Media releases

• Measles may be first of more diseases to make a comeback, says Brock expert

  Tuesday, March 26, 2024 | By Brock University

  EXPERT ADVISORY: March 26 2024 – R0040

  With measles cases on the rise across the country, a Brock University immunologist says the highly contagious virus may be just the start of other vaccine-preventable illnesses making a return.

  “Unfortunately, I think measles is just the harbinger here,” says Adam MacNeil, Associate Professor of Immunology and Director of the Inflammation and Immunity Lab at Brock, whose research explores how immunity interacts with viruses, allergens and people’s lived experiences.

  “Measles is just the most contagious one that is going to be the first of its kind to make its presence known. In the coming years, we may see other diseases emerge that are vaccine-preventable and were essentially eradicated from our communities,” he says. “It doesn’t have to be this way.”

  While measles spreads quickly, it is easily prevented with two doses of the measles, mumps and rubella (MMR) vaccine, usually administered in childhood.

  Unlike the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that evolved throughout the pandemic and required updated vaccine formulas, the measles virus has not changed, nor has its vaccine, says MacNeil.

  “We know quite a lot about measles — how it works, how it transmits. We even know that a 95 per cent vaccination rate is required to prevent it from spreading through the community,” he says. “What has changed is the social context. After several years of living through a pandemic, talking extensively about vaccination in a highly politically charged environment, there is some understandable fatigue around the topic.”

  Interrupted and missed medical appointments combined with a proliferation of misinformation and disinformation has led to a drop in the number of children who are up to date on their childhood vaccination schedule.

  MacNeil says that despite a 98 per cent efficacy rate of measles vaccination, there has been an increase in vaccine hesitancy in recent years, with some people focusing on the extremely rare adverse risks of vaccination or making decisions based on ideological beliefs instead of scientific grounds.

  “This is a safe and effective vaccine,” he says. “The risk of an adverse outcome is so exceedingly rare compared to the likelihood of being exposed to the pathogen, especially now as we experience more measles outbreaks across the country.”

  Other people will minimize the effects of contracting measles.

  “Some people may insist measles isn’t a big deal, but measles can cause quite a number of problems, including immune amnesia, which can compromise the quality of your immune response to other pathogens,” he says. “It can lead to more serious infections down the road.”

  One of the main issues around public perception of vaccination is that people don’t realize when they’ve been spared disease, says MacNeil. While vaccines are typically administered to healthy people, therapies like antibiotics to treat a bacterial infection are given to people when they are ill. Unhealthy people can see and feel themselves getting better and are grateful for it, while a vaccinated person exposed to a virus doesn’t notice their body’s adaptive response to it.

  He offers the example of a healthy, vaccinated person who unknowingly inhales the airborne measles virus while sitting in a restaurant across the room from someone who doesn’t yet know they are sick, but who is exhaling the virus into the air.

  “They don’t realize the full-scale war their immune system launches to fight the viral invader, sparing them of any of the consequences of it,” he says. “Credits to vaccination are better appreciated at the community level, less so individually.”

  If not for themselves, MacNeil recommends people get vaccinated to help prevent the spread of disease and to protect immunocompromised people and those who are most vulnerable, such as children who are too young to receive the first dose of the MMR vaccine.

  “There’s an altruism about vaccination,” he says. “We should care about our neighbours and do what we can to help keep our community healthy and thriving.”

  Adam MacNeil, Associate Professor of Immunology and Director of the Inflammation and Immunity Lab at Brock University, is available for media interviews on the topic.

  For more information or for assistance arranging interviews:

  * Maryanne St. Denis, Manager, Content and Communications, Brock University mstdenis@brocku.ca or 905-246-0256

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  Categories: Media releases

• Brock expert explains math and science behind rarity of total solar eclipse

  Tuesday, March 26, 2024 | By Brock University

  EXPERT ADVISORY: March 26 2024 – R0039

  The rarity of a total solar eclipse, set to take place over Niagara and select areas across North America April 8, can be better understood by breaking down the math and science involved, says a Brock University expert.

