Household SARS-CoV-2 transmission and children: a network prospective study

Abstract Background The role of children in household transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains uncertain. Here, we describe the epidemiological and clinical characteristics of children with COVID-19 in Catalonia (Spain) and investigate the dynamics of household transmission. Methods Prospective, observational, multicenter study performed during summer and school periods (1 July-31 October, 2020), in which epidemiological and clinical features, and viral transmission dynamics were analyzed in COVID-19 patients <16 years. A pediatric index case was established when a child was the first individual infected within a household. Secondary cases were defined when another household member tested positive for SARS-CoV-2 before the child. The secondary attack rate (SAR) was calculated, and logistic regression was used to assess associations between transmission risk factors and SARS-CoV-2 infections. Results The study included 1040 COVID-19 patients <16 years. Almost half (47.2%) were asymptomatic, 10.8% had comorbidities, and 2.6% required hospitalization. No deaths were reported. Viral transmission was common among household members (62.3%). More than 70% (756/1040) of pediatric cases were secondary to an adult, whereas 7.7% (80/1040) were index cases. The SAR was significantly lower in households with COVID-19 pediatric index cases during the school period relative to summer (p=0.02), and when compared to adults (p=0.006). No individual or environmental risk factors associated with the SAR were identified. Conclusions Children are unlikely to cause household COVID-19 clusters or be major drivers of the pandemic even if attending school. Interventions aimed at children are expected to have a small impact on reducing SARS-CoV-2 transmission.

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Role of children in household transmission of COVID-19

Archives of Disease in Childhood ◽

10.1136/archdischild-2020-319910 ◽

2020 ◽

pp. archdischild-2020-319910 ◽

Cited By ~ 13

Author(s):

Jieun Kim ◽

Young June Choe ◽

Jin Lee ◽

Young Joon Park ◽

Ok Park ◽

...

Keyword(s):

Attack Rate ◽

Index Case ◽

Clinical Findings ◽

International Travel ◽

Contact Tracing ◽

Secondary Case ◽

Household Transmission ◽

Household Members ◽

Index Cases

ObjectiveTransmissibility of COVID-19 by children in the household is not clear. Herein, we describe children’s role in household transmission of COVID-19.Design and settingAll paediatric COVID-19 index cases and their household members reported from 20 January to 6 April 2020 in South Korea were reviewed. The secondary attack rate (SAR) from child index case to household secondary case was calculated. Epidemiological and clinical findings of child index case-household secondary case pair was assessed.ResultsA total of 107 paediatric COVID-19 index cases and 248 of their household members were identified. One pair of paediatric index-secondary household case was identified, giving a household SAR of 0.5% (95% CI 0.0% to 2.6%). The index case was self-quarantined at home after international travel, stayed in her room, but shared a meal table with the secondary case.ConclusionThe SAR from children to household members was low in the setting of social distancing, underscoring the importance of rigorous contact tracing and early isolation in limiting transmission within households.

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Cross-Sectional Household Transmission Study of Cryptosporidium Shows that C. Hominis Infections are A Key Risk Factor for Spread.

10.21203/rs.3.rs-659412/v1 ◽

2021 ◽

Author(s):

Caoimhe McKerr ◽

Rachel M Chalmers ◽

Kristin Elwin ◽

Heather Jones ◽

Roberto Vivancos ◽

...

Keyword(s):

