While this isn’t the first typhoid vaccine, it’s the most effective one — and it also works for children.
Typhoid is an acute illness associated with fever. Caused by the Salmonella Typhi bacteria, it affects a whopping 20 million every year, killing 160,000 of them — mostly young children in developing countries. Aside from the fever, symptoms include abdominal pain, constipation, and severe headaches. Without treatment, symptoms can continue for weeks.
The disease used to be prevalent in America, but it’s now mostly found in Africa and Asia. It occurs predominantly in association with poor sanitation and lack of clean drinking water.
As if the threat of typhoid wasn’t big enough, the need for an effective, affordable vaccine has risen dramatically as crowded slums emerge, especially in hot and wet climates. The CDC states that “without therapy, the illness may last for 3 to 4 weeks and death rates range between 12% and 30%.” Antibiotics do exist, but they’re expensive, and antibiotic-resistant strains have been on the rise. This is where vaccines can make a huge difference.
The new vaccine is called Typbar TCV, with TCV standing for Typhoid conjugate vaccine. It’s made by Bharat Biotech, a company from Hyderabad, India, and it can be purchased by governments as well as donors — including United Nations agencies. GAVI, the Vaccine Alliance, has already announced that it has $85 million set aside for doses to be given to children starting next year.
Existing typhoid vaccines can prevent about 30% to 70% of cases during the first two years, having a diminished effect for up to seven years. Meanwhile, results, published in the Lancet last year show Tybpar TCV to be 87 percent effective and can also be administered to children over six months old. It also has longer-lasting immunity and costs as little as $1.5, when purchased for developing countries. Prices go down the more doses are purchased.
Researchers also expect the advent of vaccines to curb the use of antibiotics and thus make them more effective when they are necessary.
Interestingly, the vaccine received approval after a very unusual trial: about 100 healthy volunteers in Oxford, England, most of whom were medical students, agreed, to trial the vaccine on themselves, swallowing a hefty dose of live typhoid bacteria.
Research for this vaccine was funded by donors, including the Bill and Melinda Gates Foundation, the Clinton Health Access Initiative, and the Wellcome Trust. Around 300 people still get typhoid fever in the United States each year, mostly from tourists.
Enjoyed this article? Join 40,000+ subscribers to the ZME Science newsletter. Subscribe now!