Distribution and diagnostic value of single and multiple high-risk HPV infections in detection of cervical intraepithelial neoplasia: A retrospective multicenter study in China.

The risk associated with single and multiple human papillomavirus (HPV) infections in cervical intraepithelial neoplasia (CIN) remains uncertain. This study aims to explore the distribution and diagnostic significance of the number of high-risk HPV (hr-HPV) infections in detecting CIN, addressing a crucial gap in our understanding. This comprehensive multicenter, retrospective study meticulously analyzed the distribution of single and multiple hr-HPV, the risk of CIN2+, the relationship with CIN, and the impact on the diagnostic performance of colposcopy using demographic information, clinical histories, and tissue samples. The composition of a single infection was predominantly HPV16, 52, 58, 18, and 51, while HPV16 and 33 were identified as the primary causes of CIN2+. The primary instances of dual infection were mainly observed in combinations such as HPV16/18, HPV16/52, and HPV16/58, while HPV16/33 was identified as the primary cause of CIN2+. The incidence of hr-HPV infections shows a dose-response relationship with the risk of CIN (p for trend <0.001). Compared to single hr-HPV, multiple hr-HPV infections were associated with increased risks of CIN1 (1.44, 95% confidence interval [CI]: 1.20-1.72), CIN2 (1.70, 95% CI: 1.38-2.09), and CIN3 (1.08, 95% CI: 0.86-1.37). The colposcopy-based specificity of single hr-HPV (93.4, 95% CI: 92.4-94.4) and multiple hr-HPV (92.9, 95% CI: 90.8-94.6) was significantly lower than negative (97.9, 95% CI: 97.0-98.5) in detecting high-grade squamous intraepithelial lesion or worse (HSIL+). However, the sensitivity of single hr-HPV (73.5, 95% CI: 70.8-76.0) and multiple hr-HPV (71.8, 95% CI: 67.0-76.2) was higher than negative (62.0, 95% CI: 51.0-71.9) in detecting HSIL+. We found that multiple hr-HPV infections increase the risk of developing CIN lesions compared to a single infection. Colposcopy for HSIL+ detection showed high sensitivity and low specificity for hr-HPV infection. Apart from HPV16, this study also found that HPV33 is a major pathogenic genotype.

A simplified laboratory approach for isolating M. oryzae spores from rice samples infected with multiple pathogens.

A method for separating M. oryzae from rice samples infected with multiple pathogens using basic laboratory equipment is described. We conducted a series of experiments to obtain a single spore of M. oryzae. This method can also be used to isolate spores from other fungal species.

Pattern of multiple human papillomavirus infection and type competition: An analysis in healthy Chinese women aged 18-45 years.

To assess the pattern of multiple human papillomavirus infection to predict the type replacement postvaccination. A total of 7372 women aged 18-45y from a phase III trial of an Escherichia coli-produced HPV-16/18 vaccine were analyzed at enrollment visit before vaccination. Hierarchical multilevel logistic regression was used to evaluate HPV vaccine type and nonvaccine-type interactions with age as a covariate. Binary logistic regression was construed to compare multiple infections with single infections to explore the impact of multiple-type infections on the risk of cervical disease. Multiple HPV infections were observed in 25.2% of HPV-positive women and multiple infections were higher than expected by chance. Statistically significant negative associations were observed between HPV16 and 52, HPV18 and HPV51/52/58, HPV31 and HPV39/51/52/53/54/58, HPV33 and HPV52/58, HPV58 and HPV52, HPV6 and HPV 39/51/52/53/54/56/58. Multiple HPV infections increased the risk of CIN2+ and HSIL+, with the ORs of 2.27(95%CI: 1.41, 3.64) and 2.26 (95%CI: 1.29, 3.95) for multiple oncogenic HPV infection separately. However, no significant evidence for the type-type interactions on risk of CIN2+ or HSIL+. There is possibility of type replacement between several pairs of vaccine and nonvaccine HPV type. Multiple HPV infection increased the risk of cervical disease, but coinfection HPV types seem to follow independent disease processes. Continued post-vaccination surveillance for HPV 51/52/58 types and HPV 39/51 types separately was essential after the first and second generation of HPV vaccination implementation in China.

Three different routes of EHEC O157:H7 infection were used to establish EHEC broiler model.

