Despite the concern aroused a case of poliomyelitis discovered in New York State in July, Bay Area infectious disease experts say the risk to the vaccinated public is virtually non-existent – although the fact that any case has emerged underscores the need to ensure that people, especially children, have been vaccinated.
“I would say there is mild to moderate concern,” said Dr. Peter Chin-Hong, an infectious disease expert at UCSF, but “it all depends on whether your children have been vaccinated or whether you have been vaccinated “.
He said that in the larger scheme, cases detected elsewhere are not a concern due to very high vaccination rates in the United States – most children are vaccinated at an early age – meaning the virus hits a wall of immunity and is almost always unable to spread.
However, there is reason to be vigilant.
The The New York Times reported that a case of poliomyelitis has been confirmed in a 20-year-old man from Rockland County who is part of an ultra-Orthodox Jewish community. The disease has since been detected in New York City wastewater, raising further concerns.
Some Orthodox communities give up vaccination, meaning “it’s not at all unexpected” that a case could occur, said UCSF infectious disease expert Dr. George Rutherford. The Rockland County infection was one such case, According to the CDC.
However, Rutherford echoed Chin-Hong in noting that high vaccination rates in California and the rest of the country mean that “the chances of someone getting polio here unless they’re part of the one of these unvaccinated communities sucks.”
He noted that polio vaccines contain an inactive piece of virus and cannot cause vaccine-derived polio. Oral polio vaccines are cheap and can be easily administered, which is especially important in poor countries with weaker health systems.
The virus is usually spread by fecal-to-oral transmission, which means children are usually at a higher risk of contracting it. It can lead to paralysis and other long-term problems such as muscle weakness, and can be fatal when it affects the muscles involved in breathing.
Experts and health officials are alarmed by this latest virus detection because about 1 in 200 polio cases results in paralysis, said Dr. John Swartzberg, an infectious disease expert at the UC Berkeley School of Public Health. It’s particularly concerning that the virus has been detected in New York City’s sewage, meaning it’s circulating there, Swartzberg said.
He blamed much of the blame for the resurgence of the virus on the anti-vaccination movement, which has gained traction during the COVID-19 pandemic.
“We wouldn’t have seen this young adult in New York who is now paralyzed for the rest of his life if the anti-vax movement hadn’t directly driven the bad thinking” around vaccination, he said. .
Swartzberg remembers standing in line to get vaccinated as a child in the 1950s, which at the time felt like a miracle.
“It is unacceptable that we allowed this to happen,” he said. “People just don’t remember and weren’t alive in the 1950s when every family was affected by polio, including mine.”
While the new mRNA vaccine technology used in COVID-19 vaccines has given some skeptics pause, Chin-Hong said the polio vaccine has been shown to be safe and effective for decades. “You have to disentangle a new vaccine from this,” he said.
Chin-Hong said those infected may be asymptomatic and with the amount of travel between the Bay Area and New York “that’s an exclamation mark next to vaccination.”
The coronavirus era, he added, has amplified that exclamation mark.
He said pandemic stay-at-home orders in the Bay Area and elsewhere have likely delayed some children from getting polio vaccines. He also worries that “widespread hesitancy about (COVID-19) vaccines…has spread to other vaccines.” And although California has a strong mandate for children to be vaccinated against polio to attend school, some homeschooled students may have been slow to get vaccinated, Chin-Hong said.
He and Swartzberg pointed out that even given those concerns, the risk in California is extremely low.
“If you’re fully vaccinated, the vaccine works so well that you don’t have to worry, regardless of your age,” Swartzberg said. “For the general public who are fully vaccinated, there is no concern.”
Chase DiFeliciantonio is a writer for the San Francisco Chronicle. E-mail: chase.difeliciantonio@sfchronicle.com Twitter: @ChaseDiFelice