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Coltivirus is a virus genus (of the family Reoviridae) that infects both vertebrates and invertebrates. It contains the agent that causes Colorado Lyme fever. The Colorado tick fever virus can lead to fever, shivers, headache, photophobia, myalgia, arthralgia, and fatigue. Children are especially susceptible to developing a hemorrhagic disease. Leukopenia containing both lymphocytes and neutrophils … Read more
Hanta Virus Structure of Hanta Virus Genome Structure of Hanta Virus Epidemiology of Hanta Virus Transmission of Hanta Virus Replication cycle of hantaviruses Pathogenesis of Hanta Virus The recognition of hantaviruses by macrophages (M) or dendritic cells (DCs) induces proinflammatory cytokines, which alter the phenotype of endothelial cells (ECs) from anti- to pro-adhesive. Pro-adhesive ECs … Read more
Structure of Measles Virus Genome Structure of Measles Virus Epidemiology of Measles Virus Transmission of Measles Virus Replication of Measles Virus Pathogenesis of Measles Virus Clinical manifestations of Measles Virus Complications If not properly treated, measles can result in chronic complications such as pneumonia, encephalitis, etc. Other possible complications include: Laboratory diagnosis Methods of Measles … Read more
What is Lytic Cycle? Definition of Lytic Cycle The lytic cycle is a phase of viral reproduction wherein a virus infects a host cell, utilizes the cell’s machinery to replicate, and subsequently causes the cell to burst (lyse), releasing new virions to infect other cells. Bacteriophage(virus) Life cycle of bacteriophage Steps of the Lytic Cycle … Read more
What is Lysogenic Cycle? Definition of Lysogenic Cycle The lysogenic cycle is a viral replication process in which a virus integrates its genetic material into the host cell’s genome, allowing it to remain dormant and propagate without immediately destroying the host. This dormant viral DNA, known as a prophage, can later be activated to initiate … Read more
What are Viruses? Definition of Viruses Viruses are submicroscopic infectious agents that can only replicate within the living cells of a host organism, capable of infecting all forms of life. They consist of genetic material (DNA or RNA) encased in a protein coat and, in some cases, an external lipid envelope. Are Viruses Living or … Read more
Human Papillomaviruses Classification On the basis of DNA homology, tissue tropism, and relationship with oncogenesis, the HPVs have been categorised into 16 groups (A–P), encompassing at least 70 kinds, containing a total of at least 100 types. Human infections caused by papovaviruses Papillomavirus Polyomavirus Morphology of Human papillomaviruses Human papillomaviruses have the following characteristics: Viral … Read more
What is Parvovirus? Classification of Parvovirus Parvovirus B19 Parvovirus B19, or B19 virus, is the causal agent of erythema infectiosum (“fifth disease”; it was fifth of the six identified exanthematous disorders of childhood), a minor viral sickness of children, as well as polyarthralgia–arthritis syndrome in immunocompetent adults. Morphology of Parvovirus B19 B19 viruses manifest the … Read more
Coronaviruses are a type of virus that can cause illness, ranging from the common cold to more severe diseases such as Middle East Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome (SARS). Coronaviruses are so named because they have a crown-like appearance when viewed under a microscope. They are primarily transmitted from person to person … Read more
SARS-CoV-2 is the virus that causes the disease COVID-19 (coronavirus disease 2019). It is a highly infectious disease that can spread from person to person through respiratory droplets or close contact. The virus was first identified in Wuhan, China in December 2019 and has since spread to become a global pandemic. Symptoms of COVID-19 can … Read more
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