Can COVID-19 be a sexually transmitted disease? Posterity will judge.

Dear Editor,

The Coronavirus disease 2019 (COVID‐19) Pandemic outbreak, declared on March 11, 2020 by the World Health Organization (WHO), has placed a strain on health care systems all around the world, and even developed countries are struggling to organize a timely and effective response.

Until now, the precise mode of transmission of SARS‐CoV‐2 (Severe Acute Respiratory Syndrome‐Coronavirus‐2) has still not been completely described; however, the main route is through human‐to‐human transmission via droplets. Multiple studies have concluded that asymptomatic carriers can spread the virus unknowingly, thus leading governments to implement very restrictive rules of social distancing, also recommending the avoidance of multiple sexual intercourses.

The knowledge of all possible modes of transmission of SARS‐CoV‐2 infection is the key to improving both the identification of the asymptomatic population and the necessary isolation measures in order to further flatten the curve.

We operate in a free service for the prevention and treatment of sexually transmitted diseases (STDs), and owing to the lack of publications concerning this specific population, we are speculating that a certain percentage of the asymptomatic population could be spreading SARS‐CoV‐2 through sexual contact (vaginal, anogenital, and orogenital).

The presence of SARS‐CoV‐2 RNA in the feces of COVID‐19 patients (66.67%) has already been demonstrated in recent studies in Wuhan, without being statistically related to gastrointestinal symptoms and/or disease severity. Furthermore, 64.29% of these patients showed a persistent positivity for RNA search by polymerase chain reaction (PCR) in the stool following viral clearance (negative nasopharyngeal and oropharyngeal swabs).

From a molecular point of view, the ACE2 (angiotensin‐converting enzyme 2) receptor, largely expressed along the gastrointestinal mucous membranes, has been demonstrated as the cell entry for SARS‐CoV2. ,

The human testis has also been indicated as a potential target of SARS‐CoV‐2, due to the expression of ACE2 receptor in the Leydig cells and cells of the seminiferous tubules, leading to potential defects in spermatogenesis. In addition, some authors suggest that the human testis could provide another potential route of infection. Moreover, the positivity for SARS‐CoV‐2 on vaginal swab raises the possibility of both sexual and mother‐to‐child transmission, although further studies are needed on these issues since no definitive proofs have been found.

Therefore, it is possible that people presenting STD risk factors (multiple partners, HIV infected patients, homosexual, drug addicted, unprotected sexual intercourse, unprotected anal intercourse, etc) could be more susceptible to SARS‐CoV2 infection. This eventuality would expose STD patients to becoming asymptomatic vehicles of the virus, even after negative pharyngeal swab.

An example supporting the hypothesis of sexually transmitted SARS‐CoV‐2 infection consists in the 2016 to 2017 Hepatitis A outbreak in the European MSM population (men who have sex with men). Although the main mode of transmission of HAV is the orofecal route, the rapid international spread of Hepatitis A among this population had been correlated with high‐risk sexual behaviors.

Over the past weeks, we have observed seven cases of confirmed SARS‐CoV‐2 infection in our MSM population. This additional data seems to support our speculation; however, rectal swabs for the execution of SARS‐CoV‐2 PCR are not still available in our STDs clinic.

In conclusion, it would be useful to confirm the possibility of other alternative ways of viral transmission. If these speculations are confirmed, we should consider implementing an anal swab in all COVID‐19 patients, also in those with negative pharyngeal swab.

A further step would be adding SARS‐CoV‐2 serology, pharyngeal, anal and vaginal swabs to our usual STD screening also in the asymptomatic population, in order to identify positive cases and to confirm the SARS‐CoV‐2 orogenital route of transmission.

CONFLICT OF INTEREST

The authors have no conflict of interest to declare.

AUTHOR CONTRIBUTIONS

Valeria Gaspari, Annalisa Patrizi, Federico Bardazzi, and Anna Lanzoni contributed to the letter conception and design. The first draft of the manuscript was written by Valeria Gaspari, Gionathan Orioni, and Filippo Viviani, and all authors commented on previous versions of the manuscript.