A New study has tipped man’s best friend as a potentially strong tool for fighting malaria. How do dogs figure in the malaria war you ask? The research explains.
Some dogs were trained to identify whether someone was infected with malaria simply by sniffing their socks, according to the research, published Monday.
This isn’t the first time dogs have been trained to use their nasal senses to detect diseases like cancer and diabetes. Now, UK scientists have helped train two dogs to detect malaria parasites, aided by the British organization Medical Detection Dogs.
‘People carrying malaria parasite already have a signature scent, and we know if dogs can smell drugs, food, and other substances, they should be able to detect this smell on clothing, too,’ said Steve Lindsay, a public health entomologist at in the Department of Biosciences at Durham University and lead investigator on the study.
The research was done in the Gambia where the team collected socks of 600 schoolchildren ages5 to 13 who did or did not have malaria. The socks were used to train the dogs in the UK for over four months.
‘We took the socks that had captured the scent of the children overnight and flew them to the UK, where the dogs were trained to smell and differentiate samples that were infected or not,’ Lindsay said.
Of the samples, 175 were used to train the dogs: 30 from children infected with malaria and 145 from uninfected children.
By smelling the socks alone, the dogs — Lexi, a Labrador-golden retriever, and Sally, a Lab — were able to accurately detect 70% of infected children and 90% of uninfected children.
The study shows that dogs can be deployed as tools for malaria detection, as they have in the diagnosis of some forms of cancer, according to the researchers.
Dogs have millions of sensors in their noses that make them more sensitive to odors than humans are.
This is however only a pilot study and more research are needed. Samples from other countries also need to be tested before the animals can be used in the field, researchers have said. The particular strain of malaria may also impact detection rates and that too has to be researched.
There were an estimated 216 million cases of malaria globally in 2016, including 445,000 deaths, according to the World Health Organization. The disease can be treated, but there is no preventive vaccine.
The researchers believe their findings could be useful in detecting malaria in people showing no signs of fever, a common symptom, therefore preventing its spread, particularly in countries that have eliminated the disease. Identification would also help people get treated early with antimalarial drugs.
‘It is useful in countries like South Africa, close to elimination, or Sri Lanka, that has eliminated malaria. How do you locate that one person in a million people carrying the parasite in a country that has recorded no infection without doing invasive tests?’ Lindsay said.
The method may not be effective in endemic countries such as Nigeria, where malaria is actively transmitted, Lindsay said.
‘The dogs are good in countries where they are going to zero infections or where they are malaria-free, and you have to prevent people from bringing malaria into the country … through the airport or the ports.’
Claire Guest, CEO of Medical Detection Dogs, said she is excited by the results and the potential for its cost-effective application in the diagnosis of tropical diseases. A dog named Freya has been trained to detect malaria since the initial study.
‘I believe that this study indicates that dogs have an excellent ability to detect malaria and if presented within an individual infected with the parasite or a piece of recently worn clothing, their accuracy levels will be extremely high. This is a reliable, non-invasive test and is extremely exciting for the future,’ Guest said.