Wastewater Testing and Detection of Poliovirus Type 2 Genetically Linked to Virus Isolated from a Paralytic Polio Case - New York, March 9-October 11, 2022

In July 2022, a case of paralytic poliomyelitis resulting from infection with vaccine-derived poliovirus (VDPV) type 2 (VDPV2)§ was confirmed in an unvaccinated adult resident of Rockland County, New York (1). As of August 10, 2022, poliovirus type 2 (PV2)¶ genetically linked to this VDPV2 had been detected in wastewater** in Rockland County and neighboring Orange County (1). This report describes the results of additional poliovirus testing of wastewater samples collected during March 9-October 11, 2022, and tested as of October 20, 2022, from 48 sewersheds (the community area served by a wastewater collection system) serving parts of Rockland County and 12 surrounding counties. Among 1,076 wastewater samples collected, 89 (8.3%) from 10 sewersheds tested positive for PV2. As part of a broad epidemiologic investigation, wastewater testing can provide information about where poliovirus might be circulating in a community in which a paralytic case has been identified; however, the most important public health actions for preventing paralytic poliomyelitis in the United States remain ongoing case detection through national acute flaccid myelitis (AFM) surveillance†† and improving vaccination coverage in undervaccinated communities. Although most persons in the United States are sufficiently immunized, unvaccinated or undervaccinated persons living or working in Kings, Orange, Queens, Rockland, or Sullivan counties, New York should complete the polio vaccination series as soon as possible.

LB16. The Role of Adults in the Measles Outbreak in New York State Outside of New York City, 2018–2019

Background

The United States is experiencing the largest measles outbreak since elimination was declared in 2000, with the majority of cases in NYS reported in undervaccinated communities. The objective of this evaluation was to describe adult measles cases in the NYS measles outbreak outside of New York City (NYC).

Methods

We included all confirmed cases aged ≥18 years in NYS residents (excluding NYC) during October 1, 2018–July 25, 2019 that met the CSTE measles case definition. We defined measles cases attributable to adults as the sum of measles cases among adults and children who contracted disease directly from adults.

Results

Among 371 confirmed measles cases, the median age was 5.5 years (range: 1 day to 64 years); 79 (21%) were in adults, 4 (5%) of whom were born before 1957 (3 unvaccinated and 1 with unknown vaccine status). Among the 75 cases born during or after 1957, 65 (87%) were unvaccinated or had unknown vaccine status, while 3 had one dose and 7 had 2 doses of measles vaccine. Notably, 5 of 11 internationally imported measles cases were adults, and all were unvaccinated or had unknown vaccine status. During the first month of the outbreak, 26 of the 51 (51%) cases were attributable to adults; of the 26, 15 (58%) were in adults and 11 (42%) were in children who acquired infection from adults (Figure 3).

Conclusion

The majority of measles cases occurred in unvaccinated children emphasizing the importance of ongoing and focused efforts on pediatric vaccination. However, measles cases in unvaccinated adults played an important role in both importations and disease transmission early in the outbreak. These data strongly support current recommendations of 1 dose of measles, mumps, rubella vaccine (MMR) for most adults and 2 doses of MMR for adults traveling internationally and at high-risk such as those in outbreak areas, as determined by local/state public health.

Disclosures

Kirsten St. George, MAppSc, PhD, Akonni Biosystems (Other Financial or Material Support), ThermoFisher (Grant/Research Support), Zeptometrix (Other Financial or Material Support, royalty generating collaborative agreement). .

LB15. Measles Outbreak in New York State (NYS) Outside of New York City, 2018–2019

Background

The United States is experiencing one of the largest and longest measles outbreaks since elimination was declared in 2000 and is at risk of losing this status. Most cases occurring in NYS were reported in undervaccinated communities.

Methods

We included all confirmed NYS measles cases (excluding NYC) from outbreak counties from October 1, 2018 to July 25, 2019. We used the CSTE measles case definition requiring an acute febrile rash illness and either laboratory confirmation or direct epidemiologic linkage to a lab-confirmed case. For each case, demographic and clinical characteristics were obtained. A medical record review was completed for those reported to have an encounter at a hospital, emergency department, or urgent care center.

Results

There were 371 cases of measles reported, including 11 internationally imported cases. Most occurred in Rockland county (n = 283); followed by Orange (n = 55), Westchester (n = 18), Sullivan (n = 14) and Greene (n = 1) (Figures 1 and 2). The median age was 5.5 years; 79% of all cases occurred among children younger than 18 years of age (Figure 3). Most cases (79%) had not received any doses of measles vaccine. Of the 371 cases, 263 (71%) were children who had received 0 doses of measles, mumps, rubella vaccine (MMR), 218 (83%) of whom were over 1 year of age (Table 1). There have been no deaths or documented cases of encephalitis. Twenty-eight (8%) patients were diagnosed with pneumonia and 25 (7%) patients were hospitalized. Among 17 hospitalized children, 5 (29%) were admitted to the intensive care unit (ICU) (ages 1 day to 7 years). There were two preterm births at 34 and 25 weeks gestation to women with measles while pregnant. During October 1, 2018–July 31, 2019, providers in outbreak counties vaccinated 72,465 individuals with MMR, a 46% increase from the same period the year prior.

Conclusion

Unvaccinated children were identified as the largest group affected and experienced severe complications; nearly 30% of hospitalized children were admitted to an ICU. These data support the critical need for continued education and outreach on the risks of measles and the value of vaccination to prevent continued circulation in undervaccinated communities and potential further cases of severe disease.

Disclosures

Kirsten St. George, MAppSc, PhD, Akonni Biosystems (Other Financial or Material Support), ThermoFisher (Grant/Research Support), Zeptometrix (Other Financial or Material Support, royalty generating collaborative agreement); others, no disclosures reported..

Abortive initiation by bacteriophage T3 and T7 RNA polymerases under conditions of limiting substrate

Initiation of RNA synthesis by the phage polymerases is abortive if the concentration of pyrimidine triphosphates is limiting. Under abortive initiation conditions the polymerases repeatedly initiate transcription but produce ribooligonucleotides that terminate just prior to the first occurrence of the limiting substrate. Abortive initiation is most severe if the limiting substrate occurs within the first 8-12 nucleotides of the nascent RNA chain and is particularly evident when UMP is limiting. The formation of stable elongation complexes (as determined by gel retardation experiments) occurs after the synthesis of an RNA product 8-12 nucleotides in length.