Two types of new generation typhoid vaccines are available which are considered safe and efficient in controlling typhoid disease. These vaccines have replaced the old and not so safe inactivated whole-cell vaccine.
- Injectable Vi polysaccharide vaccine is a subunit vaccine, first licensed in the United States in 1994. It contains purified Vi capsular polysaccharide from the Ty2 S. Typhi strain. It is injected intramuscularly. It is given as a single dose to children older than 2 years with subsequent shots at every 3 year interval or at least one booster dose after 3 years.
- Vi polysaccharide conjugate vaccine is a Vi capsular polysaccharide linked to a conjugate. Vi conjugate vaccine provides longer lasting immunity as it has the ability to stimulate specialized cells in the human body called T cells, which the Vi polysaccharide alone cannot do. Vi conjugate vaccines are the only vaccines advisable for kids below 2 years of age. Bharat Biotech is the pioneer in developing Typbar – TCV which is a Vi capsular polysaccharide linked to tetanus toxoid (conjugate) vaccine. It is WHO certified and can be administered to infants above 6 months of age.
Recommended Schedule (According to revised IAP schedule 2014):
- Single primary dose of Vi PS conjugate (Typbar-TCV) can be given at 9-12 months maintaining the minimum 4 weeks gap with the MMR1 dose
- Booster dose of either Vi-polysaccharide (Vi-PS) or the conjugate vaccine can be given at 2 years of age if primary vaccination is done with conjugate vaccine
- Re-vaccination is not required if conjugate vaccine booster is given, as opposed to Vi-PS vaccine which require repeat doses every 3 years to ensure protection from Typhoid
Vaccination is advised for :
- Infants and young school going children
- microbiology lab technicians who handles pathogens
When should these vaccines be avoided?
In case of severe hypersensitive reaction to the first dose of this vaccine one should not get another dose.
Marketed Typhoid Products
Here is the list of WHO pre-qualified vaccine products available in market. Click on name of the product to know more.