In order to study the prevention and control EHEC disease measures in poultry, the infection process and development of this disease and the pathological changes of various organs were to be observed. In this study, chickens were infected with different doses of enterohemorrhagic Escherichia coli (EHEC) O157:H7 using different routes of administration to establish EHEC broiler model. A total of 195 14-day-old broilers were randomly divided into 13 groups: including control group, Enema-drip groups (1010, 1011, 1012, 1013 CFUs E. coli O157:H7), gavage groups (P.O) (1011, 1012, 1013, 1014 CFUs E. coli O157:H7), and intraperitoneal injection group (I.P.) (108, 109, 1010, 1011 CFUs E. coli O157:H7). Escherichia coli (E. coli) was given using enema-drip, gavage or intraperitoneal infection. Then the feed intake, weight changes, stool and clinical symptoms of the chicks were recorded during the experiment. 7 d after E. coli infection, blood was collected from the jugular vein and serological tests were carried out. The liver, spleen, and colon of the chicks were extracted to get the organ index, bacteria load, and their histopathological changes. After infection with E. coli, some chicks feces were green or red watery stool, sometimes accompanied by foam, and the material to weight ratio of broilers in I.P. group increased significantly (P < 0.05), the 108 CFUs group were 1.3 times as large as control group. Three modeling methods can result in abnormal serum lipid metabolism and liver function indexes (increase of AST, TBA, T-Bil and TC level; decrease of ALB, TG, and TP level). Infection of chicks with O157:H7 by all 3 methods resulted in its detection in the liver, spleen, and colon. Three modeling methods significantly decreased liver index, and inflammatory cell infiltration and hyperemia were observed in liver. The spleen index in E. coli broilers by gavage and enema-drip was significantly decreased, splenic hyperemia and periarteriolar hyalinosis were observed. The spleen was enlarged with purplish-black spheroids in I.P. group broilers, and the spleen histological changes was more serious. The colon villi of broilers in gavage and enema-drip groups were thinner, more prone to rupture, intestinal lamina propria hyperemia, and inflammatory cell infiltration. Moreover, the number of goblet cells in the mucosal epithelium increased. E. coli O157:H7 can induce liver, spleen and intestinal damage and reduce growth performance of chicks. By comparing these 3 methods, we found that chicks infected with O157:H7 by gavage had more severe liver and intestinal damage, the enema-drip method caused most serious intestinal damage, and I.P. method significantly damaged the liver and spleen of chickens.

Increased virulence due to multiple infection in Daphnia leads to limited growth in 1 of 2 co-infecting microsporidian parasites.

Recent outbreaks of various infectious diseases have highlighted the ever-present need to understand the drivers of the outbreak and spread of disease. Although much of the research investigating diseases focuses on single infections, natural systems are dominated by multiple infections. These infections may occur simultaneously, but are often acquired sequentially, which may alter the outcome of infection. Using waterfleas (Daphnia magna) as a model organism, we examined the outcome of sequential and simultaneous multiple infections with 2 microsporidian parasites (Ordospora colligata and Hamiltosporidium tvaerminnensis) in a fully factorial design with 9 treatments and 30 replicates. We found no differences between simultaneous and sequential infections. However, H. tvaerminnensis fitness was impeded by multiple infection due to increased host mortality, which gave H. tvaerminnensis less time to grow. Host fecundity was also reduced across all treatments, but animals infected with O. colligata at a younger age produced the fewest offspring. As H. tvaerminnensis is both horizontally and vertically transmitted, this reduction in offspring may have further reduced H. tvaerminnensis fitness in co-infected treatments. Our findings suggest that in natural populations where both species co-occur, H. tvaerminnensis may evolve to higher levels of virulence following frequent co-infection by O. colligata.

Genetic variability analysis of human papillomavirus 58: Novel sublineage identification and persistent infection association.