Risk Factors ◽

At Risk ◽

Index Case ◽

Secondary Infection ◽

Transmission Risk ◽

Cross Sectional ◽

England And Wales ◽

Infected People ◽

North West ◽

Household Transmission

Abstract BackgroundInfection with the Cryptosporidium parasite causes over 4,000 cases of diagnosed illness (cryptosporidiosis) in England and Wales each year. The incidence of sporadic disease has not been sufficiently established, and how frequently this arises from contact with other infected people is not well documented.This project aimed to explore potential transmission in the home and attempt to identify asymptomatic infections, which might play a role in transmission. Risk factors and characteristics associated with spread of infection in the home were described including any differences between Cryptosporidium species.MethodsThe study identified cryptosporidiosis cases from North West England and Wales over a year and invited them and their household to take part. Each household was sent a study pack containing study information and a questionnaire, and stool sample kits to provide samples from consenting household members. Cryptosporidium-positive stool samples, identified by immunofluorescence microscopy, were characterised using molecular methods to help describe any patterns of transmission. Characteristics of households with and without additional cases were described, and compared using odds ratios (OR) and a multivariable logistic regression identified independent risk factors for household transmission. Data collection ran for one year, beginning in September 2018 with an initial pilot phase. ResultsWe enrolled 128 index cases and their households.Additional illness occurred in over a quarter of homes, each reporting an average of two additional cases. The majority of these were undiagnosed and unreported to surveillance. This burden was even greater in households where the index case was infected with C. hominis versus C. parvum, or the index case was under five years old, with mums and siblings most at risk of secondary infection. Only having an index case of C. hominis was independently associated with transmission in the multivariable model (OR= 4.46; p=0.01).ConclusionsCryptosporidium was a considerable burden in the home. At-risk homes were those where the index was less than five years old and/or infected with C. hominis. Of particular risk were female caregivers and siblings. Hygiene advice should be specifically directed here.This work provides evidence for humans as sources of C. hominis infection and that person-person is a key pathway. We recommend that all stools submitted for the investigation of gastrointestinal pathogens are tested for Cryptosporidium to better capture cases, inclusion of speciation data in routine surveillance, and the consideration of specific clinical advice on prevention for high-risk homes.

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Role of ACE2 And TMPRSS2 Protease In SARS-CoV-2 Dynamics Among Household Contacts of PCR-Confirmed Cases: Impact of A Combined Serological Signature Analysis On Diagnosis

10.21203/rs.3.rs-753446/v1 ◽

2021 ◽

Author(s):

Jesús Poch-Páez ◽

yeray nóvoa-medina ◽

Abián Montesdeoca-Melián ◽

Araceli Hernández-Betancor ◽

Francisco J. Rodríguez-Esparragón ◽

...

Keyword(s):

Disease Susceptibility ◽

Index Case ◽

Age Groups ◽

Testing Strategy ◽

Past Infection ◽

Household Contacts ◽

Household Transmission ◽

Household Members ◽

Benign Course

Abstract Background: To examine the hypothesis that ACE2 and TMPRSS2 expression are related to disease susceptibility and severity across age groups and to evaluate the role children play in the household transmission of SARS-CoV-2.Methods: We used a combined serological strategy to confirm past infection in subjects diagnosed with COVID-19 between march 10th and June 2nd 2020 and to evaluate their household members. We also quantified ACE2 and TPMRSS2 expression from saliva. A total of 258 households were included in the study, for a total of 650 volunteers (including 89 children aged under 18 years of age).Results: Our combined testing strategy increased our sensibility by 10%. Antibody indexes decreased with age in children and increased with age in adults. They also increased with disease severity. ACE2 expression was slightly increased in younger children. ACE2 was not related to any other factors. We did not find any relationship between TMPRSS2 expression and any of the studied factors. Children are less frequently infected by SARS-CoV-2 (OR=0,56), they present fewer symptoms and decreased severity. Age and sharing the bedroom with an index case increases the risk of acquiring the infection. The risk in adults increases with age, whereas in children, it increases in younger children. Conclusions: Our results do not support that the level of expression of ACE2 and TMPRSS2 might be related to susceptibility or severity of COVID19 disease. Children have a decreased susceptibility to SARS-CoV-2 infection compared to adults and, when infected, they present less symptoms and a more benign course.

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Characteristics of Household Transmission of COVID-19

Clinical Infectious Diseases ◽

10.1093/cid/ciaa450 ◽

2020 ◽

Vol 71 (8) ◽

pp. 1943-1946 ◽

Cited By ~ 66

Author(s):

Wei Li ◽

Bo Zhang ◽

Jianhua Lu ◽

Shihua Liu ◽

Zhiqiang Chang ◽

...

