Endemic Countries Research Articles

Hydatid Cyst in Leg Calves Simulating a Deep-Vein Thrombosis

Introduction: The localization of hydatid cysts in muscles is rare, even in endemic countries [1, 2]. This disease remains a major cause of morbidity worldwide. We report a case of a rare hydatid cyst in the calves, simulating deep vein thrombosis [DVT], while discussing its clinical and radiological features and its therapeutic management. The diagnosis was initially based on imaging and immunological reactions, and was confirmed by histology. Case Presentation: we report the case of a 36-year-old woman of rural origin, with a history of contact with dogs, referred to the emergency department with suspected thrombophlebitis of the lower limb, 3 days old. Palpation revealed a small, poorly defined mass on the posteromedial aspect of the leg, ultrasound revealed a deep collection in the upper 1/3 of the left leg, with multiple inflammatory lymph nodes in the left inguinal region. MRI revealed a heterogeneous liquid lesion formation. The patient underwent surgery, finding a formation measuring 13×11×3cm, which was completely resected. Conclusion: Soft tissue hydatid cysts are a rare localization of Echinococcus granulosus, and the detection of hydatid cysts when DVT is suspected underlines the continuing public health challenge posed by Echinococcus.

From Entry to Evasion: A Comprehensive Analysis of Host-Virus Interactions for Monkeypox

Abstract Monkeypox (Mpox) has posed a novel challenge and emerged as a threat to global public health since the onset of its outbreak in 2022. Mpox is spreading throughout the world in both endemic and non-endemic countries, indicating that its behavior is evolving. The prevalence of Mpox and the risk of a global pandemic necessitate a better understanding of Mpox virus replications and interactions with the host. Here, we attempted to provide a detailed comprehensive review of Mpox virus behavior at the molecular level from the entry level to the establishment of a successful infection, including attachment and entry, DNA replication, protein expression and viron assembly and egress. This review also describes its strategies to evade host immune responses and inhibit apoptosis, and uncovers underlying molecular mechanisms such as subverted signaling pathways and cellular factors behind host-viral interactions.

Sensitivity and specificity of newly generated monoclonal antibodies to detect novel antigens of Mycobacterium tuberculosis for the diagnosis of all forms of tuberculosis

Objectives: Tuberculosis (TB) is curable if diagnosed correctly and promptly. However, the lack of effective and accessible point-of-care tests hindered the systematic screening of TB. The current TB diagnostic methods, including molecular tests, have failed to deliver the capacity needed in the endemic countries to restrict the ongoing pandemic. The detection of Mycobacterium tuberculosis by serology offers several advantages, including rapid and low-cost disease detection. Earlier, we had evaluated the diagnostic utility of five novel recombinant antigens, namely, SS-1, SS-2, SS-3, SS-4, and SS-5, with Indian patient sera. However, antibody detection has some limitations, and therefore, in the present study, we aimed to generate monoclonal antibodies and explore the utility of the most promising antibodies for the detection of TB. Materials and Methods: We used the three best recombinant antigens, that is, Rv2145c (SS-1), Rv1827 (SS-4), and Rv2970c (SS-5) for the generation of monoclonal antibodies. The monoclonal antibodies were developed using hybridoma technology. Further, the diagnostic utility of these monoclonal antibodies was evaluated in diagnosis of TB by sandwich enzyme-linked immunosorbent assay. Serum samples from bacteriologically confirmed TB cases and controls were used. Statistical Analysis: All statistical analysis was carried out using STATA-11.1 software (StataCorp LP, Texas, USA). The sensitivity and specificity were computed using an online tool (OpenEpi). Statistically significant differences between groups were defined as p<0.05. Results: A total of 384 serum samples were included in the study. This included 144 pulmonary TB cases, 68 extrapulmonary TB cases, 50 disease controls and 125 healthy controls. The sensitivity and specificity of our three monoclonal antibodies (mAb_SS-1, mAb_SS-4, and mAb_SS-5) for detecting all forms of TB ranged from 86.49% to 97.44% and 96.57% to 98.29%, respectively. The receiver operative characteristic curve showed a significant statistical difference between TB and healthy subjects (P < 0.001). Conclusions: Our data suggested that mAb_SS-1, mAb_SS-4, and mAb_SS-5 could be used as potential TB screening tests, especially in the resource-limiting setting.

