Concurrent circulation of dengue serotype 1, 2 and 3 among acute febrile patients in Cameroon

Acute febrile patients presenting at hospitals in Douala, Cameroon between July and December 2020, were screened for dengue infections using RT-PCR on fragments of the 5’ and 3’ UTR genomic regions. In total, 12.8% (41/320) of cases examined were positive for dengue. Dengue virus 3 (DENV-3) was the most common serotype found (68.3%), followed by DENV-2 (19.5%) and DENV-1 (4.9%). Co-infections of DENV-3 and DENV-2 were found in 3 cases. Jaundice and headache were the most frequent clinical signs associated with infection and 56% (23/41) of the cases were co-infections with malaria. Phylogenetic analysis of the envelope gene identified DENV-1 as belonging to genotype V, DENV-2 to genotype II and DENV-3 to genotype III. The simultaneous occurrence of three serotypes in Douala reveals dengue as a serious public health threat for Cameroon and highlights the need for further epidemiological studies in the major cities of this region.

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Concurrent circulation of dengue serotype 1, 2 and 3 among acute febrile patients in Cameroon

10.1101/2021.05.10.21256254 ◽

2021 ◽

Author(s):

Huguette Dorine SIMO TCHETGNA ◽

Francine SADO YOUSSEU ◽

Basile Kamgang ◽

Armel TEDJOU ◽

Philip McCall ◽

...

Keyword(s):

Clinical Signs ◽

Epidemiological Studies ◽

Simultaneous Occurrence ◽

Envelope Gene ◽

Rt Pcr ◽

Genotype Iii ◽

Serotype 1 ◽

Genomic Regions ◽

Genotype V ◽

Genotype Ii

Acute febrile patients presenting at hospitals in Douala, Cameroon between July and December 2020, were screened for dengue infections using RT-PCR on fragments of the 5 and 3 UTR genomic regions. In total, 12.8% (41/320) of cases examined were positive for dengue. Dengue virus 3 (DENV-3) was the most common serotype found (68.3%), followed by DENV-2 (19.5%) and DENV-1 (4.9%). Co-infections of DENV-3 and DENV-2 were found in 3 cases. Jaundice and headache were the most frequent clinical signs associated with infection and 176 cases (55%) were co-infections with malaria. Phylogenetic analysis of the envelope gene identified DENV-1 as belonging to genotype V, DENV-2 to genotype II and DENV-3 to genotype III. The simultaneous occurrence of three serotypes in Douala reveals dengue as a serious public health threat for Cameroon and highlights the need for further epidemiological studies in the major cities of this region.

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Phylogeny of Mycobacterium avium strains inferred from glycopeptidolipid biosynthesis pathway genes

Microbiology ◽

10.1099/mic.0.27007-0 ◽

2004 ◽

Vol 150 (6) ◽

pp. 1699-1706 ◽

Cited By ~ 8

Author(s):

Elzbieta Krzywinska ◽

Jaroslaw Krzywinski ◽

Jeffrey S. Schorey

Keyword(s):

Mycobacterium Avium ◽

Epidemiological Studies ◽

Genomic Region ◽

Opportunistic Pathogens ◽

Apparent Lack ◽

Alternative Placement ◽

Multiple Origins ◽

Serotype 1 ◽

History Of ◽

Genomic Regions

The Mycobacterium avium complex (MAC) encompasses two species, M. avium and Mycobacterium intracellulare, which are opportunistic pathogens of humans and animals. The standard method of MAC strain differentiation is serotyping based on a variation in the antigenic glycopeptidolipid (GPL) composition. To elucidate the relationships among M. avium serotypes a phylogenetic analysis of 13 reference and clinical M. avium strains from 8 serotypes was performed using as markers two genomic regions (890 bp of the gtfB gene and 2150 bp spanning the rtfA–mtfC genes) which are associated with the strains' serological properties. Strains belonging to three other known M. avium serotypes were not included in the phylogeny inference due to apparent lack of the marker sequences in their genomes, as revealed by PCR and Southern blot analysis. These studies suggest that serotypes prevalent in AIDS patients have multiple origins. In trees inferred from both markers, serotype 1 strains, known to have the simplest and shortest GPLs among all other serotypes, were polyphyletic. Likewise, comparisons of the inferred phylogenies with the molecular typing results imply that the existing tools used in epidemiological studies may be poor estimators of M. avium strain relatedness. Additionally, trees inferred from each marker had significantly incongruent topologies due to a well supported alternative placement of strain 2151, suggesting a complex evolutionary history of this genomic region.

