“Eating Marmite and garlic doesn’t work,” says Dr James Logan, a senior lecturer at London School of Hygiene and Tropical Medicine, busting the myth that travellers can make themselves unappealing to malarial mosquitoes by adjusting their diet prior to a trip. I’m learning about the disease that last year killed around 600,000 people during an event organised by the charity Malaria No More (UK) at Portcullis House, part of the Houses of Parliament.
The lifecycle of malaria is chillingly efficient. “Once mosquitoes are infected,” explains Dr Logan, “the parasites [Plasmodium falciparum] which carry the disease end up in the insects’ saliva glands and their sense of smell sharpens, making it easier for them to find new victims.” Recent research also shows that humans become more attractive to mosquitoes once they are infected.
I listen as a doctor gives a graphic description of how malaria affects people:
Malarial mosquitoes will bite you and inoculate parasites into your blood but you won’t feel anything for about a week, while those parasites work their way through your bloodstream to your liver, where they undergo a development process.
After about a week each of those parasites in your liver rupture and they release something like 30,000 to 50,000 parasites.
The reason malaria is so deadly is the fact those parasites then invade your red blood cells and they eat the globin – part of the haemoglobin – and that’s a pretty essential part of your body. It’s what carries oxygen around your blood. Those parasites replicate every 48 hours.
Within seven days of coming out of the liver you can have three per cent of a child’s red blood cells infected. That’s a huge burden if you think that a child only has a litre of blood.
Those parasites, to ensure their survival, stick in some of the blood vessels in the brain. This is what we know as cerebral malaria…the parasite blocks the flow of blood to the brain, which can cause fits, seizure and death.
Looking at slides under a microscope I experience how tricky it can be to spot low levels of the dot-like parasites in blood samples. The technique, known as microscopy, is used in endemic areas. Last year 120 million of the tests were carried out in India alone.
I’ve always thought of malaria as a tropical disease, possibly due to the fact that 90 per cent of annual deaths it causes occur in Africa. I hear how the negative impact of malaria on Africa’s economy is estimated to cost £8 billion ($13.4b) a year, affecting around 72 per cent of companies. Yet progress is being made. The number of child deaths from malaria was halved between 2010 and 2013.
The disease was once much more widespread across the world. According to the most recent reports malaria is transmitted in 97 of the world’s countries and 3.4 billion people are at risk of infection. Remarkably, it wasn’t until the 1950s that its transmission was eradicated in both the UK and the USA.
“This is one of the world’s largest killer diseases which is totally avoidable and totally treatable,” says Stephen O’Brian, MP for Eddisbury, addressing attendees, including members of the All-Party Group on Malaria and Neglected Tropical Diseases (APPMG). “We have the chance of a generation to beat malarial mosquitoes,” he adds.
Travellers can minimise their risk of infection by sleeping under an insecticide treated mosquito-proof net and taking preventative medicine while travelling in endemic regions. “We also recommend people buy and use the strongest DEET repellent available and wear light, long, breathable clothing that covers their arms and legs,” says Angela Aboagye, a public health worker who provides advice on prevention and treatment at the pop-up Malaria Shop active in London’s Peckham district.
Treated mosquito nets, with an effective life span of three to five years, can cost under £5 (around $7) and are now widely used in some endemic regions of Africa. Testing a person for infection costs around 36 pence (60 cents) while effective treatments are as little as £1 ($1.50).
Yet, Jeremy Lefroy, MP for Stafford and chairman of the APPMG, points out that there’s a danger progress and apparent success in combating the disease will result in complacency.
“People tend to think it’s done, it’s finished, we’ve done enough. But actually the experience is that, in the past, we think we’ve conquered malaria. In Zanzibar in the 1960s malaria was down to an extremely low level. People thought “that’s it, we’ve sorted it out.” We took the foot off the gas and it came back with a vengeance and millions and millions of people in the 60s, 70s, 80s and 90s because we did not take malaria seriously enough as a global community,” says Lefroy, urging continued action.
World Malaria Day, on 25 April, aims to raise awareness of the continuing dangers and global impact of malaria.
Malaria No More (UK) - A charity whose goal is the eradication of malaria.
All-Party Parliamentary Group on Malaria and Neglected Tropical Diseases - a group of British parliamentarians whose aim is to inform parliament of the destruction caused by malaria.
London School of Hygiene & Tropical Medicine - A leading institute for health-related research and education.