Vaccine Interference: Yellow Fever and Cholera Vaccines
Certain vaccines, when administered close together in time, can blunt each other's immune response instead of each producing an independent, adequate response. This phenomenon of vaccine interference is classically described between the Yellow Fever vaccine and the (older, whole-cell) Cholera vaccine.
Why Cholera Vaccine Interferes
- Public health/preventive medicine texts (e.g., Park's Textbook of PSM) note that if the Cholera vaccine is given within 3 weeks before or after the Yellow Fever vaccine, it can reduce the antibody response to the Yellow Fever vaccine.
- Because of this documented interference, international health regulations traditionally recommended spacing these two vaccines at least 3 weeks apart whenever both were required (e.g., for travelers to endemic regions).
Why the Other Options Are Incorrect
- Typhoid vaccine: No significant interference with the Yellow Fever vaccine is described; typhoid vaccination can be co-administered or spaced normally without loss of efficacy for either vaccine.
- Tetanus toxoid: A toxoid (inactivated toxin) vaccine that does not compete immunologically with the live attenuated Yellow Fever vaccine; no interference interval is required.
- Measles vaccine: Although also a live attenuated vaccine, measles vaccine is not classically cited as interfering with Yellow Fever vaccine; in practice, live vaccines like measles and yellow fever can be given together or spaced by the standard 4-week live-vaccine rule, but the specific "3-week interference" teaching point pertains to cholera vaccine, not measles.
Conclusion
Among the given options, the vaccine specifically known to interfere with the Yellow Fever vaccine if administered within 3 weeks is the Cholera vaccine, making Option 1 the correct answer.
Important Questions from Infectious Disease Control & Prevention
As per the Open Vial Policy, partially used multidose vials of which of the following vaccines can be used over more than one immunization session?
1. BCG vaccine
2. DPT vaccine
3. Hepatitis B vaccine
4. Measles vaccine
Select the correct answer using the code given below.
Consider the following statements regarding dengue virus :
1. It has four distinct serotypes.
2. Infection with any one serotype confers lifelong immunity for that virus serotype.
3. Secondary infection with dengue serotype 2 leads to severe form of dengue.
Which of the statements given above are correct?
Consider the following statements regarding dengue :
1. The mosquito becomes infective after an extrinsic incubation period of 8-10 days.
2. Once it becomes infective, the mosquito remains infective for life.
3. The genital tract of the mosquito does not get infected.
Which of the statements given above are correct?
Consider the following statements about Kyasanur Forest Disease (KFD) :
1. It is transmitted by ticks.
2. It was originally called 'pig disease' because of the association with dead pigs.
3. It was first recognized in Karnataka State.
How many of the statements given above are correct?
- In countries with low levels of measles transmission, what should be the appropriate age for starting immuni-zation with measles-containing vaccine (MCV)?
