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Over the last six months, I’ve learned a lot about how SARS-CoV-2 spreads. Based on, let’s confirm that evidence has shown so far about the dynamics of SARS-CoV-2 infection, high-risk activities, and the environment. Recent articles My colleague and i Clinical infection.
The risk of infection is complex and multidimensional. It includes many contact patterns (ie, duration, proximity, activity), individual factors, environmental factors (ie, outdoor, indoor), and socio-economic factors (ie, crowded housing, work instability). Depends on the factors of.
As I outlined Recent Twitter threadLet’s take a look at each of these.
Contact pattern. We now know that persistent close contact drives most of the infections and clusters. For example, contact and gathering with close family and friends is at higher risk of infection than shopping in the market or meeting a simple community.
Frequent daily contact with probands, such as spouses and partners who eat nearby or share the same sleeping space, even within the same household, is associated with an increased risk of infection. ..
For non-home contacts, engaging in group activities such as eating together or playing board games, as well as usually large cluster gatherings such as weddings and birthday parties. , It is known that the risk of infection is high. Other examples include pub gatherings, church services, and close business talks. These findings suggest that group activities are at increased risk of infection. Risk increases with longer and more frequent exposures, proximity, number of contacts, and group activities, especially diet.
Individual factors. The individual factors of infectivity vary greatly.Many people Don’t infect anyone Or it infects one person. Many secondary cases are caused by a small number of infected people. Many factors are involved, but individual infectious differences play a major role.
Looking at viral load dynamics and contact tracing studies, infected individuals are highly infectious, perhaps for a short period of 1-2 days and 5 days after the onset of symptoms. So far, no infections have been recorded since the first week of onset of symptoms.
Asymptomatic patients can infect others with the virus, but new evidence detailed in two publications— Preprint And published paper — Suggests that asymptomatic probands infect fewer secondary probands. Incidence (the number of people at risk from exposure who get sick) is highly correlated with the severity of symptoms.
Infection is also affected by other host factors, such as the host’s defenses and age.For example, susceptibility to infection given the same exposure Increase with age.. It is higher in people over the age of 60 than in young or middle-aged adults.
Environmental factors. The impact of contact patterns also depends on the encounter settings. Contact tracing research Indoor setting It is associated with a 20 times higher risk of infection than in the outdoor environment.
Prolonged indoor contact in a crowded and poorly ventilated environment significantly increases the risk of infection. However, you can reduce the risk by reducing occupancy and opening windows and doors to improve ventilation.
The largest outbreaks from around the world have been reported in long-term care facilities (such as nursing homes), homeless shelters, prisons, and meat stuffing plants where many people work, live together, and share communal spaces for several hours.
All of the largest clusters of cases observed in the United States are related to prisons or prisons.In Germany’s largest meat packaging factoryThe common point of potential contact was the workplace, but the risk of a single shared apartment or bedroom, or carpooler was higher.
Socio-economic factors. Global figures suggest that the COVID-19 pandemic is strongly shaped by structural inequality, unfavorable living and working conditions, and structural racism that drives family and occupational risks. I am.
People in low-wage professions often have to work outside their homes and are classified as essential workers who may travel to work on public transport. These occupations often carry more social contact and exposure risk due to long working hours and work instability.
Households in socio-economically disadvantaged areas are prone to overcrowding, increasing the risk of infection within the household. These disparities also form the strong geographic heterogeneity found in the burden of incident and death.
UK Public Health Service Surveillance report While the number of infectious diseases in the UK is increasing primarily in the 20-29 and 30-39 age groups, SARS-CoV-2 isolates people as they are employed in low-paying jobs. ..
To Madrid, It has the highest incidence in 37 regions, four times the average in other parts of Spain. There are common factors in these areas: they are poorer, more densely populated, and have a large immigrant population.
Previous research Although there is a social distance between 2009 H1N1 The pandemic has succeeded in reducing infectious diseases, and the effect was most pronounced in households with high socio-economic advantages. Similar discoveries have been made for COVID-19.
COVID-19 is now Endemic Some parts of England combined with serious deprivation. Poor housing; a large black, Asian, and ethnic minority community. The national blockade had little effect on reducing the level of infection in these areas of northern England.
Real duplication of Causes of mortality and deprivation You can see it in the figure below. Scottish data show that the age-standardized mortality associated with COVID-19 in the least disadvantaged quintile is more than twice (2.3 times higher) than in the least deprived quintile. I will.
In summary, the imbalanced impact of COVID-19 on poor households and the racial and ethnic disparities found in many countries urgently update COVID-19’s definition of “vulnerable” population. , Emphasizes the need to address these inequality.
These include social and income protection and support to ensure that low-wage, unpaid, contract workers can afford to follow quarantine and quarantine recommendations, which usually do not guarantee minimum working hours. .. Providing protective equipment to the workplace and community environment is also essential.
Peak viral load that occurs early in the course of the disease indicates that immediate self-isolation with the onset of symptoms is required to prevent continued infection (minimum 5 days). Patient education should prioritize quarantine practices and policies should include supported quarantine.
There are many things you can do in your family to reduce infection. Clear instructions and support should be provided so that people with positive symptoms or test results can be isolated from their contacts.
Policy makers and health professionals can help the general public distinguish between low-risk and high-risk activities, and the message of the environment and public health goes to alternatives for safer interactions. Various risks can be communicated to the public to support their involvement.
Without clear public health communication about risk, individuals stick to unlikely sources of infection (outdoor activities) while underestimating high-risk settings such as family and friend gatherings and indoor settings. There is a possibility. Therefore, the advice should be clear and consistent with the dynamics of communication. Avoid crowded, indoor, poorly ventilated environments. Spend more time outdoors. Keep the distance (more is better, but 6 feet is not a panacea). Improve ventilation: Open windows and doors. Wear a mask indoors. Please wash your hands.
High-risk environments such as nursing homes, prisons, shelters, and meat filling factories require public health strategies tailored to these specific environments. This should include personal protective equipment and routine inspections to identify individuals infected early in the course of the disease.
Modeling studies, computer simulations, and aerodynamics of droplets may contribute to understanding the infection, while contact tracing studies include actual infectious dynamics and personal and personal and related to SARS-CoV-2 infection. Provides structural factors. Make health plans, mitigate prevalent events, and control your current pandemic.
Muge Cevik, MD, MScIs a clinician and researcher in Infectious Diseases and Medical Virology at the University of St Andrews.Her research subject is HIV, tuberculosis, Viral hepatitis, Emerging infectious diseases, and tropical infections in low- and middle-income countries. During the COVID-19 pandemic, in addition to working at the forefront of response, she provided scientific information to the Chief Medical Officer of Scotland and was an expert on the WHO Epidemic Information Network on COVID-19-related infodemics. Provided information. ..