Keyword(s):

Risk Factors ◽

Attack Rate ◽

Rt Pcr ◽

Spousal Relationship ◽

Telephone Interviews ◽

Household Contacts ◽

Household Transmission ◽

Household Members ◽

Baseline Characteristics ◽

Index Cases

Abstract Background Since December 2019, SARS-CoV-2 has extended to most parts of China with >80 000 cases and to at least 100 countries with >60 000 international cases as of 15 March 2020. Here we used a household cohort study to determine the features of household transmission of COVID-19. Methods A total of 105 index patients and 392 household contacts were enrolled. Both index patients and household members were tested by SARS-CoV-2 RT-PCR. Information on all recruited individuals was extracted from medical records and confirmed or supplemented by telephone interviews. The baseline characteristics of index cases and contact patients were described. Secondary attack rates of SARS-CoV-2 to contact members were computed and the risk factors for transmission within the household were estimated. Results Secondary transmission of SARS-CoV-2 developed in 64 of 392 household contacts (16.3%). The secondary attack rate to children was 4% compared with 17.1% for adults. The secondary attack rate to the contacts within the households with index patients quarantined by themselves since onset of symptoms was 0% compared with 16.9% for contacts without quarantined index patients. The secondary attack rate to contacts who were spouses of index cases was 27.8% compared with 17.3% for other adult members in the households. Conclusions The secondary attack rate of SARS-CoV-2 in household is 16.3%. Age of household contacts and spousal relationship to the index case are risk factors for transmission of SARS-CoV-2 within a household. Quarantine of index patients at home since onset of symptoms is useful to prevent the transmission of SARS-Co-2 within a household.

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Household transmission of seasonal coronavirus infections: Results from the Flu Watch cohort study

Wellcome Open Research ◽

10.12688/wellcomeopenres.16055.1 ◽

2020 ◽

Vol 5 ◽

pp. 145 ◽

Cited By ~ 2

Author(s):

Sarah Beale ◽

Dan Lewer ◽

Robert W. Aldridge ◽

Anne M. Johnson ◽

Maria Zambon ◽

...

Keyword(s):

Cohort Study ◽

Index Case ◽

Transmission Risk ◽

Related Factors ◽

Household Transmission ◽

Clinical Onset ◽

Using Data ◽

The Uk ◽

The Impact ◽

Index Cases

Background: In the context of the current coronavirus disease 2019 (COVID-19) pandemic, understanding household transmission of seasonal coronaviruses may inform pandemic control. We aimed to investigate what proportion of seasonal coronavirus transmission occurred within households, measure the risk of transmission in households, and describe the impact of household-related factors of risk of transmission. Methods: Using data from three winter seasons of the UK Flu Watch cohort study, we measured the proportion of symptomatic infections acquired outside and within the home, the household transmission risk and the household secondary attack risk for PCR-confirmed seasonal coronaviruses. We present transmission risk stratified by demographic features of households. Results: We estimated that the proportion of cases acquired outside the home, weighted by age and region, was 90.7% (95% CI 84.6- 94.5, n=173/195) and within the home was 9.3% (5.5-15.4, 22/195). Following a symptomatic coronavirus index case, 14.9% (9.8 - 22.1, 20/134) of households experienced symptomatic transmission to at least one other household member. Onward transmission risk ranged from 11.90% (4.84-26.36, 5/42) to 19.44% (9.21-36.49, 7/36) by strain. The overall household secondary attack risk for symptomatic cases was 8.00% (5.31-11.88, 22/275), ranging across strains from 5.10 (2.11-11.84, 5/98) to 10.14 (4.82- 20.11, 7/69). Median clinical onset serial interval was 7 days (IQR= 6-9.5). Households including older adults, 3+ children, current smokers, contacts with chronic health conditions, and those in relatively deprived areas had the highest transmission risks. Child index cases and male index cases demonstrated the highest transmission risks. Conclusion: Most seasonal coronaviruses appear to be acquired outside the household, with relatively modest risk of onward transmission within households. Transmission risk following an index case appears to vary by demographic household features, with potential overlap between those demonstrating the highest point estimates for seasonal coronavirus transmission risk and COVID-19 susceptibility and poor illness outcomes.

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Transmission of Onychomycosis and Dermatophytosis between Household Members: A Scoping Review

Journal of Fungi ◽

10.3390/jof8010060 ◽

2022 ◽

Vol 8 (1) ◽

pp. 60

Author(s):

Aria Jazdarehee ◽

Leilynaz Malekafzali ◽

Jason Lee ◽

Richard Lewis ◽

Ilya Mukovozov

Keyword(s):

