Scholarlink

<p>Advancing epidemiological insights is instrumental in optimizing region-specific hemopathogen control. A retrospective study in Chennai, South India screened 2,434 cattle over one year, revealing a 13.93% hospital-based prevalence of morphologically similar hemopathogen <i>(Babesia</i>,<i> Theileria</i>,<i> Anaplasma)</i> diseases (HPDs) by light microscopy (LM). Anaplasmosis predominated (8.63%), increasing during monsoon; theileriosis rose to 4.44%, babesiosis declined to 0.86%, with highest prevalence in multiparous Jersey crossbreds. Relative sensitivity, specificity, PPV and NPV of LM were prospectively estimated using PCR as an operational reference standard in cattle suspected of HPDs. Specific primers targeting <i>Babesia</i> (18&#xa0;S rRNA, 450&#xa0;bp), <i>T. annulata</i> (merozoite surface antigen, 721&#xa0;bp) and <i>A. marginale</i> (major surface protein, 265&#xa0;bp) were used. LM demonstrated a relative sensitivity of 73.08% and an NPV of 76.67%, reflecting under-detection of PCR-positives and false-negative classifications. Substantial LM–PCR agreement (κ = 0.72) with one-sided discordance supports a complementary LM-PCR diagnostic approach. Overlapping clinical profiles showed severe fever, lymph node, conjunctival and lacrimation changes in theileriosis, and jaundice in anaplasmosis; infected cattle had lymphocytosis, neutropenia, anemia, and elevated AST, ALP, BUN, SC. Conclusively, given the sustained prevalence of bovine prioplasmosis and anaplasmosis in Chennai, control should integrate periodic PCR screening of high-risk crossbred cattle (targeted surveillance) with pre-monsoon/monsoon acaricide and anti-piroplasmal/anti-rickettsial intensification (region-specific prophylaxis). This integrated approach detects LM-missed positives, distinguishes similar-looking hemopathogens, and facilitates pathogen-specific therapy (anti-babesial, anti-theilerial, anti-anaplasmal), with targeted clearance of carriers (notably <i>A. marginale</i>), reducing treatment failure, drug misuse and transmission surges. However, these hospital data may be biased by repeat cases, warranting field validation.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Microscopy-PCR discordance and shifting epidemiology in South India: advancing diagnostic precision for control of morphologically similar bovine hemopathogens (Babesia, Theileria, Anaplasma) from a hospital-based study

  • 期刊论文

  • 发表日期：

    2026年7月14日

查看全文
  • Vivek Joshi,
  • S. Kavitha,
  • K. Vijayarani,
  • C. S. Arunaman,
  • H. Vijayakumar,
  • N. R. Senthil,
  • A. Gopalakrishnan,
  • J. K. Chamuah

摘要

Advancing epidemiological insights is instrumental in optimizing region-specific hemopathogen control. A retrospective study in Chennai, South India screened 2,434 cattle over one year, revealing a 13.93% hospital-based prevalence of morphologically similar hemopathogen (Babesia, Theileria, Anaplasma) diseases (HPDs) by light microscopy (LM). Anaplasmosis predominated (8.63%), increasing during monsoon; theileriosis rose to 4.44%, babesiosis declined to 0.86%, with highest prevalence in multiparous Jersey crossbreds. Relative sensitivity, specificity, PPV and NPV of LM were prospectively estimated using PCR as an operational reference standard in cattle suspected of HPDs. Specific primers targeting Babesia (18 S rRNA, 450 bp), T. annulata (merozoite surface antigen, 721 bp) and A. marginale (major surface protein, 265 bp) were used. LM demonstrated a relative sensitivity of 73.08% and an NPV of 76.67%, reflecting under-detection of PCR-positives and false-negative classifications. Substantial LM–PCR agreement (κ = 0.72) with one-sided discordance supports a complementary LM-PCR diagnostic approach. Overlapping clinical profiles showed severe fever, lymph node, conjunctival and lacrimation changes in theileriosis, and jaundice in anaplasmosis; infected cattle had lymphocytosis, neutropenia, anemia, and elevated AST, ALP, BUN, SC. Conclusively, given the sustained prevalence of bovine prioplasmosis and anaplasmosis in Chennai, control should integrate periodic PCR screening of high-risk crossbred cattle (targeted surveillance) with pre-monsoon/monsoon acaricide and anti-piroplasmal/anti-rickettsial intensification (region-specific prophylaxis). This integrated approach detects LM-missed positives, distinguishes similar-looking hemopathogens, and facilitates pathogen-specific therapy (anti-babesial, anti-theilerial, anti-anaplasmal), with targeted clearance of carriers (notably A. marginale), reducing treatment failure, drug misuse and transmission surges. However, these hospital data may be biased by repeat cases, warranting field validation.