This study aims to characterize the genetic variability of HPV58, identify novel lineages and sublineages, and explore the association between persistent/multiple HPV58 infections and genetic variation. In this study, samples from 124 women with HPV58 infection in Eastern China were collected and 81 isolates of E6 and L1 full-length genes were successfully amplified from 55 samples. We evaluated the diversity of genetic variants and performed correlation analyses between genetic variability and pathology, vaccination, multiple infections, and persistent infections. Among the E6 and L1 gene sequences collected, the dominant prevailing sublineages were A1 (46.2%) and A2 (23.1%). In addition, we found two potential novel sublineages denoted as the A4 and A5 sublineage. A total of 50 nucleotide substitutions, including 28 synonymous substitutions and 22 nonsynonymous substitutions, were observed in the E6 and L1 genes. Among them, variants with A388C/K93N substitutions in the E6 gene correlated with persistent infection (≥1 and ≥2 years) (p < 0.005), and C307T/C66C was associated with persistent infection (≥2 years) (p < 0.005). Notably, two mutations above were detected in the isolate from the patient with breakthrough vaccine infection. Our study found two novel sublineages and sites of genetic variability in multiple and persistent infection variants. In addition, we identified two mutational sites associated with persistent infection. This study provides new insight into the clinical characteristics of HPV 58 genetic variations and offers new ideas for research on next-generation vaccines in Eastern China.

Misdiagnosed periappendiceal and intestinal tuberculosis during the COVID-19 pandemic.

Introduction and importance: The coronavirus disease 2019 (COVID-19) was first reported in Wuhan, Hubei Province, China. It mainly involves the respiratory system, causing fever, cough, chest tightness, and other symptoms. However, when combined with other common or rare diseases, such as appendicitis and intestinal tuberculosis (TB), it can cause other systemic lesions, thus making the original disease lose its specific clinical manifestations. This case highlights the importance of early identification and clinical precision medicine diagnosis and treatment. Case presentation: A young woman presented with intermittent pain and discomfort in the right lower quadrant. Ultrasonography suggested appendicitis with a peripheral abscess. The nucleic acid test of COVID-19 was positive, and the chest computed tomography scan showed pulmonary involvement. She was sent for surgery. Postoperative body temperature increased regularly, and the TB T-cell test was positive. Clinical discussion: Multiple infections caused by common bacteria, pandemic virus, and specific mycobacterium TB cause a series of nonspecific clinical manifestations, which brings challenges to clinical diagnosis and treatment. Therefore, when facing a complex infection case, the authors should consider the possibility of multiple infections and give targeted treatment for the pathogens. Conclusions: During the epidemic of COVID-19, the incidence of intestinal TB is relatively low, which is easy to be overlooked and misdiagnosed, especially in the case of appendicitis. Therefore, clinicians must be highly vigilant in the diagnosis process to avoid missed diagnosis or misdiagnosis, so as to provide the best diagnosis and treatment plan.

Identification of Potential Hazards Associated with South Korean Prawns and Monitoring Results Targeting Fishing Bait.

This study detected two potential pathogens, Vibro parahaemolyticus, which causes acute hepatopancreatic necrosis disease (AHPND), and white spot syndrome virus (WSSV), in fishing bait in South Korea. However, their infectious nature was not confirmed, possibly due to the degradation caused by freezing/thawing or prolonged storage under frozen conditions. While infectivity was not confirmed in this study, there is still a significant risk of exposure to these aquatic products. Furthermore, fishing bait and feed should be handled with caution as they are directly exposed to water, increasing the risk of disease transmission. In Australia, cases of WSSV infection caused by imported shrimp intended for human consumption have occurred, highlighting the need for preventive measures. While freezing/thawing is a method for inactivating pathogens, there are still regulatory and realistic issues to be addressed.

Mixed (multiple-genotype) Helicobacter pylori infections in Bulgarian patients.

The aim of the study was to evaluate the frequency and characteristics of mixed (multiple-genotype) Helicobacter pylori infections (MGIs) in 155 Bulgarian symptomatic patients (21 children and 134 adults). MGIs were common (36.1%), including double-strain (34.8%) and triple-strain infections (1.3%). None of the 8 ulcer patients harbored multiple subtypes. We detected 18 multiple allelic combinations, of which the most frequent subtypes (17.4%) were vacA s1as2 and vacA s1cs2. The 2 patients with triple-strain infections had vacA s1bs1cs2i1i2/iceA1A2 and vacA s1as1cs2 subtypes. They were both adult men with chronic gastritis and both were examined in 2022. The prevalence of MGIs (51.7%) was 2-fold higher in 2020 to 2022 than in 2015 to 2019 (26.3%). Putative factors for the increase may be the patient's characteristics and COVID-19 pandemic-associated factors. MGI rates corresponded to the high infection seroprevalence (72.4% in 2011) in Bulgaria. The evolution and clinical importance of mixed H. pylori infections merit extensive evaluation.

