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Developing a serocorrelate of protection against invasive group B streptococcus disease in pregnant women: a feasibility study.
BACKGROUND: Group B streptococcus is the leading cause of infection in infants. Currently, intrapartum antibiotic prophylaxis is the major strategy to prevent invasive group B streptococcus disease. However, intrapartum antibiotic prophylaxis does not prevent maternal sepsis, premature births, stillbirths or late-onset disease. Maternal vaccination may offer an alternative strategy. Multivalent polysaccharide protein conjugate vaccine development is under way and a serocorrelate of protection is needed to expedite vaccine licensure. OBJECTIVES: The ultimate aim of this work is to determine the correlate of protection against the major group B streptococcus disease-causing serotypes in infants in the UK. The aim of this feasibility study is to test key operational aspects of the study design. DESIGN: Prospective cohort study of pregnant women and their infants in a 6-month period (1 July to 31 December 2018). SETTING: Five secondary and tertiary hospitals from London and South England. National iGBS disease surveillance was conducted in all trusts in England and Wales. PARTICIPANTS: Pregnant women aged ≥ 18 years who were delivering at one of the selected hospitals and who provided consent during the study period. There were no exclusion criteria. INTERVENTIONS: No interventions were performed. MAIN OUTCOME MEASURES: (1) To test the feasibility of collecting serum at delivery from a large cohort of pregnant women. (2) To test the key operational aspects for a proposed large serocorrelates study. (3) To test the feasibility of collecting samples from those with invasive group B streptococcus. RESULTS: A total of 1823 women were recruited during the study period. Overall, 85% of serum samples were collected at three sites collecting only cord blood. At the two sites collecting maternal, cord and infant blood samples, the collection rate was 60%. A total of 614 women were screened for group B streptococcus with a colonisation rate of 22% (serotype distribution: 30% III, 25% Ia, 16% II, 14% Ib, 14% V and 1% IV). A blood sample was collected from 34 infants who were born to colonised women. Maternal and infant blood and the bacterial isolates for 15 newborns who developed invasive group B streptococcal disease during the study period were collected (serotype distribution: 29% III, 29% II, 21% Ia, 7% Ib, 7% IV and 7% V). LIMITATIONS: Recruitment and sample collection were dependent on the presence of research midwives rather than the whole clinical team. In addition, individualised consent limited the number of women who could be approached each day, and site set-up for the national surveillance study and the limited time period of this feasibility study limited recruitment of all eligible participants. CONCLUSIONS: We have verified the feasibility of collecting and processing rectovaginal swabs and blood samples in pregnant women, as well as samples from those with invasive group B streptococcal disease. We have made recommendations for the recruitment of cases within the proposed GBS3 study and for controls both within GBS3 and as an extension of this feasibility study. FUTURE WORK: A large case-control study comparing specific immunoglobulin G levels in mothers whose infants develop invasive group B streptococcal disease with those in colonised mothers whose infants do not develop invasive group B streptococcal disease is recommended. TRIAL REGISTRATION: Current Controlled Trials ISRCTN49326091; IRAS project identification number 246149/REC reference number 18/WM/0147. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 67. See the NIHR Journals Library website for further project information
Seasonality and the effects of weather on Campylobacter infections
Background Campylobacteriosis is a major public health concern. The weather factors that influence spatial and seasonal distributions are not fully understood. Methods To investigate the impacts of temperature and rainfall on Campylobacter infections in England and Wales, cases of Campylobacter were linked to local temperature and rainfall at laboratory postcodes in the 30 days before the specimen date. Methods for investigation included a comparative conditional incidence, wavelet, clustering, and time series analyses. Results The increase of Campylobacter infections in the late spring was significantly linked to temperature two weeks before, with an increase in conditional incidence of 0.175 cases per 100,000 per week for weeks 17 to 24; the relationship to temperature was not linear. Generalized structural time series model revealed that changes in temperature accounted for 33.3% of the expected cases of Campylobacteriosis, with an indication of the direction and relevant temperature range. Wavelet analysis showed a strong annual cycle with additional harmonics at four and six months. Cluster analysis showed three clusters of seasonality with geographic similarities representing metropolitan, rural, and other areas. Conclusions The association of Campylobacteriosis with temperature is likely to be indirect. High-resolution spatial temporal linkage of weather parameters and cases is important in improving weather associations with infectious diseases. The primary driver of Campylobacter incidence remains to be determined; other avenues, such as insect contamination of chicken flocks through poor biosecurity should be explored
