Word: viruses
(lookup in dictionary)
(lookup stats)
Dates: during 1950-1959
Sort By: most recent first
(reverse)
...There was a hard-to-down suspicion that more live virus particles than a child can tolerate had slipped through in some of this year's vaccine...
...Public Health Service made a hurried check. All reported cases of polio among vaccinated children were youngsters who had received vaccine made by the Cutter Laboratories. This raised the agonizing possibility that a batch of vaccine had gone through with some live virus in it. Like all vaccines, the Salk preparation contains germs of the disease that it is meant to fight. In the Salk process, these virus particles are killed, with formaldehyde, so that they cannot keep the power to infect (but retain the power to help the system build antibodies). Although this apparently did not happen...
Just what could have gone wrong? No one may be sure for weeks (or even years). But one difficulty is suspected by doctors. The formaldehyde to kill the virus must be used in just the right amount: too little leaves some deadly live virus; too much may destroy it so thoroughly that it cannot stimulate the production of antibodies. This means a narrow margin of safety. Last year's Salk vaccine, made in small pilot plants under laboratory conditions, apparently succeeded in staying within this margin. But it may develop that the margin is too slight for large-scale...
...Samples of vaccine are mixed with cultures of monkey-kidney tissue. If the tissue cells go on growing normally, there is no active virus present. Also, as one of numerous further checks, vaccine is injected directly into the brains of monkeys, where any live virus would quickly cause paralysis...
...shipping anything: instead, it is piled high with boxes full of bright red vaccine, being returned for testing from all over the U.S. The job will take weeks. As for the children already vaccinated, the evidence might be almost as long in coming. The incubation period-when polio virus can be multiplying in the human body without causing detectable symptoms-varies from three to 35 days. And the vaccine does not begin to be effective (that is, to develop antibodies against the multiplication of the virus) in less than seven to ten days...