Household transmission of SARS-CoV-2 in Norway; a prospective, longitudinal study showing increased transmissibility of the Alpha variant (B.1.1.7) compared with other variants

ABSTRACT Background We studied the secondary attack rate (SAR), risk factors, and precautionary practices of household transmission in a prospective longitudinal study. Moreover, we compared household transmission between the Alpha (B.1.1.7) variant and non-variants of concern (non-VOCs). Methods We recruited households of confirmed COVID-19 cases from May 2020 to May 2021. Households received 8 home visits over 6 weeks. Biological samples and questionnaire data were collected. Results We recruited 70 confirmed COVID-19 cases and 146 household contacts. Transmission occurred in 60% of the households; the overall SAR for household contacts was 49.6%. The SAR was significantly higher for the Alpha variant (77.8%) compared with non-VOC variants (42.5%) and was associated with a higher viral load. SAR was higher in household contacts aged ≥40 years (64%) than in younger contacts (40-47%), and for contacts of cases with loss of taste/smell. Close contact prior to confirmation of infection tended to give a higher SAR. A significantly lower SAR was found for sleeping separately from the primary case after confirmation of infection. Conclusion We found substantial household transmission, particularly for the Alpha variant. Precautionary practices seem to reduce SAR; however, prevention of transmission within households may become difficult with more transmissible variants.

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Household Transmission of SARS-CoV-2: A Prospective Longitudinal Study Showing Higher Viral Load and Increased Transmissibility of the Alpha Variant Compared to Previous Strains

Microorganisms ◽

10.3390/microorganisms9112371 ◽

2021 ◽

Vol 9 (11) ◽

pp. 2371

Author(s):

Cathinka Halle Julin ◽

Anna Hayman Robertson ◽

Olav Hungnes ◽

Gro Tunheim ◽

Terese Bekkevold ◽

...

Keyword(s):

Viral Load ◽

Longitudinal Study ◽

Digital Pcr ◽

Primary Case ◽

Prospective Longitudinal Study ◽

Viral Loads ◽

Household Contacts ◽

Household Transmission ◽

Alpha Variant ◽

Prospective Longitudinal

We studied the secondary attack rate (SAR), risk factors, and precautionary practices of household transmission in a prospective, longitudinal study. We further compared transmission between the Alpha (B.1.1.7) variant and non-Variant of Concern (non-VOC) viruses. From May 2020 throughout April 2021, we recruited 70 confirmed COVID-19 cases with 146 household contacts. Participants donated biological samples eight times over 6 weeks and answered questionnaires. SARS-CoV-2 infection was detected by real-time RT-PCR. Whole genome sequencing and droplet digital PCR were used to establish virus variant and viral load. SARS-CoV-2 transmission occurred in 60% of the households, and the overall SAR for household contacts was 50%. The SAR was significantly higher for the Alpha variant (78%) compared with non-VOC viruses (43%) and was associated with a higher viral load. SAR was higher in household contacts aged ≥40 years (69%) than in younger contacts (40–47%), and for contacts of primary cases with loss of taste/smell. Children had lower viral loads and were more often asymptomatic than adults. Sleeping separately from the primary case reduced the risk of transmission. In conclusion, we found substantial household transmission, particularly for the Alpha variant. Precautionary practices seem to reduce SAR, but preventing household transmission may become difficult with more contagious variants, depending on vaccine use and effectiveness.

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A prospective longitudinal study of tuberculosis among household contacts of smear-positive tuberculosis cases in Lima, Peru

BMC Infectious Diseases ◽

10.1186/s12879-016-1616-x ◽

2016 ◽

Vol 16 (1) ◽

Cited By ~ 7

Author(s):

Larissa Otero ◽

Lena Shah ◽

Kristien Verdonck ◽

Tullia Battaglioli ◽

Timothy Brewer ◽

...

Keyword(s):

Longitudinal Study ◽

Prospective Longitudinal Study ◽

Household Contacts ◽

Prospective Longitudinal

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High resting heart rate protects against childhood risk factors in predicting adult psychopathy

Journal of Criminal Psychology ◽

10.1108/jcp-01-2021-0003 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

David P. Farrington ◽

Henriette Bergstrøm

Keyword(s):

Risk Factors ◽

Heart Rate ◽

Longitudinal Study ◽

Protective Factor ◽

Psychosocial Risk Factors ◽

Psychosocial Risk ◽

Resting Heart Rate ◽

Prospective Longitudinal Study ◽

Content Type ◽

Prospective Longitudinal

Purpose Previous research has indicated that low resting heart rate (RHR), measured at age 18, predicts later psychopathy, and that high RHR acts as a protective factor in nullifying the influence of several psychosocial risk factors in predicting later antisocial and criminal outcomes. This paper aims to investigate high RHR as a protective factor against age 8–10 psychosocial risk factors in predicting psychopathy factors at age 48 (measured by the PCL:SV). Design/methodology/approach Data collected in the Cambridge Study in Delinquent Development are analyzed. This is a prospective longitudinal study of 411 London males from age 8 to age 61. Findings This paper first reports the age 8–10 psychosocial risk factors that predict the interpersonal/affective Factor 1 and the lifestyle/antisocial Factor 2. Then interaction effects with high RHR are studied. The results indicate that high RHR acts as a protective factor against a convicted father and a depressed mother in predicting both psychopathy factors. It also protected against harsh discipline, large family size, low verbal IQ, high hyperactivity, poor parental supervision and a high delinquency-rate school in predicting one of these psychopathy factors, and against a convicted mother in a sensitivity analysis. Originality/value This is the first ever longitudinal study showing that high RHR acts as a protective factor in the prediction of psychopathy. The replicated results with different antisocial outcomes show that more research is warranted on the protective effects of high RHR.

