Vivotif: Typhoid Oral vaccine a traveller vaccine
Vivotif: Typhoid oral vaccine is given to prevent typhoid fever also known as enteric fever. This is Vivotif: Typhoid oral vaccine by Crucell Switzerland LTD. This is live attenuated vaccine. Live attenuated means these are live bacterium without causing diseases. In this vaccine Salmonella typhi ty21a strain is used. It is in both viable and non viable form.
How is Vivotif: Typhoid oral vaccine available?
Vivotif: Typhoid oral vaccine is available as capsule that is taken orally. It is available in enteric coated capsule. Usually comes in package of 4 capsules.
How is Vivotif: Typhoid oral vaccine stored?
Vivotif: Typhoid oral vaccine is stored at 2-8 degree Celsius. The temperature is maintained with the help of cold chain. The temperature range should be maintained at all stages of the storage and transportation. The vaccine if frozen accidentally should be discarded and should not be used. The vaccine if passed beyond expiry date should not be used and discarded.
How is Vivotif: Typhoid oral vaccine given?
This is given orally with water which is at temperature less than 98.2F. It should be given empty stomacj at least 1 hr before food. It is given in prescribed schedule and doses. The doses should not be exceeded.
At what age Vivotif: Typhoid oral vaccine is given?
This can be safely given to all above age 6 years and adults. It is currently not recommended to all in USA. It is to be taken who are planning to visit endemic countries for typhoid. The dosing schedule is one capsule on day 0, 2, 4, 6. The dosing should be completed at least 7 days before visit to endemic areas.
It is also suggested who have come in contact with typhoid carriers.
It is also suggested for those who are microbiology lab workers.
The booster is suggested to take after every 5 years in same dosages.
What if some has missed dose of Vivotif: Typhoid oral vaccine?
If someone has missed the dose of Vivotif: Typhoid oral vaccine should get it earliest as possible. The decision to take vaccine should be taken after consultation with pediatrician. Those children staying in endemic area like South east Asia and Indian subcontinent should get this vaccine or injectable Typbar tcv or Zyvac TCV vaccine which are comparatively more effective . Those planning to visit these regions or other endemic regions should get this vaccine at least 7 days before exposure.
How does Vivotif: Typhoid oral vaccine works?
This contains Live bacterium Salmonella typhi ty21a strain. When this vaccine is given orally to the host all these becterium are entered into the body. Inside the host these antigens are recognized by the immune system of the host. The immune mechanism to fight against these antigens is developed. When real infection occurs the immune response is rapidly ramped up and the disease is prevented. This is active form of immunization that is host himself/herself develops the immunity by its own mechanism after vaccination. The boosters are needed to maintain the long term immunity as after many years the immunity may wane. The tetanus toxoid in the vaccine acts as conjugation protein and it helps the immune system to recognize the antigens more effectively. Tetanus toxoid increases the efficacy of the vaccine. Yet the duration this vaccine provides protection is unknown, theoretically it seems it is efficient at least till 18 years of age.
Safety of Vivotif: Typhoid oral vaccine with other drugs:
As this is live attenuated vaccine it is safe to give the vaccine with most of the other medicines and other vaccine. It is safe if given with other vaccines like MMR, measles and pneumococcal vaccines.
The vaccine should not be given and postponed if patient is on oral antibiotics.
The vaccine if given with other vaccines should not be mixed in same syringe it should be given separately and at separate site.
The vaccine is not safe for immunocompromised patients and those with HIV AIDS stage 3 and stage 4 disease patients.
The safety of vaccine is not yet established in pregnancy and lactating mothers.
What are side effects after Vivotif: Typhoid oral vaccine?
This vaccine is S. typhi Vi-polysaccharide antigen conjugated to tetanus toxoid.
· Fever may come after the vaccination it may last for 3 days and usually mild to moderate grade. It can be easily controlled with paracetamol oral medicine and sponging. It can be managed at home.
· Abdominal pain may occur after vaccination. It is usually less. This pain can be managed with cyclopam.
· Irritability may come after vaccination may last for 1-3 days usually subsides by its own.
· Headache may occur after vaccination this side effect can be easily managed with paracetamol and usually subsides by its own.
· Lose motions and vomiting may occur in few patients after vaccination. It can be managed with Oral rehydrating solution and if needed medicine like ondansetron.
· If patient is allergic to any component anaphylaxis reaction may occur. This is extremely rare side effect but can be life threatening. The facility at which vaccination is given should be equipped with treatment to manage anaphylaxis reaction.
To whom Vivotif: Typhoid oral vaccine should not be given?
This vaccine should not be given to someone if known allergic to any of its components.
The contraindications Of this vaccine are very rare, advice of pediatrician should be considered before any conclusion.
Those on antibiotics should postpone this vaccine.
Those less than 6 years should not take this vaccine.
Those who are pregnant and lactating mothers should not take this vaccine as safety data of this vaccine is not yet established in this age group.
Those who have vomiting and lose motions should postpone this vaccine till they are fine.
Those with immunocompromised status and HIV AIDS should takes doctor’s advice before taking this vaccine.
Cautions needed to be taken
This vaccine has efficacy of 60-70 percent that implies it just reduces the risk of getting typhoid or enteric fever.
Those who have taken this vaccine may still get typhoid disease or enteric fever.
They should follow safety hygiene while eating and drinking and follow hand washing to avoid getting infected and the disease.