HOW DO VECTORS SPREAD DISEASES

• the two vectors that spread numerous infectious diseases are mosquitoes and flies
• a mosquito that alr has pathogens in its salivary glands will suck the blood -> mosquito then secretes saliva when sucking the blood to prevent blood clotting, so the infection spreads throughout the body -> another mosquito that bites the infected person transmits the disease to a new victim.
• a fly that lands on dirt has pathogens on its legs and body -> fly transmits the pathogens to the food -> the pathogens from the food will enter the body of the person who eats it.