Neurological pathophysiology of SARS-CoV-2 and pandemic potential RNA viruses: a comparative analysis.

SARS-CoV-2 has infected hundreds of millions of people with over four million dead, resulting in one of the worst global pandemics in recent history. Neurological symptoms associated with COVID-19 include anosmia, ageusia, headaches, confusion, delirium, and strokes. These may manifest due to viral entry into the central nervous system (CNS) through the blood-brain barrier (BBB) by means of ill-defined mechanisms. Here, we summarize the abilities of SARS-CoV-2 and other neurotropic RNA viruses, including Zika virus and Nipah virus, to cross the BBB into the CNS, highlighting the role of magnetic resonance imaging (MRI) in assessing presence and severity of brain structural changes in COVID-19 patients. We present new insight into key mutations in SARS-CoV-2 variants B.1.1.7 (P681H) and B.1.617.2 (P681R), which may impact on neuropilin 1 (NRP1) binding and CNS invasion. We postulate that SARS-CoV-2 may infect both peripheral cells capable of crossing the BBB and brain endothelial cells to traverse the BBB and spread into the brain. COVID-19 patients can be followed up with MRI modalities to better understand the long-term effects of COVID-19 on the brain.

Viral infections and implications for male reproductive health.

Viral infections have haunted humankind since times immemorial. Overpopulation, globalization, and extensive deforestation have created an ideal environment for a viral spread with unknown and multiple shedding routes. Many viruses can infect the male reproductive tract, with potential adverse consequences to male reproductive health, including infertility and cancer. Moreover, some genital tract viral infections can be sexually transmitted, potentially impacting the resulting offspring's health. We have summarized the evidence concerning the presence and adverse effects of the relevant viruses on the reproductive tract (mumps virus, human immunodeficiency virus, herpes virus, human papillomavirus, hepatitis B and C viruses, Ebola virus, Zika virus, influenza virus, and coronaviruses), their routes of infection, target organs and cells, prevalence and pattern of virus shedding in semen, as well as diagnosis/testing and treatment strategies. The pathophysiological understanding in the male genital tract is essential to assess its clinical impact on male reproductive health and guide future research.

The Zika virus: Lurking behind the COVID-19 pandemic?

WHAT IS KNOWN AND OBJECTIVE: The sudden and extensive outbreak of coronavirus (SARS-CoV-2) has overshadowed another developing viral threat: the Zika flavivirus. Of particular concern is that pregnant women can pass Zika virus to the foetus, and there is a strong implication of an association between Zika virus infection and foetal microcephaly. Currently, there is no vaccine, and there is no cure. METHODS: Published literature and Internet sources were searched for information related to Zika virus, its transmission, its clinical presentation and sequalae, prevention and implications (practice and regulatory) for healthcare providers. The identified English sources were reviewed, assessed and synthesized. Emphasis was placed on providing an overview of the problem, and identification of unmet needs and future directions. RESULTS AND DISCUSSION: Zika virus poses a major challenge for healthcare providers, particularly in areas unaccustomed to it, since it is transmitted to humans by the vector Aedes aegypti mosquito. The outbreak impacts every healthcare provider, because every provider is required to report cases of Zika infection to their state or local health agencies--whether the infection is confirmed or merely suspected. Since the virus has become a worldwide crisis, healthcare providers will need to work across national boundaries and medical disciplines in order to educate patients about Zika symptoms and the mosquito vector. Until further information is known, infected patients (male and female) are being advised to avoid conceiving a child. WHAT IS NEW AND CONCLUSION: Until a vaccine is developed or effective treatment for Zika virus is discovered, healthcare providers must be AVP (aware, vigilant and proactive) in order to lessen the spread and impact of the implicated devastating birth defects (microcephaly) and other neurological disorders (eg Guillain-Barré Syndrome) of this infection. Unfortunately, many knowledge gaps exist. There is an urgent need for a reliable, inexpensive diagnostic test, an effective treatment and an approved and readily available vaccine.