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Answer to dengue and chikungunya: specific antiviral therapy

International Journal of Advances in Medicine ◽

10.18203/2349-3933.ijam20171069 ◽

2017 ◽

Vol 4 (2) ◽

pp. 603

Author(s):

Mrinmay Ghosh

Keyword(s):

Clinical Signs ◽

Maculopapular Rash ◽

Laboratory Diagnosis ◽

Viral Disease ◽

Sudden Onset ◽

Rt Pcr ◽

Gastrointestinal Lesions ◽

Macular Rash ◽

Serotype 1 ◽

Specific Antiviral Therapy

Dengue is probably the most important arthropod borne viral disease worldwide, with 50-100 million infections occurring per year. Year-round transmission of dengue viruses of serotype 1-4 is prevalent globally. Vectors are Aedes aegypti and Aedes albopictus. Laboratory diagnosis by ELISA for IgM or RT-PCR, Incubation period 4-7days, sudden onset of fever, frontal headache, retro orbital pain, back pain with severe myalgia, a transient macular rash on the first day, lymphadenopathy, palatal vesicles, scleral infections. Illness may last a week with clinical signs; anorexia, nausea, vomiting, marked cutaneous maculopapular rash on trunks spreading to extremities and face on defervescences on days 3-5. Epistaxis, scattered petechiae and preexisting gastrointestinal lesions may bleed during acute phase.

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Detection of diarrhoea associated rotavirus and co-infection with diarrhoeagenic pathogens in the Littoral region of Cameroon using ELISA, RT-PCR and Luminex xTAG GPP assays

BMC Infectious Diseases ◽

10.1186/s12879-021-06318-x ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Rahinatou N. Ghapoutsa ◽

Maurice Boda ◽

Rashi Gautam ◽

Valantine Ngum Ndze ◽

Akongnwi E. Mugyia ◽

...

Keyword(s):

Demographic Data ◽

Laboratory Diagnosis ◽

Epidemiological Studies ◽

Sub Saharan Africa ◽

Rt Pcr ◽

Mortality And Morbidity ◽

Vaccine Introduction ◽

Littoral Region ◽

Rotavirus Vaccines ◽

The Impact

Abstract Background Despite the global roll-out of rotavirus vaccines (RotaTeq/Rotarix / ROTAVAC/Rotasiil), mortality and morbidity due to group A rotavirus (RVA) remains high in sub-Saharan Africa, causing 104,000 deaths and 600,000 hospitalizations yearly. In Cameroon, Rotarix™ was introduced in March 2014, but, routine laboratory diagnosis of rotavirus infection is not yet a common practice, and vaccine effectiveness studies to determine the impact of vaccine introduction have not been done. Thus, studies examining RVA prevalence post vaccine introduction are needed. The study aim was to determine RVA prevalence in severe diarrhoea cases in Littoral region, Cameroon and investigate the role of other diarrheagenic pathogens in RVA-positive cases. Methods We carried out a study among hospitalized children < 5 years of age, presenting with acute gastroenteritis in selected hospitals of the Littoral region of Cameroon, from May 2015 to April 2016. Diarrheic stool samples and socio-demographic data including immunization and breastfeeding status were collected from these participating children. Samples were screened by ELISA (ProSpecT™ Rotavirus) for detection of RVA antigen and by gel-based RT-PCR for detection of the VP6 gene. Co-infection was assessed by multiplexed molecular detection of diarrheal pathogens using the Luminex xTAG GPP assay. Results The ELISA assay detected RVA antigen in 54.6% (71/130) of specimens, with 45, positive by VP6 RT-PCR and 54, positive using Luminex xTAG GPP. Luminex GPP was able to detect all 45 VP6 RT-PCR positive samples. Co-infections were found in 63.0% (34/54) of Luminex positive RVA infections, with Shigella (35.3%; 12/34) and ETEC (29.4%; 10/34) detected frequently. Of the 71 ELISA positive RVA cases, 57.8% (41/71) were fully vaccinated, receiving two doses of Rotarix. Conclusion This study provides insight on RVA prevalence in Cameroon, which could be useful for post-vaccine epidemiological studies, highlights higher than expected RVA prevalence in vaccinated children hospitalized for diarrhoea and provides the trend of RVA co-infection with other enteric pathogens. RVA genotyping is needed to determine circulating rotavirus genotypes in Cameroon, including those causing disease in vaccinated children.