Aedes albopictus is a competent vector of five arboviruses affecting human health, greater Paris, France, 2023.

Aedes albopictus collected in 2023 in the greater Paris area (Île-de-France) were experimentally able to transmit five arboviruses: West Nile virus from 3 days post-infection (dpi), chikungunya virus and Usutu virus from 7 dpi, dengue virus and Zika virus from 21 dpi. Given the growing number of imported dengue cases reported in early 2024 in France, surveillance of Ae. albopictus should be reinforced during the Paris Olympic Games in July, when many international visitors including from endemic countries are expected.

Vector competence of Swedish Culex pipiens mosquitoes for Japanese encephalitis virus

BackgroundJapanese encephalitis virus (JEV) is an emerging mosquito-borne Orthoflavivirus that poses a significant public health risk in many temperate and tropical regions in Asia. Since the climate in some endemic countries is similar to temperate climates observed in Europe, understanding the role of specific mosquito species in the transmission of JEV is essential for predicting and effectively controlling the potential for the introduction and establishment of JEV in Europe.MethodsThis study aimed to investigate the vector competence of colonized Culex pipiens biotype molestus mosquitoes for JEV. The mosquitoes were initially collected from the field in southern Sweden. The mosquitoes were offered a blood meal containing the Nakayama strain of JEV (genotype III), and infection rates, dissemination rates, and transmission rates were evaluated at 14, 21, and 28 days post-feeding.ResultsThe study revealed that colonized Swedish Cx. pipiens are susceptible to JEV infection, with a stable infection rate of around 10% at all timepoints. However, the virus was only detected in the legs of one mosquito at 21 days post-feeding, and no mosquito saliva contained JEV.Conclusions Overall, this research shows that Swedish Cx. pipiens can become infected with JEV, and emphasizes the importance of further understanding of the thresholds and barriers for JEV dissemination in mosquitoes.Graphical

Sudan's rheumatic fever and rheumatic heart disease guidelines: a simplified approach in an endemic country.

Rheumatic heart disease (RHD) is a preventable sequelae of group A beta hemolytic streptococcal infection leading to an immune reaction: acute rheumatic fever (ARF) and progressive heart valve dysfunction. RHD is the leading cause of acquired heart disease in children and young adults in Sudan and many low/middle-income countries. In 2018, the World Health Organization (WHO) issued a resolution for RHD mandating that each country adopt updated guidelines for ARF and RHD management. These current guidelines are mainly directed to primary healthcare workers. Sudan's Federal Ministry of Health (FMOH) in collaboration with the WHO East Mediterranean Regional Office (EMRO) assembled a committee for updating RHD guidelines. We conducted a systematic literature search from 2000 to 2022 in National Institute of Health Database (PubMed) under the following titles: streptococcal pharyngitis, acute rheumatic fever, rheumatic heart disease, benzathine penicillin. Best available, evidence-based practices for diagnosis and management of ARF/RHD were selected and adapted to Sudan's situation. The guidelines were critically appraised by the committee then endorsed to the FMOH and WHO EMRO Noncommunicable Disease Departments in January 2023. This paper describes the updated guidelines. Simplified algorithms are provided for diagnosis of bacterial pharyngitis including two clinical criteria: sore throat and the absence of viral symptoms in the target age group. A simplified algorithm for diagnosis and management of ARF is adopted using two levels of diagnosis: suspected case at primary level where penicillin prophylaxis is started and secondary/tertiary care where echocardiography is performed and diagnosis confirmed or excluded. Echocardiography screening is recognized as the standard method for early diagnosis of RHD; however, due to the anticipated limitations, its implementation was not adopted at this time. Streptococcal skin infection is included as a precursor of ARF and a detailed protocol for benzathine penicillin administration is described. The Sudan guidelines for ARF/RHD management were updated. Endorsement of these guidelines to FMOH and WHO EMRO is expected to improve control of RHD in the region.

