What Are the Causes of Liver Spots? The appearance of liver spots is quite common in men and women over the age of 40. Liver spots develop over time, usually taking years to appear, and, although they have the word liver in their name, these dark patches on the skin have nothing to do with the human liver or liver disease.
Mosquito vectored diseases include protozoan diseases, i.e., malaria, filarial diseases such as dog heartworm, and viruses such as dengue, encephalitis and yellow fever.
Transmission of Yellow Fever Virus: Infected Mosquito. Transmission of the yellow fever virus occurs in two main ways: urban (mosquito bites an infected human) and sylvatic (mosquito bites an infected monkey). Urban. Urban yellow fever transmission occurs when a mosquito bites an infected human. Once infected, this mosquito can then bite and infect another human.