Purpose To determine the expressions of SARS-CoV-2 receptor angiotensin-converting enzyme 2 (ACE2) and type II transmembrane serine protease (TMPRSS2) genes in human and mouse ocular cells and comparison to other tissue cells. Methods Human conjunctiva and primary pterygium tissues were collected from pterygium patients who underwent surgery. The expression of ACE2 and TMPRSS2 genes was determined in human primary conjunctival and pterygium cells, human ocular and other tissue cell lines, mesenchymal stem cells as well as mouse ocular and other tissues by reverse transcription-polymerase chain reaction (RT-PCR) and SYBR green PCR.Results RT-PCR analysis showed consistent expression by 2 ACE2 gene primers in 2 out of 3 human conjunctival cells and pterygium cell lines. Expression by 2 TMPRSS2 gene primers could only be found in 1 out of 3 pterygium cell lines, but not in any conjunctival cells. Compared with the lung A549 cells, similar expression was noted in conjunctival and pterygium cells. In addition, mouse cornea had comparable expression of Tmprss2 gene and lower but prominent Ace2 gene expression compared with the lung tissue. Conclusion Considering the necessity of both ACE2 and TMPRSS2 for SARS-CoV-2 infection, our results suggest that conjunctiva would be less likely to be infected by SARS-CoV-2, whereas pterygium possesses some possibility of SARS-CoV-2 infection. With high and consistent expression of Ace2 and Tmprss2 in cornea, cornea rather than conjunctiva has higher potential to be infected by SARS-CoV-2. Precaution is necessary to prevent possible SARS-CoV-2 infection through ocular surface in clinical practice.

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Keratoconus is an ectatic corneal dystrophy and is a leading indication for corneal transplantation surgery worldwide. The disease was first described in detail more than 150 years ago by Dr John Nottingham, but the understanding of the disease and its management have undergone significant changes over the last few decades. Corneal specialists have adopted new techniques and technologies for the effective management of keratoconus, while adhering to the age-old concepts of contact lens fitting and penetrating keratoplasty. Lamellar keratoplasty has been revived with improved outcomes and devices such as intracorneal ring segments are being used to treat cases of early keratoconus effectively. This review article discusses the current scenario on the surgical as well as non-surgical management of keratoconus with a focus on the established, novel and emerging treatment modalities.

Higher levels of outdoor activity were associated with less myopic refraction in primary school students in the inner city of Beijing. Near work activity was not found to be associated with refraction at either school level.

Viral conjunctivitis caused by adenovirus is the most common infectious conjunctivitis. Adenoviruses are highly contagious pathogens. The modes of transmission are mainly through hand to eye contact, ocular secretions, respiratory droplets, and contact with ophthalmic care providers and their medical instruments. The most frequent manifestation of ocular adenoviral infection is epidemic keratoconjunctivitis, followed by pharyngoconjunctival fever. Epidemic keratoconjunctivitis is also the most severe form and presents with watery discharge, hyperemia, cheosis, and ipsilateral lymphadenopathy. Pharyngoconjunctival fever is characterized by abrupt onset of high fever, pharyngitis, bilateral conjunctivitis, and periauricular lymph node enlargement. Isolated follicular conjunctivitis without corneal or systemic involvement also occurs. The rate of clinical accuracy in diagnosing viral conjunctivitis is less than 50%. Rapid diagnostic tests now being used decrease unnecessary antibiotic use. Treatment for viral conjunctivitis is mostly supportive. The majority of cases are self-limited, and no treatment is necessary in uncomplicated cases.

Careful case selection is required before deciding on the surgical management plan in cases with band keratopathy. Chelation is a cost-effective and straightforward procedure. An excimer laser PTK, although costly, can provide a smooth corneal surface. Combination treatment using amniotic membrane is reserved for selected cases to enhance epithelial healing.

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Myopia is the most common human eye disorder and it results from complex genetic and environmental causes. The rapidly increasing prevalence of myopia poses a major public health challenge. Here, the CREAM consortium performs a joint meta-analysis to test single-nucleotide polymorphism (SNP) main effects and SNP × education interaction effects on refractive error in 40,036 adults from 25 studies of European ancestry and 10,315 adults from 9 studies of Asian ancestry. In European ancestry individuals, we identify six novel loci (FAM150B-ACP1, LINC00340, FBN1, DIS3L-MAP2K1, ARID2-SNAT1 and SLC14A2) associated with refractive error. In Asian populations, three genome-wide significant loci AREG, GABRR1 and PDE10A also exhibit strong interactions with education (P<8.5 × 10−5), whereas the interactions are less evident in Europeans. The discovery of these loci represents an important advance in understanding how gene and environment interactions contribute to the heterogeneity of myopia.