Increased globalization and more frequent interactions led to COVID19 sweeping through the globe in a few month. The introduction of countermeasures in different countries and the generational changes the virus has undergone over the past three years allowed China to gradually loosen its COVID-19 precautions on December 26, 2022, after a comprehensive assessment of the possible consequences. There was a steady increase of Omicron infection amongst the Chinese population from this point on and the symptoms associated with COVID-19 were not only limited to the respiratory system, but also to the digestive16 and nervous systems17. Many male patients have reported a link between this omicron infection and decreased male sexual function, and many are concerned about whether their reproductive function may be affected by Omicron infection. To answer these questions, we explored the relationship between Omicron and erectile function, ejaculatory function and sexual experience in men from different perspectives, and we also collected the results of semen analysis before and after Omicron infection in some patients in an attempt to explore the effects of Omicron infection on male semen quality.
ED is the inability to maintain or achieve an erection sufficient for satisfactory sexual intercourse. To further investigate the effect of omicron infection on erectile function in men, we calculated the IEEF-5 scores of each patient before and after Omicron infection and categorized them as 21–30 (no ED), 12–21 (mild ED), 8–11 (moderate ED) and < 7 (severe ED), according to the scale. Statistical analysis was performed, and the results proved that there was a significant difference in erectile function in men before and after infection with Omicron, and that infection with Omicron contributed to the development of erectile dysfunction to some extent. Several studies have been conducted to discuss the correlation between COVID-19 infections and male erectile function. SARS-CoV-2 viral infections not only causes respiratory damage, but may also have serious effects on the male patients' reproductive system which regulate many physiological processes. Even though it appears that erectile function deteriorates after COVID-19 infection, the function tends to improve over time18 Patients with COVID-19 have a high risk and prevalence of ED, which may be driven primarily by anxiety, and attention should be paid to patients' erectile function when treating COVID-1919. Some researchers have also characterized the histopathology of tissue from patients who recovered from symptomatic COVID-19 infection, finding that the COVID-19 virus is present in the penis long after the initial infection in human20. Interestingly, an article suggested that PDE5 inhibitors, therapeutic agents for erectile function, may target potential targets of COVID-19 due to their anti-inflammatory, antioxidant, immune response modulating and anti-apoptotic properties21 Meanwhile, a cross-sectional study showed that COVID-19 vaccination did not affect male sexual function, including erectile function22. However, no studies were found that examined the effects of infection with Omicron on male erectile function.
In order to investigate the risk factors for ED due to Omicron infection, we conducted multivariate logistic regression analysis and finally found that "education", "smoking or not", "body temperature during infection", "hospitalization or not during infection", "concern about sexual function" and "age" were possible risk factors. We speculate that there may be differences in the acquisition of knowledge about prevention, so that education becomes a risk factor, while smoking history, temperature, and hospitalization or not may respond to the severity of symptoms from different aspects, especially endothelial cell disorders due to severe inflammation as indicated by high temperature, which has been studied and proven to be a possible factor contributing to ED.
Since male sexual function includes not only erectile function but also ejaculatory function and sexual experience. There are very few studies on the effects of COVID-19 infection on premature ejaculation and sexual experience, and no articles have been found on the relationship with Omicron either. As premature ejaculation is an important male disease, it is necessary to explore its relationship with Omicron, so we found that 11.4% of men had premature ejaculation or worsened premature ejaculation after infection with Omicron based on the scores of PDET before and after infection with Omicron obtained from the questionnaire, but the results of the difference analysis revealed that the incidence of premature ejaculation before and after infection was not statistically significant. The same approach was used to analyze the scores of the ASEX scale and it was found that 31.5% of the patients experienced a decrease in sexual experience after infection with Omicron, with statistically significant differences before and after infection. Multivariate logistic regression was used to assess risk factors, and it was found that "education", "whether or not you had urinary tract problems in the past 12 months", "body temperature during infection "and "concern about sexual function" were found to be risk factors for decreased sexual experience due to Omicron infection. A number of studies have examined the impact of anxiety during the COVID-19 epidemic on the occurrence of sexual dysfunction. During the COVID-19 epidemic, a certain percentage of adult men were at increased risk for premature sexual ejaculation. The postponed fertility treatment brought about by the COVID19 epidemic has led to an increase in the proportion of patients with premature ejaculation, probably due to anxiety23. A study of the complications of COVID-19 infection in patients with epilepsy noted that outbreaks of COVID-19 led to an increased propensity for depression in patients with epilepsy and also negatively impacted sexual experience24.
Many researchers have speculated that in addition to being present in the respiratory system and transmitted by droplets, SARS-COV-2 virus may also be present in the reproductive system and transmitted by body fluids, and many studies have emerged to test this speculation. Investigation of the molecular details of SARS-CoV-2 infection has been rapidly initiated, and several key facts are already known. Viral entry requires SARS-CoV-2 spike-in(S) glycoprotein to bind to host ACE2. Host TMPRSS2 is then required to cleave the viral S protein to induce a conformational change that allows permanent fusion of the viral and host cell membranes25. The results of single-cell sequencing confirmed that co-expression of ACE2 and TMPRSS2 was not detected in testicular cells (including spermatozoa)26. A prospective longitudinal cohort provided direct experimental evidence that the male reproductive system may be targeted and disrupted by COVID-19 infection by assessing semen ACE84 activity, inflammatory and oxidative stress markers, apoptotic variables, and semen quality parameters27.
On the basis of questionnaire surveys to explore male sexual function, we collected the semen analysis results of 247 patients before and after infection in the andrology clinic of the hospital, mainly from the semen volume, sperm concentration, total number of sperm, PR a + b sperm forward movement, sperm survival rate and proportion of normal sperm are used to comprehensively evaluate the patient's semen quality. Based on the 247 semen analysis results obtained, we found the impact of COVID-19 infection on semen analysis data including semen concentration, semen activity and PR a + b sperm forward movement, which is consistent with the results of some previous basic research. An autopsy of semen specimens from China for sperm parameters and immune factors also revealed impaired spermatogenesis and the development of autoimmune orchitis, presumably due to elevated levels of local immune responses. Many analyses of sperm parameters in semen samples have shown a significant correlation between COVID-19 infection and decreased sperm quality28. The results of semen analysis for a median observation time of 56 and 78 days also suggest that COVID-19 has adverse but potentially reversible consequences on sperm quality29. Additional analyses of oxidative stress markers and sperm DNA for semen samples suggest that increased DNA fragmentation and decreased semen quality in men may be the result of an imbalance between semen precursors and antioxidant components after COVID-1930.
In this study, we investigated for the first time the effects of Omicron on sexual function and semen quality in Chinese men by collecting male sexual function questionnaires from men infected with Omicron and analyzing the semen of some patients, and also found adverse effects of Omicron infection on male erectile function, male sexual experience and male semen quality. Anxiety and worry were involved as confounding factors, while academic qualifications, body temperature during infection, and anxiety during infection were risk factors for changes in semen quality with Omicron. Of course, our study has some drawbacks: It is an observational study, which limits the inference of causes; The distribution of the subjects collected is not evenly scattered throughout the provinces of China, but may be concentrated in certain provinces; Due to the small sample size of semen analysis, the correlation between COVID-19 infection and semen quality of patients was not found; The study is limited by the number of questions and does not explore in more detail the effects of various emotional and psychiatric disorders on the process; The collection of data on the scale before and two weeks after the novel coronavirus infection does not allow the analysis of changes in male sexual function and semen quality after a long period of Omicron infection. Pre-infection and acute phase data were collected simultaneously during the acute phase and there may be memory bias.