The impact of respiratory coinfections in COVID-19 is still not well understood despite the growing evidence that consider coinfections greater than expected. A total of 295 patients older than 18 years of age, hospitalized with a confirmed diagnosis of moderate/severe pneumonia due to SARS-CoV-2 infection (according to definitions established by the Ministry of Health of Peru) were enrolled during the study period. A coinfection with one or more respiratory pathogens was detected in 154 (52.2%) patients at hospital admission. The most common coinfections were Mycoplasma pneumoniae (28.1%), Chlamydia pneumoniae (8.8%) and with both bacteria (11.5%); followed by Adenovirus (1.7%), Mycoplasma pneumoniae/Adenovirus (0.7%), Chlamydia pneumoniae/Adenovirus (0.7%), RSV-B/Chlamydia pneumoniae (0.3%) and Mycoplasma pneumoniae/Chlamydia pneumoniae/Adenovirus (0.3%). Expectoration was less frequent in coinfected individuals compared to non-coinfected (5.8% vs. 12.8%). Sepsis was more frequent among coinfected patients than non-coinfected individuals (33.1% vs. 20.6%) and 41% of the patients who received macrolides empirically were PCR-positive for Mycoplasma pneumoniae and Chlamydia pneumoniae. / National Research Foundation of Korea / Revisión por pares

Torque-teno viruses (TTVs) are small ubiquitous non-enveloped single-stranded circular DNA viruses. Since their discovery in a post-transfusion hepatitis patient, they have been isolated in several vertebrate hosts with over 90% prevalence, including swine. They have been detected in the environment, water sources, human drugs, vaccine and blood product as contaminants. Intriguingly, the role of TTVs in human disease causation is still not fully understood. Several epidemiological studies have associated TTVs to human diseases, like cancers, hepatitis, and autoimmune diseases, but no clear link between infection and clinical disease has been demonstrated yet. In contrast, experimental studies done in pigs demonstrated that swine TTVs (TTSuVs) could an act as sole pathogens. Other studies also demonstrated that TTSuVs could exacerbate symptoms of other viral pathogens in coinfections. Here, we showed that TTSuV1 could be zoonotic, as we detected TTSuV1 DNA in human serum samples. We also showed that TTSuV1 could replicate in human immune cells, and consequently suppress their ability to respond to immune stimuli. Further in-vivo studies, to elucidate host immune regulation by TTSuVs, showed a delayed antibody response and minimal viremia. Also, we found that viral sensing could be limited to interferon-inducing sensors (DHX36), while upregulation of PD-1 could demonstrate how these viruses may establish chronic infections. In another study, we showed the use of our novel recombinant TTSuV1 culture system to study the synergistic interactions between TTSuV1 and porcine circovirus 1 (PCV1). When both viruses were cultured together in-vitro, their respective viral titers were increased, compared to the single virus infections. We also demonstrated that increased in-vitro replication of TTSuV1 could be relying on expression of PCV1 replicase. In addition, molecular mechanisms were used to explain this synergistic relationship; a strong promoter activity by the putative major promoter of TTSuV1 was shown to be blocked PCV1 and TTSuV1 replicase proteins, but protein-DNA interaction assays need further optimizations to demonstrate physical interaction between these viruses. In conclusion, our result showed new information about TTSuV1 transmission, pathogenesis, host innate immune regulation, and their role in coinfections.

Background: Coinfections with multiple types of human papillomavirus (HPV) are a common occurrence among HPV-infected individuals, but the clinical significance and etiology of these infections remain unclear. Though current evidence suggests that women with coinfections have increased HPV exposure (i.e. more sexual partners), it is also hypothesized that these women may represent a subgroup with increased HPV susceptibility, though this has been rarely studied to date. Purpose: The purpose of this project was to examine the occurrence, determinants and dynamics of HPV coinfections in a cohort of university students in order to explore the relationship(s) between coinfections, lifestyle factors and immunological susceptibility. Methods: This project is based on a secondary analysis of data from the McGill-Concordia Cohort, a longitudinal study of the natural history of HPV infection in 621 female university students in Montreal, Quebec. Participants were followed for 2 years at 6-month intervals. At each visit, cervical specimens were collected for cytology and HPV testing, and women completed a questionnaire about lifestyle and risk behaviours. Two definitions of coinfections were used: cumulative coinfection over follow-up and concurrent coinfection at each visit. Kaplan-Meier techniques were used to estimate incidence and duration of coinfections and multiple logistic regression was used to identify determinants of coinfections and associations between coinfections and squamous intraepithelial lesions (SIL). Results: More than half of the cohort became infected with HPV and of those, over 60% acquired multiple HPV types over follow-up. Incidence of coinfections was significantly increased among HPV-infected women at enrollment. The most important determinant of coinfection occurrence was number of sexual partners (both lifetime and new), though some genes of the immune response (HLA-DQB1*06:02, HLA-G*01:01:03 and HLA-G*01:01:05) were also significant predictors. Women with coinfections, particularly those with 4+ HPV types, also had longer infection durations and greatly increased odds of SIL. Conclusions: Women with coinfections acquire new HPV types at an increased rate and have greater HPV persistence and occurrence of SIL, which may indicate immunological susceptibility. HPV coinfections mainly occur due to increased sexual activity but a decreased immune response to the virus may also be involved in a subset of women. / Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2011-04-21 01:04:26.265

The protozoan Cryptosporidium parvum is one of the major causative pathogens of diarrhoea in young ruminants; therefore, it causes economic losses and impairs animal welfare. Besides C. parvum, there are many other non-infectious and infectious factors, such as rotavirus, Escherichia coli, and Giardia duodenalis, which may lead to diarrhoeic disease in young livestock. Often, more than one infectious agent is detected in affected animals. Little is known about the interactions bet-ween simultaneously occurring pathogens and their potential effects on the course of disease. In this review, a brief overview about pathogens associated with diarrhoea in young ruminants is presented. Furthermore, information about coinfections involving Cryptosporidium is provided.