Several human diseases caused by protozoa are transmitted by a variety of arthropod vectors (Table). The vectors are not simply 'flying syringes', but represent a second host for the protozoan parasite.arasites which reside within the blood or internal organs of the host have logistical problems in terms of infecting a new host. In contrast to fecal-oral transmission, where infective stages are excreted into the environment, potential new hosts would not normally come into contact with the parasite.
If you have accumulated enough work credits (typically 40) the earliest you can collect Social Security retirement benefits is 62. At that age, your monthly payment would be about 75% of the amount you would receive by waiting to retire at SSA's full retirement age. Full retirement age:
The earliest you can apply for Social Security retirement is three months before you turn age 62 to receive your first check in the month you become 62 years old. When you apply for Social Security after age 62, you can designate the month you want benefits to begin from the current month up to four months in the future. Social Security benefits are paid in the month after they are earned, so if you elect to start your retirement benefits for the current month, the first check will arrive next month. As a result, you can delay applying for Social Security on a month-to-month basis until the month before you want to get your first payment.