Efficacy of praziquantel drug against Schistosoma haematobium and performance of urine reagent strips among pre-and-school aged children during the high transmission season in North-Western Tanzania

The World Health Organization calls for schistosomiasis endemic countries to regularly monitor the efficacy of Praziquantel (PZQ) drug, the only antischistosomal drug used for four decades in Tanzania. In response to that call, the current study investigated the efficacy of single dose of PZQ against Schistosoma haematobium during the high transmission season and further assessed, the sensitivity and specificity of urine reagent strips before and after treatment. The study recruited a total of 2,498 -children aged (4 -17 years old) who provided a single urine sample that was visually examined for macro-haematuria, then using urine dipstick and urine filtration technique for microhaematuria and the presence of S. haematobium eggs. The baseline prevalence of S. haematobium eggs positive based on urine filtration test was 29.2 % (95 %CI:27.5–31.0) and that of microhaematuria was 43.1 % (95 %CI:41.1–45.0). Of the infected participants, 40.9 % (95 %CI:37.4–44.6) had a heavy intensity of infection and the geometrical mean intensity (GMI) of infection was 33.7 eggs/10mls of urine. A single dose of PZQ reduced the prevalence of infection to 16.2 %, the GMI of infection to 18.8eggs/10mls of urine and that of microhaematuria to 27.9 %. Cure rate and egg reduction rates (ERR) were 83.8 % and 44.3 % respectively. At baseline, the sensitivity and specificity of the urine reagent strips were 59.7 % and 93.8 %, whereas at post-treatment they were 16.7 % and 93.6 %. When PZQ drug is administered during the high transmission season, its efficacy in term of ERR is poor. The urine reagent strips had low sensitivity but high specificity at pre-and-post PZQ treatment.

Comparative evaluation of the diagnostic accuracies of four different malaria rapid diagnostic test kits available in Ghana.

Malaria rapid diagnostic test (mRDT) kit is one of the techniques for diagnosing malaria. Due to its inherent advantages over the microscopy technique, several brands of the kit have flooded malaria endemic countries, without prior in-country evaluation. Two of such mRDT kits are Oscar (India) and Standard Q (Korea Republic). In this study, the performance of Oscar and Standard Q mRDT kits were compared to First Response (India) and CareStart (USA) mRDTs, which have been evaluated and deployed for use approved by the Ministry of Health (MOH). In this comparative study, whole blood samples were collected from patients suspected of malaria. Plasmodium falciparum was detected in each sample using nested polymerase chain reaction (nPCR), microscopy and the four mRDTs. The sensitivities, specificities, accuracies, positive and negative predictive values and accuracies of the mRDTs were determined using nPCR as a reference technique. Kappa statistic was used to determine the level of agreement among the techniques. Two hundred (200) blood samples were analyzed in this study. The overall detection rates of P. falciparum by microscopy, First Response, CareStart, Oscar-PfHRP2, Standard Q mRDT kits and nPCR were 31.5%, 34.5%, 33.5%, 32%, 31% and 43% (x2 = 6.1, p = 0.046), respectively. The accuracies of CareStart and First Response were comparable (90.5% vs. 89.5%). Further, comparing their sensitivities, Oscar-PfHRP2 was 74.4% (95% confidence interval (CI): 63.9-83.2) while that of Standard Q was 72.1% (95% CI: 61.4-81.2), with comparable accuracies (Oscar-PfHRP2-89% and Standard Q -88%). Apart from First Response that was 98.3% specific, the others were 100% specific. Kappa test revealed perfect diagnostic agreement (κ = 0.90-0.98) among the four mRDTs. That notwithstanding, Oscar-PfHRP2 agreed better with CareStart (κ = 0.94) and First Response (κ = 0.92) compared to the agreement between Standard Q and, CareStart (κ = 0.92) and First Response (κ = 0.90). Taken together, the diagnostic performance of the four mRDT kits were statistically similar. That notwithstanding, new mRDT kits should be evaluated prior to deployment for use.

A simple, field-applicable method to increase the infectivity of wild isolates of Plasmodium falciparum to mosquito vectors

