01 / 04
Humanity’s Most Ancient Enemy May Be on Its Way Out

Blog Post | Health & Medical Care

Humanity’s Most Ancient Enemy May Be on Its Way Out

Thanks to COVID-19, few have noted the emergence of an amazing new malaria vaccine.

Summary: Malaria, a deadly disease caused by parasites transmitted by mosquitoes, has plagued humanity for millennia. However, thanks to scientific and technological innovations, as well as global cooperation, malaria may soon be eradicated. This article explores the history, challenges, and prospects of eradicating humanity’s most ancient enemy.

Timothy C. Winegard’s The Mosquito: A Human History of Our Deadliest Predator contains many interesting tidbits. For example, the American historian argues that mosquitoes may have played a role in the extinction of dinosaurs. He also notes that the diseases mosquitos carry have been around long enough to alter human DNA (e.g., the prevalence of sickle cell disease among people of African ancestry). According to Winegard, the mosquito “has ruled the earth for 190 million years and has killed with unremitting potency” some 52 billion people (i.e., more than all wars in history combined).

One of the most interesting passages relates to the so-called “Darien Scheme,” which was the Kingdom of Scotland’s attempt to colonize the Gulf of Darién in what is today’s Panama. The Scots came equipped with a printing press and plenty of woolen socks but no earthly idea how to deal with gazillions of mosquitos that promptly wiped the colonists out. The financial hit to the Kingdom was so severe that the Scotts agreed to join forces with the English, thus forming what is today the United Kingdom of Great Britain (England, Scotland, and Wales) and Northern Ireland.

Malaria, the most common disease spread by the mosquito, is a thing of the past in much of the developed world, but the parasite still infects some 200 million people a year – killing 400,000. Children aged under the age of five are most susceptible to malaria, accounting for a majority of the fatalities worldwide. In addition to the human suffering, malaria imposes huge economic costs on some of the poorest countries in the world – nine percent of the gross domestic product in Chad, for example.

Mercifully, our most ancient enemy may have met its match. The COVID-19 pandemic sucked so much air out of the news cycle that relatively few people noted the emergence of an amazing new malaria vaccine. The injection infects people with “live Plasmodium falciparum parasites, along with drugs to kill any parasites that reached the liver or bloodstream, where they can cause malaria symptoms.” According to Nature magazine, “the vaccination protected 87.5 percent of participants who were infected after three months with the same strain of parasite that was used in the inoculation, and 77.8 percent of those who were infected with a different strain.”

In our book, Ten Global Trends Every Smart Person Should Know: And Many Others You Will Find Interesting, Ronald Bailey and I noted that thanks to better treatments and preventive measures, the malaria death rate dropped from 12.6 per 100,000 in 1990 to 8.2 per 100,000 in 2017. That incremental progress is encouraging, but we very much look forward to the day when the malaria death rate stands at zero and the disease joins the other illnesses humanity has either extinguished or contained. Last year may have been a miserable one, but it appears to have delivered not one but two important vaccines. Surely that’s something for which we should be grateful.

Blog Post | Communicable Disease

Heroes of Progress, Pt. 25: Tu Youyou

Introducing the scientist who discovered artemisinin, a compound that's used to create extremely effective malaria-fighting drugs, Tu Youyou.

Today marks the 25th installment in a series of articles by HumanProgress.org titled, Heroes of Progress. This bi-weekly column provides a short introduction to heroes who have made an extraordinary contribution to the well-being of humanity. You can find the 24th part of this series here.

This week, our hero is Tu Youyou, the scientist who discovered artemisinin – the core compound that’s used to create extremely effective malaria-fighting drugs. Tu’s work is considered a breakthrough in 20th century tropical medicine. Since artemisinin’s discovery, the compound has been used to save tens of millions of lives worldwide.

Tu Youyou was born on December 30, 1930, in Ningbo, a city on the east coast of China. As a child, Tu was fortunate enough to attend some of the top private schools in the region. At the age of 15, she contracted tuberculosis and had to take a two-year break from her studies. Fortunately for humanity, Tu’s illness inspired her to go into the medical sector, where she could try to find cures for diseases – like the one that afflicted her.

