001). This had resulted in 149 (0.30%) and 539 (0.6%) presumptive TB cases in pre-intervention and intervention periods (p<0.001), respectively. Also, nine TB cases (6.0%) in pre-intervention and 38 (7.1%) after intervention were identified (p = 0.72). In TB clinics, 559 under-five (U5) contacts were identified and 419 (80.1%) were screened. In all, 51(9.1%) presumed TB cases and 12 (2.1%) active TB cases were identified from the traced contacts. TB screening was done for 182 of the 275 traced contacts (66.2%) before intervention and for 237 of the 284 of the traced (83.5%) under intervention (p<0.001). Isoniazid prevention therapy (IPT) was initiated for 69 of 163 eligible contacts (42.3%) before intervention and for 159 of 194 eligible children (82.0%) under intervention (p<0.001). Over 95% of health providers indicated that the integration of TB screening into IMNCI and contact investigation in TB clinic is acceptable and practical. Gastric aspiration to collect sputum using nasogastric tube was reported to be difficult.

Conclusions

Integrating TB screening into IMNCI clinics and intensifying contact investigation in TB clinics is feasible improving TB screening, presumed TB cases, TB cases, contact screening and IPT coverage during the intervention period. Stool specimen could be non-invasive to address the challenge of sputum collection.

Contribution of intrinsic reactivity of the HIV-1 envelope glycoproteins to CD4-independent infection and global inhibitor sensitivity

Human immunodeficiency virus (HIV-1) enters cells following sequential activation of the high-potential-energy viral envelope glycoprotein trimer by target cell CD4 and coreceptor. HIV-1 variants differ in their requirements for CD4; viruses that can infect coreceptor-expressing cells that lack CD4 have been generated in the laboratory. These CD4-independent HIV-1 variants are sensitive to neutralization by multiple antibodies that recognize different envelope glycoprotein epitopes. The mechanisms underlying CD4 independence, global sensitivity to neutralization and the association between them are still unclear. By studying HIV-1 variants that differ in requirements for CD4, we investigated the contribution of CD4 binding to virus entry. CD4 engagement exposes the coreceptor-binding site and increases the "intrinsic reactivity" of the envelope glycoproteins; intrinsic reactivity describes the propensity of the envelope glycoproteins to negotiate transitions to lower-energy states upon stimulation. Coreceptor-binding site exposure and increased intrinsic reactivity promote formation/exposure of the HR1 coiled coil on the gp41 transmembrane glycoprotein and allow virus entry upon coreceptor binding. Intrinsic reactivity also dictates the global sensitivity of HIV-1 to perturbations such as exposure to cold and the binding of antibodies and small molecules. Accordingly, CD4 independence of HIV-1 was accompanied by increased susceptibility to inactivation by these factors. We investigated the role of intrinsic reactivity in determining the sensitivity of primary HIV-1 isolates to inhibition. Relative to the more common neutralization-resistant ("Tier 2-like") viruses, globally sensitive ("Tier 1") viruses exhibited increased intrinsic reactivity, i.e., were inactivated more efficiently by cold exposure or by a given level of antibody binding to the envelope glycoprotein trimer. Virus sensitivity to neutralization was dictated both by the efficiency of inhibitor/antibody binding to the envelope glycoprotein trimer and by envelope glycoprotein reactivity to the inhibitor/antibody binding event. Quantitative differences in intrinsic reactivity contribute to HIV-1 strain variability in global susceptibility to neutralization and explain the long-observed relationship between increased inhibitor sensitivity and decreased entry requirements for target cell CD4.

Synthesis of a trimeric gp120 epitope mimic conjugated to a T-helper peptide to improve antigenicity

A fully synthetic trivalent mimotope of gp120 conjugated to pan allelic HLA DR binding epitope was prepared using solid-phase peptide synthesis and optimized copper-catalyzed azide-alkyne cycloaddition. The methodology efficiently provides chemically uniform heteromultimeric peptide constructs with enhanced binding, avidity, and specificity toward an established HIV-neutralizing human antibody, MAb b12. The versatile synthetic strategy serves as a powerful platform for the development of synthetic peptides as potential HIV-1 vaccine candidates.

