An inexpensive and user-friendly laboratory test for the diagnosis of glanders in different animals has been developed by scientists.
Glanders, which is usually fatal to both animals and humans, is caused by the bacterium Burkholderia mallei.
It affects mainly horses, mules, and donkeys. Signs of infection include lung lesions and ulcers of mucous membranes in the respiratory tract. The acute form results in coughing and a fever, then blood poisoning, resulting in death within days. However, chronically infected horses can be symptom-free but may remain highly infectious.
The pathogen is considered a potential biological warfare or bioterrorism agent because of its high mortality rate and the small number of organisms needed to cause infection.
Ulrich Wernery and his fellow researchers, writing in the journal PLOS Neglected Tropical Diseases, said laboratory diagnosis of glanders can be difficult.
“The bacterium is often not readily isolated from clinical specimens due to its slow growth rate on standard culture media,” they said, “and may not be correctly identified based on its clinical features even when isolated.”
They noted that efforts have been made to develop serological tests for glanders, with the optimal test being one that can detect the antibody response.
The study team described their work to successfully develop such a test and assess its effectiveness.
They found that their test had high sensitivity (97.2%) and specificity (100%) for the detection of B. mallei antibodies in different animals.
“Such high sensitivity and specificity … make it a user-friendly and inexpensive assay for laboratory diagnosis of glanders for different animals in veterinary laboratories,” they concluded.
The study team comprised Wernery, Rekha Raghavan, Ginu Syriac and Marina Joseph, all with the Central Veterinary Research Laboratory in Dubai; and Elaine Chan, Jade Teng, Sing-Yung Siu, Man-Lung Yeung, Lilong Jia, Jian-Piao Cai, Tsz-Ho Chiu, Susanna Lau and Patrick Woo, all with the University of Hong Kong.
Their work was supported by the Research Fund of the Central Veterinary Research Laboratory and the Hong Kong Health and Medical Research Fund.
Wernery U, Chan E, Raghavan R, Teng JLL, Syriac G, Siu S-Y, et al. (2021) Development of a sensitive competitive enzyme-linked immunosorbent assay for serodiagnosis of Burkholderia mallei, a Tier 1 select agent. PLoS Negl Trop Dis 15(12): e0010007. https://doi.org/10.1371/journal.pntd.0010007