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.

Herpes simplex virus (HSV) infections can be treated with direct acting antivirals like acyclovir and foscarnet, but long-term use can lead to drug resistance, which motivates research into broadly-acting antivirals that can provide a greater genetic barrier to resistance. Photodynamic inactivation (PDI) employs a photosensitizer, light, and oxygen to create a local burst of reactive oxygen species that inactivate microorganisms. The botanical plant extract Orthoquin TM is a powerful photosensitizer with antimicrobial properties. Here we report that Orthoquin also has antiviral properties. Photoactivated Orthoquin inhibited herpes simplex virus type 1 (HSV-1) and herpes simplex virus type 2 (HSV-2) infection of target cells in a dose-dependent manner across a broad range of sub-cytotoxic concentrations. HSV inactivation required direct contact between Orthoquin and the inoculum, whereas pre-treatment of target cells had no effect. Orthoquin did not cause appreciable damage to viral capsids or premature release of viral genomes, as measured by qPCR for the HSV-1 genome. By contrast, immunoblotting for HSV-1 antigens in purified virion preparations suggested that higher doses of Orthoquin had a physical impact on certain HSV-1 proteins that altered protein mobility or antigen detection. Orthoquin PDI also inhibited the non-enveloped adenovirus (AdV) in a dose-dependent manner, whereas Orthoquin-mediated inhibition of the enveloped vesicular stomatitis virus (VSV) was light-independent. Together, these findings suggest that the broad antiviral effects of Orthoquin-mediated PDI may stem from damage to viral attachment proteins. facilitate attachment and entry into host cells. While HSV-1 and HSV-2 are similar, they share onlỹ 55% nucleotide identity. Lytic HSV infection of a cell begins with initial attachment to negatively charged cell surface heparan sulfate and chondroitin sulfate glycosaminoglycans, followed by stable attachment of viral glycoproteins to cell surface receptors and fusion of the viral envelope to the plasma membrane or internal membranes [2] . Fusion of viral and host membranes enables delivery of the viral nucleocapsid and tegument proteins to the cytoplasm. After the HSV nucleocapsid arrives at the nucleus and delivers the viral genome, HSV genes are expressed in an ordered temporal cascade. Viral egress requires primary envelopment of the genome-containing capsid at the inner nuclear membrane, fusion with the outer nuclear membrane and final envelopment at the trans-Golgi network. Mature virions then exit through the cellular secretory system. All stages of the HSV replication cycle offer potential targets for direct-acting antiviral (DAA) therapy. However, DAAs can be undermined by the emergence of drug resistant mutant viruses. Anti-HSV DAAs acyclovir and foscarnet offer examples of the hazards of drug resistance. These drugs interrupt HSV genome replication by different mechanisms of action. Acyclovir is a nucleoside analogue prodrug that selectively targets HSV infected cells through the action of the HSV thymidine kinase (TK) enzyme, which efficiently phosphorylates acyclovir and facilitates incorporation into nascent viral DNA genomes by the HSV DNA polymerase enzyme; incorporation of acyclovir into viral DNA terminates genome replication [3] . By contrast, the pyrophosphate analogue foscarnet blocks viral genome replication by directly inhibiting HSV DNA polymerase activity [4] . Though resistance to acyclovir occurs at a low prevalence (≤1%) in immunocompetent patients [5], immunocompromised patients experience much higher rates (4-10%) [6] . Unsurprisingly, resistance to acyclovir, and its derivatives, and to foscarnet, has been mapped to mutations in the viral thymidine kinase and the DNA polymerase catalytic subunit, respectively [7] . Currently, Abreva (n-docosanol) is the only over-the-counter topical antiviral for herpes labialis. Abreva is incorporated into the cellular plasma membrane and prevents fusion steps essential for HSV-1 entry into epithelial cells [8] . However, it must be applied repeatedly throughout the day due to rapid plasma membrane turnover and the subsequent loss of n-docosanol [9] . This host-targeted antiviral mechanism prevents development of viral resistance, but Abreva is only approved for perioral lesions, so there is a still a gap in treatment for lesions in other areas of the body. Like Abreva, there is potential for more broadly-acting antiviral drugs that exploit the physical structure of the HSV virion and block early stages of infection, such as attachment and penetration. In this study, we explored the potential of the plant-derived photosensitizing agent Orthoquin TM to mediate photodynamic inactivation (PDI) [10] of virions. The clinical utility of Orthoquin PDI of oral biofilms is an area of active investigation and there is clear potential for wider range of clinical applications. The basis of PDI is the photodynamic effect, which has been exploited in photodynamic therapy (PDT) [11, 12] for treatment of cancers [13] and age-related macular degeneration [14] . In PDT, photosensitizer compounds when exposed to visible light react with oxygen to generate reactive oxygen species (ROS) that include singlet oxygen [15] . ROS damage proteins, nucleic acids and lipids, which can lead to cell death. Some of the most well-known photosensitizing molecules for PDT are based on a tetrapyrrolic core and are found in naturally occurring pigments, such as heme, chlorophyll, and bacteriochlorophyll [16] . The accepted phototoxic mechanism for these types of photosensitizers involves the formation of an excited triplet state upon light absorption that can participate in electron (Type 1) or energy (Type 2) transfer processes. Type 1 electron transfer reactions typically lead to the formation of radical species like superoxide or hydroxyl radicals, whereas Type 2 energy transfer produces cytotoxic singlet oxygen. It is possible for a photosensitizer to initiate both Type 1 and 2 photoprocesses simultaneously, depending on the specific chemistry of the photosensitizing agent and its environment [16] . Due to the high reactivities and short lifetimes of oxidizing molecules, it is expected that only viral structures in close proximity to activated photosensitizing compounds will be affected.
Photodynamic Inactivation of Herpes Simplex Viruses

