Scientists and health advocates have been racing to find a safe vaccine for cryptococcal meningitis. A new trial is examining two new candidates and two new strategies for the battle.
An unprecedented international campaign to bring together countries, health centres, nonprofit groups and vaccine manufacturers to fight the deadliest form of meningitis is at the dawn of the most critical phase yet.
As the deadline for new cases to be reported from around the world draws closer – on 8 September – the international group of experts meeting at the Leiden, the Netherlands, World Health Organization conference in a fortnight will take their collective finger off the pause button.
Meningitis A meningitis. (Credit: Linkedin/Matt Hobin)
The disease has killed over 30 people so far this year in New York, Thailand, Australia, Tanzania, India, Ghana, Tanzania, France, France, Romania, New Zealand, the Philippines, Nigeria, the UK, and the US. Deaths are reported from Mongolia, Thailand, Pakistan, Pakistan, Kuwait, Nepal, Australia, the US, India, Thailand, Brazil, Ethiopia, South Africa, India, Thailand, Nigeria, Morocco, Senegal, Tanzania, France, Singapore, Mozambique, India, Mexico, Canada, South Africa, Turkey, Japan, Chile, France, Cambodia, Russia, South Africa, Madagascar, Colombia, Canada, and Indonesia.
Despite the heatwave in South Africa, the mass deaths there are concentrated in nine provinces. Mexico is also now reporting unusually high disease in recent weeks, with high levels of the disease.
A death in Seychelles on 22 June, just weeks after the death of an infant in Madagascar.
A rise in meningitis B cases in both Israel and Botswana.
Even countries that have not reported any deaths in the past few years are “getting hit hard”, says David Winkler, a leading expert on meningitis in Israel.
The multilateral effort was triggered in 2015 by a mass death in the Brazilian city of Campina Grande, raising awareness around the world. Since then, three WHO-led research groups have been chipping away at the problem with promising results.
Surveys led by an American doctor, Remi Leclerc, indicate that the universal vaccination against meningitis B is more than 90% effective worldwide, and that a vaccine against meningitis A could be 92% effective.
Surveys led by a team in Spain indicate that the vaccine is effective against both forms of the disease, and that a single shot – the majority of sufferers are missed if given as a “bridge” – could be 90% effective.
But while these studies offer some hope of future protection against meningitis B, both studies have received unusually harsh criticism. The Spanish group’s survey revealed that 67% of the suspected meningitis B sufferers were unaware that they had been inoculated. That was particularly distressing, says Sir John Watson, the British medical historian who attended the recent Leiden meeting on boys and men.
The Israeli studies were seen as a “human resources disaster” by the French conference, says Vivien Huesfers, a fellow at the French biotechnology company Medicago. As it relies heavily on volunteers, recruiting local patients and doctors is key to its success.
So far, all four vaccination campaigns have been big flops. The FDA declined to grant approval, as it felt there was insufficient evidence of effectiveness. The results of the two new vaccines under development are fraught with uncertainty.
The first candidate from Medicago is currently in clinical trials. Thriva, the second, is in phase three trials by the US pharmaceutical company Quintiles. The FDA has put it on a fast track for approval, as it aims to finish the trial by year-end.
Because meningitis A is of a similar strain to meningitis B, the drugs are designed to be stockpiled in the event of a global outbreak. Around the globe, people with meningitis B have to wait up to 12 months until their vaccines arrive.
In the past year, the WHO has embarked on its biggest outreach to education the public on meningitis. It spent $10m on TV advertising, a $25m program to encourage universal vaccination, and at least $100m in general outreach, tracking down doctors in the field, sending assistants on the ground, and advising parents and families about prevention.
It also conducted an unprecedented public health campaign with 21 national public health departments, mobilising more than 3,000 health workers and hundreds of volunteers on the ground. Each country has been