Risk Factors ◽

Previous History ◽

Household Transmission ◽

Scoping Literature Review ◽

History Of ◽

Sources Of Infection ◽

Household Cleaning ◽

Household Members ◽

Underlying Mechanisms

Onychomycosis is a common fungal infection of the nail, caused by dermatophytes, non-dermatophytes, and yeasts. Predisposing factors include older age, trauma, diabetes, immunosuppression, and previous history of nail psoriasis or tinea pedis. Though many biological risk factors have been well characterized, the role of the environment has been less clear. Studies have found evidence of transmission in 44% to 47% of households with at least one affected individual, but the underlying mechanisms and risk factors for transmission of onychomycosis between household members are incompletely understood. A scoping literature review was performed to characterize and summarize environmental risk factors involved in the transmission of onychomycosis within households. A total of 90 papers met the inclusion criteria, and extracted data was analyzed in an iterative manner. Shared household surfaces may harbor dermatophytes and provide sources for infection. Shared household equipment, including footwear, bedding, and nail tools, may transmit dermatophytes. The persistence of dermatophytes on household cleaning supplies, linen, and pets may serve as lasting sources of infection. Based on these findings, we provide recommendations that aim to interrupt household transmission of onychomycosis. Further investigation of the specific mechanisms behind household spread is needed to break the cycle of transmission, reducing the physical and social impacts of onychomycosis.

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Risk of Secondary Household Transmission of COVID-19 from Health Care Workers in a Hospital in Spain

Epidemiologia ◽

10.3390/epidemiologia3010001 ◽

2021 ◽

Vol 3 (1) ◽

pp. 1-10

Author(s):

Miren Remón-Berrade ◽

Sara Guillen-Aguinaga ◽

Isabel Sarrate-Adot ◽

Maria Pilar Garcia-Garcia ◽

Maria del Carmen Lerga-Berruezo ◽

...

Keyword(s):

Risk Factors ◽

Health Care ◽

Health Care Workers ◽

Attack Rate ◽

Index Case ◽

Acute Infection ◽

Transmission Risk ◽

Household Contacts ◽

Care Workers ◽

Index Cases

Background: Hospital health care workers are at high risk of developing COVID-19 and transmitting the disease to their family upon returning home; the aim here is to estimate the secondary attack rate of COVID-19 in household contacts of health care workers and their transmission risk factors. Material and Methods: COVID-19 cases in the health care workers of an academic hospital in Pamplona, Spain, from 2 March to 26 May 2020, were followed up. The secondary attack rate (SAR) was estimated from cases in household contacts of index cases and their risk factors by Poisson regression. Results: 89 index cases were studied from 99 notified cases in health care workers (89.0%), excluding secondary cases or those who lived alone. Forty-six secondary cases confirmed by the laboratory were found among 326 household contacts, a secondary attack rate of 14.11% (95% CI 10.75–18.31), and 33 household contacts with acute infection symptoms without microbiologic confirmation 10.12% (95% CI 7.30–13.87). Considering all the cases, the secondary attack rate was 27.3 (95% CI 22.75–32.38). Risk factors were the gender and profession of the index case, the number of people living in the household, and the number of persons per bedroom. When the index case health worker used a single room, it had a protective effect, with an incidence rate ratio (IRR) of 0.493 (95% CI 0.246–0.985); Conclusions: The secondary attack rate found among household contacts of health care workers is high. The preventive isolation of health care workers in individual rooms in their house may reduce the transmission in their families.

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A meta-analysis on the role of children in SARS-CoV-2 in household transmission clusters

Clinical Infectious Diseases ◽

10.1093/cid/ciaa1825 ◽

2020 ◽

Cited By ~ 2

Author(s):

Yanshan Zhu ◽

Conor J Bloxham ◽

Katina D Hulme ◽

Jane E Sinclair ◽

Zhen Wei Marcus Tong ◽

...

Keyword(s):

Confidence Interval ◽

Risk Ratio ◽

Attack Rate ◽

Index Case ◽

Meta Analysis ◽

Household Contacts ◽

Household Transmission ◽

Potential Vaccine ◽

Index Cases

Abstract The role of children in the spread of SARS-CoV-2 remains highly controversial. To address this issue, we performed a meta-analysis of the published literature on household SARS-CoV-2 transmission clusters (n=213 from 12 countries). Only 8 (3.8%) transmission clusters were identified as having a paediatric index case. Asymptomatic index cases were associated with a lower secondary attack in contacts than symptomatic index cases (estimate risk ratio [RR], 0.17; 95% confidence interval [CI], 0.09-0.29). To determine the susceptibility of children to household infections the secondary attack rate (SAR) in paediatric household contacts was assessed. The secondary attack rate in paediatric household contacts was lower than in adult household contacts (RR, 0.62; 95% CI, 0.42-0.91). These data have important implications for the ongoing management of the COVID-19 pandemic, including potential vaccine prioritization strategies.

