Brucellosis in migratory sheep flock from Maharashtra, India

Serological and molecular prevalence of Brucella spp. among livestock species in Rajasthan, India

A seroprevalence and molecular study was carried out in six districts of the state of Rajasthan, India to detect brucellosis in major livestock species. This study involves the testing of 3,245 livestock samples using the Rose Bengal Plate Test (RBPT), Indirect Enzyme-Linked Immunosorbent Assay (i-ELISA), and genus-specific polymerase chain reaction (PCR) markers for molecular diagnosis of the disease. In the tested samples, seroprevalence was 5.06% (CI: 1.96-8.15) using the RBPT test and 6.88% (CI: 1.98-11.78) using the i-ELISA test, while the cumulative seroprevalence (RBPT and i-ELISA) was 3.63% (CI: 0.44-6.83). The prevalence of the disease was 1.27% (CI: 0.56-3.11) when tested using molecular markers. The highest prevalence of brucellosis was detected in Cattle (7.00, 3.22%), followed by camels (5.50, 2.50%), buffalo (2.66, 0.00%), sheep (2.43, 0.41%), and goats (0.58, 0.23%) when serological (cumulative) and molecular diagnosis were considered preferred methods of detection. Cattle (3.22%) and camels (2.50%) also showed a high prevalence of disease when tested using molecular markers. The results of this study reveal that cattle, camel, and sheep brucellosis is prevalent in the study areas.

Journey towards National Institute of One Health in India

Background & objectives

Issues such as emerging and re-emerging infectious diseases, antimicrobial resistance, food security, biosafety and biosecurity are associated with changes in land use, population growth, urbanization, global travel and trade and climate change. As a result, a trans-disciplinary approach among human, animal and environmental health disciplines gained support. The Indian Council of Medical Research (ICMR) and Indian Council of Agricultural Research (ICAR) decided to establish a National Institute of One Health at Nagpur, Maharashtra, India. In this context, two collaborative research projects, funded by the ICAR and ICMR were initiated to conduct the epidemiological surveillance of selected zoonotic diseases in Central India.

Methods

Disease surveillance and molecular detection employing standard techniques like enzyme linked immunosorbent assay (ELISA), immuno-fluroscent assay (IFA), standard tube agglutination test (STAT) , Rose Bengal plate test (RBPT) and polymerase chain reaction (PCR) were undertaken based on the disease to be screened.

Results

In animals, the seropositivities for listeriosis (7.66%) and brucellosis (11.69%) were recorded. The occurrence of tuberculosis (3.8%) and leptospirosis (6.33%) was detected by PCR. Through cross-sectional studies from suspected human population with associated risk factors for zoonotic diseases, the seropositivity of brucellosis (1.83-11%), listeriosis (1.01-10.18 %), leptospirosis (8.14-12.67%) and scrub typhus (1.78-20.34%) was recorded. The investigations on scrub typhus indicated bimodal pattern during the months of pre-monsoon and post-monsoon season with a peak in post-monsoon in human cases. Ornithonyssus bacoti mites were identified from the rodents as a vector harbouring Orientia tsutsugamushi. The bovine tuberculosis was detected in 1.43 per cent human cases employing molecular assay.

Interpretation & conclusions

The data indicated the occurrence of important zoonotic diseases adversely affecting the livestock health and human wellbeing. The scientific collaboration between veterinary and medical faculties has set an example for effective implementation of One Health (OH) programme for the establishment of National Institute of OH.

Spatial sero-prevalence of brucellosis in small ruminants of India: Nationwide cross-sectional study for the year 2017-2018

Brucellosis in small ruminants caused mainly due to Brucella melitensis is an important zoonotic disease characterized by abortion, retained placenta, infertility, orchitis, epididymitis and rarely arthritis. Small ruminants are the main source of economy for the rural and marginally poor farmers and brucellosis is resulting in huge economic losses due to abortions and infertility and causing public health concern among the small ruminant keepers. Bovine brucellosis control programme has been implemented in India and small ruminants are left out of the programme mainly due to paucity of brucellosis status. The present cross-sectional study based on stratified random sampling was undertaken during 2017-18 to provide the nationwide brucellosis sero-prevalence in small ruminants. A total of 24,056 small ruminant serum samples (sheep samples = 8,103 [male-2,440 and female-5,663] and goat samples = 15,953 [male-4,331 and female-11,622]) sourced from 27 out of 29 states and two out of seven union territories (UTs), 350 districts of total 640 districts (54.68% of the Indian districts) and from 1,462 villages out of 6,40,867 villages (43.83% of the Indian villages). The serum samples were tested by indirect ELISA and overall brucellosis apparent and true prevalence of 7.45 (95% CI: 7.13-7.79) and 3.79 (95% CI: 3.44-4.17) was recorded. Significantly higher brucellosis sero-prevalence (p < .0001) was observed in sheep (11.55%) than goats (5.37%). Similarly, brucellosis seropositivity was highly significant in females compared to males in both sheep and goats. Countrywide, greater than 5% brucellosis sero-prevalence in sheep and goats was recorded in 14 and 10 states, respectively, indicating endemicity of the disease. The study provided the latest update on nationwide spatial sero-prevalence of small ruminant brucellosis which will aid government to strengthen regular surveillance and vaccination to reduce the disease burden and public health problems in the country.

