Does a positive PCR result indicate active infection?
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A positive PCR result does not definitively indicate active infection, as demonstrated by various studies. PCR positivity can persist beyond symptom resolution, leading to challenges in determining infectivity post-recovery. While PCR can detect pathogens quickly, it may not always align with culture results, necessitating caution in interpretation. For instance, in COVID-19 cases, PCR positivity can outlast infectivity, with viral shedding declining significantly after the first week of illness. Therefore, a positive PCR should be considered alongside clinical context and possibly additional tests to accurately assess active infection status.
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| Not addressed in the paper. | |
| Yes, a positive PCR result in patients with acute toxoplasmosis suggests active disease, as demonstrated by the presence of Toxoplasma gondii DNA in blood samples. | |
12 Citations | Positivity on PCR does not always imply infectivity post-symptom resolution. PCR can remain positive after the infectious period, as seen in COVID-19 and influenza studies. |
| Not addressed in the paper. | |
| A positive PCR result targeting the positive RNA strand may not necessarily indicate active infection, as remnants can yield positive results post-recovery, unlike targeting the negative RNA strand. |
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