BackgroundThe direct membrane feeding assay (DMFA), whereby gametocyte-infected blood is collected from human donors and from which mosquitoes feed through a membrane, is proving essential for assessing parameters influencing Plasmodium transmission potential in endemic countries. The success of DMFAs is closely tied to gametocyte density in the blood, with relatively high gametocytaemia ensuring optimal infection levels in mosquitoes. As transmission intensity declines with control efforts, the occurrence of asymptomatic individuals with low gametocyte densities, who can significantly contribute to the infectious reservoir, is increasing. This poses a limitation to studies relying on the experimental infection of large numbers of mosquitoes with natural isolates of Plasmodium. A simple, field-applicable method is presented for improving parasite infectivity by concentrating Plasmodium falciparum gametocytes.MethodsAnopheles gambiae received one of the following 5 blood treatments through DMFA: (i) whole blood (WB) samples from naturally-infected donors; (ii) donor blood whose plasma was replaced with the same volume of Plasmodium-naive AB + serum (1:1 control); (iii) plasma replaced with a volume of malaria-naïve AB + serum equivalent to half (1:1/2), or to a quarter (1:1/4), of the initial plasma volume; and (v) donor blood whose plasma was fully removed (RBC). The experiment was repeated 4 times using 4 distinct wild parasite isolates. Seven days post-infection, a total of 1,095 midguts were examined for oocyst presence.ResultsSubstituting plasma with reduced amounts (1:1/2 and 1:1/4) of Plasmodium-naive AB + serum led to a 31% and 17% increase of the mosquito infection rate and to a 85% and 308% increase in infection intensity compared to the 1:1 control, respectively. The full removal of plasma (RBC) reduced the infection rate by 58% and the intensity by 64% compared to the 1:1 control. Reducing serum volumes (1:1/2; 1:1/4 and RBC) had no impact on mosquito feeding rate and survival when compared to the 1:1 control.ConclusionsConcentrating gametocytic blood by replacing natural plasma by lower amount of naive serum can enhance the success of mosquito infection. In an area with low gametocyte density, this simple and practical method of parasite concentration can facilitate studies on human-to-mosquito transmission such as the evaluation of transmission-blocking interventions.

Epidemiological Risk Factors and Modelling Approaches for Risk Assessment of Lumpy Skin Disease Virus Introduction and Spread: Methodological Review and Implications for Risk-Based Surveillance in Australia

Lumpy skin disease (LSD) is a vector-borne infection caused by the poxvirus lumpy skin disease virus (LSDV) and is a serious disease of cattle, water buffalo, and banteng. While the disease has never occurred in Australia, it is regarded as a growing threat to the Australian cattle industry as there is on-going spread of the disease throughout Asia. The development of geospatial decision support tools, such as spatial epidemiological modelling, may assist in assessing areas at greater risk of this threat. To guide the design of disease modelling approaches to support future risk-based surveillance, existing LSDV epidemiological models need to be evaluated. In this study, we performed a literature review to evaluate existing LSDV epidemiological models, identify key risk factors for introduction and spread of LSDV, and consider previously adopted control strategies. The PRISMA guidelines were used to establish the processes for article selection and information extraction, and the PICO process was used to formulate search terms. From studies that met our inclusion criteria, we extracted information on LSDV epidemiological model structure and parameterisation, risk factors for LSDV transmission and spread, and biosecurity control strategies. The literature search retrieved a total of 402 articles from four databases, of which 68 were identified for inclusion in this review following screening. Of the 68 articles reviewed, 47 explored risk factors associated with LSDV transmission and spread, four explored risk factors of LSDV introduction, four explored existing surveillance strategies in LSD-free countries, and 14 presented epidemiological models. Our findings indicate that there are various risk factors for LSDV transmission in LSD endemic countries, including long-distance airborne movement of infected vectors such as stable flies and cattle movement between countries over land borders. Key risk factors for LSDV spread in LSD endemic countries include physical environmental characteristics, weather conditions, and population distributions of livestock and vectors. Our results indicate that while a variety of modelling studies have been conducted, the majority of studies experimentally explored LSD transmission mechanisms in vectors and cattle. Spatial and spatio-temporal models have primarily been developed for LSD endemic countries and focus on the spread of the disease in terms of environmental factors in relation to previous LSD events. There were very few studies on LSD-free countries, and these only focussed on risk of LSD introduction through specific entry pathways. This review did not identify any literature exploring the risk of spread of LSDV following introduction in LSD-free countries or geospatial modelling of the suitability of LSD-free countries for LSDV incursions. In conjunction with the risk parameters and models described in the identified literature, there is need to consider a wide range of risk factors specific to Australia to inform the design of risk-based surveillance for LSD in Australia.

Clinical presentation and outcome of enteric fever in adult patients with cancer: a perspective from Pakistan.

