On 11th November 2017, in Kutupalong hospital, I diagnosed the first case of diphtheria in the refugee camp. Although I had never seen this illness during my professional career, it was instantly recognisable. Three weeks later, the hospital was seeing a hundred Rohingya patients a day suffering from diphtheria, with a mortality rate of 10%.
In 19th Century Britain, diphtheria was known as “Boulogne Sore Throat” as there was an outbreak across the Channel in France. Queen Victoria’s second daughter and her grandchild died from diphtheria within a week of each other.
The French physician Bretonneau first used the Greek word diphthera meaning “prepared hide or leather” to describe the disease in 1826. It refers to the thick, grey membrane of dead skin which covers the back of the throat in patients suffering from diphtheria. This “pseudomembrane” can obstruct the airway, suffocating the patient. No wonder the disease was known as the “strangler”. An epidemic struck Spain in 1613, “el ano de los garrotillos” (the year of strangulations).
People can be asymptomatic carriers of non-invasive diphtheria which do no harm. But when a bacteriophage (virus) infects the corynebacterium it stimulates the production of the dangerous toxin. This poison kills cells in the throat but has a more serious, delayed action which damages the heart, kidneys, liver and nervous system.
A Prussian military doctor, Emil von Behring, won the first Nobel Prize for Medicine in 1901 after developing diphtheria anti-toxin in 1890. He repeatedly injected sublethal doses of toxin into a horse. The horse’s immune system neutralised the toxin. Horse serum anti-toxin is still used today to treat diphtheria. However, it is in short supply as there are so few cases of the disease in developed countries. Since mass immunisation against diphtheria was introduced in the UK in 1940, the disease has become extremely rare. The last British fatality was in 1994 when an unimmunised child picked up the infection on a trip to Pakistan.
Diphtheria is part of the WHO childhood immunisation schedule. Unfortunately, many of the Rohingya children who fled from Myanmar last year had never been vaccinated. In the overcrowded conditions in the refugee camp, diphtheria can spread rapidly by droplet (aerosol) transmission. Over 300,000 young people needed immunising – three doses, a month apart – to halt the epidemic.
The outbreak in Kutupalong refugee camp in Bangladesh was not an isolated event. Last year there were serious epidemics in Indonesia and war-torn Yemen, with many fatalities.
I have always been a fervent believer in immunisation because I am convinced it prevents mortality and morbidity. Perhaps because it has been so successful at eliminating diseases such as tetanus, measles, rubella, polio and diphtheria, many parents are unaware how deadly these diseases can be and they are frightened about the infinitesimal risk of vaccine side effects. But I have seen what happens when the system for vaccinating children breaks down, resulting in death and misery.