Greetings Polio Warriors:

Wild Poliovirus - I can say ONCE AGAIN…NO NEW CASES this last week .

TWO HUNDRED AND TWO - The number of days since the last case of the wild poliovirus Type 1 occurred in Afghanistan.

ONE HUNDRED AND SEVENTY-FIVE - The number of days since the last case of the wild poliovirus Type 1 occurred in Pakistan.

TWO - The total number of cases of the wild poliovirus Type 1 that have occurred in the world since New Years Day.

EIGHTY-SEVEN - The number of cases of the wild poliovirus Type 1 that occurred in 2020 on this date.

Last week marks the TWENTY-FIFTH WEEK IN A ROW with no newreported cases. There was also no positive environmental samples this pastweek as well, for the second week in a row.

Vaccine-Derived Polio - Unfortunately we had a major increase in the number of cases of Vaccine-Derived Polio (cVDPV) reported last week. 24 cases were reported, however 10 of those cases occurred in Ethiopia last year (2020), but are only now being reported. The 14 cases that did occur in 2021 were 9 in Nigeria, 2 in Madagascar and one each in Liberia, Senegal and South Sudan. 6 Positive environmental samples also occurred this last week, the same as the week before. There were 5 in Nigeria,and one in Ethiopia.
I must admit that the relatively high number of cases and positive environmental samples that occurred in Nigeria is concerning. Last week we reported 11 countries now using the new novel oral polio vaccine Type 2 (nOPV2) with 21 others in the pipeline for approval, and I believe Nigeria was one of the first countries to start using the new vaccine near the end of March. I do know that in order to qualify to use the new novel oral polio vaccine, a country has to have 12 weeks between the last use of the original Sabin oral vaccine and the new novel oral vaccine. I was told that because this vaccine is still under study, and operating under an Emergency Use Listing, they want to make sure that initial test results are not skewed because of any after-effects of the old Sabin Vaccine. That’s why the 12 weeks of no vaccination activity. Now this is purely speculationon my part, but It could be that these relatively high number of cases and positive environmental samples are a result of not being able to vaccinate children for a period of 12 weeks prior to the end of March when they were able to finally start vaccinating with the new novel oral vaccine. Again, just pure speculation from a lay person, so please take that into consideration when pondering this comment.