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Relationship between Autism Spectrum Disorder and Pesticides: A Systematic Review of Human and Preclinical Models

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18105190 ◽

2021 ◽

Vol 18 (10) ◽

pp. 5190

Author(s):

Judit Biosca-Brull ◽

Cristian Pérez-Fernández ◽

Santiago Mora ◽

Beatriz Carrillo ◽

Helena Pinos ◽

...

Keyword(s):

Systematic Review ◽

Autism Spectrum Disorder ◽

Experimental Studies ◽

Clinical Signs ◽

Epidemiological Studies ◽

Autism Spectrum ◽

Spectrum Disorder ◽

Preclinical Studies ◽

Preclinical Models ◽

Gestational Exposure

Autism spectrum disorder (ASD) is a complex set of neurodevelopmental pathologies characterized by impoverished social and communicative abilities and stereotyped behaviors. Although its genetic basis is unquestionable, the involvement of environmental factors such as exposure to pesticides has also been proposed. Despite the systematic analyses of this relationship in humans, there are no specific reviews including both human and preclinical models. The present systematic review summarizes, analyzes, and discusses recent advances in preclinical and epidemiological studies. We included 45 human and 16 preclinical studies. These studies focused on Organophosphates (OP), Organochlorine (OC), Pyrethroid (PT), Neonicotinoid (NN), Carbamate (CM), and mixed exposures. Preclinical studies, where the OP Chlorpyrifos (CPF) compound is the one most studied, pointed to an association between gestational exposure and increased ASD-like behaviors, although the data are inconclusive with regard to other ages or pesticides. Studies in humans focused on prenatal exposure to OP and OC agents, and report cognitive and behavioral alterations related to ASD symptomatology. The results of both suggest that gestational exposure to certain OP agents could be linked to the clinical signs of ASD. Future experimental studies should focus on extending the analysis of ASD-like behaviors in preclinical models and include exposure patterns similar to those observed in human studies.

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A New Multiplex Real-Time RT-PCR for Simultaneous Detection and Differentiation of Avian Bornaviruses

Viruses ◽

10.3390/v13071358 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1358

Author(s):

Brigitte Sigrist ◽

Jessica Geers ◽

Sarah Albini ◽

Dennis Rubbenstroth ◽

Nina Wolfrum

Keyword(s):

Real Time ◽

Simultaneous Detection ◽

Epidemiological Studies ◽

Virus Species ◽

Rt Pcr ◽

P Gene ◽

Field Samples ◽

Causative Agents ◽

Species Specific ◽

Proventricular Dilatation Disease

Avian bornaviruses were first described in 2008 as the causative agents of proventricular dilatation disease (PDD) in parrots and their relatives (Psittaciformes). To date, 15 genetically highly diverse avian bornaviruses covering at least five viral species have been discovered in different bird orders. Currently, the primary diagnostic tool is the detection of viral RNA by conventional or real-time RT-PCR (rRT-PCR). One of the drawbacks of this is the usage of either specific assays, allowing the detection of one particular virus, or of assays with a broad detection spectrum, which, however, do not allow for the simultaneous specification of the detected virus. To facilitate the simultaneous detection and specification of avian bornaviruses, a multiplex real-time RT-PCR assay was developed. Whole-genome sequences of various bornaviruses were aligned. Primers were designed to recognize conserved regions within the overlapping X/P gene and probes were selected to detect virus species-specific regions within the target region. The optimization of the assay resulted in the sensitive and specific detection of bornaviruses of Psittaciformes, Passeriformes, and aquatic birds. Finally, the new rRT-PCR was successfully employed to detect avian bornaviruses in field samples from various avian species. This assay will serve as powerful tool in epidemiological studies and will improve avian bornavirus detection.

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Live Attenuated African Swine Fever Viruses as Ideal Tools to Dissect the Mechanisms Involved in Cross-Protection

Viruses ◽

10.3390/v12121474 ◽

2020 ◽

Vol 12 (12) ◽

pp. 1474

Author(s):

Elisabeth Lopez ◽

Juanita van Heerden ◽

Laia Bosch-Camós ◽

Francesc Accensi ◽

Maria Jesus Navas ◽

...

