Single Infection Research Articles

Occurrence and Distribution of Major Cassava Pests and Diseases in Cultivated Cassava Varieties in Western Kenya.

Cassava is an important food crop in western Kenya, yet its production is challenged by pests and diseases that require routine monitoring to guide development and deployment of control strategies. Field surveys were conducted in 2022 and 2023 to determine the prevalence, incidence and severity of cassava mosaic disease (CMD) and cassava brown streak disease (CBSD), whitefly numbers and incidence of cassava green mite (CGM) in six counties of western Kenya. Details of the encountered cassava varieties were carefully recorded to determine the adoption of improved varieties. A total of 29 varieties were recorded, out of which 13 were improved, although the improved varieties were predominant in 60% of fields and the most widely grown variety was MM96/4271. The CMD incidence was higher in 2022 (26.4%) compared to 2023 (10.1%), although the proportion of CMD attributable to whitefly infection was greater (50.6%) in 2023 than in 2022 (18.0%). The CBSD incidence in 2022 was 6.4%, while in 2023 it was 4.1%. The CMD incidence was significantly lower (5.9%) for the improved varieties than it was for the local varieties (35.9%), although the CBSD incidence did not differ significantly between the improved (2.3%) and local varieties (9.7%). Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV) were both detected. Most infections were single CBSV infections (82.9%), followed by single UCBSV (34.3%) and coinfection with both viruses (16.7%). Whiteflies were more abundant in 2023, in which 28% of the fields had super-abundant populations of >100/plant, compared to 5% in 2022. KASP SNP genotyping designated 92.8% of the specimens as SSA-ECA for 2022, while it was 94.4% for 2023. The cassava green mite incidence was 65.4% in 2022 compared to 79.9% in 2023. This study demonstrates that cassava viruses, whiteflies and cassava green mites continue to be important constraints to cassava production in western Kenya, although the widespread cultivation of improved varieties is reducing the impact of cassava viruses. The more widespread application of high-quality seed delivery mechanisms could further enhance the management of these pests/diseases, coupled with wider application of IPM measures for whiteflies and mites.

Domestic dogs as reservoirs for African trypanosomiasis in Mambwe district, eastern Zambia

The control of African trypanosomiasis (AT) in Eastern and Southern Africa, including Zambia, faces huge challenges due to the involvement of wild and domestic animal reservoirs. Free-roaming dogs in wildlife-populated and tsetse-infested villages of Zambia’s Mambwe district are exposed to infectious tsetse bites. Consuming fresh raw game meat and bones further exacerbates their risk of contracting AT. We focus on the reservoir role of such dogs in maintaining and transmitting diverse species of trypanosomes that are infective to humans and livestock in Zambia’s Mambwe district. A cohort of 162 dogs was enrolled for follow-up at 3 different time points from June to December 2018 in selected villages of Malama, Mnkhanya, and Nsefu chiefdoms of Mambwe district, eastern Zambia. Blood and serum were screened for AT by microscopy, GM6 ELISA, PCR (ITS1 and SRA), and Sanger sequencing. Out of the 162 dogs in the cohort, 40 were lost to follow-up and only 122 remained traceable at the end of the study. GM6 ELISA detected Trypanosoma antibodies in 121 dogs (74.7%) and ITS1-PCR detected DNA involving single and mixed infections of T. congolense, T. brucei, and suspected T. simiae or T. godfreyi in 115 dogs (70.9%). The human-infective T. b. rhodesiense was detected by SRA PCR in 67 dogs (41.4%), and some sequence data that support the findings of this study have been deposited in the GenBank under accession numbers OL961811, OL961812, and OL961813. Our study demonstrates that the Trypanosoma reservoir community in Zambia is wider than was thought and includes domesticated dogs. As dogs are active carriers of human and livestock-infective trypanosomes, they pose a risk of transmitting AT in endemic villages of Mambwe district as they are neglected and left untreated. To fully bring AT under control, countries such as Zambia where the role of animal reservoirs is important, should not limit their prevention and treatment efforts to livestock (especially cattle) but also include dogs that play an integral part in most rural communities.

Trends in human papillomavirus infection and genotype distribution among males in Chongqing, China (2017-2022): an observational study.

