Highly pathogenic avian influenza affects vultures' movements and breeding output.

An exceptional highly pathogenic avian influenza (HPAI) outbreak due to H5N1 virus genotypes belonging to clade 2.3.4.4.b has been affecting birds worldwide since autumn 2021.1,2,3 Mortality caused by viral infection has been well documented in poultry and more recently in wild birds, especially in seabird-breeding colonies.4,5,6 However, there is a critical lack of knowledge about how terrestrial birds deal with HPAI virus infections in terms of behavior and space use, especially during the breeding season.7,8,9 Understanding how birds move when they are infected could help evaluate the risk of spreading the virus at a distance among other populations of wild or domestic birds, this latter risk being especially important for commensal bird species. Through long-term GPS tracking, we described the changes in daily movement patterns of 31 adult griffon vultures Gyps fulvus in two French sites in 2022 compared with 3 previous years. In spring 2022, 21 vultures at both sites showed periods of immobility at the nest, during 5.6 days on average. Positive serological status of 2 individuals confirmed that they had been infected by HPAI viruses. Death was recorded for 3 of the 31 tracked individuals, whereas all others recovered and returned quickly to their foraging routine, although at least 9 birds failed breeding. Such immobility patterns and death rates were never observed in previous years and were not related to weather conditions. The high immobility behavior of infected birds could reduce the risks of transmission. The observed vulnerability to HPAI viruses questions the resistance of endangered vulture species worldwide if infected.

Prevalence of and risk factors for symptomatic dry eye disease in Singapore.

BACKGROUND: The aim of this study was to describe the prevalence and risk factors of symptomatic dry eye disease (SDED) in Singapore. METHODS: A cross-sectional dry eye survey was carried out using the McMonnies dry eye questionnaire. Members of the public were interviewed at the 46 (out of 62) randomly-selected mass rapid transit (MRT) stations and their vicinity. A total of 1,004 questionnaires were collected from participants aged between 15 and 83 years. Symptomatic dry eye disease (SDED) was defined as at least one of five self-reported symptoms that were reported as often or constantly. Non-dry eye (NDE) subjects were those with no related symptoms reported. Prevalence of symptomatic dry eye disease in the studied population and confidence interval (CI) were calculated. Risk factors were also evaluated using logistic regression analysis at 95% CI. RESULTS: The prevalence for symptomatic dry eye disease was found to be 12.3 per cent with prevalence greater in females than males. Symptomatic dry eye disease was significantly associated with contact lens wear (odds ratio [OR] 2.96, 95% CI: 1.81 to 4.83), those having had previous treatment for dry eye (OR 2.09, 95% CI: 1.33 to 3.29), those taking medication (OR 1.84, 95% CI: 0.99 to 3.44), those with unusual sensitivity of eyes (OR 3.04, 95% CI: 1.92 to 4.83), constant mucous membrane dryness (OR 4.11, 95% CI: 1.62 to 10.45) and irritation on waking (OR 2.38, 95% CI: 1.34 to 4.22). Smoking was not found to be associated with symptomatic dry eye disease. CONCLUSION: Singapore has a symptomatic dry eye disease prevalence of 12.3 per cent and was associated with contact lens wear, those who had previous treatment for dry eye, medication, those having unusual sensitivity of eyes, mucous membrane dryness and waking irritation. These new data will be of value to the eye-care community in Singapore and elsewhere.