Meningitis surge in Africa is linked to Sahel sand and dust storms

RIYADH, Saudi Arabia — Cases of meningitis are surging in Africa, and the United Nations links the increase to a widely ignored environmental extreme that is also intensifying amid climate change: sand and dust storms. The potentially deadly disease can be caused by bacteria, viruses, and fungi, but bacterial meningitis is the deadliest of them all and can lead to life-threatening sepsis. Around 2.3 million people globally are diagnosed with meningitis every year, and the World Health Organization estimates that it kills around one in six patients. Half of all deaths are in children under 5 years old. Meanwhile, sand and dust storms have devastating implications for the health of millions of people worldwide, particularly in Africa’s Sahel region stretching from Senegal in the west to Ethiopia in the east. The region has come to be known as the “meningitis belt,” where half of all meningitis cases occur. This is because, in Africa, potentially lethal meningitis spores can hitch a ride aboard sand and dust storms from the Sahara Desert and be transported as far south as central Africa. And since meningitis outbreaks are linked to high temperatures and airborne dust, epidemics are more common in the meningitis belt than in other parts of the world. Meningitis is seasonal, spiking during the dry season. The problem is set to worsen as dust storms are exacerbated by climate change, drought, land degradation, and unsustainable or improper land and water management. “The risk of catching respiratory diseases due to aerosols carried by sand and dust storms or the dryness that they cause to the air cycle is increasing all over the world. The storms also disrupt global supply chains,” said Ibrahim Thiaw, executive director of the U.N. Convention to Combat Desertification, or UNCCD, said at a press briefing before the convention’s 16th summit, COP16, in Riyadh, Saudi Arabia, which ended last week. The disease’s devastating impact on human health was discussed at COP16. Experts said the risk of the disease spreading can be reduced by halting land degradation and establishing early warning systems to strengthen storm preparedness. Meningitis, an inflammation of the thin membrane around the brain and spinal cord, can kill people within hours if not treated. One in five patients is left with lifelong disabilities, such as hearing loss, brain damage, intellectual and developmental disabilities, or epilepsy. “Meningitis is a threat to populations across the world and anyone can get it. Some people are at a higher risk than others. It has the potential to cause outbreaks and epidemics, resulting in rapid increases in cases,” said Brian Davies, the head of health insights and policy at the Meningitis Research Foundation. Preventing storms’ health effects Sand and dust storms form on degraded land due to wind erosion. The range where they can form is expanding, with 4.3 million square kilometers of the planet’s land — an area larger than India —having become permanently drier within the last three decades. The Sahara Desert is one of the regions of the world classified by the U.N. as hyperarid. But sand and dust storms, which are naturally occurring, also have their benefits: Long-distance transport of Saharan dust in the atmosphere can help fertilize soils as far away as the Amazon jungle. It also enhances precipitation by acting as nuclei for raindrops, according to the U.N. Still, the storms’ negative impacts on human health stretch beyond meningitis, with experts linking them to respiratory illnesses such as coughing, wheezing, and shortness of breath. Long-term exposure to dust particles and harmful pollutants increases the risk of chronic diseases such as asthma, bronchitis, and chronic obstructive pulmonary disease. Children, the elderly, and those with preexisting conditions are particularly at risk, according to Tayebeh Mesbahzadeh, a professor at the University of Tehran. In Iran, dust storms are common, especially during the dry seasons. “Sand and dust storms can also affect cardiovascular health. Fine particles can enter the bloodstream, increasing the likelihood of heart attacks, hypertension, and strokes. Additionally, the dust often carries harmful pathogens and toxic substances, which can lead to infections or poisoning when inhaled or ingested,” Mesbahzadeh told Devex. Research from Nigeria's National Center for Atmospheric Research demonstrates how environmental degradation and climate change worsened meningitis infections in the country. The results suggest that temperature increases in the future would increase infections during the early 21st century, or the period between 2020 to 2035, and late 21st century, or 2060 to 2075, in Nigeria, and seasonal outbreaks would occur a month earlier within these time spans, Davies said. Studies conducted in Ghana also showed links between climate change and meningitis. “Interviews with community members in Ghana who had experienced meningitis epidemics found that they were unanimous in their opinion that changes in temperature, as well as decreases in rainfall, were factors influencing meningitis outbreaks,” Davies said in an email. While people living in low-resource settings face greater risks due to limited access to health care and protective resources, measures such as wearing masks, using air filtration systems, and improving public awareness can prevent death from meningitis, Mesbahzadeh said. Keeping sand and dust storms at bay Long-term solutions such as land restoration and sustainable land management can also prevent the spread of the disease by reducing the frequency and severity of sand and dust storms, added Mesbahzadeh, who was recognized for her work on drought management and mitigation at COP16. Mesbahzadeh works with women around Lake Urmia in northwestern Iran to battle dust storms. The women prevent the spread of dust particles by stabilizing the soil by mixing in mycorrhizal fungi, she said. At a policymaking level, experts at COP16 recommended that governments invest in early warning systems to predict sand and dust storms. But only four accredited centers exist in the world, in the United States, Europe, China, and Saudi Arabia, according to Osama Faqeeha, Saudi Arabia’s deputy minister for environment. Saudi Arabia, in its role as COP16 presidency, launched an early warning initiative on sand and dust storms, which will partner with the World Meteorological Organization and the four regional centers to monitor the storms. “Our center provides support to the entire Middle East and North Africa region to have more reliable sand and dust storms early warning,” Faqeeha said. On the medical front, the new MenFive vaccine can protect against meningitis and underwent successful WHO-led vaccine trials in Nigeria this year. It can protect people against five of the main strains of bacterial meningitis. Meanwhile, WHO’s global road map to defeat meningitis by 2030 shows how to eliminate the disease from the meningitis belt, though it does not mention sand and dust storms. It was launched in 2021 and seeks to raise $37.5 million by the end of the decade. Still, there are gaps in meningitis awareness and resources, Davies said. “As a civil society organisation that works with individuals and groups directly affected by meningitis, the single biggest barrier is funding. Time and time again our CoMO colleagues report that there isn’t funding for meningitis awareness, prevention, or support in their countries,” he said of the Confederation of Meningitis Organisations. “This needs to change if we are serious about countries and communities coming together to defeat meningitis by 2030,” he said.