Polio Rises Again

A virus we thought vanquished in the US has a Phenix moment

It seems odd to be starting an update with a virus other than COVID. How quickly the once, all encompassing and paramount, transforms into the mundane, and intrudes less on our consciousness. Without any dramatic change in numbers, COVID is morphing into viral background noise—at least for those not hospitalized. Polio has just been found in the waste water stream of another New York county. Sullivan county abuts Orange, and it appears the virus has established community transmission there, as well as in Rockland and New York City. Thankfully only one case of paralytic disease has occurred so far, but I’m afraid luck is not destined to prevail. This week’s MMWR provides a summary of the CDC investigation thus far into the current polio outbreak, but the spread into Sullivan county is not included.

Public Health Response to a Case of Paralytic Poliomyelitis in an Unvaccinated Person and Detection of Poliovirus in Wastewater — New York, June–August 2022

Weekly / August 19, 2022 / 71(33);1065-1068

As previously discussed, all the circulating polio virus is Sabin type 2 vaccine derived and not wild type polio. 8% of 260 county waste water samples from June, July and August have been positive for the exact same virus, and a sample from April also was positive. Both the inactivated Salk vaccine (given exclusively in the US since 2000) and the live Sabin vaccine are highly effective, 99%, in preventing paralytic disease. If you are vaccinated and immunocompetent, you won’t develop symptomatic polio. Community transmission can continue however once a vaccine derived revertant virus is introduced, because the inactivated vaccine does not induce local immunity in the intestinal tract. While protected from paralysis, vaccinated people can acquire asymptomatic infection and shed the virus in stool. There is thus the potential for both the unvaccinated and the vaccinated to amplify the spread of the virus. Genomic sequencing of these waste water viral isolates shows they differ by 10 base pairs. Based on the polio’s usual rate of mutation, CDC scientists are estimating that this vaccine derived strain may have been circulating for as much as a year. Routine waste water testing for pathogens should become a permanent adjunct to the Public Health armamentarium, and we should be testing now for polio virus in the waste water across the country. Areas with lower vaccine coverage should be prioritized for monitoring and vaccination campaigns. Although overall vaccination rates are high in the US at 92% for 24 month olds, there are locations around the country where vaccination rates are as low as 37%. While we are not looking at any possibility of a return to the polio epidemics of the yesteryear, it’s clear that continued wide community circulation of the virus will cause further devastating cases of paralysis. Worldwide, 90% of paralytic polio cases in recent years have been due to vaccine derived virus, and in my opinion it’s well passed time to abandoned the use of the live vaccine. The argument is made that the oral vaccine is so much easier to give in third world settings. Well it just so happens that Public Health authorities are also trying to vaccinate the same children against measles, mumps, tetanus, diphtheria and Hepatitis B, all of which require an injection. For some comparison, there were over 9 million measles cases worldwide in 2018 and 142,000 deaths. Only 175 wild type polio cases occurred in two countries in 2018, but 960 cases of vaccine strain disease around the world. Since natural polio was eradicated in Africa, all cases of polio on the continent have been due to the live vaccine, and the same is true all over the world, except for Pakistan and Afghanistan. The Sabin vaccine had it’s place, allowing the eradication of wild type polio in places like India, where it was thought that feat might be impossible, but the situation is different today and requires re-evaluation.

The news cycle for Paxlovid relapses continues unabated with Jill Biden joining the ranks. Supporting my view that the drug fulfills it’s role in preventing severe disease and death in the vulnerable is the following study out of Israel.

Nirmatrelvir Use and Severe Covid-19 Outcomes during the Omicron Surge August 24, 2022

DOI: 10.1056/NEJMoa2204919

For the over 65 yo age group, Paxlovid treatment reduced hospitalization from 59 cases/100,000 to 14.7/100k, with a similar reduction in death. The most important finding here is that Paxlovid treatment in this age group was effective in vaccinated people during the Omicron era. The benefit is not as dramatic as seen during the original Pfizer trial in unvaccinated people, but still very substantial. 97% of people completed their 5 day course of treatment, so Paxlovid mouth is not stopping most people. It’s possible the bad taste in Biden’s and Fauci’s mouth was due to other factors. It has not been possible to demonstrate a benefit in younger people and Pfizer has abandoned that effort. On the other hand, it is reasonable to assume that a few younger people with very significant risk factors for severe disease might benefit.

