# COVID-19 and Parasitic Co-Infection: A Hypothetical Link to Pulmonary Vascular Disease

## TL;DR

This paper explores a possible link between parasitic co-infections and increased risk of pulmonary vascular disease in patients with COVID-19.

## Contribution

It proposes hypothetical pathophysiological mechanisms linking parasitic co-infections and PVD in the context of COVID-19.

## Key findings

- PVD prevalence in severe SARS-CoV-2 infections is estimated at 22%, but its predictive value is unclear.
- Co-infections like schistosomiasis, HIV, and tuberculosis may worsen PVD outcomes in the context of COVID-19.
- Future experimental studies are needed to confirm the proposed pathophysiological pathways.

## Abstract

Background/Objectives: Before the Coronavirus disease 2019 (COVID-19) era, the global prevalence of pulmonary arterial hypertension (PAH) was between 0.4 and 1.4 per 100,000 people. The long-term effects of protracted COVID-19 associated with pulmonary vascular disease (PVD) risk factors may increase this prevalence. According to preliminary data, the exact prevalence of early estimates places the prevalence of PVD in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection at 22%, although its predictive value remains unknown. PVD caused by COVID-19 co-infections is understudied and underreported, and its future impact is unclear. However, due to COVID-19/co-infection pathophysiological effects on pulmonary vascularization, PVD mortality and morbidity may impose a genuine concern—both now and in the near future. Based on reported studies, this literature review focused on the potential link between COVID-19, parasitic co-infection, and PVD. This review article also highlights hypothetical pathophysiological mechanisms between COVID-19 and parasitic co-infection that could trigger PVD. Methods: We conducted a systematic literature review (SLR) searching peer-reviewed articles, including link between COVID-19, parasitic co-infection, and PVD. Results: This review hypothesized that multiple pathways associated with pathogens such as underlying schistosomiasis, human immunodeficiency virus (HIV), pulmonary tuberculosis (PTB), pulmonary aspergillosis, Wuchereria bancrofti, Clonorchis sinensis, paracoccidioidomycosis, human herpesvirus 8, and scrub typhus coupled with acute or long COVID-19, may increase the burden of PVD and worsen its mortality in the future. Conclusions: Further experimental studies are also needed to determine pathophysiological pathways between PVD and a history of COVID-19/co-infections.