PSyndemics refers to the evaluation of how social and health conditions arise, in what ways they interact, and what drivers may produce their interactions.
No disease exists in isolation and that often population health can be understood through a confluence of factors-climate change or social inequality producing multiple health conditions that afflict some groups and not others.
Syndemics are not like pandemics producing clustered conditions equally around the world.
Instead, syndemics reflect population-level trends within certain states, regions, cities, or towns.
A syndemic is understood to be the aggregation of two or more concurrent or sequential epidemics or disease clusters in a population with biological interactions, which exacerbate the prognosis and burden of disease.
Syndemics develop under health disparities: poverty, stress, climate, or structural violence.
A syndemic approach departs from the biomedical approach to diseases to diagnostically isolate, and treat diseases as distinct entities separate from other diseases and independent of social contexts.
A syndemic refers to a synergistic epidemic with disease concentration, disease interaction, and their underlying social forces are the core concepts.
Disease co-occurrence, is known as comorbidity and coinfection.
The difference between “comorbid” and “syndemic” is per Mustanski et al.
It is possible for two afflictions to be comorbid, but not syndemic; Two or more diseases can be comorbid without interactions, or interaction occurs but it is beneficial, not deleterious.
Syndemic theory provides a framework for the analysis of adverse disease interactions, including their causes and consequences for human life and well-being.
Although the majority of this research has focused on HIV.
Syndemic methods seek to understand why and how social and health conditions cluster together, interact, and are driven by shared forces, from climate, as escalation of heat, rain, drought, and events to poverty, such as food insecurity, poor housing, lack of safety, and limited work opportunities.
Epidemiology provides opportunities to investigate the synergistic ways in which diseases emerge and interact with social and health conditions.
Diseases regularly interact and this interaction influences disease course, expression, severity, transmission, and diffusion.
The interaction among diseases may be both indirect and direct.
One disease can assist the physical transmission of the microbe causing another disease: genital-tract ulceration caused by syphilis allowing sexual transmission of HIV.
One disease may enhance the virulence of another: herpes simplex virus co-infection exacerbates HIV infection with progression to AIDS, periodontal bacteria may enhance the virulence of herpesvirus, HIV-infected individuals are more susceptible to tuberculosis; changes in biochemistry or damage to organ systems, diabetes weakening the immune system, promotes the progression of another disease.
Lethal synergism between influenza virus and pneumococcus, causes excess mortality from secondary bacterial pneumonia during influenza epidemics.
Influenza virus alters the lungs in ways that increase the adherence, invasion and induction of disease by pneumococcus, alters the immune response with weakened ability to clear pneumococcus or, alternately amplifying the inflammatory cascade.
Syndemics: possible asthma and infectious disease syndemic, a malnutrition and depression syndemic, a TB, HIV and violence syndemic, the whooping cough, influenza, tuberculosis syndemic, the HIV incidence, substance use, mental health, childhood sexual abuse, and intimate partner violence syndemics, the HIV and STD syndemic, the stress and obesity syndemic, the HIV infection, mental health and substance abuse syndemic, the physical inactivity and obesity/diabetes syndemic, HIV infection and opportunistic microbial infections and viral-caused malignancies like Kaposi’s sarcoma, periodontitis and herpes virus: bacteria of several different species that adhere to and reproduce on tooth surfaces under the gum line multiply when bodily defenses are weakened by an HSV infection of the periodontium, HIV being transiently suppressed during an acute measles infection.
Measles virus infection causes lymphopenia, a reduction in the number of CD4+ T lymphocytes circulating in the blood, and low point occurs just prior to the onset of the characteristic skin rash.
Within a month of this nadir, the number of lymphocytes returns to normal levels.
The drop in HIV virus levels may be due to a lack of target CD4+ T cells in which they replicate, or measles virus may stimulate the production of proteins suppressing HIV replication, including the β-chemokines, CD8+ cell noncytotoxic anti-HIV response, and the cytokines IL-10 and IL-16.m
Median plasma levels of a chemokine that attracts immune system components like eosinophils, monocytes, and lymphocytes is higher in HIV-infected children with measles than in those without measles.
As a result of the floral changes produced by global warming, an escalation is occurring in global rates of allergies and asthma.
Allergic diseases constitute the sixth leading cause of chronic illness in the United States, impacting 17 percent of the population.
Asthma affects about 8 percent of the U.S. population, with rising tendency, especially in low income, ethnic minority neighborhoods in cities: In 1980 asthma affected only about three percent of the U.S. population according to the U.S. CDC.
Asthma among children has been increasing at an even faster pace than among adults.
The asthma prevalence among American Indians, Alaska Natives and black people is 25 percent higher than in white people.
Increases in asthma rates have occurred despite improvements in air quality produced by the passage and enforcement of clean air legislation.
Air-borne pollens have been found to attach themselves to diesel particles from truck or other vehicular exhaust floating in the air, resulting in heightened rates of asthma in areas where busy roads bisect densely populated areas, most notably in poorer inner-city areas.
For every elevation of 10 μg/m3 in particulate matter concentration in the air a six percent increase in cardiopulmonary deaths occurs.
Exhaust from the burning of diesel fuel is a complex mixture of vapors, gases, and fine particles, including over 40 known pollutants like nitrogen oxide and known or suspected carcinogenic substances such as benzene, arsenic, and formaldehyde.
Exposure to diesel exhaust irritates the eyes, nose, throat and lungs, causing coughs, headaches, light-headedness and nausea, while causing people with allergies to be more susceptible allergy triggers like dust or pollen.
Many particles in disease fuel are so tiny they are able to penetrate deep into the lungs when inhaled.
Diesel fuel particles appear to have even greater immunologic effects in the presence of environmental allergens than they do alone.
Children living along major trucking thoroughfares are at increased risk for asthmatic and allergic symptoms and are more likely to have respiratory dysfunction.
The damaging effects of diesel fuel pollution go beyond a synergistic role in asthma development.
Exposure to a combination of microscopic diesel fuel particles among people with high blood cholesterol increases the risk for both heart attack and stroke above levels found among those exposed to only one of these health risks.
Adding diesel particles to cholesterol fats creates a dangerous synergy that wreaks cardiovascular havoc far beyond what’s caused by the diesel or cholesterol alone.
The two mechanisms work in tandem to stimulate genes that promote cell inflammation, a primary risk for hardening and blockage of blood vessels and, as narrowed arteries collect cholesterol deposits and trigger blood clots, for heart attacks and strokes as well.
There is a need to better understand processes of interaction between specific diseases with each other and with health-related factors like malnutrition, structural violence, discrimination, stigmatization, and toxic environmental exposure that reflect oppressive social relationships.