Tu returned to school in 1948. In 1951, she began studying at Peking University Medical School. Four years later, Tu was assigned to continue her research at the newly established Academy of Traditional Chinese Medicine. As her undergraduate degree focused primarily on western medicine, Tu studied a full-time course in traditional Chinese medicine between 1959 and 1962.

Tu was doing her research during China’s “Cultural Revolution” in the 1960’s and 1970’s. During that time, scientists and intellectuals were often vilified by the Chinese government and many were imprisoned, executed or sent to “re-education camps.” The government also shut down hundreds of research programs. For a brief period, Tu’s husband, who was an engineer, was taken by the government to a “re-education camp.”

Prior to Tu’s discovery, malaria was effectively treated by the drugs chloroquine and quinoline. However, in the late 1960s, new strains of malaria evolved and became resistant to the existing drug treatments. The global medical community struggled to respond to new malaria strains and the disease quickly spread, resulting in the deaths of millions of people.

Malaria’s resurgence was particularly catastrophic in South East Asia, where the disease afflicted the forces engaged in the Vietnam War. It’s reported that in 1964, malaria caused four to five times more medical disabilities than direct combat for the U.S. military alone.  As a result, tackling malaria quickly became a top medical priority for both sides in the conflict.

In 1967, Ho Chi Minh, the leader of North Vietnam, pleaded with Zhou Enlai, the Chinese premier, for a new malaria treatment for his soldiers. The early part of Tu’s career focused on trying to create a cure for schistosomiasis, a disease caused by a parasitic flatworm. In 1967, Tu was approached to join a top-secret government drug discovery program named Project 523 that would focus on developing a cure for malaria.

In 1969, Tu was appointed the head of her research group and she was sent to the Hainan region to study patients who had been infected with malaria. To travel to Hainan, Tu was forced to leave behind her one-year old and four-year old daughters. It would be three years before Tu saw her children again. Looking back at that time, Tu said “the work was the top priority, so I was certainly willing to sacrifice my personal life.”

After scientists from across the world screened over 240,000 compounds for their effectiveness against malaria without success, Tu thought it could be useful to screen Chinese herbs. By 1971, Tu and her team had tested over 2,000 traditional Chinese recipes. After searching through dozens of history books, Tu’s team found a concoction from a book from the year AD 400 titled “Emergency Prescriptions Kept Up One’s Sleeve” that used the ingredient sweet wormwood to treat intermittent fevers – a hallmark symptom of malaria.

At first, sweet wormwood proved an ineffective treatment against malaria. However, Tu found inspiration from another traditional Chinese medical book, The Handbook of Prescriptions for Emergency Treatments, written in AD 340 by Ge Hong. Tu realized that instead of boiling the sweet wormwood to extract its antimalarial properties, she should instead attempt a low-temperature extraction. Early tests on mice and monkeys proved to be 100 percent successful.

In 1972, Tu was successful in extracting the pure antimalarial substance from the sweet wormwood and named it ‘qinghaosu’ or artemisinin – as it is commonly known in the West. Tu insisted that she should be the first human test subject. Then she tested her discovery on 21 patients. Artemisinin proved to be completely effective in treating malaria patients. Tu published her findings anonymously in 1977 and the use of artemisinin in anti-malaria drugs was quickly adopted across the world.

In 1980, Tu was promoted to a Researcher (equivalent to the academic rank of full professor in the West). In 1981, she presented her findings on artemisinin at a meeting with the World Health Organization. Today she continues to work as the Chief Scientist at the Academy of Traditional Chinese Medicine, where she has worked since 1955.

Throughout her life, Tu has been decorated with numerous awards. Most notably, she was awarded the Lasker Award in clinical medicine in 2011. In 2015, she was one of three people to win the Nobel Prize in Medicine and Physiology. Tu was the first Chinese Nobel laureate in physiology or medicine and the first female citizen of China to receive a Nobel Prize in any category.

Due to the millions of lives it has saved, the Lasker Foundation described Tu’s discovery of artemisinin as “arguably the most important pharmaceutical intervention in the last half [of the 20th] century.” It is for that reason Tu Youyou is our 25th Hero of Progress.