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401. Natural History of Shedding and Household Transmission of Severe Acute Respiratory Syndrome Coronavirus 2 Using Intensive High-Resolution Sampling

Open Forum Infectious Diseases ◽

10.1093/ofid/ofab466.602 ◽

2021 ◽

Vol 8 (Supplement_1) ◽

pp. S302-S302

Author(s):

Jonathan Altamirano ◽

Prasanthi Govindarajan ◽

Andra Blomkalns ◽

Sean Leary ◽

India Robinson ◽

...

Keyword(s):

Risk Factors ◽

Index Case ◽

Socioeconomic Indicators ◽

Rt Pcr ◽

Viral Spread ◽

Household Contacts ◽

Household Transmission ◽

Secondary Infections ◽

History Of ◽

Index Cases

Abstract Background In order to mitigate the spread of SARS-CoV-2 and the COVID-19 pandemic, public health officials have recommended self-isolation, self-quarantine of exposed household contacts (HHC), and mask use to limit viral spread within households and communities. While household transmission of SARS-CoV-2 is common, risk factors for HHC transmission are poorly understood. Methods In this prospective cohort study, we enrolled 37 households with at least one reverse transcription polymerase chain reaction-confirmed (RT-PCR) COVID-19 index case from March 2020 - March 2021, in order to calculate secondary attack rates (SAR) and define risk factors for secondary infections. Participants were tested daily for SARS-CoV-2 via RT-PCR, using self-collected lower nasal samples. Households were followed until all members tested negative for seven consecutive days. We collected demographics, medical conditions, relationship to index case, and socioeconomic indicators. Subgroup data analysis was conducted and stratified by positivity status. Results Of 99 enrolled participants, 37 were index cases and 62 were household contacts (HHC), of whom 25 HHC were infected (40.3%). Secondary attack rate (SAR) was highest among adults caring for a parent (n=4/4, 100%) and parents of index cases (5/10, 50%). Households whose income came from service work had greater risk of transmission compared to households whose primary income was technology (n=5/7; 71.4% vs 3/8; 37.5% respectively). Pediatric contacts were at lower risk of infection when compared to adult contacts (n=5/18, 27.8% vs n=20/44, 45.5% respectively). Conclusion This study suggests that household transmission represents a key source of community-based infection of SARS-CoV-2. Allocating resources for education/training regarding prevention among infected individuals and their close contacts will be critical for control of future outbreaks of SARS-CoV-2. Disclosures All Authors: No reported disclosures

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A meta-analysis on the role of children in SARS-CoV-2 in household transmission clusters

10.1101/2020.03.26.20044826 ◽

2020 ◽

Cited By ~ 25

Author(s):

Yanshan Zhu ◽

Conor J. Bloxham ◽

Katina D. Hulme ◽

Jane E. Sinclair ◽

Zhen Wei Marcus Tong ◽

...

Keyword(s):

Confidence Interval ◽

Family Member ◽

Attack Rate ◽

Index Case ◽

Meta Analysis ◽

Household Contacts ◽

Household Transmission ◽

Potential Vaccine ◽

Index Cases

ABSTRACTThe role of children in the spread of SARS-CoV-2 remains highly controversial. To address this issue, we performed a meta-analysis of the published literature on household SARS-CoV-2 transmission clusters (n=213 from 12 countries). Only 8 (3.8%) transmission clusters were identified as having a paediatric index case. Asymptomatic index cases were associated with a lower secondary attack in contacts than symptomatic index cases (estimate risk ratio [RR], 0.17; 95% confidence interval [CI], 0.09-0.29). To determine the susceptibility of children to household infections the secondary attack rate (SAR) in paediatric household contacts was assessed. The secondary attack rate in paediatric household contacts was lower than in adult household contacts (RR, 0.62; 95% CI, 0.42-0.91). These data have important implications for the ongoing management of the COVID-19 pandemic, including potential vaccine prioritization strategies.40-word summaryIn household transmission clusters of SARS-CoV-2 children are unlikely to be the index case. Children are also less likely than adults to be infected with SARS-CoV-2 from a family member.

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