This study aimed to investigate Human papillomavirus (HPV) infection and genotyping in men from Chongqing and analyze age-related trends to provide insights for HPV prevention and vaccination plans tailored for men in Chongqing, China. This study is an observational study. We investigated male patients who underwent HPV screening at two hospitals in Chongqing from 2017 to 2022, totaling 4,381 cases, aged 18 to 85. HPV genotyping was conducted using the Hybribio Rapid GenoArray kit. Among the 4,381 men, the overall HPV prevalence was 14.9%, peaking at 19.3% in 2022. Single HPV infection was 11.5%, and multiple infection was 3.4%. The most prevalent genotypes were HPV-52, HPV-16, and HPV-58. Single high-risk HPV infection peaked in the 36-45 age group, while multiple high-risk HPV infection decreased with age (P-trend < 0.01). Prevalence in the ≤ 25 age group was 3.7%. Single low-risk HPV infection also decreased with age (P-trend = 0.03). Genotypes covered by the nonavalent vaccine had the highest prevalence, increasing with age. Co-infection of HPV-16 with HPV-52 and HPV-58 was common. Single HPV infections were prevalent in cases of urethritis (30.8%), anogenital warts (36.4%), and genital warts (26.3%), while multiple HPV infections were significant in anogenital warts (18.2%). Single HPV infection was predominant in Chongqing, with HPV-52, HPV-16, HPV-58, HPV-53, and HPV-39 being the most prevalent genotypes. The prevalence of genotypes covered by the nonavalent vaccine increased with age. This study offers valuable insights for developing male-specific HPV prevention strategies in Chongqing.

Prevalence of Gastrointestinal Parasites of Poultry Chicken Slaughtered and Sold in Uyo Metropolis, Akwa Ibom State, Nigeria

Gastrointestinal parasites (GIP) are important biological enemies causing poor health in poultry, thereby causing significant reduction in harvest. This study was aimed to assess the prevalence of gastrointestinal parasites of poultry chickens slaughtered in Uyo, Akwa Ibom State. One hundred and fifty (150) intestinal contents of poultry chickens slaughtered were collected from poultry dressing units in market within Uyo metropolis and kept in polythene bags, and then transported to the Animal and Environmental Biology laboratory of the University of Uyo for analysis. The gizzard, small and large intestine and caeca were assessed for GIP. The method employed in this assessment was Direct Wet Mount following other standard methods. The parasites were analyses by microscopic examination of the fecal smears, thereafter identification of parasite. Five species were encountered in this study: Ascaris galli (32.76%) had the highest, followed by of Eimeria tenella (25.86%), Raillietina tetragona (16.39%) and Histomonas meleagridisis (16.39%). The least was recorded in Heterakis gallinarum (10.34%). Among the 67 (male) and 83 (female) samples, 34.38% and 65.62% respectively recorded positive. Ascaris galli, being the most prevalent was seen in 38 samples and Histomonas meleagridisis (the lowest) was seen in only 12 samples. &gt; 12 weeks age group recorded lowest prevalence (9.3%) while 8-12 weeks had highest (19.30%). This study reveals that 39.12% had single parasitic infection, while mixed had 60.94%. Based on these results, poultry in Uyo farms are affected with gastrointestinal parasitic infection. Therefore, it is recommended that farmer should improve upon their management skills and issues concerning hygiene.

Impact of multiple infections on risk of incident dementia according to subjective cognitive decline status: a nationwide population-based cohort study.

The interrelation between infections, subjective cognitive decline (SCD), and dementia development is recognized, but not fully understood. This study explored the combined effect of specific infections and SCD on the risk of dementia. To assess the influence of Helicobacter pylori, herpes simplex virus, varicella-zoster virus, and human papillomavirus on dementia risk in individuals with varying cognitive statuses, especially focusing on those with and without SCD. A cohort of 1,100,540 participants aged 66 years from the Korean National Health Insurance Service was divided into cognitively preserved (CP, n = 825,405) and SCD (n = 275,135) groups. This study analyzed the effects of single, dual, and triple infections on the risk of overall dementia, Alzheimer's disease (AD), and vascular dementia (VaD) using incidence rates and hazard ratios. The SCD group consistently showed a doubled risk of dementia, particularly AD, regardless of the number of infections. In the initial data, both the presence and number of infections, especially in the CP group, were associated with an increased dementia incidence and risk; however, this correlation disappeared after adjusting for covariates, hinting at a possible protective effect. Our findings emphasize that, while SCD is a steadfast risk factor for dementia, the role of infections is layered, subject to various influences, and requires more comprehensive exploration to fully understand their impact on dementia development.