Introduction. Enteric fever is a significant health concern in endemic countries. While extensive research has been conducted to understand its presentation and outcomes in non-cancer patients, limited data exist on its impact on cancer patients. This descriptive study aims to investigate the clinical presentation and outcome in cancer patients. Methodology. This retrospective observational study analysed 90 adult cancer patients from a single centre in Pakistan from January 2017 to December 2022. Inclusion criteria involved documented blood culture infections with Salmonella typhi or paratyphi A, B, or C. We examined clinical presentation, laboratory parameters, antimicrobial resistance, complications, and outcomes. Additionally, we explored the effects of chemotherapy, comorbidities, type of malignancy, and patient age on complications and mortality. Results. Salmonella typhi was the most prevalent organism (72.2 %), followed by Salmonella paratyphi A (22.2 %) and B (5.5 %). Variably-resistant isolates constituted 51.5 %, multi-drug resistant (MDR) isolates accounted for 20 %, extensively drug-resistant (XDR) for 14.4 % and ESBL-producers for 15.5 %, of all enteric fever infections. Enteric fever-associated complications were observed in 21.1 % of cases. Chemotherapy in the preceding month did not affect mortality, nor did age, gender, or malignancy type. However, comorbidities were statistically significant for mortality (p-value 0.03). A total of 8.8 % of patients required ICU care, and the all-cause 30 day mortality rate was 13.3 % Conclusion. Enteric fever remains prevalent in our geographical region. Unlike non-typhoidal Salmonella (NTS), enteric fever does not behave differently in an immunocompromised population, including cancer patients.

Tuberculous meningitis causing holocord longitudinally extensive transverse myelitis

ABSTRACT Longitudinally extensive transverse myelitis (LETM) is a neurological entity with characteristic inflammatory lesions in ≥3 vertebral segments of the spinal cord. It is most commonly associated with neuromyelitis optica spectrum disorder. Other causes include infections, autoimmune disorders, and neoplasms. Tuberculosis has been reported as a cause of LETM in few case reports. However, tuberculous meningitis (TBM) as a cause of LETM is extremely rare, more so with involvement of the complete spine cord from the brainstem to the conus medullaris. A 65-year-old female was admitted to our hospital with sudden-onset tetraplegia and sensory, bowel, and bladder involvement. With no significant past history, mild meningeal signs, and normal metabolic profile, cerebrospinal fluid analysis was done revealing polymerase chain reaction test positive for Mycobacterium tuberculosis. Magnetic resonance imaging of the spine was suggestive of complete spinal cord edema extending from the brainstem to the level of conus medullaris without skip lesions. A final impression of holocord LETM caused by TBM was suggested after ruling out other causes. The case highlights TBM as a potential cause of LETM especially in endemic countries, especially Asian and African countries, more so with holocord involvement without skip lesions.

Profile of metacaspase gene expression in Plasmodium vivax field isolates from the Brazilian Amazon

BackgroundMetacaspases comprise a family of cysteine proteases implicated in both cell death and cell differentiation of protists that has been considered a potential drug target for protozoan parasites. However, the biology of metacaspases in Plasmodium vivax − the second most prevalent and most widespread human malaria parasite worldwide, whose occurrence of chemoresistance has been reported in many endemic countries, remains largely unexplored. Therefore, the present study aimed to address, for the first time, the expression pattern of metacaspases in P. vivax parasites.Methods and resultsP. vivax blood-stage parasites were obtained from malaria patients in the Brazilian Amazon and the expression of the three putative P. vivax metacaspases (PvMCA1-3) was detected in all isolates by quantitative PCR assay. Of note, the expression levels of each PvMCA varied noticeably across isolates, which presented different frequencies of parasite forms, supporting that PvMCAs may be expressed in a stage-specific manner as previously shown in P. falciparum.ConclusionThe detection of metacaspases in P. vivax blood-stage parasites reported herein, allows the inclusion of these proteases as a potential candidate drug target for vivax malaria, while further investigations are still required to evaluate the activity, role and essentiality of metacaspases in P. vivax biology.

Environmental Surveillance of Poliovirus and Non-polio Enteroviruses in Iran, 2017-2023: First Report of Imported Wild Poliovirus Type 1 Since 2000.

