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COVID studies

A new, small study shows COVID can spread to heart, brain and other parts of the body

A new study by the NIH shows that COVID-19 can spread to the heart and brain in a matter of days after infection and can survive for months in organs. The study, which very small in size with only 44 total individuals, involved complete autopsies conducted on patients that had died from COVID-19. A study this small cannot be representative of the entire population, but that doesn’t mean that all findings should be discarded.

While there is of course some risk in taking vaccines or medication of any kind, there is also a danger in contracting COVID-19. The chance of dying from COVID or having a serious vaccine side effect are both incredibly small for the great majority of everyone, especially healthy individuals. However, nobody yet knows the true long term impact of COVID-19. What scientists are continuing to research, such as with this study, is how COVID-19 can impact the body as a whole, including the brain. Brain fog for example is one side effect reported by many who have experienced COVID and recovered. The virus can also spread to almost every organ system in the body according to the , which is why some experience “long COVID” according to the study authors.

The study paper states:

Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), has well described pulmonary and extrapulmonary manifestations1-3, including multiorgan failure and shock among severe and fatal cases. Some survivors experience Post-Acute Sequelae of SARS-CoV-2 (PASC) – also known as Long COVID—with cardiovascular, pulmonary, and neurological manifestations with or without functional impairment. While autopsy studies of fatal COVID-19 cases support the ability of SARS-CoV-2 to infect multiple organs3, extra-pulmonary organs often lack histopathological evidence of direct virally-mediated injury or inflammation. The paradox of extra-pulmonary infection without injury or inflammation raises many pathogen- and host-related questions. These questions include, but are not limited to: What is the burden of infection within versus outside of the respiratory tract? What cell types are infected across extra-pulmonary tissues, and do they support SARS-CoV-2 infection and replication? In the absence of cellular injury and 96 inflammation in extra-pulmonary tissues, does SARS-CoV-2 persist, and if so, over what interval? Does SARS-CoV-2 evolve as it spreads to and persists in different anatomical compartments?

To inform these pathogen-focused questions and to evaluate for the presence or absence of associated histopathology in matched tissue specimens, we performed extensive autopsies on a diverse population of 44 individuals who died from or with COVID-19 up to 230 days following initial symptom onset. Our approach focused on timely, systematic, and comprehensive tissue sampling and preservation of adjacent tissue samples for complementary analyses. We performed droplet digital polymerase chain reaction (ddPCR) for sensitive detection and quantification of SARS-CoV-2 gene targets in all tissue samples collected. To elucidate SARS-CoV-2 cell-type specificity and validate ddPCR findings, we performed in situ hybridization (ISH) broadly across sampled tissues. Immunohistochemistry (IHC) was used to further validate cell-type specificity in the brain where controversy remains on the regional distribution and cellular tropism of SARS-CoV-2 infection. In all samples where SARS-CoV-2 RNA was detected by ddPCR, we performed qRT-PCR to detect subgenomic (sg)RNA, an assay suggestive of recent virus replication. We confirmed the presence of replication-competent SARS-CoV-2 in extrapulmonary tissues by virus isolation in cell culture. Lastly, in six individuals, we measured the diversity and anatomic distribution of intra-individual SARS-CoV-2 variants using high-throughput, single-genome amplification and sequencing (HT-SGS).

We categorized autopsy cases of SARS-CoV-2 infection as “early” (n=17), “mid” (n=13), or “late” (n=14) by illness day (D) at the time of death, being ≤D14, D15-D30, or ≥D31, respectively. We defined persistence as presence of SARS-CoV-2 RNA among late cases. Due to the extensive tissue collection, we analyzed and described the results in terms of grouped tissue categories as the following: respiratory tract; cardiovascular; lymphoid; gastrointestinal; renal and endocrine; reproductive; muscle, skin, adipose, & peripheral nerves; and brain.

For additional information, you can read the study paper here.

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