RESUMEN
Purpose: To analyze the presence of severe acute respiratory syndrome coronavirus 2 (SARS?CoV?2) in tears/conjunctival epithelium and assess the cytomorphological changes in the conjunctival epithelium of coronavirus disease 2019 (COVID?19) patients. Methods: In this pilot study, patients with moderate to severe COVID?19 were recruited from the COVID ward/intensive care unit of the institute. Tears and conjunctival swabs were collected from COVID?19 patients and sent to the virology laboratory for reverse transcription polymerase chain reaction (RT?PCR) testing. Conjunctival swabs were used to prepare smears, which underwent cytological evaluation and immunocytochemistry for SARS?CoV?2 nucleocapsid protein. Results: Forty?two patients were included. The mean age of participants was 48.61 (range: 5–75) years. Seven (16.6%) patients tested positive for SARS?CoV?2 ribonucleic acid in tears samples, four (9.5%) of which were positive on conjunctival swab by RT?PCR in the first test. Cytomorphological changes were observed significantly more in smears from patients with positive RT?PCR on tear samples, including bi?/multi?nucleation (p = 0.01), chromatin clearing (p = 0.02), and intra?nuclear inclusions (p < 0.001). One case (3.2%) showed immunopositivity for SARS?CoV?2; this patient had severe disease and the lowest Ct values for tear and conjunctival samples among all positive cases. Conclusion: Conjunctival smears from patients with COVID?19 revealed cytomorphological alterations, even in the absence of clinically significant ocular infection. However, viral proteins were demonstrated within epithelial cells only rarely, suggesting that although the conjunctival epithelium may serve as a portal for entry, viral replication is possibly rare or short?lived.
RESUMEN
Background: Delhi, a city in north India, has so far witnessed several reported outbreaks of dengue. Dengue in Delhi from being epidemic is slowly changing towards being endemic and hyper-endemic. Circulating type of the virus is also changing over the years. In the absence of an effective vaccine, dengue prevention to a major extent relies on virological surveillance, and development of effective, locally adapted control programmes. In the present study, we tried to identify the between-year non-epidemic serotype of dengue virus circulating in Delhi, during 2010–11. Methods: Acute-phase samples were collected from the patients attending the Institute of Liver & Biliary Sciences, New Delhi, India. Dengue diagnosis was done using WHO case definitions. All the samples were subjected to Dengue NS1 Ag ELISA and modified nested RT-PCR. Results: A total of 75 acute-phase samples were received, of which 19 (25.3%) were positive for dengue NS1 antigen. Dengue RT-PCR was positive in 14.6% (11/75) samples. All the RT-PCR isolates were of DENV-1 serotype. No case of concomitant infection with more than one serotype was observed. Median age of involvement was 23 yr (range10–86). Maximum number of cases were seen in the age group of 21–30 yr. Male to female ratio was 1.2 : 1. Maximum number of suspected dengue cases (n=79) was seen during September and October. Conclusions: DENV-1 was circulating in Delhi in the year 2010–11 in non-epidemic period following reported predominance of DENV-3 and co-circulation of all dengue serotypes in the epidemic years 2003, 2006 and 2007.