Blog Post | Communicable Disease

Heroes of Progress, Pt. 18: Paul Hermann Muller

Introducing the man who discovered the insecticide qualities of DDT that has saved countless millions of lives, Paul Hermann Müller.

Today marks the 18th installment in a series of articles by HumanProgress.org titled, Heroes of Progress. This bi-weekly column provides a short introduction to heroes who have made an extraordinary contribution to the wellbeing of humanity. You can find the 17th part of this series here.

Our 18th Hero of Progress is Paul Hermann Müller, a 20th-century Swiss Chemist who discovered the insecticide qualities of dichloro-diphenyl-trichloroethane (DDT). The effectiveness of DDT in killing mosquitoes, lice, fleas and sand flies that carry malaria, typhus, the plague and some tropical diseases, respectively, has saved countless millions of lives.

Müller was born on January 12, 1899 in Solothurn, Switzerland. At the age of 17, Müller left school and, one year later, began working as an assistant chemist for Lonza – one of the world’s largest chemical and biotechnology companies.

In 1918, Müller returned to school. In 1919, he started studying chemistry with a minor in botany and physics at Basel University. Upon completing his undergraduate degree in 1922, Müller stayed at Basel University to study toward a PhD in organic chemistry. Müller completed his PhD in 1925. That year, he started working for J.R. Geigy, a company that specialized in “chemicals, dyes, and drugs of all kind.” It would be here that Müller made his great discovery.

In 1935, Switzerland began experiencing major food shortages caused by crop infestations, and the Soviet Union experienced the most extensive and lethal typhus epidemic in history. These two events had a profound impact on Müller. Before the 1940s, insecticides were either expensive natural products or inexpensive but made from arsenic compounds that made them poisonous to humans and mammals.

Motivated by the need to create a cheap and long-lasting plant-protection agent that was not harmful to plants or warm-blooded animals, Müller decided to switch the focus of his work at J.R. Geigy from research on vegetable dyes and natural tanning agents, to plant-protection agents.

By 1937, Müller had developed a successful seed disinfectant named Graminone, which, when applied to seeds, protected them from soil-borne pathogens and insects. After this initial success, Müller turned his attention to insecticides. After four years of intensive work and 349 failed experiments, Müller found the compound he was looking for in September 1939.

DDT had first been synthesized by Viennese pharmacologist Othmar Zeidler in 1874. Unfortunately, Zeidler failed to recognize DDT’s value as an insecticide. J.R. Geigy took out a Swiss patent on DDT in 1940 and British, American and Australian patents followed in the early 1940s.

The discovery of DDT came at an important moment in history. It played a crucial role in protecting Allied troops in the Far East, where the shirts of British and U.S. troops were often impregnated with the compound. In 1943, DDT was used in Naples to bring a typhus epidemic under control in just three weeks. Between the 1950s and the 1970s, DDT was used to eradicate malaria from many countries, including the United States and most of Southern Europe.

The use of DDT declined after 1972, when it was banned, due to environmental concerns, by the U.S. Environmental Protection Agency. As Richard Tren of the public health advocacy group called Africa Fighting Malaria noted, “while there is evidence that the widespread, virtually unregulated agricultural use of DDT … did harm the environment, no study… has shown DDT to be the cause of any human health problem.”

In 2006, the World Health Organization reversed its stance on DDT. The WHO now recommends “the use of [DDT in] indoor residual spraying” as “DDT presents no health risk when used properly.”

After his discovery, Müller went on to become J.R. Geigy’s deputy director of research for plant-protection. In 1948, Müller received the Nobel Prize in Physiology or Medicine. The fact Müller was accorded this award even though he was not a physiologist or a medical researcher highlights the immense impact that DDT had in the fight against disease.

Image result for Paul Hermann Müller

Later in life, Müller received many awards and honorary doctorates. In 1961, Müller retired from J.R. Geigy, but continued doing research in his home laboratory. In 1965, Müller died at the age of 65 in Basel.

Thanks to Müller’s work, billions of people have been able to avoid exposure to deadly diseases that have plagued humanity since the dawn of our species. For that reason, Paul Hermann Müller is our 18th Hero of Progress.

