Safety of incidental exposure to the novel oral poliovirus vaccine type 2 in pregnancy: A longitudinal observational study in Mozambique, 2022-2023.

BACKGROUND: To minimize the risk of vaccine-derived poliovirus emergences, the novel oral poliovirus vaccine type 2 (nOPV2), was bioengineered to have increased genetic stability compared to Sabin OPV and recommended for outbreak response Emergency Use Listing by WHO. Although pregnant women are not a target population for this vaccine, a theoretical risk of incidental exposure exists via pharyngeal or faecal shedding from vaccinated children in the household or close community. METHODS: This was an observational study of pregnant women conducted in Nampula (exposed cohort) and Maputo (non-exposed cohort) in Mozambique from August 2022 to June 2023. Two nOPV2 campaigns were conducted in Nampula and none in Maputo. Women were followed-up during routine prenatal consultation, delivery, and 28-day neonate visits for obstetric anomalies and pregnancy outcomes. Sociodemographic, medical, and obstetric history was captured. RESULTS: Three hundred twenty-six pregnant women were enrolled from Nampula and 940 from Maputo City. Stillbirth prevalence (2·3% vs 1·6%, p = 0·438), low birth weight (8·9% vs 8·2%, p = 0·989), congenital anomalies (1 % vs 0·5%, p = 0·454), neonatal death (2·3% vs 1·6%, p = 0·08), and maternal death (0 % vs 0·2%, p = 0·978) did not differ amongst exposed and non-exposed cohorts. There was an increased rate of pre-term delivery in the exposed cohort (18·4% vs 11·0%, p = 0·011). CONCLUSION: We did not observe an increased frequency of adverse pregnancy outcomes due to passive nOPV2 exposure. A higher frequency of preterm delivery needs to be further investigated. The data reported herein support the continued use of nOPV2 for poliovirus outbreak response and full licensure of the vaccine.

Safety of incidental exposure to the novel oral poliovirus vaccine type 2 in pregnancy: A longitudinal observational study in Mozambique, 2022-2023

To minimize the risk of vaccine-derived poliovirus emergences, the novel oral poliovirus vaccine type 2 (nOPV2), was bioengineered to have increased genetic stability compared to Sabin OPV and recommended for outbreak response Emergency Use Listing by WHO. Although pregnant women are not a target population for this vaccine, a theoretical risk of incidental exposure exists via pharyngeal or faecal shedding from vaccinated children in the household or close community. Methods: This was an observational study of pregnant women conducted in Nampula (exposed cohort) and Maputo (non-exposed cohort) in Mozambique from August 2022 to June 2023. Two nOPV2 campaigns were conducted in Nampula and none in Maputo. Women were followed-up during routine prenatal consultation, delivery, and 28-day neonate visits for obstetric anomalies and pregnancy outcomes. Sociodemographic, medical, and obstetric history was captured. Results: Three hundred twenty-six pregnant women were enrolled from Nampula and 940 from Maputo City. Stillbirth prevalence (2·3% vs 1·6%, p = 0·438), low birth weight (8·9% vs 8·2%, p = 0·989), congenital anomalies (1 % vs 0·5%, p = 0·454), neonatal death (2·3% vs 1·6%, p = 0·08), and maternal death (0 % vs 0·2%, p = 0·978) did not differ amongst exposed and non-exposed cohorts. There was an increased rate of pre-term delivery in the exposed cohort (18·4% vs 11·0%, p = 0·011). Conclusion: We did not observe an increased frequency of adverse pregnancy outcomes due to passive nOPV2 exposure. A higher frequency of preterm delivery needs to be further investigated. The data reported herein support the continued use of nOPV2 for poliovirus outbreak response and full licensure of the vaccine.

Effects of the COVID-19 pandemic on maternal and perinatal health service utilisation and outcomes in Mozambique: an interrupted time series analysis.

OBJECTIVES: To measure the effects of the COVID-19 pandemic on maternal and perinatal health services and outcomes in Mozambique. DESIGN: This is an observational study analysing routine service delivery data using interrupted time series analysis. We used 43 months of district-level panel data with April 2020 as the point of interruption, adjusting for seasonality and population growth to analyse service utilisation outcomes. SETTING: The 222 public health facilities in Nampula Province, Mozambique, from January 2018 to July 2021. OUTCOME MEASURES: The change in the number of antenatal care (ANC) visits and facility deliveries, and the change in the rate of adverse birth outcomes at pandemic onset and over time compared with expected levels and trends, respectively. RESULTS: There were no significant disruptions to ANC at pandemic onset. Following this, there was a significant monthly increase of 29.8 (18.2-41.4) first ANC visits and 11.3 (5.5-17.2) ANC visits within the first trimester per district above prepandemic trends. There was no significant change in the number of fourth ANC visits completed. At the onset of COVID-19, districts experienced a significant decrease of 71.1 (-110.5 to -31.7) facility deliveries, but the rate then increased significantly above prepandemic trends. There was no significant increase in any adverse birth outcomes during the pandemic. Conversely, districts observed a significant monthly decrease of 5.3 uterine rupture cases (-9.9 to -0.6) and 19.2 stillbirths (-33.83 to -4.58) per 100 000 facility deliveries below prepandemic trends. There was a significant drop of 23.5 cases of neonatal sepsis/100 000 facility deliveries per district at pandemic onset. CONCLUSION: Despite pandemic interference, Nampula Province saw no disruptions to ANC, only temporary disruptions to facility deliveries and no increases in adverse birth outcomes. ANC visits surprisingly increased, and the rates of uterine rupture, stillbirth and neonatal sepsis decreased, suggesting that Nampula Province may offer insights about health system resilience.

Oral cholera vaccine coverage during a preventive door-to-door mass vaccination campaign in Nampula, Mozambique.

BACKGROUND: In addition to improving water, sanitation and hygiene (WASH) measures and optimal case management, the introduction of Oral cholera vaccine (OCV) is a complementary strategy for cholera prevention and control for vulnerable population groups. In October 2016, the Mozambique Ministry of Health implemented a mass vaccination campaign using a two-dose regimen of the Shanchol™ OCV in six high-risk neighborhoods of Nampula city, in Northern Mozambique. Overall 193,403 people were targeted by the campaign, which used a door-to-door strategy. During campaign follow-up, a population survey was conducted to assess: (1) OCV coverage; (2) frequency of adverse events following immunization; (3) vaccine acceptability and (4) reasons for non-vaccination. METHODOLOGY/PRINCIPAL FINDINGS: In the absence of a household listing and clear administrative neighborhood delimitations, we used geospatial technology to select households from satellite images and used the support of community leaders. One person per household was randomly selected for interview. In total, 636 individuals were enrolled in the survey. The overall vaccination coverage with at least one dose (including card and oral reporting) was 69.5% (95%CI: 51.2-88.2) and the two-dose coverage was 51.2% (95%CI: 37.9-64.3). The campaign was well accepted. Among the 185 non-vaccinated individuals, 83 (44.6%) did not take the vaccine because they were absent when the vaccination team visited their houses. Among the 451 vaccinated individuals, 47 (10%) reported minor and non-specific complaints, and 78 (17.3%) mentioned they did not receive any information before the campaign. CONCLUSIONS/SIGNIFICANCE: In spite of overall coverage being slightly lower than expected, the use of a mobile door-to-door strategy remains a viable option even in densely-populated urban settings. Our results suggest that campaigns can be successfully implemented and well accepted in Mozambique in non-emergency contexts in order to prevent cholera outbreaks. These findings are encouraging and complement the previous Mozambican experience related to OCV.