7 | O akville B eaver | T hursday,June 17,2021 insidehalton.com Over 120,000 satisfied custOmers 9 Locations to serve you better Heating & Cooling www.aireonewest.ca Beat the Price increase & shortageBeat the Price increase & shortage OAKVILLE 905-849-4998 1-888-827-2665 Beat the Price increase & shortageBeat the Price increase & shortage $700 OFF HIGH EFFICIENCY CENTRAL AIR HIGH-EFFICIENCY CENTRAL AIR & FURNACE $29 /MONTH OAC* *Call for Details Starting From $2,299 10 Year Factory Warranty *Call for Details Starting From $4,999 10 Year Factory Warranty Central air diagnostiC speCial Central air tune-up speCial $59 /MONTH OAC* $4,999 * $2,299* $49* *Call for Details $79* *Call for Details Getting COVID-19 after being immunized against the virus, while possible, is highly unlike- ly. In fact, according to experts, this possibility of post-vaccine infection is not exclusive to CO- VID-19 -- it has always existed for other viruses and diseases. To understand the ways in which a vaccinated person can still get infected with the CO- VID-19 virus, it is first important to understand how the vaccines work and the amount if time it takes for immunity to take ef- fect.Here's what you need to kno- wOne dose is not enough Both the Pfizer-BioNTech and Moder- na vaccines require two doses to be effective, which means a per- son is still highly susceptible to contracting the virus after the first dose. Bryan Heit, associate profes- sor of microbiology and immu- nology at Western University, said, as a general rule, it usually takes at least 10 days after the first vaccine dose for the body to develop a reasonable immune re- sponse. "There's essentially a week- and-a-half period after you get your first vaccination where you're still completely open to in- fection," he said. While the data for the CO- VID-19 vaccine is still being as- sessed, Heit said it appears that after that period, about 50 per cent of people will be protected from getting "noticeable dis- ease." The second shot then boots the immune response further, he added. Reggie Lo, professor emeritus in the department of molecular and cellular biology at the Uni- versity of Guelph, said it will take about two to three weeks af- ter the second dose for immunity to reach the 95 per cent efficacy rate that was demonstrated in clinical trials.Science is not per- fect Both the Pfizer and Moder- na vaccines have about a 95 per cent efficacy rate, which means it will be ineffective five per cent of the time. This means that yes, people that fall in that five-per-cent range can get the virus after get- ting vaccinated, but this is the case with other vaccines as well, Heit said. "As vaccines go, 95-per-cent efficacy is actually really good," he said. "Usually you want better than 90 or 95 per cent for a vac- cine to really consider it a good public health tool. We are on par with what you would hope to see when you bring in a new vac- cine." Lo added that when it comes to immune response, nothing is 100 per cent. "In science, you cannot say anything is perfect," he said. "That is because we do not know how everybody's immune sys- tem works ... you are always go- ing to have individuals who do not respond properly." Lo said factors such as age, di- et and lifestyle can all play a role in a person's immune response to a vaccine.Protected people may still infect others Heit said research is still determining whether a vaccinated person can get infected with the virus and subsequently transfer it, but what is known for certain is that vaccine-protected people do not get any symptoms. "If they were to be infected, it is theoretically possible that they could spread the disease to someone who wasn't vaccinated, but the likelihood of that is prob- ably fairly low," he said. Lo said this is because when an unvaccinated individual in- hales a highly infectious dose, the immune system will be over- whelmed. This leads to clinical illness and becoming infectious as the virus replicates in the body. "After the individual has been vaccinated and immunity devel- oped, this will limit replication of the virus in the body and hope- fully reduce the number of virus particles exhaled to infect other people," he said. Heit said the other possibility is that vaccinated patients devel- op such strong immunity against the virus that they won't get infected at all. "That, of course, is what we're hoping for because then you completely shut down any chance of those people transmit- ting the virus, because the virus goes into their body, and even be- fore it can infect and start grow- ing, it gets cleared." CAN I STILL GET COVID-19 AFTER BEING VACCINATED? Both the Pfizer and Moderna vaccines have about a 95 per cent efficacy rate, which means it will be ineffective five per cent of the time. Julie Jocsak/MetrolandVERONICA APPIA vappia@toronto.com NEWS INFECTION IS STILL POSSIBLE UNDER CERTAIN CIRCUMSTANCES, BUT UNLIKELY: EXPERTS