Vaccination and Immunity

These are delayed type hypersensitivity skin tests which are mediated by T-cells.

Clinical evaluation of infection incidence in the field post-completion of an immunization programme of susceptible individuals provides the most important evidence of efficacy. Such data may take 2 or 3 years to be collected, depending on the periodicity of infection with the organism. Long term immunity data is collected over 25 years to check that the provoked immunity is life-long (especially in these days of longer life spans).

DOTS-Plus is a World Health Organization-approved strategy for treating Multi-Drug Resistant Tuberculosis (MDR-TB). It stands for 'Directly Observed Treatment, Short-course' Plus, an enhanced version of the standard DOTS program specifically designed for TB cases that are resistant to standard first-line antibiotics. It is not for malaria, typhoid, or rabies.

Passive immunity is also provided through the transfer of IgA antibodies found in clostrum that are transferred to the gut of the infant, protecting against bacterial infections.

1

2

Interferons are indeed low molecular weight proteins produced by host cells in response to viral infection. They protect other cells by inducing an antiviral state, inhibiting viral replication, and activating immune cells. This is a key component of the innate immune system's defense against viruses. Hormones regulate physiological processes, antigens trigger immune responses, and phytotoxins are plant toxins.

Bananas have been developed that produce a human vaccine against hepatitis B.

Hepatitis-B vaccine is called sub-unit vaccine or second generation vaccine. 

Yes, this is the correct answer.

IgA immunoglobulin protects mucosal surfaces; prevents attachment of pathogens to epithelial cells.

Haffkine Institute in Mumbai is a premier biomedical research institute known for producing anti-snake venom (ASV) and other antitoxins. It has been a major supplier of ASV in India for decades. The Pasteur Institute in France works on vaccines but is not the primary ASV producer for India.

Smallpox vaccination uses weakened (attenuated) live virus - specifically the vaccinia virus, which is similar enough to smallpox to stimulate immunity but much safer. Killed germs would not produce effective immune memory. Live antibodies are not administered directly. Activated germs would cause disease rather than immunity.

The yellow fever vaccine was formulated in 1932. The vaccine was developed by Max Theiler and colleagues, leading to Theiler's Nobel Prize in 1951. The correct answer is A (1932), not the other years listed. This was a major breakthrough in tropical medicine.

These are the type of vaccines that are used for diptheria and tetanus. In this type of vaccine, the toxoids produced by the bacteria are made harmless. Toxoids are used to stimulate antibody production, but there is no risk of infection by the pathogen.