Multiple infections containing the top five prevalent HPV genotypes and their impact on cervical lesions in Changzhou, China.

Human papillomavirus (HPV) infection is the primary cause of cervical cancer and its precursor lesions. The overall prevalence of HPV genotypes in Changzhou has previously been reported. However, the distribution of multiple HPV infections and their roles in cervical injury have less been investigated. We aimed to assess the prevalence of multiple HPV infections among the people in Changzhou. Furthermore, we analyzed whether multiple HPV infections comprising the top five prevalent HPVs were more associated with abnormalities in E6 and E7 (E6/E7) mRNA, liquid-based cytology, and cervical histopathology than a single infection. In the current study, HPV 16, 52, 58, 53, and 81 were the top five prevalent HPV types, both in single and multiple infections. Compared to a single infection, multiple infections containing HPV 16/52/58 were closely linked to positivity for E6/E7 mRNA. In addition to HPV 16, multiple infections containing the remaining top four HPVs conferred a significant advantage on atypical squamous cells of undermined significance or worse in comparison to a single infection. Furthermore, women with multiple infections containing the top five prevalent HPV types were more likely to develop cervical intraepithelial neoplasia grade II or worse than those with a single HPV infection. Our results demonstrate the superiority of multiple HPV infections containing the top five prevalent HPV types in cervical disease progression, which should be closely monitored. These findings are conducive for formulating regional preventive strategies for cervical cancer screening and vaccination in Changzhou.

The role of cell-to-cell transmission in HIV infection: insights from a mathematical modeling approach.

HIV infection remains a serious global public health problem. Although current drug treatment is effective and can reduce plasma viral loads below the level of detection, it cannot eradicate the virus. The reasons for the low virus persistence despite long-term therapy have not been fully elucidated. In addition, multiple HIV infection, i.e., infection of a cell by multiple viruses, is common and can facilitate viral recombination and mutations, evading the immune system and conferring resistance to drug treatment. The mechanisms for multiple HIV infection formation and their respective contributions remain unclear. To answer these questions, we developed a mathematical modeling framework that encompasses cell-free viral infection and cell-to-cell spread. We fit sub-models that only have one transmission route and the full model containing both to the multi-infection data from HIV-infected patients, and show that the multi-infection data can only be reproduced if these two transmission routes are both considered. Computer simulations with the best-fitting parameter values indicate that cell-to-cell spread leads to the majority of multiple infection and also accounts for the majority of overall infection. Sensitivity analysis shows that cell-to-cell spread has reduced susceptibility to treatment and may explain low HIV persistence. Taken together, this work indicates that cell-to-cell spread plays a crucial role in the development of HIV multi-infection and low HIV persistence despite long-term therapy, and therefore has important implications for understanding HIV pathogenesis and developing more effective treatment strategies to control or even eliminate the disease.

Pattern of infection and genotypes of human papillomavirus in Zhengzhou City based on a four-year (2015-2018) epidemiological study.

Persistent human papillomavirus (HPV) infection has been associated with the development of cervical cancer. To reduce the incidence of cervical cancer and promote awareness of HPV, a government-sponsored epidemiological study was conducted from 2015 to 2018 in Zhengzhou City. A total of 184,092 women aged 25-64 years were included, of which 19,579 were infected with HPV, reflecting a prevalence of 10.64 percent (19,579/184,092). The HPV genotypes found were classified as high-risk (13 genotypes) and low-risk (8 genotypes). Single and multiple infections were detected in 13,787 (70.42 percent) and 5,792 (29.58 percent) women, respectively. The five most common high-risk genotypes detected, listed in descending order, were HPV52 (2.14 percent; 3,931/184,092), HPV16 (2.04 percent; 3,756/184,092), HPV58 (1.42 percent; 2,607/184,092), HPV56 (1.01 percent; 1,858/184,092), and HPV39 (0.81 percent; 1,491/184,092). Meanwhile, the most common low-risk genotype was HPV53 (0.88 percent; 1,625/184,092). The prevalence of HPV gradually increased with age, with the highest occurring in women aged 55-64 years. The prevalence of single-type HPV infection decreased with age, whereas that of multiple-type HPV infection increased with age. This study indicates a high burden of HPV infection in women in Zhengzhou City.