Since the beginning of the Pandemic there has been a huge effort to find effective COVID treatment in repurposed drugs available off the shelf. That’s a normal human reaction to a situation where a deadly disease has no readily apparent treatment. In prior times that would take the form of this or that herb, blood letting, fumigation or incantations. In the modern era it took the somewhat more scientific approach of looking for compounds which had some identifiable effect on viral replication in tissue cultures, or another plausible but untested line of evidence and inference. Doctors from all over the world succumbed to the enticement of believing that the therapy they administered in good faith was curing their patients. This is extraordinarily easy to believe when the vast majority of people are destined to get better no matter what. There were testimonials and observational studies galore suggesting that hydroxychloroquine, ivermectin or fluvoxamine were effective in preventing progression of disease. It’s not hard to find analogous situations in the not too distant past. Some of us will remember Act-Up HIV activists demonstrating and accusing the FDA of murder because they wouldn’t approve Kemron, a drug developed and produced by the Nigerian government as an (ultimately worthless) treatment for AIDS. Americans going to Mexico (Steve McQueen) for treatment of their cancer with Laetrile, a compound with no therapeutic benefit, and side effects similar to cyanide poisoning. This is why, in the best case, modern medicine employs double blind randomized controlled studies. Referenced next is a randomized controlled trial published in the NEJM showing no benefit from Ivermectin, Fluvoxamine and Metformin. Although there was a suggestion of benefit in a pre-specified secondary end point for Metformin, I wouldn’t bet heavily this will be confirmed by further study. On the other hand look for Metformin sales to spike up.

Randomized Trial of Metformin, Ivermectin, and Fluvoxamine for Covid-19 N Engl J Med 2022; 387:599-610
DOI: 10.1056/NEJMoa2201662

Next up is the Monkeypox. Hopefully everyone had an opportunity to put in their suggestion on the WHO website for a new name. US cases stand at 17,500 with 0 deaths, but some cases of severe disease so far. Bucking the trend of wishing to avoid stigma, I suggested Kocherpox; harking back to the days when immortality outweighed shame. This virus is neurotrophic to some extent, and in addition to the possibility of brain or spinal chord disease during the the acute phase, there is also the possibility of delayed, post infectious neurological syndromes due to the immune response damaging tissues. In order to combat the shortage of vaccine, the government has adopted a strategy of giving 1/5 the originally designed dose via the intradermal route, instead of the approved intramuscular injection. I hope they are planning to collect data both on the magnitude and duration of the antibody response in this large group of test subjects, as well as the efficacy in disease prevention. Given what we learned last week about the occurrence of asymptomatic infection in the rectum, I would also hope they are planning to conduct surveys to see if the vaccine has any effect on preventing this. My guess is no. By Rachel Walensky’s admission last week, the score card for COVID and Monkeypox is Virus 2 and CDC 0, so this would be a good time to play catch up.

Finally a few quick thoughts about Influenza, a nice comfortable, old fashion virus we all know well. Two Pandemic years of masking (yes Virginia it does reduce the spread of respiratory viruses) and social distancing made it look like Influenza was a thing of the past. Well the flu has other ideas, and there is good evidence that it will be back in earnest this year. The winter flu season in Australia has been particularly bad and cases are being seen now in the US. I generally have waited a bit, until October say, to get a flu shot, hoping to have good antibody levels persisting into the later part of the season. This year I think it would be a good idea to get your shot earlier. Our collective immunity to Influenza is much lower than most normal years, and the Pandemic has caused all sorts of disruptions in the normal seasonality of a variety of viral illnesses. More importantly, I think Influenza may be tired of letting COVID get all the PR coverage.

Hit the like button if you find the site interesting, and please share with at least one other person.