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Background: The novel coronavirus SARS-CoV-2 is the etiological agent of COVID-19. This virus has become one of the most dangerous in recent times with a very high rate of transmission. At present, several publications show the typical crown-shape of the novel coronavirus grown in cell cultures. However, an integral ultramicroscopy study done directly from clinical specimens has not been published., Methods: Nasopharyngeal swabs were collected from 12 Cuban individuals, six asymptomatic and RT-PCR negative (negative control) and six others from a COVID-19 symptomatic and RT-PCR positive for SARS CoV-2. Samples were treated with an aldehyde solution and processed by scanning electron microscopy (SEM), confocal microscopy (CM) and, atomic force microscopy. Improvement and segmentation of coronavirus images were performed by a novel mathematical image enhancement algorithm., Results: The images of the negative control sample showed the characteristic healthy microvilli morphology at the apical region of the nasal epithelial cells. As expected, they do not display virus-like structures. The images of the positive sample showed characteristic coronavirus-like particles and evident destruction of microvilli. In some regions, virions budding through the cell membrane were observed. Microvilli destruction could explain the anosmia reported by some patients. Virus-particles emerging from the cell-surface with a variable size ranging from 80 to 400 nm were observed by SEM. Viral antigen was identified in the apical cells zone by CM., Conclusions: The integral microscopy study showed that SARS-CoV-2 has a similar image to SARS-CoV. The application of several high-resolution microscopy techniques to nasopharyngeal samples awaits future use., (© 2021. The Author(s).)

Background: An association between HPV infection and progression to anal squamous intraepithelial lesions (ASIL) has been established, specifically in high-risk populations such as HIV-infected men. In this population, anal cancer is one of the most common non-AIDS-defining malignancies., Methods: A cross-sectional study to detect anal lesions and HPV infection was performed. Anal mucosa samples were collected from 56 HIV-infected men from Cuba. The cytological diagnosis was done according to Bethesda 2001 System. HPV DNA detection was determined by qPCR for six high-risk HPV types and end point PCR for low-risk HPV types (6 and 11). The end point PCR with nucleotide sequencing technique was achieved to detect other genotypes of HPV not included in the qPCR in those samples negative for HPV- 6 and 11 or negative for the six genotypes identified in the qPCR., Results: Cytological diagnosis identified 53 of 56 (95%) men with abnormal anal cytology. Among those, 26% (14/53) had atypical squamous cells of undetermined significance (ASC-US), 4% (2/53) had atypical squamous cells of undetermined significance cannot exclude high-grade lesions (ASC-H), 64% (34/53) had low-grade squamous intraepithelial lesions (LSIL), and 6% (3/53) had high-grade squamous intraepithelial lesions (HSIL). HPV DNA was detected in 89% (50/56) of men and 79% had at least one of the high-risk HPV types. HPV- 16 was the most common genotype (52%), while HPV-18 was the most frequently detected genotype in men with HSIL. We found statistically significant differences in the HPV viral loads with respect to the cytology results ( p  = 0.0006) and that the practice of receptive anal sex was a risk factor for anal HPV infection ( p  = 0.032)., Conclusion: This study shows a high prevalence of ASIL and high-risk HPV infections in the study group and is the first study showing the distribution of HPV genotypes in HIV infected Cuban men with abnormal anal cytology. This information may be of importance for local decision makers to improve prevention strategies, including the introduction of HPV vaccine in Cuba.

In Cuba, previous reports have shown an increase of epidemic KS, reaching a total of 120 cases by the end of 2007, despite the use of HAART. To evaluate and compare the role of human herpes virus 8 (HHV-8) viral loads in different compartments of AIDS-related Kaposi's sarcoma (AIDS-KS) patients real-time polymerase chain reaction (RT-PCR) was used to determine the genome copy number of HHV-8 in plasma, saliva, tissue and peripheral blood mononuclear cells (PBMC) of 49 AIDS-KS patients. Overall, 98% of AIDS-KS patients harbored detectable HHV-8. HHV-8 could be detected in 91.6% of KS tissue lesions showing the highest viral load (median log = 3.14 copies/100 ng DNA) followed by saliva and PBMC which were positive in 78%, and 69.2%; respectively. In contrast, HHV-8 was detected in only 37% of plasma samples, which also showed lower viral loads. Men who had sex with men (MSM) were more likely to have three-times higher HHV-8 genome copies in KS lesions when compared with tissues from heterosexuals individuals (OR 3; 95% CI 1.1 to 12.5). These results emphasize the systemic nature of HHV-8-infection and demonstrate the possible role of saliva in HHV-8 transmission among MSM.