A Retrospective Analysis of Four STI Pathogens in Obstetrics and Gynecological Patients in Hangzhou, China.

Among sexually transmitted infection (STI) pathogens, UU, CT, NG, and MG are very commonly detected. A retrospective study was conducted to analyze the clinical situations and laboratory data of patients in-fected with the four pathogens in Hangzhou city, Zhejiang Province, China. For this study, 4,716 female outpatients and inpatients of the Department of Obstetrics and Gynecology of Hangzhou Third People´s Hospital were randomly selected from January 2019 to December 2023. Multiple types of specimens were collected and four STI pathogens were detected. Data collection was taken from the hospital's electronic medical records and statistical analysis was processed with SPSS 25.0 software. In the past five years, year by year, the positive rate presented an increasing trend. Out of 4,716 patients, 2,931 were positive, and the positive rate was 62.15%. The positive rate of single infection was significantly higher than of co-infection (p < 0.05). The highest positive rate of all STI patients was found in the  20 age group, and the rate was significantly different between each age group (p < 0.05). Single infection with UU occurred significantly more often than with the other three pathogens (p < 0.05), and co-infection with UU and CT and UU, CT, and MG were significantly dominating (p < 0.05). Only three patients had an infection with all four pathogens, and it was extremely rare. The 21 - 30 and 31 - 40 age groups had high incidences of infection, with a significant difference compared with other age groups (p < 0.05). The positive rate shows an increasing trend in Hangzhou in the past five years. More single infection than co-infection and more younger patients were detected. Single infection with UU was dominant in all positive patients. The publicity and more screening testing items of STI for younger people should be strengthened in Hangzhou, and the people of Hangzhou should be made more aware that information technology is helpful in aiding the control of STI diseases.

Prevalence of Soil-Transmitted Helminthiasis and Its Association with Pediatric Diarrhea in Perobatang Village, Southwest Sumba

Background: Diarrhea is a prevalent health issues in developing countries, and often linked to soil-transmitted helminthiasis (STH). This study aims to investigate the association between STH and diarrhea in Perobatang, Southwest Sumba (SBD). Method: A cross-sectional study was conducted in Perobatang, SBD, in January 2017. Participants were children aged 1 – 15 years. Stool samples were collected from each child and examined macroscopically for signs of diarrhea and microscopically for STH eggs. Positive cases were treated with albendazole. Result: A total of 333 samples were analyzed and 257 children were infected with STH (77%). The prevalence of A. lumbricoides was 56%, T. trichiura was 55%, and hookworm was 5%. Mixed infections were more common in children 6 – 15 years. Ninety-two children (28%) exhibited diarrhea. A significant association was observed between the STH infection (combination of all three worm species) and diarrhea incidence (chi-square test, p &lt; 0.05). However, no correlation was found between the prevalence of single infections or the combination of two worm species and diarrhea incidence. Conclusion: STH infections are associated with incidence of diarrhea in Perobatang, Sumba Barat Daya. This finding highlights the necessity for targeted, community-based interventions by local stakeholders to effectively address and mitigate this public health challenge.

Co-detection of respiratory pathogens among ILI patients: characterization of samples collected during the 2018/19 and 2019/20 pre-pandemic seasons

