100 years ago: New cure for Malaria

1. At a Glance

• The article is The Hindu's "100 years ago" column, dated 23 Sept 1926 (Berlin). It reports Plasmochin, a synthetic antimalarial, presented at the Scientists' and Doctors' Congress, Duesseldorf. It was claimed to be more effective than quinine [1].
• Plasmochin is also known as pamaquine. It is an 8-aminoquinoline identified in Germany in the 1920s through an early animal "high-throughput screen" in canaries infected with P. relictum [3].
• Pamaquine was the more toxic forerunner of primaquine. Primaquine is licensed to eliminate P. vivax and P. ovale hypnozoites [3][4].
• UPSC relevance: history of science, malaria elimination (India targets zero indigenous cases by 2030), and drug toxicity and radical cure [2][6].

2. Why in the News

• The trigger is the newspaper's centenary column. It is not a policy event, so it is a historical hook. [1]
• Current linkage: India left WHO's High Burden to High Impact (HBHI) group in 2024 [2].

3. Background & Evolution

• 1926: Plasmochin was presented at Duesseldorf. Early experiments were by "Professor Shell" on patients deliberately infected with malaria. The article says it was then tested by "Professor Muchlens" of the Hamburg Tropical Institute on over 100 malaria patients from various parts of the world. [1]
• The article's spellings are as printed; the names likely refer to Schulemann and Mühlens, but that is not confirmed by the sources.

• The article says "in many cases permanent cure is believed to have been effected". This was a claim, not established fact. [1]

• 1920s: Pamaquine was identified in Germany through screening in canaries. [3]

• 1941-45: The US antimalarial programme worked to improve pamaquine's profile, which led to primaquine. [3]
• 1952: FDA licensed primaquine. [3]
• Indian programme: The National Framework for Malaria Elimination (NFME) 2016-2030 was launched in February 2016. The National Strategic Plan (NSP) 2017-22 followed in July 2017, and NSP 2023-27 after that. [2]

4. Core Static Facts

Item	Fact
Plasmochin synonyms	Pamaquine, plasmoquine, plasmocide, rhodoquine, praequine [3]
Drug class	8-aminoquinoline [3]
Successor	Primaquine (less toxic) [3]
Primaquine role	Only licensed drug to eliminate P. vivax and P. ovale hypnozoites [3][4]
Comparator in 1926	Quinine [1]
India NFME	2016-2030 [2]
India goals	Malaria-free by 2027 (vision), elimination by 2030 [2]
India case data	Cases fell from 11,69,261 (2015) to 2,27,564 (2023). Deaths fell from 384 to 83. [2]
Vector control	Indoor Residual Spraying (IRS) and Long-Lasting Insecticidal Nets (LLINs), under Integrated Vector Management [2]

5. Multi-Dimensional Analysis

Scientific / Technological

• Plasmochin was an early synthetic alternative to plant-derived quinine, produced by systematic screening. [1][3]
• Toxicity limited pamaquine, which drove the search for safer 8-aminoquinolines. [3]
• Primaquine's radical cure of relapsing malaria acts on hepatic hypnozoites. [4]

Ethical / Governance

• The article notes experiments on "lunatics" deliberately infected with malaria. This is unethical by modern research standards, which require informed consent. [1]
• Modern safety concerns include haemolysis risk with 8-aminoquinolines. [5]

Historical

• The claim of "permanent cure" was optimistic. The drug was later superseded because of toxicity. [3]

Administrative

• India's approach uses "test, treat, track" surveillance and the Integrated Health Information Platform (IHIP). [2]
• Key tools are IRS and LLINs. [2]

Social / Health

• Malaria reduction is tied to the HBHI exit and to the 2030 elimination target. [2]

6. Recent Developments (last 12-18 months)

• WHO's World Malaria Report 2024 cited India's roughly 80% fall in cases and deaths over 2015-2023. [2]
• The 2025 World Malaria Day theme for India was "Towards a Malaria-Free India". [6]
• I found no sourced developments from 2026 in the search results.