The possible impact of novel mutations in human papillomavirus 52 on the infection characteristics.

Human papillomavirus 52 (HPV52) infection is prevalent in the Chinese population, and variations in HPV52 show correlations with oncogenicity. However, no specific variation in HPV52 was reported to show relevancy to infection characteristics. In this study, we retrieved 222 isolates of E6 and L1 full-length genes from 197 Chinese women with HPV52 infection. After sequence alignment and phylogenetic tree construction, we found that 98.39 % of the collected variants belonged to the sublineage B2 and two variants displayed incongruence between the phylogenetic tree of E6 and L1. The analysis of the infection pattern showed that the presence of C6480A/T mutation in the L1 gene was associated with single infection (P=0.01) and persistent infection (P=0.047) of HPV52, while the A6516G nucleotide change was relevant to transient infection (P=0.018). Our data also indicated that variations T309C in the E6 gene and C6480T, C6600A in L1 were more commonly presented in patients with high-grade cytology (P<0.05). One HPV52 breakthrough infection after vaccination was identified, which hinted at the immune escape post-vaccination. Young coitarche age and non-condom usage were correlated to multiple infections. This study provided insight into the polymorphism of HPV52 and revealed the impact of variations in HPV52 on its infection characteristics.

Ecological Factors Associated with the Distribution of Bemisia tabaci Cryptic Species and Their Facultative Endosymbionts.

The sweetpotato whitefly, Bemisia tabaci species complex, comprises at least 44 morphologically indistinguishable cryptic species, whose endosymbiont infection patterns often varied at the spatial and temporal dimension. However, the effects of ecological factors (e.g., climatic or geographical factors) on the distribution of whitefly and the infection frequencies of their endosymbionts have not been fully elucidated. We, here, analyzed the associations between ecological factors and the distribution of whitefly and their three facultative endosymbionts (Candidatus Cardinium hertigii, Candidatus Hamiltonella defensa, and Rickettsia sp.) by screening 665 individuals collected from 29 geographical localities across China. The study identified eight B. tabaci species via mitochondrial cytochrome oxidase I (mtCOI) gene sequence alignment: two invasive species, MED (66.9%) and MEAM1 (12.2%), and six native cryptic species (20.9%), which differed in distribution patterns, ecological niches, and high suitability areas. The infection frequencies of the three endosymbionts in different cryptic species were distinct and multiple infections were relatively common in B. tabaci MED populations. Furthermore, the annual mean temperature positively affected Cardinium sp. and Rickettsia sp. infection frequencies in B. tabaci MED but negatively affected the quantitative distribution of B. tabaci MED, which indicates that Cardinium sp. and Rickettsia sp. maybe play a crucial role in the thermotolerance of B. tabaci MED, although the host whitefly per se exhibits no resistance to high temperature. Our findings revealed the complex effects of ecological factors on the expansion of the invasive whitefly.

Co-infection of two eukaryotic pathogens within clam populations in Arcachon Bay.

The parasitic species Perkinsus olseni (= atlanticus) (Perkinsea, Alveolata) infects a wide range of mollusc species and is responsible for mortality events and economic losses in the aquaculture industry and fisheries worldwide. Thus far, most studies conducted in this field have approached the problem from a "one parasite-one disease" perspective, notably with regards to commercially relevant clam species, while the impact of other Perkinsus species should also be considered as it could play a key role in the disease phenotype and dynamics. Co-infection of P. olseni and P. chesapeaki has already been sporadically described in Manila clam populations in Europe. Here, we describe for the first time the parasitic distribution of two Perkinsus species, P. olseni and P. chesapeaki, in individual clam organs and in five different locations across Arcachon Bay (France), using simultaneous in situ detection by quantitative PCR (qPCR) duplex methodology. We show that P. olseni single-infection largely dominated prevalence (46-84%) with high intensities of infection (7.2 to 8.5 log-nb of copies. g-1of wet tissue of Manila clam) depending on location, suggesting that infection is driven by the abiotic characteristics of stations and physiological states of the host. Conversely, single P. chesapeaki infections were observed in only two sampling stations, Ile aux Oiseaux and Gujan, with low prevalences 2 and 14%, respectively. Interestingly, the co-infection by both Perkinsus spp., ranging in prevalence from 12 to 34%, was distributed across four stations of Arcachon Bay, and was detected in one or two organs maximum. Within these co-infected organs, P. olseni largely dominated the global parasitic load. Hence, the co-infection dynamics between P. olseni and P. chesapeaki may rely on a facilitating role of P. olseni in developing a primary infection which in turn may help P. chesapeaki infect R. philippinarum as a reservoir for a preferred host. This ecological study demonstrates that the detection and quantification of both parasitic species, P. olseni and P. chesapeaki, is essential and timely in resolving cryptic infections and their consequences on individual hosts and clam populations.