In Iran, which is at high risk of the Wild Poliovirus (WPV) and Vaccine-Derived Poliovirus (VDPV) importation due to its neighborhood with two polio endemic countries, Pakistan and Afghanistan, Environmental Surveillance (ES) was established in November 2017. Sistan-Balouchestan province was chosen for the ES due to its vicinity with Pakistan and Afghanistan. Five sewage collection sites in 4 cities (Zahedan, Zabol, Chabahar and Konarak) were selected in the high-risk areas. Since the establishment of ES in November 2017 till the end of 2023, 364 sewage specimens were collected and analyzed. The ES detected polioviruses which have the highest significance for polio eradication program, that is, Wild Poliovirus type 1 (WPV1) and Poliovirus type 2 (PV2). In April and May 2019, three of 364 (0.8%) sewage specimens from Konarak were positive for imported WPV1. According to phylogenetic analysis, they were highly related to WPV1 circulating in Karachi (Sindh province) in Pakistan. PV2 was also detected in 5.7% (21/364) of the sewage specimens, most of which proved to be imported from the neighboring countries. Of 21 isolated PV2s, 7 were VDPV2, of which 5 proved to be imported from the neighboring countries as there was VDPV2 circulating in Pakistan at the time of sampling, and 2 were ambiguous VDPVs (aVDPV) with unknown source. According to the findings of this study, as long as WPV1 and VDPV2 outbreaks are detected in Iran's neighboring countries, there is a definite need for continuation and expansion of the environmental surveillance.

Detection of novel Plasmodium falciparum coronin gene mutations in a recrudescent ACT-treated patient in South-Western Nigeria.

Routine surveillance for antimalarial drug resistance is critical to sustaining the efficacy of artemisinin-based Combination Therapies (ACTs). Plasmodium falciparum kelch-13 (Pfkelch-13) and non-Pfkelch-13 artemisinin (ART) resistance-associated mutations are uncommon in Africa. We investigated polymorphisms in Plasmodium falciparum actin-binding protein (Pfcoronin) associated with in vivo reduced sensitivity to ART in Nigeria. Fifty-two P. falciparum malaria subjects who met the inclusion criteria were followed up in a 28-day therapeutic efficacy study of artemether-lumefantrine in Lagos, Nigeria. Parasite detection was done by microscopy and molecular diagnostic approaches involving PCR amplification of genes for Pf18S rRNA, varATS, telomere-associated repetitive elements-2 (TARE-2). Pfcoronin and Pfkelch-13 genes were sequenced bi-directionally while clonality of infections was determined using 12 neutral P. falciparum microsatellite loci and msp2 analyses. Antimalarial drugs (sulfadoxine-pyrimethamine, amodiaquine, chloroquine and some quinolones) resistance variants (DHFR_51, DHFR_59, DHFR_108, DHFR_164, MDR1_86, MDR1_184, DHPS_581 and DHPS_613) were genotyped by high-resolution melting (HRM) analysis. A total of 7 (26.92%) cases were identified either as early treatment failure, late parasitological failure or late clinical failure. Of the four post-treatment infections identified as recrudescence by msp2 genotypes, only one was classified as recrudescence by multilocus microsatellites genotyping. Microsatellite analysis revealed no significant difference in the mean allelic diversity, He, (P = 0.19, Mann-Whitney test). Allele sizes and frequency per locus implicated one isolate. Genetic analysis of this isolate identified two new Pfcoronin SNVs (I68G and L173F) in addition to the P76S earlier reported. Linkage-Disequilibrium as a standardized association index, IAS, between multiple P. falciparum loci revealed significant LD (IAS = 0.2865, P=0.02, Monte-Carlo simulation) around the neutral microsatellite loci. The pfdhfr/pfdhps/pfmdr1 drug resistance-associated haplotypes combinations, (108T/N/51I/164L/59R/581G/86Y/184F), were observed in two samples. Pfcoronin mutations identified in this study, with potential to impact parasite clearance, may guide investigations on emerging ART tolerance in Nigeria, and West African endemic countries.