Topological layers in the HIV-1 gp120 inner domain regulate gp41 interaction and CD4-triggered conformational transitions

The entry of human immunodeficiency virus (HIV-1) into cells is initiated by binding of the gp120 exterior envelope glycoprotein to the receptor, CD4. How does CD4 binding trigger conformational changes in gp120 that allow the gp41 transmembrane envelope glycoprotein to mediate viral-cell membrane fusion? The transition from the unliganded to the CD4-bound state is regulated by two potentially flexible topological layers (layers 1 and 2) in the gp120 inner domain. Both layers apparently contribute to the noncovalent association of unliganded gp120 with gp41. After CD4 makes initial contact with the gp120 outer domain, layer 1-layer 2 interactions strengthen gp120-CD4 binding by reducing the off rate. Layer 1-layer 2 interactions also destabilize the activated state induced on HIV-1 by treatment with soluble CD4. Thus, despite lack of contact with CD4, the gp120 inner-domain layers govern CD4 triggering by participating in conformational transitions within gp120 and regulating the interaction with gp41.

Soluble CD4 and CD4-mimetic compounds inhibit HIV-1 infection by induction of a short-lived activated state

Binding to the CD4 receptor induces conformational changes in the human immunodeficiency virus (HIV-1) gp120 exterior envelope glycoprotein. These changes allow gp120 to bind the coreceptor, either CCR5 or CXCR4, and prime the gp41 transmembrane envelope glycoprotein to mediate virus–cell membrane fusion and virus entry. Soluble forms of CD4 (sCD4) and small-molecule CD4 mimics (here exemplified by JRC-II-191) also induce these conformational changes in the HIV-1 envelope glycoproteins, but typically inhibit HIV-1 entry into CD4-expressing cells. To investigate the mechanism of inhibition, we monitored at high temporal resolution inhibitor-induced changes in the conformation and functional competence of the HIV-1 envelope glycoproteins that immediately follow engagement of the soluble CD4 mimics. Both sCD4 and JRC-II-191 efficiently activated the envelope glycoproteins to mediate infection of cells lacking CD4, in a manner dependent on coreceptor affinity and density. This activated state, however, was transient and was followed by spontaneous and apparently irreversible changes of conformation and by loss of functional competence. The longevity of the activated intermediate depended on temperature and the particular HIV-1 strain, but was indistinguishable for sCD4 and JRC-II-191; by contrast, the activated intermediate induced by cell-surface CD4 was relatively long-lived. The inactivating effects of these activation-based inhibitors predominantly affected cell-free virus, whereas virus that was prebound to the target cell surface was mainly activated, infecting the cells even at high concentrations of the CD4 analogue. These results demonstrate the ability of soluble CD4 mimics to inactivate HIV-1 by prematurely triggering active but transient intermediate states of the envelope glycoproteins. This novel strategy for inhibition may be generally applicable to high–potential-energy viral entry machines that are normally activated by receptor binding.

Human immunodeficiency virus type 1 (HIV-1) is the cause of the global AIDS epidemic. HIV-1 gains entry into its target cells by fusing with the cell membrane, a process that begins with the interaction of the viral envelope glycoproteins with cell-surface receptors. HIV-1 uses two receptors on the target cell: CD4 and CCR5/CXCR4. Binding of the virus to the primary receptor, CD4, primes the viral envelope glycoproteins to mediate the fusion of the viral membrane and the membrane of the target cell. Soluble forms of the CD4 receptor and small molecules that mimic the effects of CD4 can inhibit virus infection; however, how this inhibition occurs is still unknown. In this report, we show that soluble mimics of CD4 inhibit HIV-1 infection by prematurely triggering the viral envelope glycoproteins. The unstable activated state of the virus lasts only a few minutes, after which the virus loses the ability to infect cells. This novel strategy for inhibition may be generally applicable to other viruses besides HIV-1, some of which are also activated by binding to their receptors.

