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Your Class 12 biology book explains vaccination in one paragraph: give the body a weakened or inactivated form of a pathogen, and it builds a memory that fights the real infection later. Behind that paragraph are people who took real risks to show it worked. One of them made his most important vaccine in Bombay, in a city gripped by plague. This post tells Waldemar Haffkine's story from official and peer-reviewed sources, explains the biology, works through how vaccine efficacy is calculated, and ends with what his way of working can teach you.
Who was Waldemar Haffkine?
The Haffkine Institute's own biography records that he was born on 15 March 1860 in Odessa, then in the Russian Empire, and died on 26 October 1930 in Lausanne, Switzerland. He entered the University of Odessa in 1879 to study physics, mathematics and zoology, and came under the influence of Elie Metchnikoff. In 1889 he moved to Paris to work in Louis Pasteur's laboratory.
There he worked on cholera. The Institute's page says he weakened the bacterium by exposing it to blasts of hot air, confirmed the effect in animals, and in July 1892 carried out the first human test on himself. A review in the Journal of Medical Biography by J. Hawgood adds that, from field trials in India between 1893 and 1896, he has been credited with the first effective preventive vaccination for a bacterial disease in humans.
What happened when plague reached Bombay?
Plague is caused by the bacterium Yersinia pestis and spreads mainly through the bites of infected fleas, according to the World Health Organization fact sheet. Untreated, bubonic plague kills 30% to 60% of those infected. In 1896 it broke out in Bombay, and the Governor invited Haffkine to the city.
The Institute's biography says he found space at the JJ Group of Hospitals and developed a plague vaccine there. On 10 January 1897 he had himself injected with 10 cc of the preparation, "thus proving in his own person the harmlessness of the fluid". The vaccine was tested on volunteers at Byculla jail the next month, and field use followed quickly. He described his preparation in the British Medical Journal that June in Remarks on the plague prophylactic fluid.
In 1898 the laboratory moved to a bungalow owned by Aga Khan III, and about half of Bombay's Khoja community, some 10,000 to 12,000 people, were inoculated under his sponsorship. In August 1899 Haffkine took over larger premises as Director of the Plague Research Laboratory. The Institute's milestones page dates the laboratory to 1899 and its renaming as the Haffkine Institute to 1925.
How does a vaccine like Haffkine's work?
The NCERT Class 12 chapter Human Health and Disease lists plague among bacterial diseases and explains that vaccination is "based on the property of 'memory' of the immune system". A preparation of antigenic proteins, or of inactivated or weakened pathogen, makes the body produce antibodies and memory B and T cells. On real exposure, the response is fast and large. Haffkine's cholera vaccine used a weakened organism; the same chapter explains this is active immunity, unlike passive immunity, where ready-made antibodies are injected.
Plague today is treated with antibiotics, and the WHO stresses that early diagnosis and treatment save lives. Health questions belong with a doctor; this post is about history and reasoning.
Worked example: how do you measure whether a vaccine works?
These are sample numbers for practice, not Haffkine's data. In a town, 2,000 people are vaccinated and 2,000 are not. During an outbreak, 12 vaccinated people and 60 unvaccinated people fall ill.
Attack rate, vaccinated. 12 ÷ 2,000 = 0.006, or 0.6%.
Attack rate, unvaccinated. 60 ÷ 2,000 = 0.030, or 3.0%.
Relative risk. 0.006 ÷ 0.030 = 0.2. A vaccinated person had one-fifth the risk.
Vaccine efficacy. 1 − 0.2 = 0.8, or 80%.
What mistakes do students make with these numbers?
Subtracting percentages. 3.0% − 0.6% = 2.4 percentage points is the absolute difference. Efficacy is the relative reduction, 80%. Both are useful; do not confuse them.
Comparing raw counts. If the groups differ in size, compare rates, not numbers of cases.
Ignoring how groups were chosen. If healthier people chose to be vaccinated, the vaccine looks better than it is. Fair comparisons need similar groups.
Mixing up active and passive immunity. A vaccine trains your own immune system; an antitoxin injection supplies ready-made antibodies.
For the immunology behind this, our guide to human health and immunity covers the chapter, and Edward Jenner's story shows where vaccination began.
What can a student take from how Haffkine worked?
Test where the problem is. He took his cholera and plague work to the places where people were dying.
Accept risk to yourself before others. He tested both vaccines on himself first.
Measure, then scale. Trials in a jail came before mass use.
Keep going after setbacks. The Mulkowal tragedy cost him years, yet his laboratory became one of India's lasting public health institutions.
A practice routine: redo the example with 30 cases in each group of 1,500, then explain in two sentences why that result would mean the vaccine did not work. If terms like antigen, memory cell and active immunity are still fuzzy, the Fermi Concept Library covers every concept in biology, so you can revise them before your next test.
Next step: read the vaccination section of the NCERT chapter and write the difference between active and passive immunity in your own words.
