Global seroprevalence and factors associated with seropositivity for feline immunodeficiency virus (FIV) in cats: A systematic review and meta-analysis

The feline immunodeficiency virus (FIV) is a retrovirus of the Lentivirus genus, distributed worldwide, that causes persistent infection with a significant impact on the cats' health. Due to the importance of this infection in feline medicine, this pioneering study aimed to obtain an integrated estimate of the global seroprevalence of FIV in cats and to characterize the factors associated with this infection. Four electronic databases were screened for observational studies with FIV seroprevalence in cats published globally for this systematic review and meta-analysis. The initial search method returned 873 studies, of which 113 met all predefined criteria and were therefore included in this review. Meta-analysis with general data was performed, and a combined global seropositivity of 9.43 % (95 % CI: 8.24 % - 10.78 %) was found. Seropositivity was 14.34 % (95 % CI = 10.92 % - 18.61 %) in Asia, 11.90 % (95 % CI = 9.82 % - 14.34 %) in Oceania, 10.90 % (95 % CI = 5.71 % - 19.82 %) in Central America, 9.43 % (95 % CI = 6.95 % - 12.66 %) in South America, 9 % (95 % CI = 0 - 80 %) in Africa, 8.98 % (95 % CI = 7.31 % - 10.98 %) in Europe, and 5.93 % (95 % CI = 4.33 % - 8.07 %) in North America. Meta-analysis of factors associated with seropositivity demonstrated that FIV seroprevalence was higher in male (Prevalence ratio [PR] = 2.53, 95 % CI = 2.16 - 2.95), adult (PR = 2.83, 95 % CI = 2.24 - 3.56), unowned status (PR = 1.47, 95 % CI = 1.07 - 2.03), sick status (PR = 2.46, 95 % CI = 1.97 - 3.06), and cats with outdoor access (PR = 4.38, 95 % CI = 2.26 - 8.47). The results demonstrated that FIV is globally distributed and has a high seroprevalence in some geographical areas. Information compiled from this research is relevant to understanding the worldwide epidemiology of FIV. It presents the potential to contribute to the planning of strategies focused on controlling and reducing cases in cat populations.