– People with parasites of malaria produce specific scents in the skin. We have found that dogs that have a sensible sense can be trained to detect these odors. This also applies to clothing used by infected people, said Steven Lindsay at the Department of Biological Sciences at Durham University in the UK and a senior researcher for a new study on malaria.
He recently presented his conclusions at the annual meeting of the American Society for Tropical Medicine and Hygiene.
Sniffed on socks
Several hundred Gambian school children took part in a new survey. First, they went through an overall state check, then tested for malaria parasites. They then got some socks that can be used overnight. The following day, the researchers collected their socks and divided them into a childhood malaria infection condition. They only collected socks for children infected with malaria without symptoms and socks of fresh children. The socks were sent to England. Here they were frozen, while sniffing dogs were trained.
The sniffing test was about to distinguish between child socks saturated with malaria and healthy children. They should charm each pair of socks and freeze if they think they have found malaria mites. If they did not feel, they should go on.
The result of the test showed that dogs were able to identify 70 percent of socks of children infected with malaria and 90 percent of healthy children.
Malaria parasite mutates
Scientists say the impact accuracy is impressive, and dogs have been able to identify socks for children with a lower degree of infection than required by the World Health Organization's (WHO) rapid tests.
Diagnosis of malaria is generally performed by blood samples and microscopy. It can be time consuming and you need special skills. You can also use fast blood tests, but they are quite expensive. They have high precision.
Scientists were aware that it was so-called proof of conceptstudies to show that malaria can be diagnosed with dogs. He further believes that the accuracy of olfactory dogs can be as good as blood testing. Lindsey justifies this because parasites of childhood malaria are not always the same way as they go through different stages of the disease. The smell they create in human skin will then change.
It stresses that the tests used today may also be short because malaria parasites are changing. Therefore, the parasite need not have the specific protein that is necessary for clinical trials to show infection
In addition, scientists believe that the ability of sniffing dogs to detect certain odors associated with malaria may be an inspiration for the development of emerging and artificial electronic noses that may feel ill.
Rangers of malaria on the border
Lindsey believes that sniffing dogs can be useful when health authorities want to check villages for malaria carriers that have no visible signs. By being a carrier, you can carry parasites of malaria to local mosquitoes. The only way to prevent spread today is to try or treat everyone in the village.
Investigating scientists, therefore, believe that sniffing dogs will work well at border crossings, to countries where malaria is almost eradicated. Lindsey draws from the East African island of Zanzibar, where the removal of the parasite of malaria was difficult due to the constant flow of immigrants.
Too little accurate
Gunnar Hasle is an infectious disease specialist and runs the Reiseklinikken in Oslo. He says the preliminary 70 percent success rate is too low.
"This means that the method is unnecessary when we find out if a person with a fever has malaria because it is unacceptable that the errors would have been closed at 30 percent.
It also points to 90 percent of those who were healthy, and 10 percent get an inappropriate report on malaria.
"It's an unacceptably high number if the method is to be used to feel many healthy people," he says.
Blood test at the clinic, dogs at the border
Hasle also states that odor indicators have been used for hundreds of years. Among others, it is possible to succeed in diabetes, by inhalation of acetone odor or removal of nail polish. It is also possible to feel liver failure because the spirit has a sweet smell.
"She also tried to get dogs to diagnose lung cancer," Hasle said, referring to the 2012 survey. The result was about the same as in the malaria experiment.
He believes that it is absolutely impossible to use dogs to diagnose clinics and that it will be difficult to train a sufficient number of dogs to satisfy the need
– Any troop medical unit should have access to malaria diagnostics. Then it is much easier to get quick tests that you can use after a minimum of training than to get trained dogs.
However, he believes they can help in some cases and support the idea of researchers using olfactory dogs as malaria guards.
"Stubborn dogs can be used for bulk screening on immigration into an area that has removed malaria," he concluded.