A comparative study of serology and PCR for the diagnosis of brucellosis in goats

Brucellosis is an economically important infectious disease of livestock causing abortions, infertility, delayed oestrus, interrupted lactation, increased condemnation and loss of milk production besides its zoonotic nature. The present study was conducted to compare serological assays and polymerase chain reaction (PCR) for the diagnosis of caprine brucellosis. A total of 301 whole blood samples to extract DNA for PCR and serology were collected from goats maintained at various organized herds, panjarapoles, slaughter house, local meat markets, etc. in South Gujarat region of India. Out of 301 serum samples tested, 7 samples (2.33%) were positive by all the three serological tests, viz. rose bengal plate test (RBPT), indirect ELISA (iELISA) and immunochromatographic assay (ICA). Among 301 DNA samples, genus specific PCR detected DNA of Brucella spp. in 11 samples by targeting BCSP 31 and IS-711 genes to get 223 bp and 350 bp PCR products on agarose gel electrophoresis. None of the seven serologically positive samples showed Brucella genus-specific DNA amplification by PCR and similarly all PCR positive samples were negative on serology.

Risk factors for Brucella spp. and Coxiella burnetii infection among small ruminants in Eastern India

Small ruminants are the main reservoirs for brucellosis and coxiellosis, two zoonotic diseases affecting livestock production, and posing a public health threat in India. Understanding disease prevalence and risk factors associated with small ruminant infection can help mitigate disease transmission.

We report a cross-sectional survey in the states of Assam and Odisha in Eastern India. We interviewed 244 farmers to assess knowledge, attitude and practices relevant to brucellosis and coxiellosis infection. Serum samples from 411 goats and 21 sheep were analysed using enzyme-linked immunosorbent assay and Rose-Bengal Brucella agglutination plate test. Higher Brucella and Coxiella burnetii seroprevalence were found in Odisha (22% and 11.5%, respectively) than Assam (9.8% and 1.6%, respectively), and certain districts in Odisha were at higher risk. No association was found between seropositive animals and clinical signs, a challenge when attempting to identify seropositive animals in the herd. None of the farmers interviewed were aware of brucellosis, its aetiology, clinical form, or zoonotic risk. This study acts as a first indication of the extent of these diseases among small ruminants in these Indian states, highlighting how farming practices are associated with increased risk of infection. More research is urgently needed to mitigate zoonoses transmission in this region.

Imaging-Assisted Diagnosis and Characteristics of Suspected Spinal Brucellosis: A Retrospective Study of 72 Cases

Background

We clarified the imaging features of Brucella spondylitis to enhance our understanding of the disease and to minimize misdiagnosis.

Material/Methods

Imaging data (X-ray, computed tomography [CT], and magnetic resonance imaging [MRI] data) of 72 Brucella spondylitis patients treated from 2010 to 2017 were retrospectively analyzed; diagnoses was made by evaluating laboratory and pathological data.

Results

X-ray films revealed changes in intervertebral space heights, the number of lateral osteophytes, and bone destruction, which were more severe in the following order: lumbosacral vertebrae (56 cases, 77.8%), cervical spine (6 cases, 8.3%), thoracic spine (5 cases, 6.9%), and multi-segmental mixed vertebrae (5 cases, 6.9%). CT revealed osteolytic destruction attributable to early-stage Brucella spondylitis (endplate and vertebral lamellar osteolysis), usually associated with multiple vertebral involvement, with the middle and late disease stages being characterized by osteophytes in the vertebral margins and bony bridges, endplate sclerosis, and vertebral osteosynthesis. We encountered 54 cases (75%) with endplate lamellar osteolysis, 37 (51.4%) with vertebral lamellar osteolysis, 59 (81.9%) with marginal osteophytes, 10 (13.9%) with bony bridges, 25 (34.7%) with vertebral laminar sclerosis, and 17 (23.6%) with vertebral osteosynthesis. MRI revealed early, low-intensity, differential T1WI vertebral and intervertebral signals, with occasional iso-signals, T2WI iso-signals or high-intensity signals; and T2WI-FS vertebral and intervertebral high-intensity signals, commonly from vertebral soft tissues and rarely from paravertebral abscesses.

Conclusions

A better understanding of the X-ray, CT, and MRI features of Brucella spondylitis could aid in diagnosis when combined with epidemiological and laboratory data, thus minimizing misdiagnosis.