Search

This study critically reviews the literature on the prevalence and genotypic distribution of Bovine Leukemia Virus (BLV) in Asia, specifically targeting enzootic bovine leukosis, a chronic disease affecting cattle’s life and milk production along with reduced fat yield, that causing economic losses due to increased susceptibility to pathogens. European countries are eradicating BLV but Asia has a high prevalence, particularly in Asian cattle. Enzootic bovine leukosis (EBL) has distinct clinical stages: asymptomatic, persistent lymphocytosis, and lymphosarcoma. It typically occurs in adult animals, with 60% being asymptomatic during the aleukemic stage, 30% developing persistent lymphocytosis, and 5% developing lymphoma. Databases like PubMed and Google Scholar were used to search molecular and prevalence studies from 2000-2024, focusing on Asian countries. Prevalence of bovine leukosis (BL) in Asia varies significantly, with high rates in central and eastern regions. BLV is a global disease, has increased in Asia with highest prevalence in central Asia about 40.0–84.0% (Kazakhstan), 35% in Eastern Asia (Japan), and 58.3% in Southeast Asia (Thailand). BLV genotypes G1, G4, G6, G7, G12, G3, G4, G6, G7, and G10 are prevalent in various regions of Asia, with G1 being most prevalent globally. These genotypes might be spread due to animal trading, and animal domestication, affecting various countries. This review provides the current status of enzootic bovine leukosis in Asia, emphasising the need for a closed trading system to control the disease.

Naegleria fowleri, commonly known as the “brain-eating amoeba,” is an opportunistic, free-living protozoan responsible for primary amoebic meningoencephalitis (PAM), a rare but almost invariably fatal infection of the central nervous system. This thermophilic amoeba thrives in warm freshwater environments such as lakes, hot springs, and poorly maintained swimming pools. It can survive under high temperatures, making it more prevalent in regions with warm climates and developed countries, including Australia, Europe, and the United States. This review summarizes current evidence on the global prevalence, clinical presentation, diagnostic challenges, and treatment strategies related to N. fowleri infections. Epidemiological data indicate that approximately 26.4% of global freshwater sources contain Naegleria species, with the highest prevalence recorded in the Americas at 33.2%. Infected individuals typically present with acute symptoms such as severe headache, high fever (101–105°F), neck stiffness, seizures, altered mental status, and coma, with disease progression often resulting in death within one to two weeks of symptom onset. Despite advances in supportive care and antimicrobial therapy, the case fatality rate remains over 90%. Conventional diagnostic methods include microscopy, culture, serology, imaging, and molecular techniques such as real-time PCR; however, delays in diagnosis often hamper timely treatment. Therapeutic regimens traditionally involve a combination of antifungal and antimicrobial agents, including amphotericin B, azoles, azithromycin, and miltefosine. Although amphotericin B is considered the gold standard due to its potent amoebicidal activity at concentrations as low as 0.01 μg/ml, its poor solubility and high toxicity can cause significant adverse effects such as nephrotoxicity, hematologic complications, and systemic symptoms like headache, vomiting, and fever. Additionally, in vitro studies have shown that N. fowleri may develop resistance to miltefosine at concentrations up to 40 μg/ml. This review underscores the critical need for early and accurate diagnostic tools, safer and more effective therapeutic alternatives, and greater public awareness to prevent exposure and improve patient survival. Further research is urgently required to develop novel treatment options and reduce the devastating impact of this neglected but deadly pathogen.

The growing global population has amplified the demand for food, making the international trade of livestock a significant threat to animal and public health due to the increased risk of zoonotic disease transmission through animal movement or the consumption of their products. Biosecurity measures (BSMs) and vaccination are two essential tools that, when effectively implemented, can significantly reduce the spread of diseases from livestock. However, their failure not only escalates the burden of disease but also compromises food security and public health. Weak or poorly enforced BSMs can undermine the efficacy of vaccinations, creating challenges against disease prevention efforts. Conversely, robust BSMs such as nutritional and environmental management, routine monitoring of disease, farm management, and hygiene provide a critical foundation for successful vaccination programs by minimizing disease exposure and ensuring vaccine effectiveness. Inappropriate vaccination administration, inadequate cold chain management, and the frequency of immunosuppressive illnesses are also reported as contributing factors to vaccine failure. This review delves into the interconnected roles of BSMs and vaccination, unveiling the importance of the implementation of biosecurity principles in preventing vaccine failure. It also explores how the integration of biosecurity practices and vaccination strengthens animal health systems, mitigates zoonotic risks, and enhances overall food safety. Future research should concentrate on integrated biosecurity techniques by strengthening on-farm biosecurity protocols, proper handling and administration of vaccines, careful disease surveillance, and awareness programs thereby increasing the resilience of our livestock industry against notable diseases.