Seasonality and the effects of weather on Campylobacter infections
This is the final version. Available on open access from BMC via the DOI in this recordAvailability of data and materials:
The datasets on MEDMI are described at https://www.data-mashup.org.uk/data/data-library/ and include the SGSS infectious disease dataset. Permissions are required to access these datasets and users require an account to be set up as described at https://www.data-mashup.org.uk/data/accessing-data/.BACKGROUND: Campylobacteriosis is a major public health concern. The weather factors that influence spatial and seasonal distributions are not fully understood. METHODS: To investigate the impacts of temperature and rainfall on Campylobacter infections in England and Wales, cases of Campylobacter were linked to local temperature and rainfall at laboratory postcodes in the 30 days before the specimen date. Methods for investigation included a comparative conditional incidence, wavelet, clustering, and time series analyses. RESULTS: The increase of Campylobacter infections in the late spring was significantly linked to temperature two weeks before, with an increase in conditional incidence of 0.175 cases per 100,000 per week for weeks 17 to 24; the relationship to temperature was not linear. Generalized structural time series model revealed that changes in temperature accounted for 33.3% of the expected cases of Campylobacteriosis, with an indication of the direction and relevant temperature range. Wavelet analysis showed a strong annual cycle with additional harmonics at four and six months. Cluster analysis showed three clusters of seasonality with geographic similarities representing metropolitan, rural, and other areas. CONCLUSIONS: The association of Campylobacteriosis with temperature is likely to be indirect. High-resolution spatial temporal linkage of weather parameters and cases is important in improving weather associations with infectious diseases. The primary driver of Campylobacter incidence remains to be determined; other avenues, such as insect contamination of chicken flocks through poor biosecurity should be explored
Interim 2017/18 influenza seasonal vaccine effectiveness: Combined results from five European studies
Between September 2017 and February 2018, influenza A(H1N1)pdm09, A(H3N2) and B viruses (mainly B/Yamagata, not included in 2017/18 trivalent vaccines) co-circulated in Europe. Interim results from five European studies indicate that, in all age groups, 2017/18 influenza vaccine effectiveness was 25 to 52% against any influenza, 55 to 68% against influenza A(H1N1)pdm09, -42 to 7% against influenza A(H3N2) and 36 to 54% against influenza B. 2017/18 influenza vaccine should be promoted where influenza still circulates
Rapid increase in non-vaccine serotypes causing invasive pneumococcal disease in England and Wales, 2000-17: a prospective national observational cohort study.
BACKGROUND: Pneumococcal conjugate vaccines (PCVs) have substantially reduced the incidence of invasive pneumococcal disease caused by vaccine serotypes; however, replacement disease with non-PCV serotypes remains a concern. We describe the population effect of the seven-valent and 13-valent PCVs (PCV7 and PCV13) on invasive pneumococcal disease in England and Wales. METHODS: Using national invasive pneumococcal disease surveillance data for 2016/17, we compared incidence rate ratios (IRRs) against pre-PCV13 (2008/09-2009/10) and pre-PCV7 (2000/01-2005/06) baselines. We also estimated the number of invasive pneumococcal disease cases prevented since the introduction of PCVs. FINDINGS: In 2016/17, overall invasive pneumococcal disease incidence (9·87 cases per 100 000; 5450 cases) across all age groups was 37% lower (IRR 0·63, 95% CI 0·60-0·65) than pre-PCV7 incidence (14·79 per 100 000; 8167 cases) and 7% lower (0·93; 0·89-0·97) than pre-PCV13 incidence (10·13 per 100 000; 5595 cases). By 2016/17, PCV7-type invasive pneumococcal disease incidence across all age groups had decreased by 97% (0·24 per 100 000; 0·03, 0·02-0·04) compared with the pre-PCV7 period, whereas additional PCV13-type invasive pneumococcal disease decreased by 64% (1·66 per 100 000; 0·36, 0·32-0·40) since the introduction of PCV13. Invasive pneumococcal disease incidence due to non-PCV13 serotypes doubled (7·97 per 100 000; 1·97, 1·86-2·09) since the introduction of PCV7, and accelerated since 2013/14-especially serotypes 8, 12F, and 9N, which were responsible for more than 40% of invasive pneumococcal disease cases by 2016/17. Invasive pneumococcal disease incidence in children younger than 5 years remained stable since 2013/14, with nearly all replacement disease occurring in adults. We estimated 38 366 invasive pneumococcal disease cases were prevented in the 11 years since the introduction of PCV7. INTERPRETATION: Both PCV7 and PCV13 have had a major effect in reducing the burden of invasive pneumococcal disease in England and Wales; however, rapid increases in some non-PCV13 serotypes are compromising the benefits of the programme. FUNDING: Public Health England
Seasonality and the effects of weather on Campylobacter infections
