Rats can detect diseases, according to a 2014 research study in Tanzania. Scientists trained African giant pouched rats to sniff human saliva samples to determine which ones are positive for tuberculosis, a bacterial infection affecting the lungs. Standard tuberculosis detection by humans in a laboratory consists of examining saliva and mucous samples under a microscope and can take an entire day, while the trained rats typically take around seven minutes. The rodents have a much stronger sense of smell than humans: for every one sniff a human’s nose takes, a rat’s nose can take eight sniffs. They can also smell multiple scents at one time and differentiate between them.
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