Multiple Infection and Human Immunodeficiency Virus Superinfection Among Persons who Inject Drugs in Indonesia and Ukraine.

BACKGROUND: The HIV Prevention Trials Network (HPTN) 074 study evaluated an integrated human immunodeficiency virus (HIV) treatment and prevention strategy among persons who inject drugs (PWID) in Indonesia, Ukraine, and Vietnam. We previously detected multiple HIV infection in 3 of 7 (43%) of seroconverters with 3-8 HIV strains per person. In this report, we analyzed multiple HIV infection and HIV superinfection (SI) in the HPTN 074 cohort. METHODS: We analyzed samples from 70 participants in Indonesia and Ukraine who had viral load >400 copies/mL at enrollment and the final study visit (median follow-up, 2.5 years). HIV was characterized with Sanger sequencing, next-generation sequencing, and phylogenetic analysis. Additional methods were used to characterize a rare case of triple-variant SI. RESULTS: At enrollment, multiple infection was detected in only 3 of 58 (5.2%) participants with env sequence data. SI was detected in only 1 of 70 participants over 172.3 person-years of follow-up (SI incidence, 0.58/100 person-years [95% confidence interval, .015-3.2]). The SI case involved acquisition of 3 HIV strains with rapid selection of a strain with a single pol region cluster. CONCLUSIONS: These data from a large cohort of PWID suggest that intrahost viral selection and other factors may lead to underestimation of the frequency of multiple HIV infection and SI events.

New PCR primers targeting the cytochrome b gene reveal diversity of Leucocytozoon lineages in an individual host.

Avian haemosporidian parasites have received considerable attention in ecology and evolution as a result of their wide distribution and ease of detection. However, conventional PCR-based detection methods may sometimes underestimate haemosporidian mixed infections, which are frequent in natural populations. This underestimation is due to differences in PCR sensitivity for detection of lineages within the mixed infections. Therefore, we designed new primers to amplify sequences that were not detected by the conventional primers and examined if our primers were useful for accurate detection of mixed infections. Blood samples were collected from 32 wild birds captured in Hokkaido, and 16 of these were positive for Leucocytozoon using the conventional primers, while 15 were positive using our primers. All positively amplified samples were sequenced, and we found that the conventional primers detected 16% (5/32) of multiple infections and none of them was a novel lineage, whereas our primers detected 44% (14/32) of multiple infections and ten of them were novel lineages. A phylogenetic analysis showed that the new primers can detect a wide range of Leucocytozoon lineages compared with that detected by the conventional primers. The results indicate that our primers are particularly suitable for revealing unique strains from multiple infections. Highly variable multiple infections in the same population of birds at the same location were found for the first time. We revealed a higher diversity of Leucocytozoon lineages in nature than expected, which would provide more information to better understand parasite diversity and host-vector interactions in wildlife.

Experimental Study on Primary Bird Co-Infection with Two Plasmodium relictum Lineages-pSGS1 and pGRW11.