Influenza-like illness (ILI) patients co-detected with respiratory pathogens exhibit poorer health outcomes than those with single infections. To address the paucity of knowledge concerning the incidence of concurrent respiratory pathogens, their relationships, and the clinical differences between patients detected with single and multiple pathogens, we performed an in-depth characterization of the oropharyngeal samples of primary care patients collected in Genoa (Northwest Italy), during winter seasons 2018/19–2019/20.The apriori algorithm was employed to evaluate the incidence of viral, bacterial, and viral-bacterial pairs during the study period. The grade of correlation between pathogens was investigated using the Phi coefficient. Factors associated with viral, bacterial or viral-bacterial co-detection were assessed using logistic regression.The most frequently identified pathogens included influenza A, rhinovirus, Haemophilus influenzae and Streptococcus pneumoniae. The highest correlations were found between bacterial-bacterial and viral-bacterial pairs, such as Haemophilus influenzae-Streptococcus pneumoniae, adenovirus-Haemophilus influenzae, adenovirus-Streptococcus pneumoniae, RSV-A-Bordetella pertussis, and influenza B Victoria-Bordetella parapertussis. Viruses were detected together at significantly lower rates. Notably, rhinovirus, influenza, and RSV exhibited significant negative correlations with each other. Co-detection was more prevalent in children aged < 4, and cough was shown to be a reliable indicator of viral co-detection.Given the evolving epidemiological landscape following the COVID-19 pandemic, future research utilizing the methodology described here, while considering the circulation of SARS-CoV-2, could further enrich the understanding of concurrent respiratory pathogens.

Detection of Eimeria Species in Naturally Infected Poultry using Multiplex Polymerase Chain Reaction in Chhattisgarh, India

Background: The present study was undertaken to detect the species of Eimeria in naturally infected poultry using multiplex PCR in organized and unorganized farms of four districts namely Bilaspur, Durg, Korba and Rajnandgaon in plain region of Chhattisgarh. Methods: Multiplex PCR was carried out using primer pairs of seven species and it revealed that there were only 1-3 species of Eimeria per farm and a total of 4 species were only detected in all 4 districts and these were E. acervulina, E. tenella, E. maxima and E. brunetti with the presence of 50.0%, 43.75%, 37.5% and 12.5% among infected farms, respectively. Result: These samples showed the highest incidence of E. acervulina and lowest incidence of E. brunetti. As per multiplex PCR, mixed infection was present in 37.5% farms and single infection was present in 56.25% farms.

Pathogenicity of duck circovirus and novel goose parvovirus co-infection in SPF ducks

ABSTRACT Duck circovirus (DuCV) is one of the most prevalent infectious viruses in the duck industry in China. Although the clinical signs vary, it often causes immunosuppression in the host and leads to secondary infection with other pathogens. Novel goose parvovirus (NGPV) mainly infects ducks and causes short beak and dwarfism syndrome in ducks. However, the incidence of infection in ducks has increased in recent years, and the phenomenon of mixed infection with DuCV is common, resulting in more severe clinical morbidity. However, there are no systematic studies evaluating the presence of mixed infections. In order to investigate the synergistic pathogenicity of DuCV and NGPV co-infection in SPF ducks, a comparative experiment using DuCV and NGPV co-infection and mono-infection bird models was established. The results showed that the clinical signs of short beak, dwarfism and immunosuppression were more obvious in DuCV and NGPV co-infected ducks; the tissue damage of target organs was more serious, and the viral titre in organs and cloacal swabs were more significant compared with those of SPF ducks infected with only one virus. The results indicated that co-infection with DuCV and NGPV could promote viral replication and cause more severe tissue damage and immunosuppression than single virus infection. The present study reveals that the co-infection of NGPV and DuCV has a synergistic pathogenic effect from the aspect of pathogenicity, and the conclusions drawn not only clarify the direction of the subsequent research on the mechanism of co-infection of NGPV and DuCV, but also provide a scientific basis for the research on the co-infection of immunosuppressive pathogens and other pathogens.

Circulation of Non-falciparum Species in Niger: Implications for Malaria Diagnosis.

