They also feared that it increased the odds that a person could become infected with chickenpox later as a young adult, when the rash is more painful and prevalent and can last up to three or four weeks. In other words, scientists considered the benefits of the vaccine to be temporary when given to young children. centered on observations made by scientists that the vaccine simply did not last long enough and did not confer a lifetime of immunity.
Although the appearance of chickenpox and shingles within one person can be many years apart-generally many decades-the increased risk in developing shingles as a younger adult (30-40 years old rather than 60-70 years old) proved to be enough to convince the medical community that immunization should be preferred to the traditional alternative.Īnother reason that the chickenpox vaccine was not immediately accepted and used by parents in the U.S. encouraged the development, adoption, and use of a vaccine against chickenpox to the public. As a result, the medical community in the U.S. They reached the conclusion that Varicella zoster remains dormant inside the body, making it significantly more likely for someone to develop shingles. Strong belief in that view eroded when scientists discovered the link between Varicella zoster, the virus that causes chickenpox, and shingles, a far more serious, harmful, and longer-lasting disease in older adults that impacts the nervous system. Mothers and fathers typically cited the notion that chickenpox did not constitute a serious enough disease against which a person needed to be vaccinated. Yet even though the chickenpox vaccine was available and recommended by the FDA, parents did not immediately choose to vaccinate their children against this disease. government’s seal of approval for widespread use in 1995. Food & Drug Administration (FDA), finally earning the U.S. However, it took over 20 years for the chickenpox vaccine to be approved by the U.S. Japan and several other countries began widespread chickenpox vaccination programs in 1974. Takahashi began his work to isolate and grow the virus in 1965 and in 1972 began clinical trials with a live but weakened form of the virus that caused the human body to create antibodies. Over time, the fruits of this research have transformed attitudes toward the disease and the utility of seeking preemptive measures against it.Ī vaccine against chickenpox was originally invented by Michiaki Takahashi, a Japanese doctor and research scientist, in the mid-1960s. This view, however, was altered after additional research by scientists demonstrated unexpected dangers associated with the virus. and thought to provide children with greater and improved immunity to other forms of sickness later in life. The ailment was once considered to be a “rite of passage” by parents in the U.S. Individuals infected with chickenpox can expect to experience a high but tolerable level of discomfort and a fever as the disease works its way through the system. The disease can last for up to 14 days and can occur in both children and adults, though the young are particularly vulnerable. History of the Chickenpox VaccineChickenpox is a highly contagious infectious disease caused by the Varicella zoster virus sufferers develop a fleeting itchy rash that can spread throughout the body. For each individual Speaking and Writing task, follow the time limits you’ll see in the instructions. For the most accurate results, give yourself 54 minutes to complete the TOEFL Reading section and 41 minutes to complete the TOEFL Listening section. The Magoosh TOEFL Practice Test starts here. Where can I find more TOEFL practice tests?.Why do I need to take a TOEFL practice test?.
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