Background: Campylobacteriosis is a major public health concern. The weather factors that influence spatial and seasonal distributions are not fully understood. Methods: To investigate the impacts of temperature and rainfall on Campylobacter infections in England and Wales, cases of Campylobacter were linked to local temperature and rainfall at laboratory postcodes in the 30 days before the specimen date. Methods for investigation included a comparative conditional incidence, wavelet, clustering, and time series analyses. Results: The increase of Campylobacter infections in the late spring was significantly linked to temperature two weeks before, with an increase in conditional incidence of 0.175 cases per 100,000 per week for weeks 17 to 24; the relationship to temperature was not linear. Generalized structural time series model revealed that changes in temperature accounted for 33.3% of the expected cases of Campylobacteriosis, with an indication of the direction and relevant temperature range. Wavelet analysis showed a strong annual cycle with additional harmonics at four and six months. Cluster analysis showed three clusters of seasonality with geographic similarities representing metropolitan, rural, and other areas. Conclusions: The association of Campylobacteriosis with temperature is likely to be indirect. High-resolution spatial temporal linkage of weather parameters and cases is important in improving weather associations with infectious diseases. The primary driver of Campylobacter incidence remains to be determined; other avenues, such as insect contamination of chicken flocks through poor biosecurity should be explored. © 2019 The Author(s)
End of season influenza vaccine effectiveness in adults and children in the United Kingdom in 2017/18
BackgroundIn the United Kingdom (UK), in recent influenza seasons, children are offered a quadrivalent live attenuated influenza vaccine (LAIV4), and eligible adults mainly trivalent inactivated vaccine (TIV).AimTo estimate the UK end-of-season 2017/18 adjusted vaccine effectiveness (aVE) and the seroprevalence in England of antibodies against influenza viruses cultured in eggs or tissue.MethodsThis observational study employed the test-negative case-control approach to estimate aVE in primary care. The population-based seroprevalence survey used residual age-stratified samples.ResultsInfluenza viruses A(H3N2) (particularly subgroup 3C.2a2) and B (mainly B/Yamagata/16/88-lineage, similar to the quadrivalent vaccine B-virus component but mismatched to TIV) dominated. All-age aVE was 15% (95% confidence interval (CI): -6.3 to 32) against all influenza; -16.4% (95% CI: -59.3 to 14.9) against A(H3N2); 24.7% (95% CI: 1.1 to 42.7) against B and 66.3% (95% CI: 33.4 to 82.9) against A(H1N1)pdm09. For 2-17 year olds, LAIV4 aVE was 26.9% (95% CI: -32.6 to 59.7) against all influenza; -75.5% (95% CI: -289.6 to 21) against A(H3N2); 60.8% (95% CI: 8.2 to 83.3) against B and 90.3% (95% CI: 16.4 to 98.9) against A(H1N1)pdm09. For ≥ 18 year olds, TIV aVE against influenza B was 1.9% (95% CI: -63.6 to 41.2). The 2017 seroprevalence of antibody recognising tissue-grown A(H3N2) virus was significantly lower than that recognising egg-grown virus in all groups except 15-24 year olds.ConclusionsOverall aVE was low driven by no effectiveness against A(H3N2) possibly related to vaccine virus egg-adaption and a new A(H3N2) subgroup emergence. The TIV was not effective against influenza B. LAIV4 against influenza B and A(H1N1)pdm09 was effective
End of season influenza vaccine effectiveness in adults and children in the United Kingdom in 2017/18
BackgroundIn the United Kingdom (UK), in recent influenza seasons, children are offered a quadrivalent live attenuated influenza vaccine (LAIV4), and eligible adults mainly trivalent inactivated vaccine (TIV).AimTo estimate the UK end-of-season 2017/18 adjusted vaccine effectiveness (aVE) and the seroprevalence in England of antibodies against influenza viruses cultured in eggs or tissue.MethodsThis observational study employed the test-negative case-control approach to estimate aVE in primary care. The population-based seroprevalence survey used residual age-stratified samples.ResultsInfluenza viruses A(H3N2) (particularly subgroup 3C.2a2) and B (mainly B/Yamagata/16/88-lineage, similar to the quadrivalent vaccine B-virus component but mismatched to TIV) dominated. All-age aVE was 15% (95% confidence interval (CI): -6.3 to 32) against all influenza; -16.4% (95% CI: -59.3 to 14.9) against A(H3N2); 24.7% (95% CI: 1.1 to 42.7) against B and 66.3% (95% CI: 33.4 to 82.9) against A(H1N1)pdm09. For 2-17 year olds, LAIV4 aVE was 26.9% (95% CI: -32.6 to 59.7) against all influenza; -75.5% (95% CI: -289.6 to 21) against A(H3N2); 60.8% (95% CI: 8.2 to 83.3) against B and 90.3% (95% CI: 16.4 to 98.9) against A(H1N1)pdm09. For ≥ 18 year olds, TIV aVE against influenza B was 1.9% (95% CI: -63.6 to 41.2). The 2017 seroprevalence of antibody recognising tissue-grown A(H3N2) virus was significantly lower than that recognising egg-grown virus in all groups except 15-24 year olds.ConclusionsOverall aVE was low driven by no effectiveness against A(H3N2) possibly related to vaccine virus egg-adaption and a new A(H3N2) subgroup emergence. The TIV was not effective against influenza B. LAIV4 against influenza B and A(H1N1)pdm09 was effective