Fig 1.

Fig 2.

The mechanisms and probability of SARS-CoV-2 transmission
| Mechanism | Location in the body or transmission route | Transmission probability |
|---|---|---|
| ACE2 and TMPRSS2 protease | Heart, kidneys, tests, lungs, nasopharynx, smooth muscle cells, placenta | The risk of transmission is the highest during early pregnancy and decreases toward delivery |
| Perinatal transmission | Healthcare services and procedures | Extremely low risk of viral transmission |
| Breastfeeding | Breast milk | Extremely low risk of viral transmission |
| Sexual intercourse | Semen | Very low risk of viral transmission |
| NRP-1 | Hofbauer cells, endothelial cells, smooth muscle cells, adipocytes, Sertoli cells, placenta | This is the most likely route of SARS-CoV-2 transmission |
| Macrophages and monocytes | Various tissues – especially placental macrophages | Very high risk of viral transmission |
Pathologies and clinical manifestations
| Level of changes | Pathology | Clinical manifestation |
|---|---|---|
| Placental |
|
|
| Systemic |
|