7. Prelims Hooks

• Plasmochin is the synthetic antimalarial reported in 1926; its other name is pamaquine. [1][3]
• Pamaquine is an 8-aminoquinoline. [3]
• Primaquine descends from pamaquine and was FDA-licensed in 1952. [3]
• Primaquine kills P. vivax and P. ovale hypnozoites. [3][4]
• Quinine was the older standard against which Plasmochin was compared. [1]
• India's National Framework for Malaria Elimination covers 2016-2030. [2]
• NSP 2017-22 was launched in July 2017. [2]
• India exited the HBHI group in 2024. [2]
• Indian malaria cases fell from 11,69,261 (2015) to 2,27,564 (2023). [2]
• Indian malaria deaths fell from 384 to 83 over 2015-2023. [2]
• Core vector-control tools are IRS and LLINs. [2]

8. The Same Safety Problem from 1926 Is Still Not Fixed

• The reason Plasmochin failed is the reason its successor is still hard to use
• Pamaquine was dropped mainly because it was too poisonous, and primaquine was built to be safer [3].

• But primaquine still belongs to the same drug family, the 8-aminoquinolines, and still carries the same core danger: it can break red blood cells [5].

• Who it breaks them in: people with G6PD deficiency

• G6PD deficiency is an inherited condition where red blood cells lack an enzyme that protects them from stress.
• In such patients primaquine can cause acute haemolytic anaemia — red cells burst faster than the body can replace them [9].

• So WHO says patients should be tested for G6PD deficiency before primaquine is prescribed [9].

• Why that advice is hard to follow in a field clinic

• The test needs either a laboratory or a G6PD rapid diagnostic test (RDT) at the point of care; WHO had to publish a separate guide just on how to use these RDTs [10].
• A village health worker who has a malaria RDT in hand usually does not have a G6PD RDT beside it.

• Without the test the health worker has two bad choices: give primaquine and risk harm, or skip it and leave the sleeping liver parasites (hypnozoites) alive [4][9].

• The 14-day course is the second break point

• For radical cure WHO's regimen is primaquine daily for 14 days [9].
• The patient's fever goes away in 2-3 days, because the blood-stage drug works fast. The remaining 11 days feel pointless to the patient.
• Treatment is usually unsupervised, so many patients stop early. A part-finished course does not clear the hypnozoites, and the malaria comes back months later [9].

9. Why India's Malaria Numbers Look Better Than the Real Burden

• Two different numbers are in circulation, and they are not the same thing
• Reported cases are the ones that reached a government health facility and got entered into the system — 2,27,564 in 2023 [2].
• Estimated cases are what WHO calculates after adjusting the reported figure for how many cases never got reported, how many fevers were never tested, and how many people never went to a public facility [7].

• India's estimated burden for 2023 is about 2 million — roughly nine times the reported figure [2].

• The gap is not a small rounding difference

• In 2022 India made up 65.3% of estimated malaria cases in the WHO South-East Asia region, but only 21.8% of reported cases (1,76,522 out of 8,08,683) [8].

• That means most Indian malaria cases are being counted by a model, not by a clinic register.

• Why this matters more for elimination than it did for control

• Under a control programme you only need the number to fall. Under elimination you must find and treat every single case, because one missed case can restart local transmission.
• A patient treated at an unregistered private clinic or a chemist shop is invisible to IHIP surveillance, gets no follow-up, and often gets no radical-cure course at all [2].
• So the same surveillance gap that flatters the statistics is also what can defeat the 2030 target [2].

10. The Honest Case That India's Progress Is Real

• The strongest argument against the criticism above is worth stating plainly
• The fall is visible in the estimated numbers too, not only the reported ones: estimated cases dropped from about 6.4 million (2017) to about 2 million (2023), and estimated deaths from about 11,100 to about 3,500 [2].
• Since estimates already correct for under-reporting, a fall in the estimate cannot be explained away as "we simply stopped counting" [7].

• WHO removed India from the HBHI group in 2024 after looking at sustained declines in the high-burden states, which is an outside check, not a self-assessment [2].

