Abstract
Sir,
Thank you for your interest in our study. The prevalence of the feline coronavirus (FCoV) infection varies among different geographical regions and test methods used. Pratelli et al (2009) detected antibodies in Turkey 1 against FCoV whereas our study detected the shedding of the virus through the feces. Although seropositivity is associated with virus shedding, 2 and the amount of the titer is correlated with replication and the amount of the virus in the intestines, 3 these two criteria (seropositivity and virus shedding) represent different aspects of the infection.
Although the rate of FCoV shedding in Malaysian catteries (84%) was high, 4 it was within the range reported elsewhere in multi-cat households (75–100%). 5 Several risk factors for FCoV infection have been identified such as young age, breed disposition, immune status, pregnancy and any factor that increases stress-like diseases, such as surgery and high density living in the cattery. 3 In one study, deaths from feline infectious peritonitis (FIP) were more frequent in fall and winter, and on the basis of analysis of cattery records, the number of deaths varied yearly. 6 However, currently there is no evidence of the relation between tropical climate and FCoV infection. In addition, no report of FCoV shedding from other tropical regions is available to compare with our findings.
Generally, we know that FCoV is a relatively fragile virus; the viral particles remain stable in feces for about 10 days 7 and it can persist in the environment for 3–7 weeks, 8 but there is no report about the climatic effects on the incident rate of FCoV infection.
The numbers of tested cats in both studies (44 cats in the polymerase chain reaction assay and 100 cats in the serological survey) are indeed small, however, the results are in agreement with previous studies with bigger sample size reporting that most of FCoV infections are asymptomatic and only 1–5% of infected cats develop FIP. 3