Niger's National Malaria Control Programme and its partners use histidine-rich protein 2-based RDTs, which are specific to Plasmodium falciparum diagnosis. This study aimed to screen for the circulation of non-falciparum species in Zinder, a region of Niger, West Africa. A cross-sectional study was carried out from July to December 2022 at the district hospital of the Zinder region of Niger. P falciparum histidine-rich protein 2-based rapid diagnostic tests were performed, and dried blood spot samples were collected for further laboratory multiplexed photo-induced electron transfer-polymerase chain reaction (PET-PCR) analysis on positive light microscopy from all patients with fever who attended the Zinder district hospital during the study period. In total, 340 dried blood spots were collected and analyzed by PET-PCR. Overall, 73.2% (95% CI, 68.2%-77.9%; 249/340) were positive for Plasmodium genus and species and represented the study population. Plasmodium species proportions were 89.5% (95% CI, 85.1%-93.1%; 223/249) for P falciparum, 38.5% (95% CI, 32.5%-44.9%; 96/249) for P malariae, 10.8% (95% CI, 7.3%-15.4%; 27/249) for P vivax, and 1.6% (95% CI, .4%-4.1%; 4/249) for P ovale. Single infection with Plasmodium species counted for 61.8% (95% CI, 55.5%-67.9%; 154/249), and the mixed infections rate, with at least 2 Plasmodium species, was 38.1% (95% CI, 32.1%-44.5%; 95/249). Single non-falciparum infections represented a rate of 10.0% (95% CI, 6.6%-14.5%; 25/249). This study confirms the first evidence of Plasmodium vivax by PET-PCR in Niger in addition to the other 3 Plasmodium species. These findings underline the need to adapt malaria diagnostic tools and therapeutic management, as well as the training of microscopists, for recognition of non-falciparum plasmodial species circulating in the country. This will better inform the strategies toward malaria control and elimination, as well as the decision making of the health authorities of Niger.

The public health and economic burden of long COVID in Australia, 2022-24: a modelling study.

To estimate the number of people in Australia with long COVID by age group, and the associated medium term productivity and economic losses. Modelling study: a susceptible-exposed-infected-recovered (SEIR) model to estimate the number of people with long COVID over time following single infections, and a labour supply model to estimate productivity losses as a proportion of gross domestic product (GDP). Australia, 2022-2024. Estimated number of people infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during 2022-2023 (based on serosurvey data) who have longCOVID, 2022-2024, by age group; estimated GDP loss during 2022 caused by reduced labour supply attributable to long COVID. Our model projected that the number of people with long COVID following a single infection in 2022 would peak in September 2022, when 310 341-1 374 805 people (1.2-5.4% of Australians) would have symptoms of long COVID, declining to 172 530-872 799 people (0.7-3.4%) in December 2024, including 7902-30 002 children aged 0-4 years (0.6-2.2%). The estimated mean labour loss attributable to long COVID in 2022 was projected to be 102.4million (95% confidence interval [CI], 50.4-162.2 million) worked hours, equivalent to 0.48% (95% CI, 0.24-0.76%) of total worked hours in Australia during the 2020-21 financial year. The estimated mean GDP loss caused by the projected decline in labour supply and reduced use of other production factors was $9.6 billion (95% CI, $4.7-15.2 billion), or 0.5% of GDP. The estimated labour loss was greatest for people aged 30-39 years (27.5 million [95% CI, 16.0-41.0 million] hours; 26.9% of total labour loss) and people aged 40-49 years (24.5 million [95% CI, 12.1-38.7 million] hours; 23.9% of total labour loss). Widespread SARS-CoV-2 infections in Australia mean that even a small proportion of infected people developing long COVID-related illness and disability could have important population health and economic effects. A paradigm shift is needed, from a sole focus on the immediate effects of coronavirus disease 2019 (COVID-19) to preventing and treating COVID-19 and treating long COVID, with implications for vaccine and antiviral policy and other mitigation of COVID-19.

Patterns of single and multiple HPV infections in female: A systematic review and meta-analysis

BackgroundData on the patterns of single and multiple HPV infections are largely limited to small size studies, and the regional difference have not been systematically examined. MethodsA literature search was conducted using PubMed, Embase, and Web of Science databases up to Sept 22, 2023. The pooled prevalence of HPV infection were calculated using random-effects meta-analysis. Subgroup analysis was used to explore the heterogeneity, and publication bias was evaluated by Egger's test and Begg's test. ResultsThere were 121 studies included with 1,682,422 participants. Globally, the most common genotypes of single HPV infection were HPV16 (7.05 %), 18 (1.94 %), 52 (1.93 %), 58 (1.68 %), and 31 (1.53 %), as well as HPV 16 (4.91 %), 31 (2.68 %), 52 (2.20 %), 51 (1.99 %), and 18 (1.96 %) in multiple HPV infections. Apart from HPV16 and 18, HPV52 and 58 were common in Asia, HPV31 and 51 was in Europe, North and South America, and HPV35 and 45 were in Africa. The prevalence of HPV infection among different age groups (<30, 30–50, >50 years age groups) was 20.93 %, 16.27 %, and 18.69 %, respectively. The single HPV infection prevalence in the No-ILs, LSILs, HSILs, and cervical cancer groups were 16.17 %, 51.60 %, 57.12 %, and 62.88 %, respectively, as well as in multiple infections were 5.09 %, 30.93 %, 32.86 %, and 21.26 % ConclusionDeveloping local HPV vaccines is necessary based on the HPV infection pattern. It is essential to educate young women to get vaccinated and encourage elderly women to have regular cervical cancer screenings to reduce the danger of cervical cancer.