• What the criticism still gets right

• Estimates carry wide uncertainty, because they are built on assumptions about health-service use [7].
• Falling from 6.4 million to 2 million is a control success. Going from 2 million to zero is a different task, and it needs case-by-case detection that the current reporting gap shows is not yet in place [2][8].

11. What Would Actually Close the Radical-Cure Gap

• NVBDCP should place G6PD rapid tests wherever malaria rapid tests already go
• Today a fever case can be confirmed as malaria at the village level, but the safety test for the cure is available only higher up.
• WHO has issued a dedicated operational guide on using G6PD RDTs to support P. vivax radical cure — the tool and the instructions both exist already [10].

• Pairing the two tests is what turns "diagnosed" into "safely cured".

• Move towards shorter radical-cure courses where the evidence supports it

• The 14-day course fails mostly because patients stop when the fever stops [9].
• Tafenoquine is a single-dose 8-aminoquinoline for radical cure, which removes the adherence problem entirely — but it needs an even stricter G6PD test first, because a single dose cannot be stopped once swallowed [5].

• So the shorter regimen and the G6PD test are one package, not two separate reforms.

• Make private-sector malaria notification real, not only on paper

• Cases treated outside the public system do not enter IHIP, so no one follows up to check whether the patient completed radical cure [2].

• Until private clinics, labs and chemists routinely notify, the state cannot do the "track" part of test, treat, track [2].

• Judge the programme by relapse, not only by first infections

• A P. vivax patient who relapses after four months is counted as a fresh case, so a failed radical cure looks like new transmission.
• Reporting relapses separately would show whether the 14-day course is actually being finished, which the present count hides [4][9].

12. Anchors for Answers

• Data: India's reported malaria cases 2,27,564 (2023) against an estimated burden of about 2 million — a roughly nine-fold gap [2][7]
• Data: India was 65.3% of estimated but only 21.8% of reported malaria cases in WHO South-East Asia, 2022 [8]
• Data: Estimated Indian cases fell 6.4 million (2017) to 2 million (2023); estimated deaths 11,100 to 3,500 [2]
• Report: WHO, Testing for G6PD deficiency for safe use of primaquine in radical cure of P. vivax and P. ovale (2016) — test before you treat [9]
• Report: WHO, World Malaria Report 2024 — estimated figures adjust reported cases for reporting completeness and health-service use [7]
• Comparison: WHO's 14-day primaquine regimen versus single-dose tafenoquine — the adherence fix that raises the G6PD testing bar [5][9]
• Scheme: NFME 2016-2030 and NSP 2023-27, with IHIP-based test, treat, track surveillance [2]

13. Mains Relevance

• GS-III: Science and technology (developments and applications). GS-II: Health, and government policies and interventions. GS-I: Modern history (limited relevance).
• Plausible question stems:
• Trace the evolution of antimalarial drugs from quinine to 8-aminoquinolines, and discuss the challenges of radical cure.
• Assess India's progress towards malaria elimination by 2030 and the bottlenecks.
• Ethics of human experimentation in early medical research: lessons for modern regulation.

14. Related Topics to Study Next

• Plasmodium species (falciparum, vivax) and relapse biology: hypnozoites explain why vivax needs primaquine.
• G6PD deficiency: it is the key haemolysis safety issue for 8-aminoquinolines.
• Tafenoquine: a newer radical-cure option, linked to primaquine.
• NFME 2016-2030 and NSP 2023-27: the policy framework.
• HBHI approach and the WHO World Malaria Report: international benchmarking.
• Integrated Vector Management (IRS, LLINs): the main control tools.
• Research ethics: links to the experiments described in the 1926 article.

15. Common Errors / Trap Areas

• Plasmochin (pamaquine) is not primaquine. Primaquine is the later, less toxic successor. [3]
• Plasmochin was synthetic; quinine is plant-derived.
• India's target is elimination by 2030. "2027" is the vision or NSP-period target. [2]
• Do not equate the 1926 claim of "permanent cure" with established efficacy.
• Hypnozoite-targeting drugs (primaquine) differ from blood-stage schizonticides.