Keyword(s):

Vaccine Development ◽

African Swine Fever Virus ◽

Virulent Strain ◽

Sequence Similarity ◽

Clinical Signs ◽

African Swine Fever ◽

Cross Protection ◽

Sub Saharan Africa ◽

Genotype I ◽

Genotype Ii

African swine fever (ASF) has become the major threat for the global swine industry. Furthermore, the epidemiological situation of African swine fever virus (ASFV) in some endemic regions of Sub-Saharan Africa is worse than ever, with multiple virus strains and genotypes currently circulating in a given area. Despite the recent advances on ASF vaccine development, there are no commercial vaccines yet, and most of the promising vaccine prototypes available today have been specifically designed to fight the genotype II strains currently circulating in Europe, Asia, and Oceania. Previous results from our laboratory have demonstrated the ability of BA71∆CD2, a recombinant LAV lacking CD2v, to confer protection against homologous (BA71) and heterologous genotype I (E75) and genotype II (Georgia2007/01) ASFV strains, both belonging to same clade (clade C). Here, we extend these results using BA71∆CD2 as a tool trying to understand ASFV cross-protection, using phylogenetically distant ASFV strains. We first observed that five out of six (83.3%) of the pigs immunized once with 106 PFU of BA71∆CD2 survived the tick-bite challenge using Ornithodoros sp. soft ticks naturally infected with RSA/11/2017 strain (genotype XIX, clade D). Second, only two out of six (33.3%) survived the challenge with Ken06.Bus (genotype IX, clade A), which is phylogenetically more distant to BA71∆CD2 than the RSA/11/2017 strain. On the other hand, homologous prime-boosting with BA71∆CD2 only improved the survival rate to 50% after Ken06.Bus challenge, all suffering mild ASF-compatible clinical signs, while 100% of the pigs immunized with BA71∆CD2 and boosted with the parental BA71 virulent strain survived the lethal challenge with Ken06.Bus, without almost no clinical signs of the disease. Our results confirm that cross-protection is a multifactorial phenomenon that not only depends on sequence similarity. We believe that understanding this complex phenomenon will be useful for designing future vaccines for ASF-endemic areas.

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Metabolomic Signature in Sera of Multiple Sclerosis Patients during Pregnancy

International Journal of Molecular Sciences ◽

10.3390/ijms19113589 ◽

2018 ◽

Vol 19 (11) ◽

pp. 3589 ◽

Cited By ~ 7

Author(s):

Claudia Rossi ◽

Ilaria Cicalini ◽

Mirco Zucchelli ◽

Maria di Ioia ◽

Marco Onofrj ◽

...

Keyword(s):

Multiple Sclerosis ◽

Clinical Signs ◽

Female Gender ◽

Epidemiological Studies ◽

Mass Spectrometry Analysis ◽

Spectrometry Analysis ◽

Hormonal Fluctuations ◽

The Central Nervous System ◽

Multiple Sclerosis Patients

Multiple sclerosis (MuS) is an autoimmune disease of the central nervous system characterized by neuroinflammation, neurodegeneration, and degradation of the myelin sheath. Epidemiological studies have shown that the female gender is more susceptible than the male gender to MuS development, with a female-to-male ratio of 2:1. Despite this high onset, women have a better prognosis than men, and the frequency of the relapsing phase decreases during pregnancy, while it increases soon after birth. Therefore, it is interesting to investigate hormonal fluctuations during pregnancy and whether they correlate with metabolic signatures. To gain a deeper inside into the biochemical mechanism of such a multifactorial disease, we adopted targeted metabolomics approaches for the determination of many serum metabolites in 12 pregnant women affected by MuS by mass spectrometry analysis. Our data show a characteristic hormonal fluctuation for estrogens and progesterone, as expected. They also highlight other interesting hormonal alterations for cortisol, corticosterone, 11-deoxycortisol, 4-androstene-3,17-dione, testosterone, and 17α-hydroxyprogesterone. Furthermore, a negative correlation with progesterone levels was observed for amino acids and for acylcarnitines, while an imbalance of different sphingolipids pathways was found during pregnancy. In conclusion, these data are in agreement with the characteristic clinical signs of MuS patients during pregnancy and, if confirmed, they may add an important tessera in the complex mosaic of maternal neuroprotection.