Prevalence, Associated Factors and Treatment Outcomes of Laboratory-confirmed Pregnancy Malaria at Antenatal Care in Three Healthcare Facilities of Douala, Cameroon

Pregnancy malaria is a life-threatening condition to the mother, the fetus and the newborn. Since the implementation of the World Health Organization’s recommendations of specific malaria control strategies to pregnant women in malaria endemic countries, evaluation studies are needed to assess the prevalence of malaria in pregnancy. This cross-sectional prospective study was therefore set to determine the prevalence and associated factors as well as the treatment outcomes of Plasmodium infection among pregnant women attending antenatal care in three hospitals of Douala in Cameroon.
 Each volunteered pregnant woman received for antenatal care was questioned according to the study questionnaire to collect sociodemographic data, use of malaria prevention tools and pregnancy history. Then a laboratory test was carried for Plasmodium detection in the peripheral blood using microscopy and a HRP2-based rapid diagnostic test. Plasmodium carrying pregnant women were treated according to the national malaria program scheme followed by post-treatment follow-up. Data were processed and analyzed using SPSS.20 software. Association of Plasmodium infection with risk factors was analyzed as univariate using Pearson Chi-square and Fisher Exact tests considering a P-value < 0.05 as statistically significant.
 A total of 487 pregnant women aged between 18 years and 42 years were included in the study. The prevalence of Plasmodium infection was 3.5% and 4.3% by malaria rapid diagnostic test and microscopy respectively. Only Plasmodium falciparum asexual stage was detected. Parasite loads were low. Factors associated with Plasmodium falciparum higher prevalence were being less than 21 years old (0.02), not sleeping under mosquitoe net daily (p=0.04) and having fever during the pregnancy (p=0.04). Parenteral treatment with either artesunate, artemether or quinine sulfate showed good efficacy.
 Conclusion: Pregnant women attending the antenatal cares harbored low Plasmodium infection prevalence and loads. Being of young age, not sleeping under mosquitoe bednet daily and having fever during the pregnancy were predictive Plasmodium falciparum. Plasmodium infected pregnant women were successfully treated with antimalarial medications recommended by the national Ministry of Public Health. The authors recommend increasing efforts by health authorities to strengthen malaria prevention in pregnant women through more adherence to sleeping under ITNs daily and taking IPT-sp as well as systematic detection of Plasmodium infection at each antenatal visit.

Immunogenic profile of a plant-produced nonavalent African horse sickness viral protein 2 (VP2) vaccine in IFNAR-/- mice.

A safe, highly immunogenic multivalent vaccine to protect against all nine serotypes of African horse sickness virus (AHSV), will revolutionise the AHS vaccine industry in endemic countries and beyond. Plant-produced AHS virus-like particles (VLPs) and soluble viral protein 2 (VP2) vaccine candidates were developed that have the potential to protect against all nine serotypes but can equally well be formulated as mono- and bi-valent formulations for localised outbreaks of specific serotypes. In the first interferon α/β receptor knock-out (IFNAR-/-) mice trial conducted, a nine-serotype (nonavalent) vaccine administered as two pentavalent (5 μg per serotype) vaccines (VLP/VP2 combination or exclusively VP2), were directly compared to the commercially available AHS live attenuated vaccine. In a follow up trial, mice were vaccinated with an adjuvanted nine-serotype multivalent VP2 vaccine in a prime boost strategy and resulted in the desired neutralising antibody titres of 1:320, previously demonstrated to confer protective immunity in IFNAR-/- mice. In addition, the plant-produced VP2 vaccine performed favourably when compared to the commercial vaccine. Here we provide compelling data for a nonavalent VP2-based vaccine candidate, with the VP2 from each serotype being antigenically distinguishable based on LC-MS/MS and ELISA data. This is the first preclinical trial demonstrating the ability of an adjuvanted nonavalent cocktail of soluble, plant-expressed AHS VP2 proteins administered in a prime-boost strategy eliciting high antibody titres against all 9 AHSV serotypes. Furthermore, elevated T helper cells 2 (Th2) and Th1, indicative of humoral and cell-mediated memory T cell immune responses, respectively, were detected in mouse serum collected 14 days after the multivalent prime-boost vaccination. Both Th2 and Th1 may play a role to confer protective immunity. These preclinical immunogenicity studies paved the way to test the safety and protective efficacy of the plant-produced nonavalent VP2 vaccine candidate in the target animals, horses.

\'Yes! We can end TB’ the theme of the world tuberculosis day 2024: A commitment to fight the oldest known infectious disease from the world

Tuberculosis is a constant issue related to public health. The disease is highly infectious, and about one-fourth of the global population is presumed to be infected. The efforts for tuberculosis control are in full swing, especially in the endemic countries. The World Tuberculosis Day was celebrated on March 24, 2024; however, the theme of the last year, i.e., 'Yes! We can end TB', was continued for 2024. The theme justifies the commitment of stakeholders and policymakers to a sustained effort to eliminate tuberculosis.

