About the disease
Brucellosis, also called Undulant Fever or Malta Fever, is one of the world's most common zoonoses. It causes a long, wavy fever that comes and goes, night sweats, joint pain, and severe fatigue. If untreated it becomes chronic and disabling — spondylitis, arthritis, or neurobrucellosis.
In animals it causes abortion in the last third of pregnancy, retained placenta, infertility, and reduced milk yield — a major economic burden on dairy farmers.
- Undulant fever (comes-and-goes over weeks)
- Drenching night sweats, headache
- Severe joint & back pain, muscle pain
- Weight loss, fatigue lasting months
- Enlarged liver / spleen (hepatosplenomegaly)
- Chronic: arthritis, spondylitis, orchitis, endocarditis, neurobrucellosis
Causative agent & transmission
Pathogen
Brucella species — Gram-negative, facultative intracellular, coccobacillary bacteria. Three main species matter in India:
- B. abortus — cattle & buffalo (most common)
- B. melitensis — sheep & goats (most virulent in humans)
- B. suis — pigs
Where the bacteria hide
In infected animals, Brucella lives in the uterus, udder and lymph nodes. Shed in huge numbers in placenta, foetal fluids, aborted foetuses and milk. Bacteria survive weeks in cool, moist environments — barn floors, wet manure, water troughs.
How humans get infected
- Drinking unpasteurised / raw milk and unripened cheese
- Handling aborted material without gloves
- Contact with birth fluids, placenta at calving
- Aerosol in barns, abattoirs, laboratories
- Cuts on skin, mucous membrane contact
Who is at highest risk
- Dairy farmers & herders
- Veterinarians & AI technicians
- Slaughterhouse & abattoir workers
- Brucella diagnostic-lab staff
- Raw-milk & soft-cheese consumers
What is happening right now
Under NIVEDI Phase V seromonitoring, RBPT-positive samples from Erode dairy cooperatives rose from 3.1 % → 7.8 % over 14 days. Confirmatory ELISA and PCR at ICAR-NIVEDI, Bengaluru. Nine human undulant-fever cases were reported to Erode PHC network in the same fortnight. The IDSP unit has traced 87 % of exposed contacts.
Under the National Brucellosis Control Programme (NADCP), S19 mass vaccination of eligible female calves (4–8 months) is being scaled up in Erode, Salem, and Namakkal. Test-and-cull operations at 4 index farms.
Red zones — where extra caution is needed
Rising sero-positivity, active human clusters. Free vaccination camps for calves; free RBPT screening for dairy workers at PHCs.
Dairy-belt districts. Increased occupational screening for veterinarians & AI workers. Farmers should vaccinate all female calves 4–8 months old.
Buffalo dairy belt. High risk. Mass vaccination camps at Medak & Rangareddy cooperatives under NADCP.
Peri-urban dairy — vigilance for imported carrier animals from other states. Report abortions to Bharat Pashudhan.
Step-by-step precautions
Drawn from the WHO Brucellosis Fact Sheet, WOAH Terrestrial Manual and India's DAHD National Brucellosis Control Programme (NADCP). Every step below cites the source it is drawn from.
Pasteurise milk before consumption — and for cheese, curd and other derivatives
WHOWHO's central preventive recommendation is "pasteurization of milk for direct consumption and for creating derivatives such as cheese". In Indian households where pasteurised milk isn't available, boil raw milk to a rolling boil before use. Never consume raw-milk cheese, chhena or khoa from unknown sources.
Vaccinate cattle, goats and sheep in endemic areas — S19 for female calves
WHO DAHD-NADCPWHO recommends "vaccination of cattle, goats and sheep is recommended in enzootic areas." India's National Animal Disease Control Programme (NADCP) delivers a single dose of Brucella S19 to female cattle & buffalo calves aged 4–8 months, free of charge at your Veterinary Assistant Surgeon's office. Do not vaccinate pregnant animals.
Use physical protection when handling animals
WHOWHO's guidance for farmers and butchers is to use physical barriers — gloves, overalls, aprons and eye protection — during any procedure that could bring skin or mucosa into contact with animal fluids. Cover cuts with waterproof plaster before entering the barn.
Correct handling and disposal of afterbirths, aborted foetuses and carcasses
WHO DAHDWHO calls for "correct handling and disposal of afterbirths, animal carcasses and internal organs". India's DAHD guidance adds: report all abortions in cattle or buffalo within 24 hours to the District Animal Husbandry Officer or Bharat Pashudhan FIR. Do NOT touch or bury without gloves. Bury deep or incinerate — never feed to dogs.
Minimise contact with blood, placenta, foetuses and uterine secretions
WHOWHO's occupational-safety guidance for veterinarians, AI technicians and abattoir workers: minimise contact "with blood, placenta, foetuses and uterine secretions". Aborting animals should be moved to a separate pen with its own feed and water; the previous location disinfected with 2 % phenol or 5 % bleach.
Lab safety and worker screening — RBPT for dairy workers
WHO NCDCWHO calls for appropriate laboratory safety measures for Brucella diagnostic labs. Under NCDC Zoonotic Disease guidance, dairy farm workers, veterinarians, AI technicians and abattoir staff in high-burden districts should receive free RBPT screening at their PHC. Early treatment with doxycycline + rifampicin prevents chronic disability.
Undulant fever with joint pain? Mention livestock or raw-milk contact
NCDCAny fever that comes and goes over more than two weeks, with heavy sweating and joint pain — see a doctor and clearly mention livestock contact or raw-milk consumption. Ask for an RBPT / ELISA test — the standard fever workup will miss brucellosis.