Science & Technology
New Brucellosis Vaccine by ICAR
- 24 Sep 2020
- 4 min read
Why in News
“Brucella abortus S19Δ per vaccine” is developed by the Indian Council of Agricultural Research’s -Indian Veterinary Research Institute (ICAR-IVRI) for brucellosis prevention in the dairy sector.
Key Points
- Brucellosis: It is a bacterial disease caused by various Brucella species, which mainly infect cattle, swine, goats, sheep and dogs.
- It is also known as Malta fever or Mediterranean fever.
- Brucellosis is a zoonotic disease and endemic in India causing huge economic losses to dairy industry due to:
- Infertility
- Abortion
- Birth of weak off springs
- Reduced productivity
- Old Vaccine:
- B. abortus S19 strain: In India, calf-hood vaccination is practiced using live attenuated Brucella abortus S19 strain for control of the disease.
- B. abortus S19 strain is a very strong immunogen and provides lifelong immunity.
- An immunogen refers to a molecule that is capable of eliciting an immune response by an organism's immune system.
- Drawbacks:
- Residual virulence to humans and animals.
- Not suitable for vaccination in adult animals.
- Causes abortion when used in pregnant animals.
- Interferes with sero-diagnosis of clinical infection.
- New Vaccine: To overcome some of these drawbacks, a modified strain of B. abortus S19 has been developed at ICAR-IVRI. The newly developed strain is named as B. abortus S19Δ per.
- It is developed under the Department of Biotechnology (DBT) funded “Brucellosis network program”.
- The programme aims at studying the epidemiological status of Brucella infections in India and to develop novel diagnostics and vaccines.
- In the process of modifying the S19 strain, lipopolysaccharide (LPS) structure of the organism was altered through deletion mutation.
- Lipopolysaccharide is the major component of the outer membrane of Gram-negative bacteria.
- A deletion mutation occurs when part of a DNA molecule is not copied during DNA replication.
- Vaccine potential of S19Δ per has been evaluated in experimental small animal models and also in buffalo calves.
- The vaccine has great demand in India and will be of immense help in the national control programme on brucellosis.
- The vaccine has DIVA capability.
- DIVA means differentiating infected from vaccinated animals. These vaccines, also termed as marker vaccines, can differentiate between naturally infected and vaccinated animals.
- It is developed under the Department of Biotechnology (DBT) funded “Brucellosis network program”.
Infection to Humans
- Brucellosis has infected over 3000 people in China.
- Humans generally acquire the disease through:
- Direct contact with infected animals or
- Eating, drinking contaminated animal products, unpasteurized milk or
- Inhaling airborne agents.
- The US Centers for Disease Control and Prevention states that person-to-person transmission of brucellosis is “extremely rare” but some symptoms may reoccur or never go away.
- Symptoms of Brucellosis include fever, sweats, malaise, anorexia (psychological disorder in which one eats less due to fear of weight gain), headache and muscle pain.
- Treatment and prevention:
- It is usually treated with antibiotics, including rifampin and doxycycline.
- Avoiding unpasteurised dairy products and taking safety precautions such as wearing rubber gloves, gowns or aprons, when handling animals or working in a laboratory can help prevent or reduce the risk of getting brucellosis.
- Other preventive measures include cooking meat properly, vaccinating domestic animals, etc.