Role of the gp120 inner domain beta-sandwich in the interaction between the human immunodeficiency virus envelope glycoprotein subunits

The inner domain of the human immunodeficiency virus (HIV-1) gp120 glycoprotein has been proposed to mediate the noncovalent interaction with the gp41 transmembrane envelope glycoprotein. We used mutagenesis to investigate the functional importance of a conserved beta-sandwich located within the gp120 inner domain. Changes in aliphatic residues lining a hydrophobic groove on the surface of the beta-sandwich decreased the association of the gp120 and gp41 glycoproteins. Other changes in the base of the hydrophobic groove resulted in envelope glycoproteins that were structurally intact and able to bind receptors, but were inefficient in mediating either syncytium formation or virus entry. These results support a model in which the beta-sandwich in the gp120 inner domain contributes to gp120-gp41 contacts, thereby maintaining the integrity of the envelope glycoprotein complex and allowing adjustments in the gp120-gp41 interaction required for membrane fusion.

Study of the distribution of retinal blood vessels in buffaloes (Bos bubalis)

The distribution of retinal blood vessels in the eye of buffalo was studied macroscopically and microscopically in twenty-two eyes of healthy animals. After macroscopic observation, 12 of 22 eyes were used for histological study. Ten eyes were stained with hematoxylin and eosin and two eyes with PAS stain. The present findings revealed that the eye of the buffalo was characterized by the complex network of retinal blood vessels (holangiotic or euangiotic). The central retinal artery and vein pierced the eye through the optic disc and gave off several branches. There were four pairs of primary vessels that were named dorsal, ventral, nasal and temporal retinal arteries and veins. The veins anastmosed with each other at the optic disc to form a somewhat circle. Three patterns of the distribution of blood vessels were described. The distribution of the arteries and veins was the same.

Passive sentinel surveillance system for sexually transmitted diseases in primary healthcare sites in Ethiopia, 1991-3

BACKGROUND

In 1989 the ministry of health of Ethiopia launched an STD control programme to strengthen the STD case management capabilities at public health centres and hospitals. The programme included the introduction of a syndrome based system for notification of STD cases. We here report the data originated by the syndromic case reporting system under programme conditions.

METHODS

35 (17%) of the total 225 hospitals and public health centres of Ethiopia were included in the programme. Information relevant to the years 1991 to 1993 was analysed at mid 1994.

RESULTS

32 clinical sites (91% of the total) provided at least one monthly report. The proportion of monthly reports received was 65% of those due, ranging from 51% in 1991 to 73% in 1992 and 42% in 1993. A total of 77,294 consultations for STD related symptoms were recorded, including 70,200 new cases, 6588 repeated consultations, and 506 partners of STD patients. Among first attendant patients 38,459 (52.7%) were males with a male to female ratio of 1:1. Urethral discharge and vaginal discharge were the leading cause of consultation among males (58%) and females (64%) respectively. The frequency of genital ulcer diseases was 26% among males and 15% among females. Inguinal adenopathy in the absence of genital ulcers was also frequent, accounting for 10% of consulting males and 5% of females. Based on Gram stain, gonorrhoea was identified in 64% of the cases of urethral discharge, while trichomoniasis and candidiasis were identified by wet mount in 28% and 16% of the cases of vaginal discharge respectively.

CONCLUSIONS

STDs are a common cause of consultation at public health centre sites in Ethiopia. A syndromic case reporting system proved to be efficient and produced valuable information to initiate assessment of the problem and to set up bases for monitoring trends of STD morbidity.

[Pneumococcal cellulitis]

Streptococcus pneumoniae as a cause of cellulitis is rarely reported in children and adults. We report on an infant with facial cellulitis due to pneumococci and review already described cases since 1975. The main features of this infection, underlying diseases and problems of diagnostics and therapy are discussed.