Evidence of Coxiella burnetii in Punjab province, Pakistan

• Published in: Acta tropica 2016-11, Vol.163, p.61-69
• Main Authors: Shabbir, Muhammad Zubair, Akram, Sidra, Hassan, Zia ul, Hanif, Kashif, Rabbani, Masood, Muhammad, Javed, Chaudhary, Muhammad Hamid, Abbas, Tariq, Ghori, Muhammad Taslim, Rashid, Haroon, Jamil, Tariq, Islam, Zia-ul, Rasool, Haisem, Bano, Asghari, Ahmad, Arfan, Ali, Muhammad Asad, Yaqub, Tahir, McVey, Walt, Jayarao, Bhushan M.
• Format: Article
• Language: English
• Subjects: Animals; Antibodies, Bacterial - immunology; Coxiella burnetii; Coxiella burnetii - genetics; Coxiella burnetii - isolation & purification; Cross-Sectional Studies; DNA, Bacterial - analysis; Enzyme-Linked Immunosorbent Assay - veterinary; Goat Diseases - epidemiology; Goats; IS1111 gene; Pakistan; Prevalence; Q Fever - epidemiology; Q Fever - veterinary; Real-Time Polymerase Chain Reaction; Risk factor analysis; Ruminants; Seroepidemiologic Studies; Sheep; Sheep Diseases - epidemiology; Small ruminants; Soil; Soil Microbiology
• ISSN: 0001-706X; 1873-6254
• DOI: 10.1016/j.actatropica.2016.07.017

[Display omitted] •Coxiella burnetii is prevalent in the environment (soil) and potential reservoirs (small ruminants) in Punjab province of Pakistan.•The prevalent strains are genetically distinct and their occurrence in soil have predisposition to some soil characteristics and risk factors.•Future studies are much essential to reveal further disease epidemiology and potential risk to direct-contact population, the farmers and veterinarians. Coxiella burnetii causes query (Q) fever, an important zoonotic disease with worldwide significance. The role of environment in the ecology of C. burnetti, and its influence on seroconversion in animals has not been elucidated in Pakistan. We carried out a cross-sectional study in Punjab province to (1) determine the prevalence and distribution of C. burnetii in soil using an ISIIII gene-based real time-polymerase chain reaction (RT-PCR) assay, (2) analyze association between the occurrence of C. burnetii in soil and its predictors i.e. soil characteristics (macro- and micro-nutrients) and several likely risk factors including the seroconversion in small ruminants at places where its genome had or had not been detected, and (3) predict homology and genetic diversity of the identified strains using sequences originated from different hosts worldwide. A total of 2425 soil samples from nine districts of Punjab province were processed. C. burnetii DNA was detected in 47 samples (1.94%, 95% CI: ±0.55) originating from 35 villages of studied districts (7.22%, 95% CI: ±2.30). The highest prevalence was found in Attock (7.11%, 95% CI: ±3.36), followed by Lahore (4.83%, 95% CI: ±3.49), Sahiwal (4.70%, 95% CI: ±2.6), Dera Ghazi Khan (2.33%, 95% CI: ±2.02), Faisalabad (1.35%, 95% CI: ±1.18) and Sheikhupura (0.68%, 95% CI: ±0.94). The odds of detecting bacterial DNA in soil was increased with a unit increase in organic matter [2.511 (95% CI: 1.453–4.340), p=0.001] and sodium [1.013 (95% CI: 1.005–1.022), p=0.001], whereas, calcium [0.984 (95% CI: 0.975–0.994), p=0.002] and potassium [0.994 (95% CI: 0.990–0.999), p=0.011] had protective effect where a unit increase in each analyte decreased odds for its occurrence by 1.0% approximately. Likewise, for categorical variables (risk factors), the odds of detecting C. burnetii were higher at locations >500m away from a main road [1.95 (95% CI: 1.06–3.78), p=0.04]. The enzyme-linked immunosorbent assay (ELISA) revealed an increased prevalence of antibodies in sheep (17.9%, 95% CI: ±5.54)