COVID-19 may spread more easily in crowded homes. Studies looking at the incidence of common infectious diseases such as colds, asthma, and influenza have found an association between prevalence and crowding.
Crowding is considered to be stressful to health and well-being across different cultures and aspects of life in low-, middle- and high-income countries.
Household Crowding
Household crowding is a condition where the number of occupants exceeds the capacity of the dwelling space available, whether measured as rooms, bedrooms, or floor area, resulting in adverse physical and mental health outcomes. Crowding is a result of a mismatch between the dwelling and the household. The level of crowding relates to the size and design of the dwelling, including the size of the rooms, and to the type, size, and needs of the household, including any long-term visitors.
Whether a household is “crowded” depends not only on the number of people sharing the dwelling but on their age, their relationship, and their sex.
Adverse effects may occur through a number of mechanisms. The factors include: sharing a bed or bedroom, increased physical contact, lack of sleep, lack of privacy, an inability to care adequately for sick household members, and poor hygiene practices.
People may crowd into particular rooms in their homes to avoid cold or uninhabitable parts of the dwelling or to save on heating and other costs.
The effects of crowding can be broadly defined as the hazards associated with inadequate space within the dwelling for living, sleeping, and household activities.
Worldwide, crowding is often a marker of poverty and social deprivation. It has been identified by the United Nations as one of five deprivations that suggest an informal settlement should be characterized as a slum.
Housing has a powerful influence on the transmission of infections that spread via physical contact and airborne droplets, such as tuberculosis.
Health Effects
Several studies have reported a direct association between crowding and adverse health outcomes, such as infectious disease and mental health problems. In addition, researchers have connected crowding to poor educational attainment.
Overcrowding poses serious direct and indirect health risks to all segments of the population, particularly the elderly, young children, and the disabled. Overcrowding results in insufficient ventilation in homes, causing or exacerbating respiratory illness, susceptibility to disease, the severity of diseases, the spreading of illness, and mortality due to disease all. Overcrowding increases accidents in the home and community.
In camps, overcrowding exacerbates health risks related to insufficient and poor water supply and poor sanitation systems in the camps.
Overcrowding physically and emotionally overburdens mothers and other caregivers, increasing the health risks of dependents. Lack of space and overcrowding directly impacts the physical development and psychological well-being of disabled residents.
High population density provides greater opportunity for contact between infectious diseases and susceptible people which leads to higher transmission rates. The large concentration of population once an epidemic starts leads to higher transmission rates.
According to the WHO, from a purely epidemiological perspective, the provision of sufficient residential space and avoiding overcrowding are high-impact public health interventions to reduce the rate of transmission of communicable diseases.
The transmission of the infection can be avoided by staying away from affected people i.e. by practicing social distancing.
Pneumonia
The risk of pneumonia is increased among people living in crowded conditions, such as students in dormitories, people living in institutions, military personnel in barracks, and people living in nursing homes.
Pneumonia is a leading cause of hospitalization in both children and adults. Pneumonia accounts for 15% of all deaths of children under 5 years old, killing 808 694 children in 2017. The people most at risk are infants and young children, adults 65 or older, and people who have other health problems.
To reduce the chance that you will get pneumonia, try to stay away from crowded places.
Social Effects
Overcrowding contributes to far-reaching social problems; it places a strain on social relations within the home and community. Overcrowding in schools and homes is linked to substandard education and functional illiteracy and may be related to increased child labor. It is a ‘push factor’ in the decisions leading to girls’ early marriage (before the age of 18) which, in turn, leads to serious health and social ramifications for women and children. Overcrowding affects women’s access to social and economic resources; it increases their responsibilities in the home and burdens their time.
When people experience crowding, their social interactions change. Two results are common: they withdraw from others, creating more psychological space when physical space is limited, and they become more irritable and potentially aggressive.
Psychological Effects
Direct and indirect psychological effects result from overcrowding. Lack of privacy is linked to depression and other negative psychological outcomes. Overcrowding contributes to psychological frustrations which, in turn, have a bearing on behavioral responses and residents’ ability to cope with the conditions.
Crowding is stressful for children as well as adults, and particularly for women, leading to poor social relationships, poor childcare, aggression, or withdrawal. Doubling up of households, particularly unrelated households appear to contribute to psychological stress.
Prison Overcrowding
The rise of overcrowding in prisons has resulted in many issues such as poor health care, increased gang activity within the prisons, an increase in individual mental health issues, violence, the spread of disease, and staff stress.
For communities, inadequate shelter and overcrowding are major factors in the transmission of diseases with epidemic potential such as acute respiratory infections, meningitis, typhus, cholera, scabies, etc. Outbreaks of disease are more frequent and more severe when the population density is high.
Prison overcrowding also has other effects on the health and wellbeing of the people living in these conditions and may also adversely affect public health and the prison system. It can increase the prevalence of diseases, particularly infectious and psychiatric disorders.
It may also hinder the work of social rehabilitation and lead to inhuman, cruel, or degrading treatment.
Crowd Disasters
Crowd forces can reach levels that almost impossible to resist or control. Virtually all crowd deaths are due to compressive asphyxia. Evidence of bent steel railings after several fatal crowd incidents show that forces of more than 4500N (1,000lbs) occurred. Forces are due to pushing, and the domino effect of people leaning against each other.
Compressive asphyxia has occurred from people being stacked up vertically, one on top of the other, or horizontal pushing and leaning forces.
Horizontal forces are sufficient to cause compressive asphyxia would be more dynamic as people push off against each other to obtain breathing space.
Insufficient consideration of human space requirements has resulted in the inadequate design of many areas where pedestrians may be required to accumulate in large groups. In some instances, overcrowding of these areas has resulted in injury and loss of life.
Ventilation
Bacteria and viruses can travel through the air, causing and worsening diseases. They get into the air easily. When someone sneezes or coughs, tiny water or mucous droplets filled with viruses or bacteria scatter in the air or end up in the hands where they spread on surfaces like doorknobs. Inhaling these viruses or bacteria can spread coughs, colds, influenza, tuberculosis, and other infectious agents.
Crowded conditions with poor air circulation can promote this spread. Some bacteria and viruses thrive and circulate through poorly maintained building ventilation systems. Damp, humid air can increase the survival rate of viruses indoors.
In addition, some individuals with allergies react to endotoxins, substances that come from the broken-down cells of dead bacteria. These microscopic particles have been associated with coughing, wheezing, and worsening asthma.
Bacteria in the soil produce endotoxins, so they are virtually everywhere outdoors. They can come indoors with pets, pests, humidifiers, kitchen compost bins, and outdoor air. Walking, dry mopping, and other activities can cause them to become airborne once inside.
Effective ventilation may also help keep bacteria, viruses, and other pollutants out of the indoor air. Ventilation can also limit moisture. Damp indoor spaces foster the growth and transmission of viruses and bacteria. Controlling moisture indoors can limit the spread of these infectious diseases and also limit mold, dust mite, and cockroach growth.
Avoid overcrowding, particularly in public transport and public buildings. The scientists say simple steps, such as opening both doors and windows, can dramatically increase airflow rates in buildings. Room ventilation, open space, sanitization of protective apparel, and proper use and disinfection of toilet areas can effectively limit the concentration of SARS-CoV-2 RNA in aerosols.