Potential Pathogenicity and Genetic Characteristics of a Live-Attenuated Classical Swine Fever Virus Vaccine Derivative Variant

Classical swine fever (CSF), caused by CSF virus (CSFV), is a highly contagious disease affecting pigs and causing massive pig production losses with severe global economic recession. The immunization of live-attenuated vaccines is still one of the key measures to CSFV management in endemic countries. However, there are also strong controversies about the usage of live-attenuated vaccines, particularly in pregnant sows and young pigs, such as in Europe, where domestic pigs are routinely not vaccinated until severe outbreaks occur. Here, we report a CSF outbreak in a pig farm in China, which affected more than 90% of the delivery sows and led to ∼45% birth loss. Surprisingly, phylogenetic analysis showed that the CSFV isolate (named CSFV/HeNLY2022, GenBank No. OR195698) was clustered into subgenotype 1.1a, closely together with the live-attenuated vaccine strains. Further genomic analysis also revealed that the isolate CSFV/HeNLY2022 shared the highest nucleotide identity of 99.7% with the C/HVRI vaccine strain (C-strain, GenBank No. AY805221). Moreover, compared to the C/HVRI strain, a total of eight amino acid mutations, distributed in Erns (H436thY and S476thR), E1 (T502thI and P581thT), E2 (M979thK and A1061thS), NS5A (A2980thT), and NS5B (I3818thM), were characterized in the CSFV/HeNLY2022 isolate. Our results suggested that the CSF outbreak was most likely caused by the live-attenuated CSFV vaccine or its derivative. It raises concern that the unscientific application of CSFV vaccines could potentially lead to CSFV spread in pigs. It is needed to perform a more rigorous evaluation of the safety of the C-strain-derived vaccines in combination with other different live-attenuated vaccines.

Helminth exposure and immune response to the two-dose heterologous Ad26.ZEBOV, MVA-BN-Filo Ebola vaccine regimen.

The exposure to parasites may influence the immune response to vaccines in endemic African countries. In this study, we aimed to assess the association between helminth exposure to the most prevalent parasitic infections, schistosomiasis, soil transmitted helminths infection and filariasis, and the Ebola virus glycoprotein (EBOV GP) antibody concentration in response to vaccination with the Ad26.ZEBOV, MVA-BN-Filo vaccine regimen in African and European participants using samples obtained from three international clinical trials. We conducted a study in a subset of participants in the EBL2001, EBL2002 and EBL3001 clinical trials that evaluated the Ad26.ZEBOV, MVA-BN-Filo vaccine regimen against EVD in children, adolescents and adults from the United Kingdom, France, Burkina Faso, Cote d'Ivoire, Kenya, Uganda and Sierra Leone. Immune markers of helminth exposure at baseline were evaluated by ELISA with three commercial kits which detect IgG antibodies against schistosome, filarial and Strongyloides antigens. Luminex technology was used to measure inflammatory and activation markers, and Th1/Th2/Th17 cytokines at baseline. The association between binding IgG antibodies specific to EBOV GP (measured on day 21 post-dose 2 and on Day 365 after the first dose respectively), and helminth exposure at baseline was evaluated using a multivariable linear regression model adjusted for age and study group. Seventy-eight (21.3%) of the 367 participants included in the study had at least one helminth positive ELISA test at baseline, with differences of prevalence between studies and an increased prevalence with age. The most frequently detected antibodies were those to Schistosoma mansoni (10.9%), followed by Acanthocheilonema viteae (9%) and then Strongyloides ratti (7.9%). Among the 41 immunological analytes tested, five were significantly (p < .003) lower in participants with at least one positive helminth ELISA test result: CCL2/MCP1, FGFbasic, IL-7, IL-13 and CCL11/Eotaxin compared to participants with negative helminth ELISA tests. No significant association was found with EBOV-GP specific antibody concentration at 21 days post-dose 2, or at 365 days post-dose 1, adjusted for age group, study, and the presence of any helminth antibodies at baseline. No clear association was found between immune markers of helminth exposure as measured by ELISA and post-vaccination response to the Ebola Ad26.ZEBOV/ MVA-BN-Filo vaccine regimen. NCT02416453, NCT02564523, NCT02509494. ClinicalTrials.gov.