Feline vector-borne haemopathogens in Türkiye: the first molecular detection of Mycoplasma wenyonii and ongoing Babesia ovis DNA presence in unspecific hosts

BackgroundCats are hosts and reservoirs for many haemopathogens such as piroplasms, Rickettsia, hemotropic Mycoplasma, Bartonella, Ehrlichia, and Anaplasma, which are transmitted by various vector arthropods and some of which have a zoonotic concern. Although it is noteworthy that the rate of ownership of companion animals has increased in Türkiye in recent years and that cats account for a large proportion of these animals, there is limited research on the vector-borne infectious agents carried by them. The present study aimed to provide a comprehensive molecular epidemiological data and molecular characterization of feline vector-borne haemopathogens (FVBHs), including piroplasms, anaplasmataceae, rickettsias, haemoplasmas, and Bartonella species in Türkiye. In total, 250 feline blood samples were collected from client-owned cats (n = 203) and shelter cats (n = 47) brought to the Small Animal Hospital of Selcuk University, Veterinary Faculty.ResultsOverall, 40 (16%) cats were found to be infected with at least one of the investigated haemopathogens and piroplasm, Mycoplasma spp. and Bartonella spp. prevalence was 1.6%, 11.2%, and 4.8%, respectively. No Anaplasma/Ehrlichia spp. and Rickettsia spp. DNA was detected in the investigated feline samples. Sequence analysis revealed that all four piroplasms belonged to Babesia ovis with a 97.93–99.82% nucleotide sequence identity to 18S rRNA gene sequences from Spain and Türkiye, while some sequenced hemoplasmas were Mycoplasma haemofelis (Mhf), Candidatus Mycoplasma haemominutum (CMhm) and Mycoplasma wenyonii, and Bartonella spp. were Bartonella henselae and Bartonella koehlerae species. Co-infections with Mycoplasma spp. and Bartonella spp. were also detected in 4 cats (1.6%) in this study, where single infections were predominant.ConclusionThis study provides valuable information on zoonotically important feline vector-borne hemopathogens in Türkiye, some of which have received attention under the One Health perspective, and is the first molecular epidemiological study to demonstrate the presence of Babesia ovis, the causative agent of ovine babesiosis, and Mycoplasma wenyonii DNA, the causative agent of bovine haemotropic mycoplasmosis, in cats. Further studies on the roles of such pathogens detected in unspecific hosts and the host specificity of the vectors that transmit them will contribute to the elucidation of this situation.

Comparative Cross-Kingdom DDA- and DIA-PASEF Proteomic Profiling Reveals Novel Determinants of Fungal Virulence and a Putative Druggable Target.

Accurate and reliable detection of fungal pathogens presents an important hurdle to manage infections, especially considering that fungal pathogens, including the globally important human pathogen, Cryptococcus neoformans, have adapted diverse mechanisms to survive the hostile host environment and moderate virulence determinant production during coinfections. These pathogen adaptations present an opportunity for improvements (e.g., technological and computational) to better understand the interplay between a host and a pathogen during disease to uncover new strategies to overcome infection. In this study, we performed comparative proteomic profiling of an in vitro coinfection model across a range of fungal and bacterial burden loads in macrophages. Comparing data-dependent acquisition and data-independent acquisition enabled with parallel accumulation serial fragmentation technology, we quantified changes in dual-perspective proteome remodeling. We report enhanced and novel detection of pathogen proteins with data-independent acquisition-parallel accumulation serial fragmentation (DIA-PASEF), especially for fungal proteins during single and dual infection of macrophages. Further characterization of a fungal protein detected only with DIA-PASEF uncovered a novel determinant of fungal virulence, including altered capsule and melanin production, thermotolerance, and macrophage infectivity, supporting proteomics advances for the discovery of a novel putative druggable target to suppress C. neoformans pathogenicity.