Blog Post | Communicable Disease

Progress Has Been Made in the Battle Against Malaria

Between 1990 and 2016, the malaria death rate dropped from 14.2 per 100,000 infections to 9.7.

Global Malaria incidence, death, and death-rate is declining

In 2015, malaria killed between 438,000 and 722,000 people, mostly in Africa, Asia and Latin America. On top of all that human suffering, malaria seriously hampers economic development in poor countries. The disease reduces overall labour productivity, reduces agricultural output, discourages investment and tourism, and damages educational outcomes due to high degrees of absenteeism among both students and teachers.  Repeated bouts of malaria can also compromise the cognitive development of children.

The results are stark: researchers estimate that the economic costs of malaria range from 0.41 per cent of GDP in Ghana to a staggering 8.9 per cent in Chad. It is also estimated that if malaria and HIV were eradicated, foreign direct investment in the median sub-Saharan African country could rise by as much as a third, with all the potential for growth and economic opportunities that would entail.

The word “malaria” comes from the Italian words for bad (mal) and air (aria), for it was thought that the disease was caused by foul air emanating from swamps and bogs. In 1880, French army physician Alphonse Laveran discovered that malaria was caused by a genus of parasites called Plasmodium.

Eighteen years later, British army physician Ronald Ross discovered that the malaria parasite was transmitted by mosquitoes. Soon thereafter, Italian zoologist Giovanni Batista Grassi identified Anopheles as the genus of mosquito responsible for spreading the disease. Once scientists understood the role of mosquitoes, they were able to develop programs aimed at halting the spread of the disease.

In the past, efforts largely consisted of spraying small amounts of the insecticide DDT on the inside walls of houses. Once sprayed inside, DDT repelled, irritated or killed mosquitoes. As Richard Tren of the public health advocacy group called Africa Fighting Malaria notes: “DDT’s public health applications were discovered by the Allied forces during World War II, and the United States was the primary backer of efforts to rid the globe of an ancient disease. After DDT fell out of favour due to somewhat overblown environmental concerns, new medicines and insecticides, and the use of insecticide-treated bed nets became more popular.”

Malaria is a stubborn disease, as mosquitoes tend to develop resistance to new insecticides relatively quickly, and widespread use of new tools, such as improved vaccines and genetically altered mosquitoes, are likely to be needed in the future. The sterile insect technique (SIT), for example, is an environmentally-friendly insect pest control method that involves the mass-rearing and radiation-induced sterilisation of mosquitoes.

The eunuchs are then released by air over defined areas, where they mate with wild females. The result is no offspring and a declining mosquito population. This method has already been successful in controlling a number of high-profile insect pests, including fruit flies, tsetse flies, screwworms and moths.

Environmental groups, including Friends of the Earth and the African Centre for Biodiversity, have raised concerns over the application of the SIT.

As Tren writes:

To be fair to those who oppose the genetic modification [of mosquitoes] there may be legitimate concerns, and it is right and proper to proceed with regulatory oversight … That said, there is little evidence that eliminating or dramatically reducing the populations of specific malarial mosquitoes would seriously affect other species that may rely on them as a food source. Another concern is that the technology could be hijacked by nefarious actors and even used to spread disease.  While this is possible of course, it seems far from reasonable to block new technologies on the off chance that a rogue actor might attempt to hijack them. Were this the standard, would we ever have developed chemotherapies or radiation therapy for cancer treatments?

While there are hurdles to overcome, progress is certainly being made. Between 1990 and 2016, the malaria death rate dropped from 14.2 per 100,000 infections to 9.7 and incidence declined from 15.8 in 10,000 people in 2000 to 9.4 in 2015.

There is some debate among researchers as to the number of people who die from the disease each year. But according to the World Health Organisation, deaths from malaria declined from 840,000 in 2000 to 438,000 in 2015. The Institute for Health Metrics and Evaluation, in contrast, estimates that deaths from malaria declined from 746,000 in 1990 to 720,000 in 2016. Whichever statistics we choose it’s clear that while there have been great advances in the fight against malaria, much work still remains.