Lumpy Skin Disease in India: Diagnostic Challenges, Differential Diagnoses, and Laboratory Confirmation 

Lumpy Skin Disease (LSD) is a contagious viral disease of cattle caused by Lumpy Skin Disease Virus (LSDV), a Capripoxvirus of the Poxviridae family. It has emerged as a major animal health concern in India due to its rapid spread, production losses, and control challenges, making accurate and timely diagnosis essential for effective disease management. 

The livestock sector plays a critical role in India’s economy, with the cattle population exceeding 300 million. During the major LSD outbreak in 2022, India experienced an estimated economic loss of USD 2217.26 million, largely due to cattle mortality, decline in milk production, abortion, infertility, and damage to hides¹.  

These substantial losses highlight the importance of early and accurate diagnosis. Molecular detection and seroprevalence studies provide essential insights into disease circulation and assist in selecting appropriate clinical samples for reliable diagnosis. 

Clinical Suspicion and Need for Laboratory Confirmation 

Clinical diagnosis of LSD is based on signs such as fever, lymphadenopathy, and skin nodules; however, these signs overlap with other diseases, creating diagnostic challenges. Laboratory confirmation is essential to distinguish LSD from other conditions. In a study among Vechur cattle in Kerala, two heifers with fever and skin nodules were confirmed positive for LSDV using PCR targeting the P32 gene, producing specific amplicons of 192 bp, validating clinical suspicion with laboratory evidence².  

Molecular Diagnosis Using PCR 

Polymerase Chain Reaction (PCR) is widely used for the diagnosis of Lumpy Skin Disease Virus (LSDV). During outbreaks in Meghalaya, real-time PCR targeting the LSDV126 genomic region detected viral DNA in 42 out of 56 clinical samples, confirming LSDV infection and demonstrating high diagnostic sensitivity. This assay also aided in differentiating LSD from other clinically similar pathogens³.  

In Madhya Pradesh and Telangana, conventional PCR targeting the P32 gene and the fusion gene detected LSDV in clinical samples, with tissue samples showing the highest positivity. Simultaneously, seroprevalence was assessed using indirect ELISA, revealing exposure rates in cattle populations¹. 

In Karnataka, molecular surveys with PCR showed 83.6% positivity in scabs, 80.9% in nasal swabs, and 76.9% in blood, underlining the utility of multiple sample types in diagnostics⁴.  

Sample Types and Diagnostic Yield 

Different sample types influence diagnostic yield. In a study of LSDV from cattle in Andhra Pradesh, PCR testing showed 88.24% (30/34) positivity in skin scabs and 17.65% (3/17) positivity in nasal swabs when amplifying the p32 and A33R genes, supporting molecular confirmation from accessible clinical specimens⁵.  

In Madhya Pradesh and Telangana, tissue samples showed 69.23% positivity for the P32 gene, while nasal swabs had lower positivity in PCR assays, reflecting higher reliability of tissue samples for detection¹.  

Differential Diagnosis Challenges 

Accurate diagnosis must differentiate LSD from other conditions with similar clinical presentations. Diseases such as pseudo-lumpy skin disease, bovine papular stomatitis, pseudocowpox, and dermatophilosis can present with nodular or ulcerative lesions, making molecular confirmation essential to rule out these differential diagnoses⁶. 

Additional Laboratory Methods 

Beyond conventional and real-time PCR, other laboratory tools support LSD diagnosis: 

• Histopathology reveals characteristic skin lesion changes that support molecular findings. In Kerala, histopathology of nodules showed pyogranulomatous myositis and vasculitis alongside PCR confirmation². 

• Serological tests (ELISA) contribute to understanding exposure prevalence in cattle herds, supplementing molecular methods¹. 

 Summary of Diagnostic Challenges 

Accurate diagnosis of LSD in India involves: 

• Clinical suspicion is based on signs such as fever and nodules, which are not specific to LSD alone. 

• PCR (conventional and real-time) uses gene targets like P32, fusion gene, and LSDV126 for confirmatory diagnosis. 

• Use of multiple sample types (scabs, tissue, nasal swabs) to improve test sensitivity. 

• Differential diagnosis to rule out other nodular skin diseases. 

• Supplementary methods (histopathology, serology) support laboratory confirmation. 

This integrated approach helps address the diagnostic challenges and ensures accurate identification of LSD in field and laboratory settings. 

 References 

1. Gupta V, Pravalika A, Pandey MK, Mareddy V, Jain AK, Singh A, Nayak A, Tripathi S, Rajoriya S. Molecular Detection, Seroprevalence and Biochemical Analysis of Lumpy Skin Disease Virus. Viruses. 2025 Feb 20;17(3):293. 
2. Manoj RV, Tresamol PV, Preena P, Manoj M, Anoopraj R, Justin Davis K, Shyma VH, Vijayakumar K. Occurrence and molecular confirmation of Lumpy skin disease among Vechur cattle in Kerala. J. Vet. Anim. Sci. 2025;56(2):387-92. 
3. Das S, Srinivas K, Milton AA, Khan S, Wahlang L, Kylla H, Reddy GB, Patil SS, Lyngdoh EL, Devi PC, Ghatak S. Epidemiology of lumpy skin disease in Northeast India and a new method for rapid field diagnosis. AMB Express. 2025 May 30;15(1):85. 
4. Bayyappa MR, Uma CR, Bijalwan S, Tadakod S, Nagaraj S, Naragund M, Pabbineedi SM, Basavarajappa CK, Gulati BR. Molecular epidemiological and spatiotemporal analysis of lumpy skin disease outbreaks in cattle from Karnataka, India. Frontiers in Cellular and Infection Microbiology. 2025 Jun 24;15:1596973. 
5. Saikumar G, Ramani PRN, Supriya AR. Molecular detection and phylogenetic analysis of lumpy skin disease virus from clinically infected cattle of Andhra Pradesh. Indian J Anim Health. 2023;62(2):312–319. doi:10.36062/ijah.2023.04423. 
6. Modise BM, Settypalli TB, Kgotlele T, Xue D, Ntesang K, Kumile K, Naletoski I, Nyange JF, Thanda C, Macheng KN, Marobela-Raborokgwe C. First molecular characterization of poxviruses in cattle, sheep, and goats in Botswana. Virology Journal. 2021 Aug 14;18(1):167.