In this task, you're given a paragraph from the research paper and your task is to generate a suitable title for the research paper based on the given paper. Under 100 words is a good title length.

Bacterial and viral co-infections of the respiratory tract are life-threatening and present a global burden to the global community. Staphylococcus aureus, Streptococcus pneumoniae, and Streptococcus pyogenes are frequent colonizers of the upper respiratory tract. Imbalances through acquisition of seasonal viruses, e.g., Influenza A virus, can lead to bacterial dissemination to the lower respiratory tract, which in turn can result in severe pneumonia. In this review, we summarize the current knowledge about bacterial and viral co-infections of the respiratory tract and focus on potential experimental models suitable for mimicking this disease. Transmission of IAV and pneumonia is mainly modeled by mouse infection. Few studies utilizing ferrets, rats, guinea pigs, rabbits, and non-human primates are also available. The knowledge gained from these studies led to important discoveries and advances in understanding these infectious diseases. Nevertheless, mouse and other infection models have limitations, especially in translation of the discoveries to humans. Here, we suggest the use of human engineered lung tissue, human ex vivo lung tissue, and porcine models to study respiratory co-infections, which might contribute to a greater translation of the results to humans and improve both, animal and human health.
Port d'Entree for Respiratory Infections -Does the Influenza A Virus Pave the Way for Bacteria?

Purpose: Despite their controversial role, corticosteroids (CS) are frequently administered to patients with H1N1 virus infection with severe respiratory failure secondary to viral pneumonia. We hypothesized that invasive pulmonary aspergillosis (IPA) is a frequent complication in critically ill patients with H1N1 virus infection and that CS may contribute to this complication. Methods: We retrospectively selected all adult patients with confirmed H1N1 virus infection admitted to the intensive care unit (ICU) of two tertiary care hospitals from September 2009 to March 2011. Differences in baseline factors, risk factors, and outcome parameters were studied between patients with and without IPA. Results: Of 40 critically ill patients with confirmed H1N1, 9 (23 %) developed IPA 3 days after ICU admission. Five patients had proven and four had probable IPA. Significantly more IPA patients received CS within 7 days before ICU admission (78 versus 23 %, p = 0.002). IPA patients also received significantly higher doses of CS before ICU admission [hydrocortisone equivalent 800 (360-2,635) versus 0 (0-0) mg, p = 0.005]. On multivariate analysis, use of CS before ICU admission was independently associated with IPA [odds ratio (OR) 14.4 (2.0-101.6), p = 0.007]. Conclusions: IPA was diagnosed in 23 % of critically ill patients with H1N1 virus infection after a median of 3 days after ICU admission. Our data suggest that use of CS 7 days before ICU admission is an independent risk factor for fungal superinfection. These findings may have consequences for clinical practice as they point out the need for increased awareness of IPA, especially in those critically ill H1N1 patients already receiving CS.
Invasive pulmonary aspergillosis is a frequent complication of critically ill H1N1 patients: a retrospective study

Infectious bursal disease (IBD) continues to pose potential threat to poultry industry all over the world. The disease can spell disaster not only through its infection but also by break of immunity in chickens vaccinated for other diseases. l-Arginine, a ubiquitous, semi-essential amino acid has emerged as an imunostimulant from variety of human and animal studies. In the present study, we demonstrate the stimulatory effects of l-arginine on intestinal intraepithelial lymphocyte (iIELs) functions as well as on systemic immune response in chickens orally vaccinated with live intermediate plus (IP) strain of IBD vaccine. Challenge studies with virulent IBDV revealed complete (100%) protection in IP + l-arginine group compared with 80% protection recorded in IP strain vaccinated chickens. Functional activities of iIELs evaluated by cytotoxicity assay demonstrated significantly high percentage cytotoxicity in IP + l-arginine groups compared with IP group (P < 0.05). Proliferative response of iIELs against IBDV antigen and Con-A was also significantly higher in IP + l-arginine group. Similar results were obtained with peripheral blood mononuclear cell blastogenic response to IBDV and Con-A analyzed as an indicator of systemic cell-mediated immune response. Orally administered IP strain vaccine elicited good antibody titres in both the groups, IP and IP + l-arginine, however, the antibody titres were significantly higher in IP + l-arginine group compared with IP vaccinated group (P < 0.05). These results clearly demonstrate that l-arginine stimulates intestinal and systemic immune response against IBDV.
l-Arginine stimulates intestinal intraepithelial lymphocyte functions and immune response in chickens orally immunized with live intermediate plus strain of infectious bursal disease vaccine