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The Viruses
Published in Julius P. Kreier, Infection, Resistance, and Immunity, 2022
Smallpox produces an acute infection. After inhalation the virus first multiplies in mucosal cells of the upper respiratory tract and then infection spreads to the regional lymph nodes. A mild transient viremia is followed by infection of the liver, spleen, and lungs. In these organs multiplication continues for about twelve to sixteen days. Few symptoms are present at this stage, and it is thus referred to as the “incubation” period. The secondary viremia that ensues then produces generalized symptoms, including fever, pain, headache, malaise, and rash. Epidermal cells then become infected and the virus multiplies over an additional two-week period. During this phase, there is necrosis of epidermal cells and leukocyte infiltration leading to formation of the characteristic skin pustules, or pocks. Pocklike lesions may also form in the liver and other soft tissues. In nonfatal cases, the skin lesions eventually resolve by “crusting” and scarification, and the infection terminates with the development of permanent immunity.
Other viral infections
Published in Hung N. Winn, Frank A. Chervenak, Roberto Romero, Clinical Maternal-Fetal Medicine Online, 2021
Mumps is usually a benign and self-limited disease. Following infection and incubation, viremia occurs. The disease is asymptomatic in 30% to 60% of patients. Most symptomatic patients experience moderate debilitation (46). Typical symptoms include fever, malaise, and swelling of one or both parotid glands. If the parotid glands are swollen, other salivary glands may also be involved. Viral replication occurs in multiple organs as the virus is disseminated. Pancreatitis, arthritis, and myocarditis are rare complications (45). Approximately 20% of postpubertal males will develop orchitis. Infection of the thyroid and breast may occur in the postpubertal females.
Neuroinfectious Diseases
Published in Philip B. Gorelick, Fernando D. Testai, Graeme J. Hankey, Joanna M. Wardlaw, Hankey's Clinical Neurology, 2020
Jeremy D. Young, Jesica A. Herrick, Scott Borgetti
In approximately 5% of individuals, a second “major” viremia occurs, causing symptoms that are not easily distinguished from those induced by many other viral infections, such as headache, pharyngitis, fever, nausea, vomiting, abdominal pain, listlessness, malaise, and fatigue. This viral syndrome is known as the “minor illness” or abortive poliomyelitis.
An overview of letermovir: a cytomegalovirus prophylactic option
Published in Expert Opinion on Pharmacotherapy, 2019
Giuseppe Gerna, Daniele Lilleri, Fausto Baldanti
A phase 2 study on LTV preemptive therapy in kidney transplant recipients reported that DNAemia remains positive for long periods despite response to LTV [67], and monitoring of virological response to pre-emptive therapy may be difficult. Monitoring of HCMV infections in HSCT recipients treated prophylactically with LTV using conventional laboratory assays such as DNAemia by real-time PCR may raise concerns on results interpretation. In fact, the mechanism of action of LTV, which allows intracellular accumulation of viral DNA and proteins, might lead to misleading PCR signals due to released viral DNA from degrading cells into bloodstream. As a result, it is recommended to enroll only HCMV-seropositive patients with negative HCMV DNAemia in clinical trials for LTV prophylaxis. A careful enrollment as well as appropriate PCR data evaluation is mandatory to avoid erroneous interpretation as prophylaxis failure [60,63] through HCMV DNAemia detection. In other words, we advice to carefully use the term ‘viremia’ which is only relevant to detection and quantification of infectious virus in blood as opposite to ‘DNAemia’ which can include both replication competent and replication incompetent viral DNA determination. To solve equivocal cases, we suggest quantification of infectious virus by using the shell-vial assay.
An adult case of human parvovirus B19 infection developed ACPA-positive rheumatoid arthritis
Published in Modern Rheumatology Case Reports, 2019
Toshihiro Tono, Tomohiro Hosoda, Ryohei Nagata, Satoshi Kawaai, Ryo Hazue, Atsuko Murota, Hiroaki Taguchi, Mitsuo Sakamoto, Yasuo Ohsone, Yutaka Okano
Because PVB 19 infection is mainly an epidemic infection via the respiratory system in children and infants, the history of contact with an infected child aided the diagnosis. Children living together with our patient also had infectious erythema. The clinical course follows a bimodal process that shows fever due to viremia with upper respiratory tract symptoms (phase 1), followed approximately 1 week later by skin rash and joint symptoms (phase 2) [6]. The incidence of arthritis seen in phase 2 frequently is as low as 50%–80% in adults [7,8], and approximately 5% in children. There are many cases of asymmetric large arthritis (especially in the knee) in children, but adults complain of PIP and MCP arthritis and finger stiffness in addition to polyarthritis, which often requires differentiation from RA [9]. The IgM anti-PVB 19 antibody becomes positive in phase 2. In our case, IgM anti-PVB 19 antibodies were positive with a typical clinical course, so we diagnosed PVB 19 infection.
The clinical use of parvovirus B19 assays: recent advances
Published in Expert Review of Molecular Diagnostics, 2018
Following primary infection, B19V, or at least B19V DNA, can be detected in peripheral blood for prolonged periods, and can then persist in a wide range of tissues, probably lifelong [11,12], raising questions about the actual relevance and pathogenetic implications of these findings. In peripheral blood, viremia measured as the detection of viral DNA is considered a marker of active infection. However, low-levels of viral DNA can be detected for extended period of times following a documented past infection [29,30], and be a rather common finding in the normal population as well [31]. Presence of viral DNA in blood has been documented in subjects with congenital or acquired immunodeficiency, in patients receiving chemotherapy for hematological or solid malignancies [32,33] and in the course of immunosuppressive treatments in bone marrow [34,35] or solid organ transplant recipients [36–39]. Presence of viral DNA is interpreted as indicating the occurrence of persistent infections, although not necessarily associated with underlying pathogenetic mechanisms and with clinically relevant situations. Recently, it has been demonstrated that an analytical differentiation can be introduced between the detection of viral DNA within virions, thus related to an active productive infection, and circulating free viral DNA, possibly released from sites of persistence in the tissues, in a concept similar to that of liquid biopsy [40]. The clinically utility of such differentiation has probably just begun to be appreciated [41].