Tuberculosis (TB) is a chronic inflammatory and zoonotic disease caused by Mycobacterium tuberculosis complex (MTBC) members, which affects various domestic animals, wildlife, and humans. Some wild animals serve as reservoir hosts in the transmission and epidemiology of the disease. Therefore, the monitoring and surveillance of both wild and domestic hosts are critical for prevention and control strategies. For TB diagnosis, the single intradermal tuberculin test or the single comparative intradermal tuberculin test, and the gamma-interferon test, which is regarded as an ancillary test, are used. Postmortem examination can identify granulomatous lesions compatible with a diagnosis of TB. In contrast, smears of the lesions can be stained for acid-fast bacilli, and samples of the affected organs can be subjected to histopathological analyses. Culture is the gold standard test for isolating mycobacterial bacilli because it has high sensitivity and specificity compared with other methods. Serology for antibody detection allows the testing of many samples simply, rapidly, and inexpensively, and the protocol can be standardized in different laboratories. Molecular biological analyses are also applicable to trace the epidemiology of the disease. In conclusion, reviewing the various techniques used in MTBC diagnosis can help establish guidelines for researchers when choosing a particular diagnostic method depending on the situation at hand, be it disease outbreaks in wildlife or for epidemiological studies. This is because a good understanding of various diagnostic techniques will aid in monitoring and managing emerging pandemic threats of infectious diseases from wildlife and also preventing the potential spread of zoonotic TB to livestock and humans. This review aimed to provide up-to-date information on different techniques used for diagnosing TB at the interfaces between wildlife, livestock, and humans.
Wild animals are considered reservoirs, contributing to the transmission of emerging zoonotic diseases such as tuberculosis (TB). A cross-sectional study was conducted by opportunistic sampling from fresh carcasses of free-ranging wild boar (n = 30), and free-ranging wild macaques (n = 42). Stained smears from these tissues were tested for acid-fast bacilli (AFB) with Ziehl-Neelsen staining. Mycobacterial culture was conducted using Lowenstein-Jensen media and Middlebrook 7H11 agar media. Polymerase chain reaction (PCR) was performed through the detection of the 16S rRNA gene, with multiple sets of primers for the detection of Mycobacterium tuberculosis complex (MTBC) and Mycobacterium avium complex (MAC). In wild boars, 30% (9/30; 95% Confidence Interval: 16.7-47.9%) of examined samples showed gross tuberculosis-like lesions (TBLLs). Multiple nodular lesions that were necrotic/miliary with cavitation were found in the submandibular lymph nodes, tonsils, lungs, kidney and liver, while single nodular lesions were found in the mediastinal lymph nodes, spleen and mesenteric lymph nodes. Conventional PCR on the submandibular lymphoid tissues of wild boar (nine samples with TBLLs and three non-TBLL samples) showed that 75% (9/12) were positive for Mycobacterium bovis (95% CI: 46.8-91.1), and 91% (CI: 64.6-98.5) were positive for Mycobacterium avium. For macaques, 33.3% (10/30) were positive for M. avium (95% CI: 19.2-51.2) but negative for MTBC.
Mites infestation and gastrointestinal parasites including coccidia are common problems reported in pets, petting farms and farmed practices. Sarcoptes sp. and Cheyletiella sp. could be a potential zoonosis from rabbits to human. Detection of mites and coccidia with their zoonotic potential in meat-farmed rabbits from three (3) commercial farms in Selangor were investigated. Tape impression, fur pluck, skin scraping and ear swab tests were used for mites detection and faecal samples was used for coccidia examination by using McMaster's technique and the identification of Eimeria spp. was further analysed by sporulation technique. The overall prevalence of mites and Eimeria spp. (oocysts) in rabbits were 51.85% ± 0.38 (standard deviation; S.D.) and 76.47% ± 0.42 respectively. Sarcoptes scabiei was the most frequent mite found (25.92% ± 0.44), followed by Cheyletiella parasitovorax and Psoroptes cuniculi. Nine Eimeria spp. were identified and the oocysts of E. perforans shows the highest prevalence (64.71% ± 3.97) followed by E. exigua, E. coecicola, E. magna, E. flavescens, E. irresidua, E. intestinalis, E. media and E. stiedai. There was a significant difference (p = 0.013) where large-scale farm has a higher prevalence of coccidia than small scale farms apparently due to the excessive stocking density as coccidia are easily transmitted among rabbits through ingestion of sporulated oocysts. In conclusion, mites and coccidia are commonly present in the commercial rabbit farms, thus control and preventive measures should be executed to reduce the incidence of parasites. The zoonotic mites Sarcoptes scabiei and Cheyletiella parasitovorax detected in this study could be regarded as a public health concern especially when handling the rabbit.
Tuberculosis (TB) is a chronic inflammatory and zoonotic disease caused by Mycobacterium tuberculosis complex (MTBC) members, affecting several domestic animals, wildlife species and humans. The preliminary investigation was aimed to detect antibody against MTBC among indigenous wildlife which are free-ranged wild boar, free-ranged wild macaques and captive Asian elephants in selected areas of Selangor and elephant conservation centre in Pahang, respectively. The results indicate that MTBC serodetection rate in wild boar was 16.7% (7.3-33.5 at 95% confidence interval (CI)) using an in-house ELISA bPPD IgG and 10% (3.5-25.6 at 95% CI) by DPP®VetTB assay, while the wild macaques and Asian elephant were seronegative. The univariate analysis indicates no statistically significant difference in risk factors for sex and age of wild boar but there was a significant positive correlation (P<0.05) between bovine TB in dairy cattle and wild boar seropositivity in the Sepang district.