BACKGROUND: Co-infections are common in the wild. Thus, studies focused on parasite interactions are essential. We aimed to (i) follow the development of two genetic lineages of Plasmodium relictum-pSGS1 and pGRW11-during single infections and co-infections and (ii) evaluate their impact on bird host health. MATERIALS: Twenty-four domestic canaries were allocated to four groups: two groups were infected with parasites of a single genetic lineage, one group was infected with parasites of both genetic lineages, and one group was considered as the control group. Parasitemia, the number of polychromatophils, changes in body weight, and hemoglobin levels were all quantified up to 32 days post-infection. RESULTS: Three birds infected with pSGS1 died within 20 days post-infection. The prepatent period and the peak of parasitemia did not differ significantly between groups. Differences in hemoglobin levels between the control and experimental groups were observed and there was an abnormal increase in the number of polychromatophils in infected birds. In all infected groups, correlations were detected between the number of polychromatophils and parasitemia (positive), and between the number of polychromatophils and hemoglobin levels (negative). CONCLUSION: This study shows that co-infection with two phylogenetically closely related P. relictum parasites does not alter overall parasitemia and does not cause higher virulence to the host.

Hypnozoite dynamics for Plasmodium vivax malaria: The epidemiological effects of radical cure.

Malaria is a mosquito-borne disease with a devastating global impact. Plasmodium vivax is a major cause of human malaria beyond sub-Saharan Africa. Relapsing infections, driven by a reservoir of liver-stage parasites known as hypnozoites, present unique challenges for the control of P. vivax malaria. Following indeterminate dormancy periods, hypnozoites may activate to trigger relapses. Clearance of the hypnozoite reservoir through drug treatment (radical cure) has been proposed as a potential tool for the elimination of P. vivax malaria. Here, we introduce a stochastic, within-host model to jointly characterise hypnozoite and infection dynamics for an individual in a general transmission setting, allowing for radical cure. We begin by extending an existing activation-clearance model for a single hypnozoite, adapted to both short- and long-latency strains, to include drug treatment. We then embed this activation-clearance model in an epidemiological framework accounting for repeated mosquito inoculation and the administration of radical cure. By constructing an open network of infinite server queues, we derive analytic expressions for several quantities of epidemiological significance, including the size of the hypnozoite reservoir; the relapse rate; the relative contribution of relapses to the infection burden; the distribution of multiple infections; the cumulative number of recurrences over time, and the time to first recurrence following drug treatment. We derive from first principles the functional dependence between within-host and transmission parameters and patterns of blood- and liver-stage infection, whilst allowing for treatment under a mass drug administration regime. To yield population-level insights, our analytic within-host distributions can be embedded in multiscale models. Our work thus contributes to the epidemiological understanding of the effects of radical cure on P. vivax malaria.

Development of a TaqMan-Probe-Based Multiplex Real-Time PCR for the Simultaneous Detection of Porcine Circovirus 2, 3, and 4 in East China from 2020 to 2022.

Porcine circovirus disease (PCVD) caused by porcine circovirus (PCV) is an important swine disease that is characterized by porcine dermatitis, nephropathy syndrome, and reproductive disorders in sows. However, disease caused by PCV2, PCV3, or PCV4 is hard to distinguish, so a rapid and sensitive detection method is urgently needed to differentiate these three types. In this study, four pairs of specific primers and the corresponding probes for PCV 2, -3, and -4, and porcine endogenous gene ß-Actin as the positive internal reference index, were designed to establish a TaqMan multiplex real-time PCR (qPCR) assay for the simultaneous differential diagnosis of different types of viruses. The results showed that this assay has good specificity and no cross-reactivity with other important porcine viral pathogens. Furthermore, it has high sensitivity, with a detection limit of 101 copies/µL, and good reproducibility, with intra- and inter-group coefficients of variation below 2%. Subsequently, 535 clinical samples of suspected sow reproductive disorders collected from Shandong, Zhejiang, Anhui, and Jiangsu provinces from 2020 to 2022 were analyzed using the established assay. The results showed that the individual positive rates of PCV2, PCV3, and PCV4 were 31.03%, 30.09%, and 30.84%, respectively; the mixed infection rates of PCV2 and PCV3, PCV2 and PCV4, and PCV3 and PCV4 were 31.03%, 30.09%, and 30.84%, respectively; the mixed infection rate of PCV2, PCV3, and PCV4 was 28.22%. This indicated that this assay provides a convenient tool for the rapid detection and differentiation of PCV2, PCV3, and PCV4 in pig farms in East China. Our findings highlight that there are different types of porcine circovirus infection in pig farms in East China, which makes pig disease prevention and control difficult.