Development of a TaqMan-based multiplex real-time PCR for simultaneous detection of porcine epidemic diarrhea virus, Brachyspira hyodysenteriae, and Lawsonia intracellularis.

PEDV, Brachyspira hyodysenteriae, and Lawsonia intracellularis, are highly contagious diarrheal pathogens that have caused significant harm to the global swine industry. Co-infections with multiple pathogens are common, making it challenging to identify the actual causative agents depending only on clinical information. It is crucial to develop a reliable method to simultaneously detect and differentiate these pathogens. Based on the conserved regions of the M gene of PEDV, NADH oxidase gene of B. hyodysenteriae, and the 16S rDNA gene of L. intracellularis, specific probes and primers for the multiplex real-time PCR assay were designed. The concentrations of primers and probes were optimized using a matrix method. The approach demonstrated high specificity and no cross-reactivity with major pathogens related to diarrheal diseases. It showed high sensitivity with a detection limit of 10 copies/μL for B. hyodysenteriae and L. intracellularis, and 100 copies/μL for PEDV, respectively. It also demonstrated high reproducibility and stability with low coefficients of variation. Results from the multiplex real-time PCR method were in complete agreement with the commercial singleplex real-time PCR kit for detecting PEDV, B. hyodysenteriae and L. intracellularis. Clinical data revealed single infection rates of 31.46% for PEDV, 58.43% for B. hyodysenteriae, and 98.6% for L. intracellularis. The co-infection rates were 16.85% for PEDV + B. hyodysenteriae, 31.46% for PEDV + L. intracellularis, 57.86% for B. hyodysenteriae + L. intracellularis, and 16.85% for PEDV + B. hyodysenteriae + L. intracellularis, respectively. The new multiplex real-time PCR method can simultaneously differentiate PEDV, B. hyodysenteriae and L. intracellularis, making it a valuable diagnostic tool for preventing and controlling infectious diseases, as well as aiding in epidemiological investigations.

Co-infection dynamics of B. afzelii and TBEV in C3H mice: insights and implications for future research.

Ticks are important vectors of disease, particularly in the context of One Health, where tick-borne diseases (TBDs) are increasingly prevalent worldwide. TBDs often involve co-infections, where multiple pathogens co-exist in a single host. Patients with chronic Lyme disease often have co-infections with other bacteria or parasites. This study aimed to create a co-infection model with Borrelia afzelii and tick-borne encephalitis virus (TBEV) in C3H mice and to evaluate symptoms, mortality, and pathogen level compared to single infections. Successful co-infection of C3H mice with B. afzelii and TBEV was achieved. Outcomes varied, depending on the timing of infection. When TBEV infection followed B. afzelii infection by 9 days, TBEV symptoms worsened and virus levels increased. Conversely, mice infected 21 days apart with TBEV showed milder symptoms and lower mortality. Simultaneous infection resulted in mild symptoms and no deaths. However, our model did not effectively infect ticks with TBEV, possibly due to suboptimal dosing, highlighting the challenges of replicating natural conditions. Understanding the consequences of co-infection is crucial, given the increasing prevalence of TBD. Co-infected individuals may experience exacerbated symptoms, highlighting the need for a comprehensive understanding through refined animal models. This study advances knowledge of TBD and highlights the importance of exploring co-infection dynamics in host-pathogen interactions.

HPV specificity and multiple infections and association with cervical cytology in Chongqing, China: a cross-sectional study