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Recent advances in the laboratory diagnosis of peste des petits ruminants

Medycyna Weterynaryjna ◽

10.21521/mw.6536 ◽

2021 ◽

Vol 77 (05) ◽

pp. 226-231

Author(s):

WIESŁAW NIEDBALSKI ◽

ANDRZEJ FITZNER ◽

KRZYSZTOF BULENGER ◽

ANDRZEJ KĘSY

Keyword(s):

Reverse Transcription ◽

Animal Health ◽

Clinical Signs ◽

Small Ruminants ◽

Clinical Diagnostics ◽

Molecular Diagnostic ◽

Molecular Diagnostic Techniques ◽

Peste Des Petits Ruminants ◽

Rt Pcr ◽

Agar Gel

Peste des petits ruminants (PPR) is a highly contagious and economically important, viral disease of small ruminants caused by the peste des petits ruminants virus (PPRV), which belongs to the genus Morbilivirus in the family Paramyxoviridae. PPR control is achieved mostly through vaccination and/or slaughter of susceptible animals coupled with clinical or laboratory-based diagnosis. Since clinical signs of PPR are not disease-specific and clinical diagnostics is not reliable, it should be confirmed by laboratory testing. Laboratory confirmation of clinical suspicions is made by detection of PPRV in blood, swabs or post-mortem tissues through classical virus isolation (VI), agar gel immunodiffusion (AGID)/agar gel precipitation test (AGPT), counter-immunoelectrophoresis (CIE), immunoperoxidase test (IPT) or enzyme-linked immunosorbent (ELISA) assays. However, these conventional methods have been superseded by more rapid, sensitive and accurate molecular diagnostic techniques based on the amplification of parts of either nucleocapsid (N) or fusion (F) protein gene, such as RT-PCR, real-time RT-PCR, reverse transcription loop-mediated isothermal amplification (RT-LAMP), reverse transcription recombinase polymerase amplification (RT-RPA) and Oxford nanopore MinION technology. Although these molecular diagnostic assays are accurate, rapid and sensitive, they have to be performed in laboratory settings, and samples must be transported under appropriate conditions from the field to the laboratory, which can delay the confirmation of PPRV infection. The recently developed immunochromatographic lateral flow device (IC-LFD) assay can be used in the field (“pen-side”) without the need for expensive equipment, so a well-established laboratory is not required. The control and eventual eradication of PPR is now one of the top priorities for the Food and Agriculture Organization (FAO) and the World Organization for Animal Health (OIE). In 2015, the international community agreed on a global strategy for PPR eradication, setting 2030 as a target date for elimination of the disease

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Phylogenetic Characterization of Arboviruses in Patients Suffering from Acute Fever in Rondônia, Brazil

Viruses ◽

10.3390/v12080889 ◽

2020 ◽

Vol 12 (8) ◽

pp. 889

Author(s):

Jackson Alves da Silva Queiroz ◽

Luan Felipo Botelho-Souza ◽

Felipe Souza Nogueira-Lima ◽

Rita de Cássia Pontello Rampazzo ◽

Marco Aurélio Krieger ◽

...

Keyword(s):

Viral Load ◽

Phylogenetic Analyses ◽

Metropolitan Region ◽

Evolutionary Analysis ◽

Detectable Viral Load ◽

Conventional Pcr ◽

Serum Samples ◽

Phylogenetic Characterization ◽

Genotype V ◽

Genotype Ii

The purpose of the study was to classify, through phylogenetic analyses, the main arboviruses that have been isolated in the metropolitan region of Porto Velho, Rondônia, Brazil. Serum samples from patients with symptoms suggesting arboviruses were collected and tested by One Step RT-qPCR for Zika, Dengue (serotypes 1–4), Chikungunya, Mayaro and Oropouche viruses. Positive samples were amplified by conventional PCR and sequenced utilizing the Sanger method. The obtained sequences were aligned, and an evolutionary analysis was carried out using Bayesian inference. A total of 308 samples were tested. Of this total, 20 had a detectable viral load for Dengue, being detected DENV1 (18/20), co-infection DENV1 and DENV2 (1/20) and DENV4 (1/20). For Dengue serotype 3 and for the CHIKV, ZIKV, MAYV and OROV viruses, no individuals with a detectable viral load were found. A total of 9 of these samples were magnified by conventional PCR for sequencing. Of these, 6 were successfully sequenced and, according to the evolutionary profile, 5 corresponded to serotype DENV-1 genotype V, and 1 to serotype DENV-4 genotype II. In the study, we demonstrate co-circulation of the DENV-1 genotype V and the DENV-4 genotype II. Co-circulation of several DENV serotypes in the same city poses a risk to the population and is correlated with the increase of the most severe forms of the disease. Similarly, co-circulation of genetically distinct DENV and the occurrence of simultaneous infections can affect recombination events and lead to the emergence of more virulent isolates.

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