Rapid rise in COVID-19 among young people in England - learning for the future.

OBJECTIVES: We determined the age and sociodemographic distribution of COVID-19 cases between January and September 2020 to identify the group with the highest incidence rates at the beginning of the second wave in England. STUDY DESIGN: We undertook a retrospective cohort study design. METHODS: SARS-CoV-2 cases in England were linked with area-level socio-economic status indicators using quintiles of the Index of Multiple Deprivation (IMD). Age-specific incidence rates were stratified by IMD quintile to further assess rates by area-level socio-economic status. RESULTS: Between July and September 2020, SARS-CoV-2 incidence rates were highest amongst those aged 18-21 years, reaching rates of 213.9 (18-19 years) and 143.2 (20-21 years) per 100,000 population by week ending 21 September 2022. Stratification of incidence rates by IMD quintile evidenced that despite high rates observed in the most deprived areas of England amongst the very young and older age groups, the highest rates were observed in the most affluent areas of England amongst the 18- to 21-year-olds. CONCLUSIONS: The reversal of sociodemographic trend in COVID-19 cases in England for those aged 18-21 years at the end of the summer of 2020 and beginning of the second wave showed a novel pattern of COVID-19 risk. For other age groups, the rates remained highest for those from more deprived areas, which highlighted persisting inequalities. Combined, this demonstrates the need to reinforce awareness of COVID-19 risk for young people, particularly given the late inclusion of the 16-17 years age group for vaccination administration, as well as continued efforts to reduce the impact of COVID-19 on vulnerable populations.

Hospitalisation and mortality risk of SARS-COV-2 variant omicron sub-lineage BA.2 compared to BA.1 in England.

The Omicron variant of SARS-CoV-2 became the globally dominant variant in early 2022. A sub-lineage of the Omicron variant (BA.2) was identified in England in January 2022. Here, we investigated hospitalisation and mortality risks of COVID-19 cases with the Omicron sub-lineage BA.2 (n = 258,875) compared to BA.1 (n = 984,337) in a large cohort study in England. We estimated the risk of hospital attendance, hospital admission or death using multivariable stratified proportional hazards regression models. After adjustment for confounders, BA.2 cases had lower or similar risks of death (HR = 0.80, 95% CI 0.71-0.90), hospital admission (HR = 0.88, 95% CI 0.83-0.94) and any hospital attendance (HR = 0.98, 95% CI 0.95-1.01). These findings that the risk of severe outcomes following infection with BA.2 SARS-CoV-2 was slightly lower or equivalent to the BA.1 sub-lineage can inform public health strategies in countries where BA.2 is spreading.

Six-year experience of detection and investigation of possible Middle East Respiratory Syndrome coronavirus cases, England, 2012-2018.

OBJECTIVES: Surveillance for Middle East Respiratory Syndrome (MERS) has been undertaken in the UK since September 2012. This study describes the surveillance outcomes in England from 2012 to 2018. STUDY DESIGN: This was a descriptive study using surveillance data. METHODS: Local health protection teams in England report possible MERS cases to the National Infection Service with clinical and laboratory data. RESULTS: A total of 1301 possible MERS cases were identified in the study period. Five cases were laboratory-confirmed MERS. The majority of cases had travelled to Saudi Arabia (56.7%) and United Arab Emirates (25.9%). Fifty-four percent of cases were men and 43.7% were women. The majority of cases (65.1%) were aged 45 years or older. The number of tests increased in the period after Hajj each year. Laboratory-confirmed alternative diagnoses were available for 513 (39.4%) cases; influenza was the most common virus detected (n = 255, 52.4%). CONCLUSIONS: Our study highlights the importance of differential diagnosis of influenza and other respiratory pathogens and early influenza antiviral treatment.

European all-cause excess and influenza-attributable mortality in the 2017/18 season: should the burden of influenza B be reconsidered?

OBJECTIVES: Weekly monitoring of European all-cause excess mortality, the EuroMOMO network, observed high excess mortality during the influenza B/Yamagata dominated 2017/18 winter season, especially among elderly. We describe all-cause excess and influenza-attributable mortality during the season 2017/18 in Europe. METHODS: Based on weekly reporting of mortality from 24 European countries or sub-national regions, representing 60% of the European population excluding the Russian and Turkish parts of Europe, we estimated age stratified all-cause excess morality using the EuroMOMO model. In addition, age stratified all-cause influenza-attributable mortality was estimated using the FluMOMO algorithm, incorporating influenza activity based on clinical and virological surveillance data, and adjusting for extreme temperatures. RESULTS: Excess mortality was mainly attributable to influenza activity from December 2017 to April 2018, but also due to exceptionally low temperatures in February-March 2018. The pattern and extent of mortality excess was similar to the previous A(H3N2) dominated seasons, 2014/15 and 2016/17. The 2017/18 overall all-cause influenza-attributable mortality was estimated to be 25.4 (95%CI 25.0-25.8) per 100,000 population; 118.2 (116.4-119.9) for persons aged 65. Extending to the European population this translates into over-all 152,000 deaths. CONCLUSIONS: The high mortality among elderly was unexpected in an influenza B dominated season, which commonly are considered to cause mild illness, mainly among children. Even though A(H3N2) also circulated in the 2017/18 season and may have contributed to the excess mortality among the elderly, the common perception of influenza B only having a modest impact on excess mortality in the older population may need to be reconsidered.

Significant spike in excess mortality in England in winter 2014/15 - influenza the likely culprit.

Significant increases in excess all-cause mortality, particularly in the elderly, were observed during the winter of 2014/15 in England. With influenza A(H3N2) the dominant circulating influenza A subtype, this paper determines the contribution of influenza to this excess controlling for weather. A standardised multivariable Poisson regression model was employed with weekly all-cause deaths the dependent variable for the period 2008-2015. Adjusting for extreme temperature, a total of 26 542 (95% CI 25 301-27 804) deaths in 65+ and 1942 (95% CI 1834-2052) in 15-64-year-olds were associated with influenza from week 40, 2014 to week 20, 2015. This is compatible with the circulation of influenza A(H3N2). It is the largest estimated number of influenza-related deaths in England since prior to 2008/09. The findings highlight the potential health impact of influenza and the important role of the annual influenza vaccination programme that is required to protect the population including the elderly, who are vulnerable to a severe outcome.

Population-level factors predicting variation in influenza vaccine uptake among adults and young children in England, 2015/16 and 2016/17.

England's influenza vaccination programme targets persons with clinical risk factors, pregnant women, those aged 65 years and older and children. Low vaccine uptake amongst primary school children was previously found to be significantly associated with increasing deprivation, Black or Minority Ethnic (BME) and certain religions. It is unknown whether these population predictors are associated with vaccine uptake in other groups. GP level data for target groups during the 2015/16 and 2016/17 seasons were linearly regressed against various factors to determine potential predictors associated with variation in uptake. Adjusted uptake for 2-4 year olds during both seasons was more than 11% lower in the most deprived decile and more than 3% lower in 34%+ BME populations compared to the least deprived and non-BME populations. Pregnant women in deprived areas had significantly lower vaccine uptake than in non-deprived areas. Patients 16-64 years old at risk showed no significant variation in uptake by deprivation, whereas patients 65 years and older had more than 3% higher vaccine uptake in the least deprived populations than the most deprived populations. Areas with the highest Muslim and BME populations had a significantly higher vaccine uptake among patients ages 16 to under 65 years old in a clinical risk group than non-Muslim and non-BME populations during both seasons. Population-factors have different effects on vaccine uptake for the various target groups. These findings support segmenting public health activities to improve vaccine uptake and reduce inequalities.