YES. Rats can transmit over 70 types of diseases which are serious threats to our health.
One of the common diseases caused by rats is leptospirosis. This type of bacterial disease is transmitted when water that has been contaminated with animal urine, such as that coming from rats, comes in contact with unhealed breaks in the skin, eyes and mucous membranes. Untreated leptospirosis could lead to the development of kidney damage, meningitis, liver failure and respiratory distress. In some cases, it may even cause death.
Humans can get infected with lymphocytic choriomeningitis by inhaling infectious aerosolized particles of rodent urine, feces or saliva, by ingesting food that has been eaten by rats with this virus, or by exposure of open wounds to a rat’s infected blood. Once infected, the person will suffer from fever, muscle aches, appetite loss, headache, malaise, nausea and vomiting. Lymphocytic choriomeningitis is especially dangerous to a fetus. If a pregnant mother is infected during the first trimester, there is an increased risk for spontaneous abortion. If the infection occurs after the first trimester, congenital infection may lead to malformations such as chorioretinitis, intracranial calcifications, hydrocephalus, microcephaly or macrocephaly, mental retardation, and seizures.
Rats are also known for carrying a disease called Hantavirus. It is transmitted through rat’s urine and feces. It may cause fatal diseases in humans such as hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS). Hantavirus may cause cardio vascular shock and hospitalization is required for those infected with this disease.
An infection of the brain called eosinophilic meningitis can be caused by a worm that resides in a rat’s lung. They are expelled from a rat’s body via the feces of the rat. In some cases, patients develop weakness or life time blindness as a result of this infection.
The Bubonic Plague which swept through Europe in the 14th century and which killed about 25 million people was thought to have been caused by fleas of rats. Without treatment, the bubonic plague killed about two thirds of the infected humans in 4 days. The common symptom of the bubonic plague is the infection of the lymph glands (lymphadenitis). The lymph glands become swollen and painful. The medieval doctors were unaware that the rat fleas were causing the massive deaths at the time. Their recommended treatment of the plague was good diet, rest and relocating to a non-infected area. What they did not know was that their recommendation of moving to a non-infected area meant that the public was getting away from the rats that were the hosts of the fleas that were carrying the infection.
From the past up to the present, rats are indeed dangerous.
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