BackgroundIt is important to assess the relationship between specific HPV genotype or multiple infection and cervical cytology. The protection provided by the HPV vaccine is type-specific, and the epidemiology feature of coinfections needs to be investigated. The aim is to provide baseline information for developing HPV vaccination and management of HPV-positive populations in the region.MethodsA total of 3649 HPV-positive women were collected from 25,572 women who underwent 15 HR-HPV genotypes and ThinPrep cytologic test (TCT) results. Logistic regression was used to determine the correlation between the risk of cytology abnormalities and specific HPV infection. We calculated odds ratios (ORs) to assess coinfection patterns for the common two-type HPV infections. chi-squared test was used to estimate the relationship between single or multiple HPV (divided into species groups) infection and cytology results.ResultsThe results showed there was a positive correlation between HPV16 (OR = 4.742; 95% CI 3.063–7.342) and HPV33 (OR = 4.361; 95% CI 2.307–8.243) infection and HSIL positive. There was a positive correlation between HPV66 (OR = 2.445; 95% CI 1.579–3.787), HPV51 (OR = 1.651; 95% CI 1.086–2.510) and HPV58(OR = 1.661; 95% CI 1.166–2.366) infection and LSIL. Multiple HPV infections with α9 species (OR = 1.995; 95% CI 1.101–3.616) were associated with a higher risk of high-grade intraepithelial lesions (HSIL) compared with single HPV infection. There were positive correlations between HPV66 and HPV56 (α6) (OR = 3.321; 95% CI 2.329–4.735) and HPV39 and HPV68 (α7). (OR = 1.677; 95% CI 1.127–2.495). There were negative correlations between HPV52, 58, 16 and the other HPV gene subtypes.ConclusionHPV33 may be equally managed with HPV16. The management of multiple infections with α9 may be strengthened. The 9-valent vaccine may provide better protection for the population in Chongqing currently. The development of future vaccines against HPV51 and HPV66 may be considered in this region.

Influence of biosecurity on the occurrence of various enteric viruses in broiler flocks

ABSTRACT Common enteric viruses affecting commercial broiler flocks include fowl adenovirus (FAdV), chicken parvovirus (ChPV), chicken astrovirus (CAstV), avian reovirus (ARV) and avian rotavirus (AvRV). To investigate their prevalence and to identify single and multiple infections we collected intestinal samples from 49 Austrian broiler flocks during necropsy of dead-on-farm birds twice during a production cycle (7–14 days and 28–35 days). Altogether, up to three consecutive clinically healthy flocks without signs of gastrointestinal disease were sampled from 17 different farms. Samples were analysed using virus isolation and PCR/RT–PCR methods. Virus prevalence was correlated with production data and on-farm biosecurity and management practices. Overall, ARV (75%) was most commonly detected in the flocks, followed by CAstV (61%), ChPV (61%), FAdV (57%) and AvRV (8%). Only in three (6%) flocks were none of the investigated enteric viruses detected. Flock infection profiles were very heterogeneous and included individual detection of the investigated viruses as well as different combinations thereof (up to all five investigated viruses). Even in the absence of clinical diarrhoea and/or macroscopic intestinal lesions, statistical analysis confirmed that the number of viruses detected had a significant economic impact characterised by poor weight gain and increased mortality, particularly due to the presence of FAdV, CAstV and/or ARV. Furthermore, the use of barn-specific clothing and/or footbaths as well as regular vermin control, resulted in lower prevalence of enteric viruses in the flocks studied. This highlights the importance of common biosecurity measures in poultry production to prevent economic losses. RESEARCH HIGHLIGHTS Detection timepoints and patterns indicate horizontal introduction of various enteric viruses. Flock infection profiles were very heterogeneous; no dominating virus profile. Broiler production was negatively affected by the number of enteric viruses detected. Common biosecurity measures had a significant negative effect on virus prevalence.

A new protocol for multispecies bacterial infections in zebrafish and their monitoring through automated image analysis.

The zebrafish Danio rerio has become a popular model host to explore disease pathology caused by infectious agents. A main advantage is its transparency at an early age, which enables live imaging of infection dynamics. While multispecies infections are common in patients, the zebrafish model is rarely used to study them, although the model would be ideal for investigating pathogen-pathogen and pathogen-host interactions. This may be due to the absence of an established multispecies infection protocol for a defined organ and the lack of suitable image analysis pipelines for automated image processing. To address these issues, we developed a protocol for establishing and tracking single and multispecies bacterial infections in the inner ear structure (otic vesicle) of the zebrafish by imaging. Subsequently, we generated an image analysis pipeline that involved deep learning for the automated segmentation of the otic vesicle, and scripts for quantifying pathogen frequencies through fluorescence intensity measures. We used Pseudomonas aeruginosa, Acinetobacter baumannii, and Klebsiella pneumoniae, three of the difficult-to-treat ESKAPE pathogens, to show that our infection protocol and image analysis pipeline work both for single pathogens and pairwise pathogen combinations. Thus, our protocols provide a comprehensive toolbox for studying single and multispecies infections in real-time in zebrafish.