We summarize herein the results of various virologic studies of acute otitis media (AOM) conducted at our site over a ten -year period. Among 566 children with AOM, respiratory syncytial virus (RSV) was the most common virus identified in either middle ear fluid or nasal wash; it was found in 16% of all children and 38% of virus-positive children. Seventy-one percent of the children with RSV were one year of age or older, which was significantly older than all other viruses combined (P = 0.045). RSV infection was associated with the common bacterial pathogens causing AOM. Past efforts to develop vaccines for RSV have emphasized prevention of lower respiratory tract infection in infants, which is a more serious problem but less common than AOM. Our results suggest that RSV vaccines that work only against infection in older children may have value in preventing AOM, the most common pediatric disease.
ROLE OF RESPIRATORY SYNCYTIAL VIRUS IN ACUTE OTITIS MEDIA: IMPLICATIONS FOR VACCINE DEVELOPMENT

Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) is the most important endemic pathogen in the U.S. swine industry. Despite control efforts involving improved biosecurity and different vaccination protocols, the virus continues to circulate and evolve. One of the foremost challenges in its control is high levels of genetic and antigenic diversity. Here, we quantify the co-circulation, emergence and sequential turnover of multiple PRRSV lineages in a single swine-producing region in the United States over a span of 9 years (2009)(2010)(2011)(2012)(2013)(2014)(2015)(2016)(2017). By classifying over 4,000 PRRSV sequences (open-reading frame 5) into phylogenetic lineages and sub-lineages, we document the ongoing diversification and temporal dynamics of the PRRSV population, including the rapid emergence of a novel sub-lineage that appeared to be absent globally pre-2008. In addition, lineage 9 was the most prevalent lineage from 2009 to 2010, but its occurrence fell to 0.5% of all sequences identified per year after 2014, coinciding with the emergence or re-emergence of lineage 1 as the dominant lineage. The sequential dominance of different lineages, as well as three different sublineages within lineage 1, is consistent with the immune-mediated selection hypothesis for the sequential turnover in the dominant lineage. As host populations build immunity through natural infection or vaccination toward the most common variant, this dominant (sub-) lineage may be replaced by an emerging variant to which the population is more susceptible. An analysis of patterns of non-synonymous and synonymous mutations revealed evidence of positive selection on immunologically important regions of the genome, further supporting the potential that immune-mediated selection shapes the evolutionary and epidemiological dynamics for this virus. This has important implications for patterns of emergence and re-emergence of genetic variants of PRRSV that have negative impacts on the swine industry. Constant surveillance on PRRSV occurrence is crucial to a better understanding of the epidemiological and evolutionary dynamics of co-circulating viral lineages. Further studies utilizing whole genome sequencing and exploring the extent of cross-immunity between heterologous PRRS viruses could shed further light on PRRSV immunological response and aid in developing strategies that might be able to diminish disease impact.

Temporal Dynamics of Co-circulating Lineages of Porcine Reproductive and Respiratory Syndrome Virus