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Incidence of crown fracture and risk factors in the primary dentition: a prospective longitudinal study

Dental Traumatology ◽

10.1111/edt.12288 ◽

2016 ◽

Vol 32 (6) ◽

pp. 450-456 ◽

Cited By ~ 4

Author(s):

Patrícia Corrêa-Faria ◽

Saul Martins Paiva ◽

Maria Letícia Ramos-Jorge ◽

Isabela Almeida Pordeus

Keyword(s):

Risk Factors ◽

Longitudinal Study ◽

Primary Dentition ◽

Prospective Longitudinal Study ◽

Prospective Longitudinal

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A prospective, longitudinal study of risk factors for early onset of delinquency among maltreated youth

Children and Youth Services Review ◽

10.1016/j.childyouth.2019.05.023 ◽

2019 ◽

Vol 102 ◽

pp. 222-230 ◽

Cited By ~ 8

Author(s):

Minhae Cho ◽

Wendy Haight ◽

Won Seok Choi ◽

Saahoon Hong ◽

Kristine Piescher

Keyword(s):

Risk Factors ◽

Longitudinal Study ◽

Early Onset ◽

Prospective Longitudinal Study ◽

Prospective Longitudinal

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Risk factors for stress and urge urinary incontinence during pregnancy and the first year postpartum: a prospective longitudinal study

International Urogynecology Journal ◽

10.1007/s00192-021-04788-w ◽

2021 ◽

Author(s):

Shiow-Ru Chang ◽

Wei-An Lin ◽

Ting-Chen Chang ◽

Ho-Hsiung Lin ◽

Chien-Nan Lee ◽

...

Keyword(s):

Risk Factors ◽

Urinary Incontinence ◽

Longitudinal Study ◽

Urge Urinary Incontinence ◽

First Year ◽

Prospective Longitudinal Study ◽

Prospective Longitudinal

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A Prospective Longitudinal Study Evaluating The Influence of Immunosuppressives and Other Factors On COVID-19 in Autoimmune Rheumatic Diseases

10.21203/rs.3.rs-805748/v1 ◽

2021 ◽

Author(s):

Abhishek Patil ◽

Chanakya K ◽

Padmanabha Shenoy ◽

Chandrashekara S ◽

Vikram Haridas ◽

...

Keyword(s):

Risk Factors ◽

Longitudinal Study ◽

General Population ◽

Lung Disease ◽

Rheumatic Diseases ◽

Case Fatality ◽

Geographic Region ◽

Prospective Longitudinal Study ◽

Autoimmune Rheumatic Diseases ◽

Prospective Longitudinal

Abstract Background We conducted this study to identify the influence of prolonged use of hydroxychloroquine(HCQ), glucocorticoids (GC) and other immunosuppressants (IS) on occurrence and outcome of COVID-19 in patients with autoimmune rheumatic diseases (AIRDs). Methods This was a prospective, multicenter, non-interventional longitudinal study across 15 specialist rheumatology centers. Consecutive AIRD patients on treatment with immunosuppressants were recruited and followed up longitudinally to assess parameters contributing to development of COVID-19 and its outcome. Results COVID-19 occurred in 314(3.45%) of 9212 AIRD patients during a median follow up of 177 (IQR 129,219) days. Long term HCQ use had no major impact on the occurrence or the outcome of COVID-19. Glucocorticoids in moderate dose (7.5-20mg/day) conferred higher risk (RR = 1.72) of infection. Among the IS, Mycophenolate mofetil (MMF), Cyclophosphamide (CYC) and Rituximab (RTX) use was higher in patients with COVID 19. However, the conventional risk factors such as male sex (RR = 1.51), coexistent diabetes mellitus (RR = 1.64), pre-existing lung disease (RR = 2.01) and smoking (RR = 3.32) were the major contributing risk factors for COVID-19. Thirteen patients (4.14%) died, the strongest risk factor being pre-existing lung disease (RR = 6.36, p = 0.01). Incidence ((17.5 vs 5.3 per 1 lakh (Karnataka) and 25.3 vs 7.9 per 1 lakh(Kerala) ) and case fatality (4.1% vs 1.3 % (Karnataka) and 4.3% vs 0.4% (Kerala)) rate of COVID-19 was significantly higher (p < 0.001) compared to the general population of the corresponding geographic region. Conclusions Immunosuppressants have a differential impact on the risk of COVID-19 occurrence in AIRD patients. Older age, males, smokers, hypertensive, diabetic and underlying lung disease contributed to higher risk. The incidence rate and the case fatality rate in AIRD patients is much higher than that in the general population.

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