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HIV and AIDS
Published in Rae-Ellen W. Kavey, Allison B. Kavey, Viral Pandemics, 2020
Rae-Ellen W. Kavey, Allison B. Kavey
In the absence of specific treatment, 98% of those infected with HIV will develop full-blown AIDS by 10 years and die within 20 years post infection. During this entire time, testing for HIV-1 RNA can be measured in the plasma and tests for HIV are positive.68 At the end of the latency stage, patients may experience symptoms like recurrent fever, weight loss, gastrointestinal symptoms like chronic diarrhea, and muscle pain. Between 50% and 70% of people develop a prodrome of generalized, unexplained, non-painful enlargement of more than one group of lymph nodes lasting 3–6 months, as recognized by epidemiologists in the first years of the AIDS epidemic.16 The onset of symptoms – and therefore the shift in diagnosis from HIV infection to AIDS – reflects near-total destruction of the immune system. The timeline of HIV infection is shown in Figure 6.2.
Prevention, Screening, and Treatment of Sexually Transmitted Infections
Published in James M. Rippe, Lifestyle Medicine, 2019
Diagnosis of HIV is made by assessing for HIV antibody status and antigen status. Antibodies appear between two and 12 weeks after exposure. Acute infection is a manifestation of HIV viremia, with flu-like symptoms that last about four weeks. This may present as a nonspecific febrile illness or mononucleosis-like syndrome, with fever, lymphadenopathy, pharyngitis, rash, myalgias, mucocutaneous ulcers, or headach e. Fifty to 89% of patients are symptomatic with acute HIV infection.21 During this time, the person is very contagious with a high viral load. Next, during the latency stage, patients are generally asymptomatic and have low levels of virus in the blood, as it is inactive. This stage can last from two weeks to indefinitely, with mean duration of latency of 10 years. HIV then progresses to the final stage, or AIDS, when CD4 counts fall to less than 200 cells/mm of blood, and viral load is high. Opportunistic illness also defines this stage.
Immune-epidemiological parameters of the novel coronavirus – a perspective
Published in Expert Review of Clinical Immunology, 2020
The 2019-nCoV spreads during the clinical latency stage, and therefore, classical models for epidemic outbreaks do not apply to the particular case of 2019-nCoV. Also, an average reproductive number of 3.11 indicates that the average number of secondary cases with the 2019-nCoV is increasing [15]. The official data estimate that the average clinical latency stage lasts 7 days or more and it is longer than the median incubation period of 5.2 days (2–14 days) [15]. Thus, there is a promising point that the treatment of symptomatic individuals can be useful. However, it should be mentioned that the reproduction number varies over time depending on the estimation models. The average reproduction number estimated by stochastic methods, mathematical methods, and exponential growth are 2.44, 4.2, and 2.67, respectively [16]. Moreover, simulation methods predict that with continuing efforts Wuhan would achieve a reproduction number of less than one soon [17]. Here, we frame immunogenetic explanations for the epidemiological dynamics of COVID-19.
Disparities Between HIV Testing Levels and the Self-Reported HIV-Negative Status of Sexually Active College Students
Published in The Journal of Sex Research, 2019
Edmond Pui Hang Choi, Janet Yuen Ha Wong, Daniel Yee Tak Fong
The present findings also have some clinical implications. First, the low prevalence of HIV testing among sexually active students is a public health concern, especially among sexually active students who use condoms inconsistently and MSM. Without HIV testing, students might not be aware that they are HIV positive, especially during the clinical latency stage, when most infected people experience no symptoms. It has been suggested that those with undiagnosed HIV disproportionately transmit HIV to others (Lieber et al., 2006). We believe that public health campaigns and interventions to encourage HIV counseling and testing among high-risk populations (MSM, sex workers, people with multiple sexual partners) are definitely needed, because these groups are at high risk of HIV infection. In addition, school-based interventions should be deployed to increase awareness of the importance of HIV testing, and university health services should provide a discrimination-free and stigma-free environment for HIV counseling and testing. In addition, clinicians should not rely solely on self-reported HIV data for screening and risk stratifications in routine clinical practice. If resources permit, biological testing should be used.
Pathogenicity and virulence of human T lymphotropic virus type-1 (HTLV-1) in oncogenesis: adult T-cell leukemia/lymphoma (ATLL)
Published in Critical Reviews in Clinical Laboratory Sciences, 2023
Sanaz Ahmadi Ghezeldasht, David J. Blackbourn, Arman Mosavat, Seyed Abdolrahim Rezaee
Notably, in many HTLV-1-infected subjects, TAX is the main immunodominant antigen for the host-specific CTL responses, which provide immune pressure on the virus [123]. In such a situation, the virus must down-regulate or turn off Tax expression and enter the latency stage. In the absence of the TAX molecule, the question can be raised: which viral transcription factor induces the IL-2 and IL-2Ra growth factors to maintain ATLL cells? Along with evading the host immune responses by silencing Tax, HTLV-1 still has the potency to induce clonal expansion and leukemogenesis progression.