The news of infant deaths on September 16 in northern Syria from measles vaccination is heartbreaking. Shortly after vaccination, the children became limp and unresponsive: those most severely affected died before reaching hospital. Seventy-five children were sickened, and fifteen died. The World Health Organization is investigating the incident.
The first reports couldn’t identify the problem and speculated that the vaccine had spoiled or that it had been tampered with. The latest reports state that atracurium, a neuromuscular blocking agent used in procedures like intubation, was used as a diluent for measles vaccine, rather than the standard water-based diluent.
Errors like this are not unknown. David Kroll on his Forbes.com blog lists several similar recent occurrences. Reports have noted that the packaging for the muscle relaxant and the diluent are similar.
Mass vaccination disasters like this one in Syria are, thankfully, incredibly rare. In an earlier era, they were more frequent. One of the most notorious incidents was the Lübeck, Germany, disaster of 1929-1930. In that case, contaminated BCG vaccine was given to infants. The vaccine contained viable bacteria that cause human tuberculosis (the vaccine is made from attenuated bovine TB bacteria). About 250 infants received the vaccine, and 75 of them died. Many others contracted TB from the vaccine.
An incident close to home here in Philadelphia occurred in 1901. In this case, smallpox vaccine was likely contaminated with tetanus bacteria during manufacture. Nine children died of tetanus. A similar event happened in St. Louis that year: thirteen children died from tetanus after receiving contaminated diphtheria antitoxin. (See DE Lilienfeld’s essay on these incidents for more detail.)
In 1928, bacterial contamination of diphtheria toxin-antitoxin mixture in Bundaberg, Queensland, Australia, led to the deaths of 12 children. Five other children became critically ill but recovered. A multi-use bottle of toxin-antitoxin mixture, containing no preservative, was improperly stored and reused.
The American events in 1901 led to early legislation to oversee biologics production. Some commenters now say that vaccines are subject to tougher safety standards than most other pharmaceutical products. But medical errors are a different thing altogether: though much attention has been focused on preventing them, they still happen, sometimes with devastating consequences. In the case of Syria, the need for vaccination campaigns is huge, give the disruption of the populace and the recent re-appearance of polio there. Medical and relief workers will try to address the problems that led to the mistake, and equally importantly, rebuild trust and confidence among Syrians.