Vaccines and immunisation

Prelims and Mains

A vaccine whose development begins when an outbreak does arrives too late to stop it. The coalition exists to pay for candidates in advance, and India is a founding member of it.

• The Coalition for Epidemic Preparedness Innovations (CEPI), launched in 2017, funds vaccines against emerging epidemic threats so that candidates are ready before an outbreak.
• The Ind-CEPI Mission is India's arm of that effort, run by the Translational Health Science and Technology Institute (BRIC-THSTI) and the Biotechnology Industry Research Assistance Council (BIRAC).
• It delivered GEMCOVAC-19, India's first mRNA vaccine against COVID-19.
• Covishield, by contrast, is a viral vector vaccine and not an mRNA one.

Prelims and Mains

Cervical cancer is one of the few cancers with a single known cause, and human papillomavirus (HPV) is it. A dose given before exposure therefore prevents the cancer rather than treating it, which is the whole case for vaccinating girls at 14.

• HPV types 16 and 18 cause most cervical cancers.
• The World Health Organization (WHO) accepted in 2022 that one dose protects girls of this age about as well as two, which makes a one visit campaign workable.
• The campaign was launched in February 2026 and offers a single free and voluntary dose at government health facilities.
• More than 80 lakh doses had been given by 11 September 2026, seven months after it was launched.
• About 1.2 crore girls turn 14 each year, which is the cohort the campaign has to reach.
• Coverage is tracked district by district on U-WIN.

Prelims and Mains

Streptococcus pneumoniae causes pneumonia, meningitis and sepsis when immunity weakens, and it wears a sugary coat, the capsular polysaccharide, that differs from one serotype to the next. Every vaccine in use aims at that coat, so it protects only against the serotypes it includes. The ones left out, many of them carrying antibiotic resistance genes, then fill the space, which is serotype replacement.

• British scientists reported ZPY-CpG-Ch on 3 September 2026, a protein based candidate found by reverse vaccinology.
• It carries three surface proteins shared across serotypes, so it does not depend on the capsule at all.
• Synthetic DNA (CpG) and chitosan are its adjuvants.
• 80 to 100 per cent of mice survived lethal serotype 1, comparable to PCV13, but only four serotypes were tested.
• It did not clear bacteria from the upper airways, so infection could still spread.

Prelims and Mains

Qdenga (TAK-003), made by Takeda of Japan, is a live attenuated tetravalent vaccine built on a dengue type 2 backbone using recombinant DNA technology. It is given as two doses under the skin three months apart, to people aged 4 to 60, and needs no test for earlier infection. Dengue has four serotypes, and antibodies from a first infection can help a different serotype enter cells in a second, which is called antibody dependent enhancement and is why dengue vaccines are hard to design.