  The celestial phenomenon, in which the moon completely blocks the sun and turns the daytime sky dark enough to see stars for several minutes, will be a once-in-a-lifetime experience for many who witness it next month.

  Jan Vrbik, a Professor of Mathematics who studies the movement of the sun, planets and moons, says there are four factors that make witnessing a total solar eclipse quite rare. 

  The distances of the sun and moon from the Earth

  “Even though the sun is 400 times larger than the moon, when we look at them in the sky, they appear to be practically the same size,” says Vrbik. “This is because their distances from Earth are roughly in the same 400 to one ratio.”

  It’s why the moon can obscure the sun, either partially or fully, to create a solar eclipse.

  The tilt of the moon’s orbit 

  The moon’s orbit around the Earth is not a perfect circle — it’s an ellipse — so the distance of the moon from Earth fluctuates depending on where it is along its orbit.

  “It varies by 11 per cent each month, which implies that the moon’s disk also fluctuates in size compared to the sun,” says Vrbik.

  About 35 per cent of the time, the moon’s disk is bigger than the sun’s disk, and the other 65 per cent of the time, it’s the reverse, he says.

  The intersection of the sun and moon’s orbits 

  The Earth orbits the sun once a year, while the moon circles the Earth once a month. If the sun and moon’s orbits were on the same plane, an eclipse would happen every month, but the moon’s orbit is tilted by about five degrees from the sun’s orbit.

  “This means that at most new moons, the moon is either visibly higher or lower in the sky than the sun,” says Vrbik. “Nevertheless, the moon needs to cross the plane of the sun’s orbit twice during its monthly cycle, at an intersection called a ‘node.’ Eclipses happen only when, during a new moon, the sun’s direction is closely aligned with one of these nodes, which happens regularly twice a year.”

  He says 23 per cent of solar eclipses are ‘total,’ when the moon fully covers the sun, and 42 per cent are ‘annular,’ when the moon’s disk is smaller than the sun’s disk and a ‘ring of fire’ is seen.

  “Thirty-five per cent of solar eclipses run so much off the Earth’s centre that only a partial eclipse is observed on one side of the globe — with the actual path of totality missing the Earth entirely,” he says.

  The moon’s shadow along the path of totality 

  For both an annular and total solar eclipse, the moon’s shadow needs to cross the Earth’s surface.

  The size of the moon’s shadow varies depending on how close in time the event is to when the moon is at its closest to Earth. Typically, the shadow is 150 kilometres (km) in a circular area. A much larger part of the Earth’s surface, about 7,000 kms across, will at the same time experience a partial eclipse, in which only a part of the sun’s disk is covered by the moon.

  Vrbik says the shadow’s path across the globe is a combination of the moon’s straight-line motion of about one km per second and the Earth’s rotation of close to 0.5 km per second, complicated more by the fact that the Earth’s axis is tilted.

  If people are in the right place at the right time, they can witness a total solar eclipse for three to four minutes.

  Adding it all up

  “When one considers the movement of the sun, the Earth and the moon, as well as their orbits, speed, distance and alignment from each other, it is easier to understand why a total solar eclipse is so rare,” says Vrbik.

  While a total solar eclipse occurs on Earth every 18 months, it usually occurs over water. The last time a total solar eclipse occurred over Ontario was in 1979. The next one won’t happen again over the province until 2099.

  “If you know the length of each celestial body’s cycle, you can easily predict when an eclipse will happen again,” he says. “Experiencing a total solar eclipse from a specific location is a rare privilege, typically separated from the next such occurrence by several centuries.”

  Vrbik will be among a group of Brock experts leading discussions and educational exhibits around the solar eclipse during ‘Eclipse on the Escarpment,’ a free community event being held on Brock’s main campus Monday, April 8.

  Brock University Professor of Mathematics Jan Vrbik is available for media interviews on the topic.

  For more information or for assistance arranging interviews:

  * Maryanne St. Denis, Manager, Content and Communications, Brock University mstdenis@brocku.ca or 905-246-0256

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  Categories: Media releases